Reconsidering stepped wedge cluster randomized trial designs with implementation periods: Fewer sequences or the parallel-group design with baseline and implementation periods are potentially more efficient

BACKGROUND/AIMS

When designing a cluster randomized trial, advantages and disadvantages of tentative designs must be weighed. The stepped wedge design is popular for multiple reasons, including its potential to increase power via improved efficiency relative to a parallel-group design. In many realistic settings, it will take time for clusters to fully implement the intervention. When designing the HEALing (Helping to End Addiction Long-termSM) Communities Study, implementation time was a major consideration, and we examined the efficiency and practicality of three designs. Specifically, a three-sequence stepped wedge design with implementation periods, a corresponding two-sequence modified design that is created by removing the middle sequence, and a parallel-group design with baseline and implementation periods. In this article, we study the relative efficiencies of these specific designs. More generally, we study the relative efficiencies of modified designs when the stepped wedge design with implementation periods has three or more sequences. We also consider different correlation structures.

METHODS

We compare efficiencies of stepped wedge designs with implementation periods consisting of three to nine sequences with a variety of corresponding designs. The three-sequence design is compared to the two-sequence modified design and to the parallel-group design with baseline and implementation periods analysed via analysis of covariance. Stepped wedge designs with implementation periods consisting of four or more sequences are compared to modified designs that remove all or a subset of 'middle' sequences. Efficiencies are based on the use of linear mixed effects models.

RESULTS

In the studied settings, the modified design is more efficient than the three-sequence stepped wedge design with implementation periods. The parallel-group design with baseline and implementation periods with analysis of covariance-based analysis is often more efficient than the three-sequence design. With respect to stepped wedge designs with implementation periods that are comprised of more sequences, there are often corresponding modified designs that improve efficiency. However, use of only the first and last sequences has the potential to be either relatively efficient or inefficient. Relative efficiency is impacted by the strength of the statistical correlation among outcomes from the same cluster; for example, the relative efficiencies of modified designs tend to be greater for smaller cluster auto-correlation values.

CONCLUSION

If a three-sequence stepped wedge design with implementation periods is being considered for a future cluster randomized trial, then a corresponding modified design using only the first and last sequences should be considered if sole focus is on efficiency. However, a parallel-group design with baseline and implementation periods and analysis of covariance-based analysis can be a practical, efficient alternative. For stepped wedge designs with implementation periods and a larger number of sequences, modified versions that remove 'middle' sequences should be considered. Due to the potential sensitivity of design efficiencies, statistical correlation should be carefully considered.

Alternatives to dental opioid prescribing after tooth extraction (ADOPT): protocol for a stepped wedge cluster randomized trial

BACKGROUND

Dentists and oral surgeons are leading prescribers of opioids to adolescents and young adults (AYA), who are at high risk for developing problematic opioid use after an initial exposure. Most opioids are prescribed after tooth extraction, but non-opioid analgesics provide similar analgesia and are recommended by multiple professional organizations.

METHODS

This multi-site stepped wedge cluster-randomized trial will assess whether a multicomponent behavioral intervention can influence opioid prescribing behavior among dentists and oral surgeons compared to usual practice. Across up to 12 clinical practices (clusters), up to 33 dentists/oral surgeons (provider participants) who perform tooth extractions for individuals 12-25 years old will be enrolled. After enrollment, all provider participants will receive the intervention at a time based on the sequence to which their cluster is randomized. The intervention consists of prescriber education via academic detailing plus provision of standardized patient post-extraction instructions and blister packs of acetaminophen and ibuprofen. Provider participants will dispense the blister packs and distribute the patient instructions at their discretion to AYA undergoing tooth extraction, with or without additional analgesics. The primary outcome is a binary, patient-level indicator of electronic post-extraction opioid prescription. Data for the primary outcome will be collected from the provider participant's electronic health records quarterly throughout the study. Provider participants will complete a survey before and approximately 3 months after transitioning into the intervention condition to assess implementation outcomes. AYA patients undergoing tooth extraction will be offered a survey to assess pain control and satisfaction with pain management in the week after their extraction. Primary analyses will use generalized estimating equations to compare the binary patient-level indicator of being prescribed a post-extraction opioid in the intervention condition compared to usual practice. Secondary analyses will assess provider participants' perceptions of feasibility and appropriateness of the intervention, and patient-reported pain control and satisfaction with pain management. Analyses will adjust for patient-level factors (e.g., sex, number of teeth extracted, etc.).

DISCUSSION

This real-world study will address an important need, providing information on the effectiveness of a multicomponent intervention at modifying dental prescribing behavior and reducing opioid prescriptions to AYA.

CLINICALTRIALS

GOV: NCT06275191.

Effects of the Communities that Heal (CTH) intervention on perceived opioid-related community stigma in the HEALing Communities Study: results of a multi-site, community-level, cluster-randomized trial

Background

Community stigma against people with opioid use disorder (OUD) and intervention stigma (e.g., toward naloxone) exacerbate the opioid overdose crisis. We examined the effects of the Communities that HEAL (CTH) intervention on perceived opioid-related community stigma by stakeholders in the HEALing Communities Study (HCS).

Methods

We collected three surveys from community coalition members in 66 communities across four states participating in HCS. Communities were randomized into Intervention (Wave 1) or Wait-list Control (Wave 2) arms. We conducted multilevel linear mixed models to compare changes in primary outcomes of community stigma toward people treated for OUD, naloxone, and medication for opioid use disorder (MOUD) by arm from time 1 (before the start of the intervention) to time 3 (end of the intervention period in the Intervention arm).

Findings

Intervention stakeholders reported a larger decrease in perceived community stigma toward people treated for OUD (adjusted mean change (AMC) -3.20 [95% C.I. -4.43, -1.98]) and toward MOUD (AMC -0.33 [95% C.I. -0.56, -0.09]) than stakeholders in Wait-list Control communities (AMC -0.18 [95% C.I. -1.38, 1.02], p = 0.0007 and AMC 0.11 [95% C.I. -0.09, 0.31], p = 0.0066). The relationship between intervention status and change in stigma toward MOUD was moderated by rural-urban status (urban AMC -0.59 [95% CI, -0.87, -0.32], rural AMC not sig.) and state. The difference in stigma toward naloxone between Intervention and Wait-list Control stakeholders was not statistically significant (p = 0.18).

Interpretation

The CTH intervention decreased stakeholder perceptions of community stigma toward people treated for OUD and stigma toward MOUD. Implementing the CTH intervention in other communities could decrease OUD stigma across diverse settings nationally.

Funding

US National Institute on Drug Abuse.

Equity of overdose education and naloxone distribution provided in the Kentucky HEALing Communities Study

Background

Opioid overdoses differentially affect demographic groups. Strategies to reduce overdose deaths, specifically overdose education and naloxone distribution (OEND), are not consistently delivered equitably.

Methods

The HEALing Communities StudySM (HCS) is a cluster-randomized trial designed to implement evidence-based practices, including OEND, to reduce overdose deaths across communities. Individuals receiving OEND in eight Kentucky counties between January 2020 and June 2022 provided demographics and overdose history. Recipient characteristics were compared to opioid overdose decedent characteristics to evaluate whether OEND was equitably delivered to the target population. Recipient characteristics were also analyzed based on whether OEND was delivered in criminal justice, behavioral health, or health care facilities.

Results

A total of 26,273 demographic records were analyzed from 137 partner agencies. Most agencies were in behavioral health (85.6 %) or criminal justice sectors (10.4 %). About half of OEND recipients were male (50.6 %), which was significantly lower than the 70.3 % of overdose decedents who were male, (p<0.001). OEND recipients tended to be younger than overdose decedents, but there were not significant differences in race/ethnicity between OEND recipients and overdose decedents. Over 40 % of OEND recipients had overdosed, and 68.9 % had witnessed a prior overdose. There were notable differences across facility types, as males and Black individuals accounted for fewer OEND recipients in addiction treatment facilities compared to jails.

Conclusion

Although OEND recipients' demographics resembled those of decedents, specific attention should be paid to ensuring equitable OEND access. Variation in OEND uptake by facility type may reflect biases and barriers to care.

Neonatal Abstinence Signs during Treatment: Trajectory, Resurgence and Heterogeneity

Neonatal abstinence syndrome (NAS) presents with a varying severity of withdrawal signs and length of treatment (LOT). We examined the course and relevance of each of the NAS withdrawal signs during treatment in a sample of 182 infants with any prenatal opioid exposure, gestational age ≥ 35 weeks, without other medical conditions, and meeting the criteria for pharmacological treatment. Infants were monitored using the Finnegan Neonatal Abstinence Scoring Tool. Daily mean Finnegan scores were estimated using linear mixed models with random subject effects to account for repeated withdrawal scores from the same subject. Daily item prevalence was estimated using generalized estimating equations with a within-subject exchangeable correlation structure. The median LOT was 12.86 days. The prevalence of withdrawal signs decreased from day one to day three of treatment. However, certain central nervous system (CNS) and gastrointestinal (GI) signs showed sporadic increases in prevalence notable around two weeks of treatment, accounting for increases in Finnegan scores that guided pharmacotherapy. We question whether the resurgence of signs with a prolonged LOT is mainly a consequence of opioid tolerance or withdrawal. Monitoring CNS and GI signs throughout treatment is crucial. Future studies directed to better understand this clinical phenomenon may lead to the refining of NAS pharmacotherapy and perhaps the discovery of treatment alternatives.

Examination of naloxone dosing patterns for opioid overdose by emergency medical services in Kentucky during increased fentanyl use from 2018 to 2021

BACKGROUND

Fatal overdoses involving fentanyl/fentanyl analogs (F/FA) have increased in the US, raising questions about naloxone doses for F/FA overdose reversal. Emergency medical services (EMS) data provide an opportunity to examine naloxone administration changes as fentanyl increases in the illicit opioid supply.

METHODS

Administered naloxone intranasal-equivalent total dose (INTD) in milligrams (mg) was calculated for Kentucky EMS suspected opioid overdose (SOO) encounters (n=33,846), 2018-2021, and patterns of administration were examined. County-level F/FA availability was measured as 1) proportion of fatal drug overdoses involving F/FA, and 2) F/FA police seizures. Linear mixed models estimated changes in INTD in relation to local F/FA availability accounting for patient characteristics.

RESULTS

From 2018-2021, SOOs increased by 44% (6853 to 9888) with an average INTD increase from 4.5mg to 4.7mg, with more than 99% of encounters resulting in successful reversal each year. For SOO encounters examined by outcome at the scene (i.e., non-fatal fatal vs fatal), average INTD for non-fatal were 4.6mg compared to 5.9mg for fatal overdoses. Mixed modeling found no significant relationship between INTD and the two measures for local F/FA availability.

CONCLUSION

As F/FA-involved overdose risk increased, we observed a modest increase in INTD administered in SOO EMS encounters - just slightly higher than the 4mg standard dose. The lack of significant relationship between F/FA and naloxone dose suggests that naloxone utilization in SOO with EMS involvement remains effective for overdose reversal, and that EMS naloxone dosing patterns have not changed substantially.

Risk factors of carbapenemase-producing Enterobacterales acquisition among adult intensive care unit patients at a Kentucky Academic Medical Center

Background

Acquisition of carbapenemase-producing carbapenem-resistant Enterobacterales (CP-CRE) are associated with negative health outcomes. Our adult intensive care unit (ICU) population has experienced low levels of CP-CRE acquisition; however, specific risk factors for this population at our medical facility have not been studied.

Aims

To identify risk factors of CP-CRE acquisition and describe CP-CRE epidemiology among adult ICU patients at our medical facility.

Methods

A retrospective cohort study was performed at a Kentucky Academic Medical Center. Surveillance specimens were collected at admission and weekly thereafter to identify CP-CRE colonization. Clinical data were extracted from patient medical records. Cases were defined as those who tested positive for CP-CRE on ICU admission day 3 or greater. Risk of CP-CRE acquisition was calculated using Modified Poisson regression.

Findings

Independent risk factors of CP-CRE acquisition included administration of enteral tube feeds (risk ratio [RR], 4.46; 95% confidence interval [CI], 1.74-11.43); diagnosis of Clostridioides difficile enterocolitis (RR, 3.51; 95% CI, 1.27-9.68), pressure ulcer (RR, 3.48; 95% CI, 1.91-6.36), and morbid obesity (RR, 2.10; 95% CI, 1.12-3.95); having a drainage tube (RR, 2.63; 95% CI, 1.38-4.98); admission to a medical ICU (RR, 2.39; 95% CI, 1.32-4.35); 90-day use of a carbapenem (RR, 2.27; 95% CI, 1.21-4.26); and dialysis procedure (RR, 2.22; 95% CI, 1.15-4.27).

Conclusion

Most CP-CRE risk factors were associated with alteration of colon microbiota and/or invasive procedures/devices. These results will assist in creating a more targeted CP-CRE active surveillance system and highlight areas for infection prevention intervention.

Telemedicine Buprenorphine Initiation and Retention in Opioid Use Disorder Treatment for Medicaid Enrollees

Importance

Early COVID-19 mitigation strategies placed an additional burden on individuals seeking care for opioid use disorder (OUD). Telemedicine provided a way to initiate and maintain transmucosal buprenorphine treatment of OUD.

Objective

To examine associations between transmucosal buprenorphine OUD treatment modality (telemedicine vs traditional) during the COVID-19 public health emergency and the health outcomes of treatment retention and opioid-related nonfatal overdose.

Design, Setting, and Participants

This retrospective cohort study was conducted using Medicaid claims and enrollment data from November 1, 2019, to December 31, 2020, for individuals aged 18 to 64 years from Kentucky and Ohio. Data were collected and analyzed in June 2022, with data updated during revision in August 2023.

Exposures

The primary exposure of interest was the modality of the transmucosal buprenorphine OUD treatment initiation. Relevant patient demographic and comorbidity characteristics were included in regression models.

Main Outcomes and Measures

There were 2 main outcomes of interest: retention in treatment after initiation and opioid-related nonfatal overdose after initiation. For outcomes measured after initiation, a 90-day follow-up period was used. The main analysis used a new-user study design; transmucosal buprenorphine OUD treatment initiation was defined as initiation after more than a 60-day gap in buprenorphine treatment. In addition, uptake of telemedicine for buprenorphine was examined, overall and within patients initiating treatment, across quarters in 2020.

Results

This study included 41 266 individuals in Kentucky (21 269 women [51.5%]; mean [SD] age, 37.9 [9.0] years) and 50 648 individuals in Ohio (26 425 women [52.2%]; mean [SD] age, 37.1 [9.3] years) who received buprenorphine in 2020, with 18 250 and 24 741 people initiating buprenorphine in Kentucky and Ohio, respectively. Telemedicine buprenorphine initiations increased sharply at the beginning of 2020. Compared with nontelemedicine initiation, telemedicine initiation was associated with better odds of 90-day retention with buprenorphine in both states (Kentucky: adjusted odds ratio, 1.13 [95% CI, 1.01-1.27]; Ohio: adjusted odds ratio, 1.19 [95% CI, 1.06-1.32]) in a regression analysis adjusting for patient demographic and comorbidity characteristics. Telemedicine initiation was not associated with opioid-related nonfatal overdose (Kentucky: adjusted odds ratio, 0.89 [95% CI, 0.56-1.40]; Ohio: adjusted odds ratio, 1.08 [95% CI, 0.83-1.41]).

Conclusions and Relevance

In this cohort study of Medicaid enrollees receiving buprenorphine for OUD, telemedicine buprenorphine initiation was associated with retention in treatment early during the COVID-19 pandemic. These findings add to the literature demonstrating positive outcomes associated with the use of telemedicine for treatment of OUD.

A Field-expedient Arm Care Screening Tool Can Identify Musculoskeletal Risk Factors in Baseball Players

BACKGROUND

Preseason movement screening can identify modifiable risk factors, deterioration of function, and potential for injury in baseball players. Limited resources and time prevent high school baseball coaches from performing movement screens on their players.

HYPOTHESIS

The arm care screen (ACS) will be highly sensitive to detecting musculoskeletal risk factors.

STUDY DESIGN

Cross-sectional.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 150 baseball players were independently scored on the ACS electronically by reviewing a video recording of each player's screening performance. Discriminability of the ACS was determined with a 2 × 2 contingency table dichotomizing musculoskeletal risk factors as present or absent based on a predetermined cutoff value and those who passed or failed the corresponding ACS subtest.

RESULTS

High sensitivity was observed on the reciprocal shoulder mobility (0.89; 95% CI 0.81-0.94), 90/90 total body rotation (0.86; 95% CI 0.79-0.92), and lower body diagonal reach (0.85; 95% CI 0.78-0.91) tests of the ACS suggesting sufficient ability to identify musculoskeletal impairments and risk factors.

CONCLUSION

The ACS is a simplistic screening tool that the coach can administer to discriminate between youth, high school, and college-level baseball players who possess musculoskeletal risk factors. The ACS subtests demonstrated high sensitivity for correctly identifying musculoskeletal risk factors common in baseball players and can be useful as a screening tool for baseball coaches developing arm care exercise programs.

CLINICAL RELEVANCE

A field-expedient screen could provide coaches the ability to identify musculoskeletal risk factors that need to be addressed to minimize injury risk factors in a time-efficient manner.

Effects of dynamic body weight support on functional independence measures in acute ischemic stroke: a retrospective cohort study

BACKGROUND

Stroke remains a major public health concern in the United States and a leading cause of long-term disability in adults. Dynamic body weight support (DBWS) systems are popular technology available for use in clinical settings such inpatient rehabilitation. However, there remains limited studies in such inpatient settings that compare DBWS to standard of care (SOC) using real world outcome measures. For survivors of acute ischemic stroke, we determine if incorporating a dynamic body weight support (DBWS) system into inpatient therapy offers greater improvement than standard of care (SOC).

METHODS

A retrospective chart review included 52 individuals with an acute ischemic stroke admitted to an inpatient rehabilitation facility. Functional Independence Measure (FIM) data, specifically changes in FIM at discharge, served as the primary outcome measure. Patient cohorts received either therapies per SOC or therapies incorporating DBWS. Regardless of cohort group, all patients underwent therapies for 3 h per day for 5 days a week.

RESULTS

For both groups, a statistically and clinically significant increase in total FIM (P < 0.0001) was observed at discharge compared to at admission. Improvements for the DBWS group were significantly greater than the SOC group as evidenced by higher gains in total FIM (p = 0.04) and this corresponded to a medium effect size (Cohen's d = 0.58). Among FIM subscores, the DBWS group achieved a significant increase in sphincter control while all other subscore changes remained non-significant.

CONCLUSIONS

This preliminary evidence supports the benefit of using DBWS during inpatient rehabilitation in individuals who have experienced an acute ischemic stroke. This may be due to the greater intensity and repetitions of tasks allowed by DBWS. These preliminary findings warrant further investigations on the use of DBWS in inpatient settings.

A New Look at Barriers to Clinical Care Among Appalachian Residents Living With Diabetes

In the United States, diabetes is the seventh leading cause of death and continues to rise in prevalence, with type 2 diabetes accounting for 90-95% of all cases. Rates of diabetes in Kentucky, and, in particular, the Appalachian region, are among the highest in the nation and are increasing faster than the national average. Despite this disproportionate burden, barriers to clinical appointment attendance have not been fully explored in this population. This article examines the association among perceived barriers to clinical attendance, glycemic control, and diabetes self-care as part of an ongoing study. We used a 25-item checklist developed using the Chronic Care Model to assess participants' barriers to clinic attendance. Glycemic control was assessed via A1C measurement. Diabetes self-care was assessed using the Summary of Diabetes Self-Care Activities measure. At the time of analysis, 123 of the 356 participants (34.6%) did not report any barriers to clinic attendance. For the remainder, the major reported barriers included forgetting appointments, inability to afford medicines or other treatment, and placing faith above medical care. The average A1C was 7.7%, and the average diabetes self-care summary score was 17.1 out of 35 points (with higher values indicating better self-care). Missing clinic appointments is associated with lower health outcomes, especially in vulnerable populations. This study can help educate clinic staff on perceived barriers to type 2 diabetes management among people with diabetes in Appalachia.

The relationship between psychosocial factors, self-care, and blood sugar in an Appalachian population

Introduction

Appalachian residents are more likely than other populations to have Type 2 Diabetes Mellitus (T2DM) and to experience more severe complications from the disease, including excess and premature mortality.

Methods

This study examines health alongside sociodemographic factors, psychosocial factors (including knowledge, empowerment, social support/function, religiosity, distress), and perceived problems in diabetes management that may influence self-care and HbA1c among vulnerable rural residents. A survey of a community-based sample of 356 adults with diagnosed diabetes or HbA1c > 6.5 was conducted in six counties in Appalachian Kentucky.

Results

Findings suggest that neither religiosity nor social support/function mediate/moderate the relationship between psychosocial factors and dependent variables (problem areas in diabetes, T2DM self-care or HbA1c). Results also suggest that distress is a predictor of problem areas in diabetes, and both distress and empowerment are predictors of T2DM self-care.

Implications

This study addresses the gap in the literature concerning the influence of psychosocial factors on problem areas in diabetes, T2DM self-care and HbA1c among vulnerable rural residents, as well as the potential mediating/modifying effects of religiosity and social function/support. Future research is needed to inform strategies for identifying and addressing distress among vulnerable populations burdened by T2DM, including Appalachian adults.

Behavioral Parent Training for Families With Young Deaf or Hard of Hearing Children Followed in Hearing Health Care

PURPOSE

It is well established that individuals with a communication disability, including being deaf or hard of hearing (DHH), experience inequities in health services and outcomes. These inequities extend to DHH children's access to psychosocial evidence-based interventions (EBIs). Behavioral parent training is an EBI that can be used to improve caregiver and child outcomes. Despite being supported by decades of effectiveness research, this EBI is rarely accessed by, or studied with, caregivers of DHH children. The purpose of this article is to describe a program of stakeholder-engaged research adapting and assessing behavioral parent training with caregivers of young DHH children followed in hearing health care, aimed at reducing inequities in access to this EBI.

METHOD

The first section briefly summarizes the literature on disruptive behavior problems in young children, with a focus on preschool-age DHH children. The evidence base for behavioral parent training is described. Next, the gaps in knowledge and practice regarding disruptive behaviors among DHH children are highlighted, and the potential integration of behavioral parent training into the standard of care for this population is proposed.

CONCLUSIONS

Young DHH children who use hearing aids and/or cochlear implants experience disruptive behavior problems at rates at least as high as typically hearing children, but their access to EBIs is limited, and behavioral parent training programs tailored to this population have not been rigorously tested. Caregivers and hearing health care service providers affirm the potential benefits of behavioral parent training and were partners in adapting this EBI. This research highlights several principles and approaches essential for reducing inequities and improving the quality of life not only for DHH children and their families but also for individuals with communication disabilities more broadly: engagement of key stakeholders in research, collaboration across disciplines, and using implementation science methods and models to design for implementation, dissemination, and sustainment. Presentation Video: https://doi.org/10.23641/asha.21215900.

Influence of pregabalin maintenance on cannabis effects and related behaviors in daily cannabis users

No medications are approved for cannabis use disorder (CUD), though a small clinical trial demonstrated that the voltage-dependent calcium channel (VDCC) ligand gabapentin reduced cannabis use in treatment seekers. VDCCs are modulated by cannabinoid (CB) ligands, and there are shared effects between CB agonists and VDCC ligands. This overlapping neuropharmacology and the initial clinical results supported the evaluation of pregabalin, a "next-generation" VDCC ligand, as a CUD medication. Two separate placebo-controlled, double-blind, counterbalanced, within-subjects human laboratory studies tested placebo and 300 (N = 2 females, 11 males; Experiment [EXP] 1) or 450 (N = 3 females, 11 males; EXP 2) mg/day pregabalin in cannabis users who were not seeking treatment or trying to reduce/quit their cannabis use. The protocol consisted of two outpatient maintenance phases (11 days in EXP 1 and 15 days in EXP 2) that concluded with four experimental sessions within each phase. During experimental sessions, maintenance continued, and participants completed two 2-day blocks of sampling and self-administration sessions to determine the reinforcing effects of smoked cannabis (0% and 5.9% delta⁹-tetrahydrocannabinol [THC]), as well as subjective, attentional bias, performance, and physiological responses. In addition, naturalistic cannabis use, side effects, sleep quality, craving, and other self-reported substance use were measured during pregabalin maintenance. Cannabis was self-administered and produced prototypical effects, but pregabalin generally did not impact the effects of cannabis or alter naturalistic use. These human laboratory results in cannabis users not trying to reduce/quit their use do not support the efficacy of pregabalin as a stand-alone pharmacotherapy for CUD. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Performance of model-based vs. permutation tests in the HEALing (Helping to End Addiction Long-termSM) Communities Study, a covariate-constrained cluster randomized trial

BACKGROUND

The HEALing (Helping to End Addiction Long-term^SM) Communities Study (HCS) is a multi-site parallel group cluster randomized wait-list comparison trial designed to evaluate the effect of the Communities That Heal (CTH) intervention compared to usual care on opioid overdose deaths. Covariate-constrained randomization (CCR) was applied to balance the community-level baseline covariates in the HCS. The purpose of this paper is to evaluate the performance of model-based tests and permutation tests in the HCS setting. We conducted a simulation study to evaluate type I error rates and power for model-based and permutation tests for the multi-site HCS as well as for a subgroup analysis of a single state (Massachusetts). We also investigated whether the maximum degree of imbalance in the CCR design has an impact on the performance of the tests.

METHODS

The primary outcome, the number of opioid overdose deaths, is count data assessed at the community level that will be analyzed using a negative binomial regression model. We conducted a simulation study to evaluate the type I error rates and power for 3 tests: (1) Wald-type t-test with small-sample corrected empirical standard error estimates, (2) Wald-type z-test with model-based standard error estimates, and (3) permutation test with test statistics calculated by the difference in average residuals for the two groups.

RESULTS

Our simulation results demonstrated that Wald-type t-tests with small-sample corrected empirical standard error estimates from the negative binomial regression model maintained proper type I error. Wald-type z-tests with model-based standard error estimates were anti-conservative. Permutation tests preserved type I error rates if the constrained space was not too small. For all tests, the power was high to detect the hypothesized 40% reduction in opioid overdose deaths for the intervention vs. comparison group both for the overall HCS and the subgroup analysis of Massachusetts (MA).

CONCLUSIONS

Based on the results of our simulation study, the Wald-type t-test with small-sample corrected empirical standard error estimates from a negative binomial regression model is a valid and appropriate approach for analyzing cluster-level count data from the HEALing Communities Study.

TRIAL REGISTRATION

ClinicalTrials.gov http://www.

CLINICALTRIALS

gov ; Identifier: NCT04111939.

Broadband internet subscription rates and opioid prescribing via telemedicine during the COVID-19 pandemic

PURPOSE

In response to the COVID-19 pandemic, the US DEA allowed controlled substance prescriptions to be issued following a telemedicine encounter. This study evaluated changes in opioid prescribing in Kentucky counties with low and high rates of broadband subscription before, during, and after a series of statewide emergency declarations that may have affected health care access.

METHODS

The study used the prescription drug monitoring program to analyze records of opioid analgesic prescriptions dispensed to opioid-naïve individuals in high (N = 26) and low (N = 94) broadband access counties during 3 periods: before a state of emergency (SOE) and executive order (EO) limiting nonemergent health care services (January 2019-February 2020), while the EO was active (March-April 2020), and after health care services began reopening (May-December 2020). Marginal generalized estimating equations-type negative binomial models were fit to compare prescription counts by broadband access over the 3 periods.

FINDINGS

Rates of opioid dispensing to opioid-naïve individuals decreased significantly during the EO, but increased nearly to pre-SOE levels after health care services began reopening. Dispensing rates in low broadband counties were higher than those in high broadband counties during all time periods, although these differences were negligible after adjusting for potential confounders. During the EO, prescriptions were written for longer days' supply in both county types.

CONCLUSIONS

The overall dramatic reduction in opioid prescribing rates should be considered when evaluating annual opioid prescribing trends. However, broadband subscription rate did not appear to influence opioid prescriptions dispensed in Kentucky during the EO.

Study Protocol: Type 1 Hybrid Effectiveness-Implementation Trial of a Behavioral Parent Training Intervention for Parents of Young Children Who Are Deaf or Hard of Hearing

PURPOSE

Children who are deaf or hard of hearing (DHH) and who use hearing aids or cochlear implants are more likely than their peers with typical hearing to exhibit behavior problems. Although multiple evidence-based interventions for child behavior problems exist, they are rarely delivered to children who are DHH, and no rigorous randomized controlled trials have been conducted to determine their effects with this population. This protocol describes a study aiming to test the effectiveness of an evidence-based behavioral parent training intervention adapted for parents of young children who are DHH and simultaneously to assess key implementation outcomes and multilevel contextual factors influencing implementation.

METHOD

The protocol for a Type 1 hybrid effectiveness-implementation trial of a behavioral parent training intervention for parents of young children who are DHH is presented, including details of the study design, participants, assessments, and analyses. Using a stakeholder-engaged, mixed-methods approach, we will test the effects of the intervention versus treatment as usual on parenting behaviors, child behaviors, and a range of secondary effectiveness outcomes, including adherence to using hearing aids and cochlear implants as well as measures of child speech and language. We will assess the acceptability, feasibility, fidelity, and costs of the intervention from the perspectives of peer coaches who deliver the intervention, hearing health care clinicians (including audiologists and speech-language pathologists), and administrators of programs serving young children who are DHH.

CONCLUSIONS

Results of this trial will inform future efforts to close the gap between prevalence of behavioral problems in young children who are DHH and access to and use of evidence-based interventions to prevent and treat them. If effective, this intervention could be widely implemented using strategies informed by the findings of this study to benefit young children who are DHH and followed in hearing health care and their families.

Marginal modeling in community randomized trials with rare events: Utilization of the negative binomial regression model

BACKGROUND/AIMS

This work is motivated by the HEALing Communities Study, which is a post-test only cluster randomized trial in which communities are randomized to two different trial arms. The primary interest is in reducing opioid overdose fatalities, which will be collected as a count outcome at the community level. Communities range in size from thousands to over one million residents, and fatalities are expected to be rare. Traditional marginal modeling approaches in the cluster randomized trial literature include the use of generalized estimating equations with an exchangeable correlation structure when utilizing subject-level data, or analogously quasi-likelihood based on an over-dispersed binomial variance when utilizing community-level data. These approaches account for and estimate the intra-cluster correlation coefficient, which should be provided in the results from a cluster randomized trial. Alternatively, the coefficient of variation or R coefficient could be reported. In this article, we show that negative binomial regression can also be utilized when communities are large and events are rare. The objectives of this article are (1) to show that the negative binomial regression approach targets the same marginal regression parameter(s) as an over-dispersed binomial model and to explain why the estimates may differ; (2) to derive formulas relating the negative binomial overdispersion parameter k with the intra-cluster correlation coefficient, coefficient of variation, and R coefficient; and (3) analyze pre-intervention data from the HEALing Communities Study to demonstrate and contrast models and to show how to report the intra-cluster correlation coefficient, coefficient of variation, and R coefficient when utilizing negative binomial regression.

METHODS

Negative binomial and over-dispersed binomial regression modeling are contrasted in terms of model setup, regression parameter estimation, and formulation of the overdispersion parameter. Three specific models are used to illustrate concepts and address the third objective.

RESULTS

The negative binomial regression approach targets the same marginal regression parameter(s) as an over-dispersed binomial model, although estimates may differ. Practical differences arise in regard to how overdispersion, and hence the intra-cluster correlation coefficient is modeled. The negative binomial overdispersion parameter is approximately equal to the ratio of the intra-cluster correlation coefficient and marginal probability, the square of the coefficient of variation, and the R coefficient minus 1. As a result, estimates corresponding to all four of these different types of overdispersion parameterizations can be reported when utilizing negative binomial regression.

CONCLUSION

Negative binomial regression provides a valid, practical, alternative approach to the analysis of count data, and corresponding reporting of overdispersion parameters, from community randomized trials in which communities are large and events are rare.

Magnetic twitch assessment of diaphragm and quadriceps weakness in critically ill mechanically ventilated patients

Critically ill mechanically ventilated (MV) patients develop significant muscle weakness, which has major clinical consequences. There remains uncertainty, however, regarding the severity of leg weakness, the precise relationship between muscle strength and thickness, and the risk factors for weakness in MV patients. We therefore measured both diaphragm (PdiTw) and quadriceps (QuadTw) strength in MV patients using magnetic stimulation and compared strength to muscle thickness. Both PdiTw and QuadTw were profoundly reduced for MV patients, with PdiTw 19 % of normal and QuadTw 6% of normal values. There was a poor correlation between strength and thickness for both muscles, with thickness often remaining in the normal range when strength was severely reduced. Regression analysis revealed reductions in PdiTw correlated with presence of infection (p = 0.006) and age (p = 0.007). QuadTw best correlated with duration of MV (p = 0.036). Limb muscles are profoundly weak in critically ill patients, with a severity that mirrors the level of weakness observed in the diaphragm.

Understanding the effects of opioids vs non-opioids in the treatment of neonatal abstinence syndrome, an in vitro model

Neonatal abstinence syndrome (NAS) refers to cadre of withdrawal manifestations in infants born to mothers who used illicit and licit substances during pregnancy. The increasing prevalence of NAS has been largely due to the maternal use of opioids during pregnancy. NAS contributes to increased morbidity and long-term disability in surviving infants. Clinically, oral opioid therapies for opioid exposure have been a standard treatment with morphine (MO) being the most commonly used medication. Recently, a non-opioid agent, clonidine (CD) has also been used with potentially favorable short- and long-term outcomes in infants. However, data regarding the cellular and molecular effects of these treatments on the developing brain is still lacking due to a lack of a reliable animal model that targets the neonatal brain. To address this gap in knowledge we determined the effects of MO or CD on the cell death of neonatal cortical explant cultures that were exposed to oxycodone (OXY) in utero. Sprague Dawley rats were randomized and implanted with programmable infusion pumps before mating to receive either the OXY (dose increasing from 1.21-1.90 mg/kg/day to a maximum dose of 2.86-3.49 mg/kg/day) or normal saline (NS) throughout pregnancy and until one week after delivery. Male and female rat pups were sacrificed on postnatal day 4, and the prefrontal cortex (PFC) and hippocampus (HC) were dissected and treated with MO (0.10-1.00 µM) or CD (1.20-120.00 µM) in culture media. After 5 days of treatment the explants were labeled with propidium iodide to detect cell death. Dead cells were analyzed and counted under fluorescence microscopy. In explants from the PFC, cell death was greater in those prenatally exposed to OXY and postnatally treated with MO (OXY/MO) (736.8 ± 76.5) compared to OXY/CD (620.9 ± 75.0; p = 0.005). In the HC explants, mean cell death counts were not significantly different between groups regardless of prenatal exposure or postnatal treatment (p = 0.19). The PFC is vital in controlling higher-order executive functions such as behavioral flexibility, learning and working memory. Therefore, our finding is consistent with executive function problems in children with prenatal opioid exposure.

Macrophages expressing uncoupling protein 1 increase in adipose tissue in response to cold in humans

Acute cold induces beige adipocyte protein marker expression in human subcutaneous white adipose tissue (SC WAT) from both the cold treated and contralateral leg, and the immune system regulates SC WAT beiging in mice. Cold treatment significantly increased the gene expression of the macrophage markers CD68 and 86 in SC WAT. Therefore, we comprehensively investigated the involvement of macrophages in SC WAT beiging in lean and obese humans by immunohistochemistry. Cold treatment significantly increased CD163/CD68 macrophages in SC WAT from the cold treated and contralateral legs of lean and obese subjects, and had similar effects on CD206/CD68 macrophages, whereas the effects on CD86/CD68 macrophages were inconsistent between lean and obese. However, linear regression analysis did not find significant relationships between the change in macrophage numbers and the change in UCP1 protein abundance. A high percentage of CD163 macrophages in SC WAT expressed UCP1, and these UCP1 expressing CD163 macrophages were significantly increased by cold treatment in SC WAT of lean subjects. In conclusion, our results suggest that CD163 macrophages are involved in some aspect of the tissue remodeling that occurs during SC WAT beiging in humans after cold treatment, but they are likely not direct mediators of the beiging process.

The Intra- and Inter-rater Reliability of an Arm Care Screening Tool in High School Baseball Coaches

BACKGROUND

Preseason movement screening can identify modifiable risk factors, deterioration of function, and potential for injury in baseball players. Limited resources and time intensive testing procedures prevent high school coaches from accurately performing frequent movement screens on their players.

PURPOSE

To establish the intra-rater and inter-rater reliability of a novel arm care screening tool based on the concepts of the Functional Movement Screen (FMS™) and Selective Functional Movement Assessment (SFMA™) in high school coaches.

STUDY DESIGN

Methodological intra- and inter-rater reliability study.

METHODS

Thirty-one male high school baseball players (15.9 years ± 1.06) were independently scored on the Arm Care Screen (ACS) by three examiners (two coaches, one physical therapist) in real-time and again seven days later by reviewing video recordings of each players' initial screening performance. Results from each examiner were compared within and between raters using Cohen's kappa and percent absolute agreement.

RESULTS

Substantial to excellent intra-rater and inter-rater reliability were established among all raters for each component of the ACS. The mean Cohen's kappa coefficient for intra-rater reliability was 0.76 (95% confidence interval, 0.54-0.95) and percent absolute agreement ranged from 0.82-0.94 among all raters. Inter-rater reliability demonstrated a mean Cohen's kappa value of 0.89 (95% confidence interval, 0.77-0.99) while percent absolute agreement between raters ranged from 0.81-1.00. Intra- and inter-rater reliability did not differ between raters with various movement screening experience (p>0.05).

CONCLUSIONS

High school baseball coaches with limited experience screening movement can reliably score all three components of the ACS in less than three minutes with minimal training.

LEVEL OF EVIDENCE

Level 3, Reliability study.

The mediating/moderating role of cultural context factors on self-care practices among those living with diabetes in rural Appalachia

Background

The aim of this study was to examine whether cultural factors, such as religiosity and social support, mediate/moderate the relationship between personal/psychosocial factors and T2DM self-care in a rural Appalachian community.

Methods

Regression models were utilized to assess for mediation and moderation. Multilevel linear mixed effects models and GEE-type logistic regression models were fit for continuous (social support, self-care) and binary (religiosity) outcomes, respectively.

Results

The results indicated that cultural context factors (religiosity and social support) can mediate/moderate the relationship between psychosocial factors and T2DM self-care. Specifically, after adjusting for demographic variables, the findings suggested that social support may moderate the effect of depressive symptoms and stress on self-care. Religiosity may moderate the effect of distress on self-care, and empowerment was a predictor of self-care but was not mediated/moderated by the assessed cultural context factors. When considering health status, religiosity was a moderately significant predictor of self-care and may mediate the relationship between perceived health status and T2DM self-care.

Conclusions

This study represents the first known research to examine cultural assets and diabetes self-care practices among a community-based sample of Appalachian adults. We echo calls to increase the evidence on social support and religiosity and other contextual factors among this highly affected population.

Trial registration

US National Library of Science identifier NCT03474731. Registered March 23, 2018, www.clinicaltrials.gov.

Intermittent Hypoxemia in Preterm Infants: A Potential Proinflammatory Process

OBJECTIVE

A major consequence of prematurity is intermittent hypoxemia (IH). Data from both adult studies and neonatal animal models suggest that IH is proinflammatory; however, there is limited data in preterm infants. Here, we assess the relationship between IH and systemic inflammation, namely, serum C-reactive protein (CRP) in preterm infants.

STUDY DESIGN

Serum CRP was measured at 30 days of life, at the time of peak IH frequency. IH measures (e.g., per cent time in hypoxemia, frequency, duration) were calculated the week prior to CRP collection. Statistical analyses were based on Spearman's correlation.

RESULTS

A total of 26 infants were included. Median gestational age and birth weight were 27^4/7 weeks and 980 g, respectively. There were positive correlations between primary IH measures and CRP levels, especially for events longer than 1-minute duration (r range: 0.56-0.74, all p < 0.01).

CONCLUSION

We demonstrate that IH is associated with increased CRP for the first time in preterm infants. Our findings are consistent with studies from adults and neonatal animal models suggesting that IH is a proinflammatory process.

KEY POINTS

· IH events are common.. · IH is associated with elevated C-reactive protein.. · Longer IH events (>1 min) are of most significance..

Which Risk Factors Are Associated with Pain and Patient-reported Function in Patients with a Rotator Cuff Tear?

BACKGROUND

Patient-reported measures guide physicians in clinical decision making and therefore it is critical to determine what clinical factors are associated with these scores. Psychological and physical factors are commonly studied separately in patients with rotator cuff tears to determine their influence on outcomes. It is well established that psychological distress and scapular motion change in the presence of a symptomatic rotator cuff tear. However, these factors have not been studied simultaneously in a clinical setting to determine their association with shoulder outcome scores.

QUESTION/PURPOSE

After controlling for relevant confounding variables, what physical and psychological factors are associated with better (1) American Shoulder and Elbow Surgeons (ASES) scores for function, (2) ASES pain scores, and (3) total ASES scores?

METHODS

Fifty-nine patients with a potential symptomatic rotator cuff tear were recruited and agreed to participate in this cross-sectional study. Of those, 85% (50 of 59) met eligibility criteria for a primary diagnosis of an MRI-confirmed symptomatic partial-thickness or full-thickness rotator cuff tear without a history of shoulder surgery. Demographics, rotator cuff tear size, arm flexion, and clinical scapular motion during active arm flexion were evaluated by experienced examiners using standardized procedures. Patients completed the ASES questionnaire and the Optimal Screening for Prediction of Referral and Outcomes-Yellow Flag assessment form, which measures 11 different pain-related psychological distress symptoms. Three separate stepwise multiple linear regression analyses were performed for ASES pain, function, and total scores, with significance set at p < 0.05.

RESULTS

This model found that ASES function scores were associated with four factors: older age, increased arm flexion, increased percentage of scapular external rotation during arm flexion, and increased scores for acceptance of chronic pain (adjusted r2 = 0.67; p = 0.01). Those four factors appear to explain 67% of the observed variance in ASES function scores in patients with rotator cuff tears. Furthermore, increased percentage of scapular external rotation during arm flexion and decreased fear-avoidance beliefs related to physical activity scores (adjusted r2 = 0.36; p < 0.01) were associated with better ASES pain scores. And finally, better ASES total scores were associated with four factors: increased arm flexion, increased percentage of scapular upward rotation, increased scapular external rotation during arm flexion, and decreased fear-avoidance beliefs related to physical activity scores (adjusted r2 = 0.65; p < 0.001).

CONCLUSION

Our results favor adopting a comprehensive biopsychological clinical assessment for patients with rotator cuff tears that specifically includes humeral and scapular motion, fear-avoidance behaviors, and pain coping behaviors along with demographics. These particular physical and psychological variables were found to be associated with the ASES and, therefore, should be clinically examined simultaneously and targeted as part of a tailored treatment plan.

LEVEL OF EVIDENCE

Level II, prognostic study.

Effect sizes and intra-cluster correlation coefficients measured from the Green Dot High School study for guiding sample size calculations when designing future violence prevention cluster randomized trials in school settings

Purpose

Cluster randomized controlled trials (cRCTs) are popular in school-based research designs where schools are randomized to different trial arms. To help guide future study planning, we provide information on anticipated effect sizes and intra-cluster correlation coefficients (ICCs), as well as school sizes, for dating violence (DV) and interpersonal violence outcomes based on data from a cRCT which evaluated the bystander-based violence intervention ‘Green Dot’.

Methods

We utilized data from 25 schools from the Green Dot High School study. Effect size and ICC values corresponding to dating and interpersonal violence outcomes are obtained from linear mixed effect models. We also calculated the required number of schools needed for future studies utilizing available methods that do and do not consider variation in school size.

Results

Observed effect sizes for DV outcomes range from 0.06 to 0.11. Observed ICC values for DV outcomes range from 0.0006 to 0.0032. The upper limit of 95% CIs for the true ICCs range from 0.0023 to 0.0070.

Conclusion

School-based evaluations with violence outcomes are expected to have small effect sizes. Observed ICCs are less than 0.005 and upper limit of of 95% CIs for the true ICCs are less than 0.01. Designing school-based cRCTs should account for the ICC, even if its value is assumed to be negligible. Furthermore, variation in school sizes should also be accounted for to avoid having too few schools to achieve the desired power.

A randomized controlled trial to determine whether beta-hydroxy-beta-methylbutyrate and/or eicosapentaenoic acid improves diaphragm and quadriceps strength in critically Ill mechanically ventilated patients

Background

Intensive care unit acquired weakness is a serious problem, contributing to respiratory failure and reductions in ambulation. Currently, there is no pharmacological therapy for this condition. Studies indicate, however, that both beta-hydroxy-beta-methylbutyrate (HMB) and eicosapentaenoic acid (EPA) increase muscle function in patients with cancer and in older adults. The purpose of this study was to determine whether HMB and/or EPA administration would increase diaphragm and quadriceps strength in mechanically ventilated patients.

Methods

Studies were performed on 83 mechanically ventilated patients who were recruited from the Medical Intensive Care Units at the University of Kentucky. Diaphragm strength was assessed as the trans-diaphragmatic pressure generated by supramaximal magnetic phrenic nerve stimulation (PdiTw). Quadriceps strength was assessed as leg force generated by supramaximal magnetic femoral nerve stimulation (QuadTw). Diaphragm and quadriceps thickness were assessed by ultrasound. Baseline measurements of muscle strength and size were performed, and patients were then randomized to one of four treatment groups (placebo, HMB 3 gm/day, EPA 2 gm/day and HMB plus EPA). Strength and size measurements were repeated 11 days after study entry. ANCOVA statistical testing was used to compare variables across the four experimental groups.

Results

Treatments failed to increase the strength and thickness of either the diaphragm or quadriceps when compared to placebo. In addition, treatments also failed to decrease the duration of mechanical ventilation after study entry.

Conclusions

These results indicate that a 10-day course of HMB and/or EPA does not improve skeletal muscle strength in critically ill mechanically ventilated patients. These findings also confirm previous reports that diaphragm and leg strength in these patients are profoundly low. Additional studies will be needed to examine the effects of other anabolic agents and innovative forms of physical therapy.

Trial registration: ClinicalTrials.gov, NCT01270516. Registered 5 January 2011, https://clinicaltrials.gov/ct2/show/NCT01270516?term=Supinski&draw=2&rank=4.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03737-9.

Clinical Outcomes of Molecular Tumor Boards: A Systematic Review

We conducted this systematic review to evaluate the clinical outcomes associated with molecular tumor board (MTB) review in patients with cancer.

METHODS

A systematic search of PubMed was performed to identify studies reporting clinical outcomes in patients with cancer who were reviewed by an MTB. To be included, studies had to report clinical outcomes, including clinical benefit, response, progression-free survival, or overall survival. Two reviewers independently selected studies and assessed quality with the Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group or the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies depending on the type of study being reviewed.

RESULTS

Fourteen studies were included with a total of 3,328 patients with cancer. All studies included patients without standard-of-care treatment options and usually with multiple prior lines of therapy. In studies reporting response rates, patients receiving MTB-recommended therapy had overall response rates ranging from 0% to 67%. In the only trial powered on clinical outcome and including a control group, the group receiving MTB-recommended therapy had significantly improved rate of progression-free survival compared with those receiving conventional therapy.

CONCLUSION

Although data quality is limited by a lack of prospective randomized controlled trials, MTBs appear to improve clinical outcomes for patients with cancer. Future research should concentrate on prospective trials and standardization of approach and outcomes.

A Nation-Wide Survey of High School Baseball Coaches' Perceptions Indicates their Arm Care Programs Play a Role in Injury Prevention

BACKGROUND

Arm care programs consisting of upper extremity strengthening and stretching have been recommended for injury prevention for pitchers of all ages. There has been no investigation into high school baseball coaches' usage and perceptions of arm care programs to mitigate physical impairments associated with injuries in baseball players.

HYPOTHESIS/PURPOSE

The purpose of this study was to investigate the current usage of arm care programs by high school baseball coaches. The primary objective was to determine if coaches use group-based or individualized arm care programs. The secondary objective sought to determine if the use of arm care programs is influenced by coaches' age, education, and experience level. Finally, this study explored the potential barriers to arm care implementation and high school baseball coaches' current awareness and beliefs of injury prevention.

STUDY DESIGN

Descriptive cross-sectional survey.

METHODS

A 29-item online survey was emailed to 18,500 high school baseball coaches throughout the United States. Data were collected for three months, and the response rate was 3.7%.

RESULTS

A total of 87.3% (n=571/654) of responding coaches use arm care programs with their players. Of coaches performing arm care, only 18.5% of 571 individualize their arm care exercises based on specific player needs. However, older and more experienced coaches are more likely to individualize their programs. Among the 12.7% (n=83/654) of coaches who do not use arm care programs, the two most commonly cited reasons for not implementing arm care were lack of observed benefit (41%) and insufficient staff (31%). Although 42% of 654 coaches recognized reduced shoulder mobility as a major contributor to injury, risk factors such as throwing with a fatigued arm, previous injury history, and throwing > 8 months per year were not consistently identified as primary risk factors.

CONCLUSION

The results of this study suggest that the majority high school baseball coaches implement group-based arm care exercise programs to prevent injury. Lack of confidence in the effectiveness and staffing limitations were major barriers to implementation of arm care programming. However, the responding coaches exhibited inconsistent risk factor awareness and dated injury prevention beliefs. Therefore, better educational collaboration between rehabilitation professionals and high school coaches regarding injury risk factors and preventative strategies is warranted.

LEVEL OF EVIDENCE

Level 3.

Pioglitazone does not synergize with mirabegron to increase beige fat or further improve glucose metabolism

BACKGROUND

Beige and brown adipose tissue (BAT) are associated with improved metabolic homeostasis. We recently reported that the β₃-adrenergic receptor agonist mirabegron induced beige adipose tissue in obese insulin-resistant subjects, and this was accompanied by improved glucose metabolism. Here we evaluated pioglitazone treatment with a combination pioglitazone and mirabegron treatment and compared these with previously published data evaluating mirabegron treatment alone. Both drugs were used at FDA-approved dosages.

METHODS

We measured BAT by PET CT scans, measured beige adipose tissue by immunohistochemistry, and comprehensively characterized glucose and lipid homeostasis and insulin sensitivity by euglycemic clamp and oral glucose tolerance tests. Subcutaneous white adipose tissue, muscle fiber type composition and capillary density, lipotoxicity, and systemic inflammation were evaluated by immunohistochemistry, gene expression profiling, mass spectroscopy, and ELISAs.

RESULTS

Treatment with pioglitazone or the combination of pioglitazone and mirabegron increased beige adipose tissue protein marker expression and improved insulin sensitivity and glucose homeostasis, but neither treatment induced BAT in these obese subjects. When the magnitude of the responses to the treatments was evaluated, mirabegron was found to be the most effective at inducing beige adipose tissue. Although monotherapy with either mirabegron or pioglitazone induced adipose beiging, combination treatment resulted in less beiging than either alone. The 3 treatments also had different effects on muscle fiber type switching and capillary density.

CONCLUSION

The addition of pioglitazone to mirabegron treatment does not enhance beiging or increase BAT in obese insulin-resistant research participants.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02919176.

FUNDING

NIH DK112282 and P20GM103527 and Clinical and Translational Science Awards grant UL1TR001998.

Tools for Selecting Working Correlation Structures When Using Weighted GEE to Model Longitudinal Survey Data

Weighted generalized estimating equations (GEE) are popular for the marginal analysis of longitudinal survey data. This popularity is due to the ability of these estimating equations to provide consistent regression parameter estimates and corresponding standard error estimates as long as the population mean and survey weights are correctly specified. Although the data analyst must incorporate a working correlation structure within the weighted GEE, this structure need not be correctly specified. However, accurate modeling of this structure has the potential to improve regression parameter estimation, i.e. reduce standard errors, and therefore the selection of a working correlation structure for use within GEE has received considerable attention in standard longitudinal data analysis settings. In this manuscript, we describe how correlation selection criteria can be extended for use with weighted GEE in the context of analyzing longitudinal survey data. Importantly, we provide and demonstrate an R function that we have created for such analyses. Furthermore, we discuss correlation selection in the context of using existing software which does not have this explicit capability. The methods are demonstrated via the use of data from a real survey in which we are interested in the mean number of falls that elderly individuals in a specific subpopulation experience over time.

Current Concepts in Arm Care Exercise Programs and Injury Risk Reduction in Adolescent Baseball Players: A Clinical Review

CONTEXT

Awareness of important injury risk factors associated with excessive pitching volume has been highlighted in the literature, but injury rates remain high. Shoulder pain in baseball players is associated with various changes in musculoskeletal movements, which presents as measurable impairments throughout the kinetic chain. Baseball coaches and rehabilitation professionals have utilized exercise programs targeting strength and flexibility of the throwing arm to prevent injuries. The purpose of this review is to summarize the current evidence regarding the effectiveness of arm care exercise programs in reducing upper extremity injury rates in adolescent baseball players.

EVIDENCE ACQUISITION

A search of electronic databases, including CINAHL with full text, MEDLINE, and SPORTDiscus was conducted to retrieve available articles in English from the years 2010 through 2020. The search terms injury prevention, exercise, and adolescent baseball were used.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 4.

RESULTS

Improving shoulder internal rotation range of motion by stretching the posterior shoulder muscles daily was associated with a 36% risk reduction of shoulder and elbow injuries. Group-based arm care exercise programs that target multiple musculoskeletal impairments demonstrated an approximately 50% reduced risk of elbow injury.

CONCLUSION

For adolescent baseball players, arm care injury prevention programs focusing on important musculoskeletal impairments are effective at reducing injury incidence rates. Multimodal injury prevention programs that improve multiple musculoskeletal impairments are more comprehensive and may result in better injury reduction than programs focusing on a singular impairment.

Response to first dose of inhaled albuterol in mechanically ventilated preterm infants

BACKGROUND

Bronchodilator responses among preterm infants are heterogeneous. Bedside measurements may identify responders.

STUDY DESIGN

Respiratory measurements (Resistance, Compliance, FiO₂) and pulse oximetry (SpO₂) patterns were downloaded from infants <30 weeks gestational age during the first 2 months of life. Mechanically ventilated infants who received albuterol were included (n = 33). Measurements were compared before and after first albuterol. Secondary analyses assessed subsequent doses.

RESULTS

Median gestation and birthweight were 25 3/7 weeks and 730 g, respectively. Mean Resistance decreased post-albuterol (p = 0.007). Sixty-eight percent of infants were responders based on decreased Resistance. Compliance and FiO₂ did not significantly differ. Percent time in hypoxemia (SpO₂< 85%) decreased post albuterol (p < 0.02). In responders, Resistance changes diminished with subsequent administration (all p = 0.01).

CONCLUSIONS

Ventilator resistance decreased in two-thirds of preterm infants, consistent with studies that utilized formal pulmonary function testing. Albuterol had a variable effect on delivered FiO₂; however, hypoxemia may be useful in evaluating albuterol response.

The HEALing (Helping to End Addiction Long-term SM) Communities Study: Protocol for a cluster randomized trial at the community level to reduce opioid overdose deaths through implementation of an integrated set of evidence-based practices

BACKGROUND

Opioid overdose deaths remain high in the U.S. Despite having effective interventions to prevent overdose deaths, there are numerous barriers that impede their adoption. The primary aim of the HEALing Communities Study (HCS) is to determine the impact of an intervention consisting of community-engaged, data-driven selection, and implementation of an integrated set of evidence-based practices (EBPs) on reducing opioid overdose deaths.

METHODS

The HCS is a four year multi-site, parallel-group, cluster randomized wait-list controlled trial. Communities (n = 67) in Kentucky, Massachusetts, New York and Ohio are randomized to active intervention (Wave 1), which starts the intervention in Year 1 or the wait-list control (Wave 2), which starts the intervention in Year 3. The HCS will test a conceptually driven framework to assist communities in selecting and adopting EBPs with three components: 1) a community engagement strategy with local coalitions to guide and implement the intervention; 2) a compendium of EBPs coupled with technical assistance; and 3) a series of communication campaigns to increase awareness and demand for EBPs and reduce stigma. An implementation science framework guides the intervention and allows for examination of the multilevel contexts that promote or impede adoption and expansion of EBPs. The primary outcome, number of opioid overdose deaths, will be compared between Wave 1 and Wave 2 communities during Year 2 of the intervention for Wave 1. Numerous secondary outcomes will be examined.

DISCUSSION

The HCS is the largest community-based implementation study in the field of addiction with an ambitious goal of significantly reducing fatal opioid overdoses.

Effect of Dry Needling on Spinal Reflex Excitability and Postural Control in Individuals With Chronic Ankle Instability

OBJECTIVE

The purpose of this study was to compare postural control and neurophysiologic components of balance after dry needling of the fibularis longus between individuals with chronic ankle instability (CAI) and a healthy control group.

METHODS

This quasi-experimental university-laboratory study included 50 adult volunteers-25 with CAI (16 female, 9 male; age: 26 ± 9.42 years; height: 173.12 ± 9.85 cm; weight: 79.27 ± 18 kg) and 25 healthy controls (15 female, 10 male; age: 25.8 ± 5.45 years; height: 169.47 ± 9.43 cm; weight: 68.47 ± 13 kg). Participants completed the Star Excursion Balance Test (SEBT), single-leg balance, and assessment of spinal reflex excitability before and after a single treatment of dry needling to the fibularis longus. The anterior, posterolateral, and posteromedial directions of the SEBT were randomized, and reach distances were normalized to a percentage of leg length. A composite SEBT score was calculated by averaging the normalized scores. Postural control was assessed in single-limb stance on a force plate through time-to-boundary measurements in eyes-open and eyes-closed conditions. Fibularis longus and soleus spinal reflexes were obtained by providing electrical stimulation to the common fibular and tibial nerves with participants lying prone. A Group × Time analysis examined changes in performance, and effect sizes were calculated to assess significance.

RESULTS

Significant group × time interactions were identified for composite (P = .006) and posteromedial (P = .017) SEBT scores. Significant time effects for all directions of the SEBT, time to boundary with eyes open, and the mediolateral direction with eyes closed indicate improved postural control following treatment (P < .008). Within-group effect sizes for significant time effects ranged from small to large, indicating potential clinical utility.

CONCLUSION

Dry needling demonstrated immediate short-term improvement in measures of static and postural control in individuals with CAI as well as healthy controls.

Marginal quantile regression for longitudinal data analysis in the presence of time-dependent covariates

When observations are correlated, modeling the within-subject correlation structure using quantile regression for longitudinal data can be difficult unless a working independence structure is utilized. Although this approach ensures consistent estimators of the regression coefficients, it may result in less efficient regression parameter estimation when data are highly correlated. Therefore, several marginal quantile regression methods have been proposed to improve parameter estimation. In a longitudinal study some of the covariates may change their values over time, and the topic of time-dependent covariate has not been explored in the marginal quantile literature. As a result, we propose an approach for marginal quantile regression in the presence of time-dependent covariates, which includes a strategy to select a working type of time-dependency. In this manuscript, we demonstrate that our proposed method has the potential to improve power relative to the independence estimating equations approach due to the reduction of mean squared error.

Maintaining the validity of inference in small-sample stepped wedge cluster randomized trials with binary outcomes when using generalized estimating equations

Stepped wedge cluster trials are an increasingly popular alternative to traditional parallel cluster randomized trials. Such trials often utilize a small number of clusters and numerous time intervals, and these components must be considered when choosing an analysis method. A generalized linear mixed model containing a random intercept and fixed time and intervention covariates is the most common analysis approach. However, the sole use of a random intercept applies a constant intraclass correlation coefficient structure, which is an assumption that is likely to be violated given stepped wedge trials (SWTs) have multiple time intervals. Alternatively, generalized estimating equations (GEE) are robust to the misspecification of the working correlation structure, although it has been shown that small-sample adjustments to standard error estimates and the use of appropriate degrees of freedom are required to maintain the validity of inference when the number of clusters is small. In this article, we show, using an extensive simulation study based on a motivating example and a more general design, the use of GEE can maintain the validity of inference in small-sample SWTs with binary outcomes. Furthermore, we show which combinations of bias corrections to standard error estimates and degrees of freedom work best in terms of attaining nominal type I error rates.

The β3-adrenergic receptor agonist mirabegron improves glucose homeostasis in obese humans

BACKGROUNDBeige adipose tissue is associated with improved glucose homeostasis in mice. Adipose tissue contains β3-adrenergic receptors (β3-ARs), and this study was intended to determine whether the treatment of obese, insulin-resistant humans with the β3-AR agonist mirabegron, which stimulates beige adipose formation in subcutaneous white adipose tissue (SC WAT), would induce other beneficial changes in fat and muscle and improve metabolic homeostasis.METHODSBefore and after β3-AR agonist treatment, oral glucose tolerance tests and euglycemic clamps were performed, and histochemical analysis and gene expression profiling were performed on fat and muscle biopsies. PET-CT scans quantified brown adipose tissue volume and activity, and we conducted in vitro studies with primary cultures of differentiated human adipocytes and muscle.RESULTSThe clinical effects of mirabegron treatment included improved oral glucose tolerance (P < 0.01), reduced hemoglobin A1c levels (P = 0.01), and improved insulin sensitivity (P = 0.03) and β cell function (P = 0.01). In SC WAT, mirabegron treatment stimulated lipolysis, reduced fibrotic gene expression, and increased alternatively activated macrophages. Subjects with the most SC WAT beiging showed the greatest improvement in β cell function. In skeletal muscle, mirabegron reduced triglycerides, increased the expression of PPARγ coactivator 1 α (PGC1A) (P < 0.05), and increased type I fibers (P < 0.01). Conditioned media from adipocytes treated with mirabegron stimulated muscle fiber PGC1A expression in vitro (P < 0.001).CONCLUSIONMirabegron treatment substantially improved multiple measures of glucose homeostasis in obese, insulin-resistant humans. Since β cells and skeletal muscle do not express β3-ARs, these data suggest that the beiging of SC WAT by mirabegron reduces adipose tissue dysfunction, which enhances muscle oxidative capacity and improves β cell function.TRIAL REGISTRATIONClinicaltrials.gov NCT02919176.FUNDINGNIH: DK112282, P30GM127211, DK 71349, and Clinical and Translational science Awards (CTSA) grant UL1TR001998.

Impact of motor therapy with dynamic body-weight support on Functional Independence Measures in traumatic brain injury: An exploratory study

BACKGROUND:

Contemporary goals of rehabilitation after traumatic brain injury (TBI) aim to improve cognitive and motor function by applying concepts of neuroplasticity. This can be challenging to carry out in TBI patients with motor, balance, and cognitive impairments.

OBJECTIVE:

To determine whether use of dynamic body-weight support (DBWS) would allow safe administration of intensive motor therapy during inpatient rehabilitation and whether its use would yield greater improvement in functional recovery than standard-of-care (SOC) therapy in adults with TBI.

METHODS:

Data in this retrospective cohort study was collected from patients with TBI who receive inpatient rehabilitation incorporating DBWS (n = 6) and who received inpatient rehabilitation without DBWS (SOC, n = 6). The primary outcome measure was the change in Functional Independence Measures (FIM) scores from admission to discharge.

RESULTS:

There was significant improvement in total FIM scores at discharge compared to admission for both the DBWS (p = 0.001) and SOC (p = 0.005) groups. Overall, the DBWS group had greater improvement in total FIM score and FIM subscales compared to the SOC group.

CONCLUSIONS:

Our results suggest DBWS has the potential to allow a greater intensity of therapy during inpatient rehabilitation and yield better outcomes compared to SOC in patients with TBI.

Apnea in Preterm and Term Infants After Deep Sedation and General Anesthesia

OBJECTIVES

Determine the incidence of apnea in preterm and term infants after deep sedation (DS) compared with general anesthesia (GA).

METHODS

A retrospective chart review was performed on infants who underwent elective DS or GA from January 2008 to December 2013, were <60 weeks postmenstrual age if preterm or <50 weeks postmenstrual age if term, and were monitored for apnea as inpatients after DS or GA. Gestational age, postmenstrual age, chronologic age, anesthetic and sedative medications, procedure indication, and postsedation events were collected.

RESULTS

There were 61 DS encounters (24 preterm and 37 term) and 175 GA encounters (120 preterm and 55 term) that met inclusion criteria. No recorded apneic events in either preterm or term infants were recorded after DS. After GA, 1.7% of infants had apneic events (2.5% preterm and 0 term; P = .57 versus DS). All events occurred within 2 hours of monitoring in recovery.

CONCLUSIONS

None of the infants had apnea after DS. Rates from the literature would suggest that 2 to 6 of the preterm DS subjects should have experienced postsedation apnea. Sampled GA subjects had a rate of 2.5% in preterm infants exhibiting apnea after GA. Although the post-DS apnea rate is lower than what has been previously published, the small sample size and limitations of a retrospective design prevent us from directing a change in postsedation monitoring recommendations. However, we do support the need for prospective studies with strict monitoring criteria to reveal the true risk of post-DS apnea.

Risk Factors Affecting Length of Stay in Patients with Deep Neck Space Infection

OBJECTIVES

Analyze risk factors affecting length of stay (LOS) for patients presenting with deep neck space infections including care by medical versus surgical team.

METHODS

This is a retrospective chart review from January 2005 through May 2018 at the University of Kentucky analyzing factors related to deep neck space abscesses. Patients included adults >18 years old admitted for deep neck space infections undergoing surgical intervention. This study compared effects of treatment on a medical versus surgical service on LOS while accounting for patient confounders. Independent variables included age, gender, tobacco use, medical comorbidities, Charlson comorbidity index, American Society of Anesthesiology (ASA) classification, presence of drain, readmissions, and repeat surgical interventions. Univariate and multivariate analysis were performed.

RESULTS

One hundred sixty-three patients were included in the analysis. LOS was significantly longer for those on medicine services (P < .001). Patients on medicine services had a higher incidence of diabetes (P = .011), higher Charlson comorbidity score (P = .001), and higher incidence of repeat interventions (P = .005). Postoperative LOS remained lower for patients on a surgical service (P = .009) after adjusting for Charlson comorbidity scores. Presence of a drain or tobacco use was not significant between service management (P = .89; P = .63) or LOS (P = .366; P = .225).

CONCLUSION

Increased postoperative LOS was associated with age, diabetes, ASA class, Charlson comorbidity index, and repeat procedures. Patients on a medicine service had longer LOS and higher comorbidity indices. Patients had shorter hospital stays on surgical services after adjusting for comorbidity indices. Use of a drain or presence of tobacco use did not affect LOS.

LEVEL OF EVIDENCE

3 Laryngoscope, 130:2133-2137, 2020.

Absence of Motor-Evoked Potentials Does Not Predict Poor Recovery in Patients With Severe-Moderate Stroke: An Exploratory Analysis

Objective

To better understand the role of the presence or absence of motor-evoked potentials (MEPs) in predicting functional outcomes following a severe-moderate stroke.

Design

Retrospective exploratory analysis. We compared the effects of the stimulation condition (active or sham), MEP status (+ or −), and a combination of stimulation condition and MEP status on outcome. Within-group and between-group changes were assessed with longitudinal repeated measures analysis of variance and longitudinal repeated measures analysis of covariance, respectively. The proportions of participants who achieved minimal clinically important differences (MCIDs) for the main outcome measures were calculated.

Setting

University research laboratory within a rehabilitation hospital.

Participants

A total of 129 subjects with severe-moderate stroke-related motor impairments who participated in previous studies combining neuromodulation and motor training

Interventions

Neuromodulation (active or sham) and motor training.

Main Outcome Measures

Fugl-Meyer Assessment (FMA) and Action Research Arm Test (ARAT).

Results

When participants were grouped by stimulation condition or MEP status, all groups improved from baseline to immediate postintervention and follow-up evaluations (all P<.05). Analysis by stimulation condition and MEP status found that the MEP−/active group improved by 4.2 points on FMA (P<.0001) and 1.8 on ARAT (P=.003) post intervention. The MEP+/active group improved by 5.7 points on FMA (P<.0001) and 3.9 points on ARAT (P<.0001) post intervention. There were no between-group differences (P>.05). Regarding MCIDs, in the MEP−/active group, 14.5% of individuals reached MCID on FMA and 8.3% on ARAT post intervention. In the MEP+/active group, 33.3% of individuals reached MCID on FMA and 27.3% on ARAT post intervention.

Conclusion

As expected, the MEP+ group had the greatest improvement in motor function. However, it was shown that individuals without MEPs can also achieve meaningful changes, as reflected by MCID, when neuromodulation is paired with motor training. To our knowledge, this is the first study to differentiate the effects of neuromodulation by MEP status.

Effect of Rifaximin Treatment on Endotoxemia and Insulin Sensitivity in Humans

CONTEXT

The gut microbiome is a source of inflammatory factors such as lipopolysaccharide (LPS; endotoxin) that influence metabolic homeostasis. Rifaximin is a well-tolerated antibiotic that may reduce LPS.

OBJECTIVE

We sought to develop a method to accurately assess postprandial endotoxemia and to determine whether rifaximin treatment improves metabolic homeostasis in obese humans with metabolic syndrome.

DESIGN AND SETTING

Plasma LPS, adipose inflammation, glucose and lipid metabolism, and insulin sensitivity were evaluated in a clinical research setting.

PARTICIPANTS

Twelve obese human research participants with prediabetes or three features of metabolic syndrome participated.

INTERVENTION

The research participants were randomized to placebo control or rifaximin soluble solid dispersion (80 mg/d) treatment groups and treated for 12 weeks.

OUTCOME MEASURES

We evaluated changes in insulin sensitivity with a euglycemic clamp; changes in lipid and glucose metabolism with oral lipid and glucose tolerance tests; changes in plasma LPS during the lipid tolerance test; and changes in adipose tissue and systemic inflammation by measuring inflammatory cytokines.

RESULTS

Rifaximin treatment slightly worsened insulin sensitivity (P = 0.03), did not improve glucose or lipid homeostasis, and did not significantly improve adipose tissue inflammation. Our efforts to accurately assess plasma LPS using limulus amebocyte lysate assays revealed that the majority of LPS is masked from detection by limulus amebocyte lysate assays, but can be unmasked using a pretreatment step with protease. Unmasked LPS increases during the lipid tolerance test, but rifaximin treatment did not reduce this.

CONCLUSIONS

Rifaximin treatment did not lower plasma LPS or improve metabolic homeostasis in obese humans.

Chronicity of Stroke Does Not Affect Outcomes of Somatosensory Stimulation Paired With Task-Oriented Motor Training: A Secondary Analysis of a Randomized Controlled Trial

Objective

To determine whether chronicity influences outcomes of somatosensory stimulation paired with task-oriented motor training for participants with severe-to-moderate upper extremity hemiparesis.

Design

Spearman correlations were used to retrospectively analyze outcomes of a randomized trial.

Setting

University research laboratory at a rehabilitation hospital.

Participants

Adults, ranging between 3 and 12 months poststroke (N=55).

Interventions

About 18 sessions pairing either 2 hours of active (n=33) or sham (n=22) somatosensory stimulation with 4 hours of intensive task-oriented motor training.

Main Outcome Measures

The Wolf Motor Function Test (primary), Action Research Arm Test, Stroke Impact Scale, and Fugl-Meyer Assessment were collected as outcome measures. Analyses evaluated whether within-group chronicity correlated with pre-post changes on primary and secondary outcome measures of motor performance.

Results

Both groups exhibited improvements on all outcome measures. No significant correlations between chronicity poststroke and the amount of motor recovery were found.

Conclusion

Somatosensory stimulation improved motor recovery compared with sham treatment in cases of severe-to-moderate hemiparesis between 3 and 12 months poststroke; and the extent of recovery did not correlate with baseline levels of stroke chronicity. Future studies should investigate a wider period of inclusion, patterns of corticospinal reorganization, differences between cortical and subcortical strokes, and include long-term follow-up periods.

Influence of mini-screw diameter and loading conditions on static and dynamic assessments of bone-implant contact: An animal study

OBJECTIVES

The goal was to compare static versus dynamic bone-implant interface histology of mini-screws and to evaluate its relation to diameter and load.

SETTING AND SAMPLE POPULATION

Canine animal model.

MATERIAL AND METHODS

Custom-machined, titanium alloy (Ti6AI4V) mini-screws (n = 70) of 1.60, 2.00, 3.00 and 3.75 mm diameter were placed into edentulous sites in five skeletally mature beagle dogs. Using a split-mouth design, no load (NL) was applied to one side while a 2N load (L) was applied by calibrated coil springs on the other side. Intravenous bone labels were administered 21 and 7 days prior to sacrifice. Dogs were euthanized 90 days after screw placement. Bone sections were analysed under bright-field and epifluorescent light. The region of interest was defined as the bone within the threads of the screws. The following parameters were quantified: (a) Static-bone volume/tissue volume (BV/TV %) and bone-implant contact (BIC, %); (b) Dynamic-labelled bone/bone volume (LB/BV, %), and dynamic BIC (DBIC, %).

RESULTS

BV/TV ranged from 71.2% to 85.0% of the screw surface. BIC ranged from 45.7% to 55.4% of the screw surface and was not affected by diameter (P = 0.66). In contrast, the percentage of DBIC did not vary with the applied load (P = 0.41); however, it correlated significantly with the diameter of the screw (P = 0.001).

CONCLUSION

The percentage of DBIC that is actively remodelling increases with increasing diameter of the screw. Dynamic histomorphometry is more sensitive to detecting changes in bone-implant contact when compared to static measurements.

Novel application and validation of in vivo micro-CT to study bone modelling in 3D

OBJECTIVES

The aim is to highlight a novel three-dimensional (3D) imaging methodology using micro-CT scans to visualize and measure bone modelling in an animal model. In order to validate the new methodology, we compared the 3D imaging method to traditional two-dimensional (2D) histomorphometry to assess growth changes in the jaws of a rodent.

SETTING AND SAMPLE POPULATION

Rodent animal models.

MATERIAL AND METHODS

Eleven rats were obtained from a larger previously published study. Sixty undecalcified histological sections from the maxilla and corresponding high-resolution in vivo micro-CT reconstructions were obtained. Bone modelling changes on specific alveolar surfaces were measured using traditional histomorphometry. Measurements of bone growth were also obtained via 3D Slicer software from 3D micro-CT generated models from the same plane containing the histological images. Both qualitative and quantitative 3D methods were compared to traditional histological measurements. Quantitative agreement between methods was categorized as follows: poor (>150 μm), good (150-100 μm) and excellent (<100 μm).

RESULTS

Both qualitative (88.3%) and quantitative (86.7%) 3D measurements showed excellent agreement, when compared to histomorphometric measurements. Only 1.7% and 5% of the comparisons exhibited poor agreement (>150 μm) for qualitative and quantitative methods, respectively.

DISCUSSION

The new 3D superimposition method compares very favourably with traditional histology. It is likely that in the future, such methods will be used in studies of bone adaptation.

CONCLUSION

The 3D micro-CT qualitative and quantitative methods are reliable for measuring bone modelling changes and compare favourably to histology for the specific application described.

Socioemotional selectivity and psychological health in amyotrophic lateral sclerosis patients and caregivers: a longitudinal, dyadic analysis

Objective: Socioemotional selectivity theory predicts that as the end of life approaches, goals and resources that provide immediate, hedonic reward become more important than those that provide delayed rewards. This study tested whether these goal domains differentially affected psychological health in the context of marital dyads in which one partner had been diagnosed with amyotrophic lateral sclerosis (ALS), a life-limiting disease. Design: ALS patients (N = 102) being treated in three multidisciplinary clinics and their spouses (N = 100) reported their loneliness, financial worry and psychological health every 3 months for up to 18 months. Main Outcome Measure: Psychological health composite. Results: In multilevel dyadic models, patients and spouses had similar levels of financial worry and loneliness. Both patients and spouses had worse psychological health with higher loneliness, but only spouses had worse psychological health with higher financial worry. Significant interactions with age and disease severity indicated that older spouses were more affected by loneliness than were younger spouses, and patients with less severe disease were more affected by financial worry than patients with more severe disease. Conclusion: The results provide good support for socioemotional selectivity theory's implications for psychological health in a strong test of the theory.

A rodent model using skeletal anchorage and low forces for orthodontic tooth movement

INTRODUCTION

Nonhuman animal models have been used extensively to study orthodontic tooth movement (OTM). However, rodent models have disadvantages, including a reported reduction in bone volume during OTM. The purpose of this study was to determine the viability of a skeletal anchorage and the effect of low force (∼3 cN) on interradicular bone volume during OTM.

METHODS

Ninety Sprague-Dawley rats were divided into 5 time points. A miniscrew and a nickel titanium coil spring placed a load of 3 cN (experimental) or 0 cN (sham) on the maxillary first molar in a split-mouth design. Displacement of the first molar and bone volume/total volume (BV/TV) in the interradicular region were quantified.

RESULTS

The success rate of the miniscrew was 98.9% (89 out of 90). Linear and angular tooth movement increased steadily (mean 0.1 mm/wk, 0.48 mm at 40 days). BV/TV was significantly reduced between the tooth movement and non-tooth movement sides in the 3 cN group: by 13%, 23%, 15%, 23%, and 16% at 3, 7, 14, 28, and 40 days, respectively.

CONCLUSIONS

Our model resulted in efficient OTM without skeletal anchorage failure. BV/TV reduction was lower than in previous reports. This novel validated model is likely to be the basis for future studies.