Implementation of substance use screening in rural federally-qualified health center clinics identified high rates of unhealthy alcohol and cannabis use among adult primary care patients

BACKGROUND

Screening for substance use in rural primary care clinics faces unique challenges due to limited resources, high patient volumes, and multiple demands on providers. To explore the potential for electronic health record (EHR)-integrated screening in this context, we conducted an implementation feasibility study with a rural federally-qualified health center (FQHC) in Maine. This was an ancillary study to a NIDA Clinical Trials Network study of screening in urban primary care clinics (CTN-0062).

METHODS

Researchers worked with stakeholders from three FQHC clinics to define and implement their optimal screening approach. Clinics used the Tobacco, Alcohol, Prescription Medication, and Other Substance (TAPS) Tool, completed on tablet computers in the waiting room, and results were immediately recorded in the EHR. Adult patients presenting for annual preventive care visits, but not those with other visit types, were eligible for screening. Data were analyzed for the first 12 months following implementation at each clinic to assess screening rates and prevalence of reported unhealthy substance use, and documentation of counseling using an EHR-integrated clinical decision support tool, for patients screening positive for moderate-high risk alcohol or drug use.

RESULTS

Screening was completed by 3749 patients, representing 93.4% of those with screening-eligible annual preventive care visits, and 18.5% of adult patients presenting for any type of primary care visit. Screening was self-administered in 92.9% of cases. The prevalence of moderate-high risk substance use detected on screening was 14.6% for tobacco, 30.4% for alcohol, 10.8% for cannabis, 0.3% for illicit drugs, and 0.6% for non-medical use of prescription drugs. Brief substance use counseling was documented for 17.4% of patients with any moderate-high risk alcohol or drug use.

CONCLUSIONS

Self-administered EHR-integrated screening was feasible to implement, and detected substantial alcohol, cannabis, and tobacco use in rural FQHC clinics. Counseling was documented for a minority of patients with moderate-high risk use, possibly indicating a need for better support of primary care providers in addressing substance use. There is potential to broaden the reach of screening by offering it at routine medical visits rather than restricting to annual preventive care visits, within these and other rural primary care clinics.

A Brief Screening and Assessment Tool for Opioid Use in Adults: Results from a Validation Study of the Tobacco, Alcohol, Prescription Medication, and Other Substances Tool

OBJECTIVES

This secondary analysis evaluated opioid-specific validation results of the Tobacco, Alcohol, Prescription Medication, and Other Substances (TAPS) tool for screening in primary care.

METHODS

This study is a secondary data analysis of the TAPS validation study. Performance of the TAPS tool for screening for unhealthy opioid use (with a score of 1+ for heroin and/or prescription opioids representing a positive screen) was evaluated. Discriminative ability was examined in comparison with reference standard measures across the spectrum of unhealthy opioid use: timeline follow-back with and without oral fluid testing identifying past-month use and the modified Composite International Diagnostic Interview for past-year problem use, opioid use disorder (OUD), and moderate-severe OUD.

RESULTS

In a sample of 2000 primary care patients, 114 screened positive for opioids on the TAPS tool. With a TAPS cutoff equal to 1+, the TAPS accurately identified past-month use, problem use, any OUD, and moderate-severe OUD (sensitivities = 68%-85%, specificities = 97%-98%, area under the curve = 0.80-0.91). When past-month use was expanded to include timeline follow-back with oral fluid testing, accuracy declined (52% sensitivity [95% confidence interval, 43%-60%], 98% specific [95% confidence interval, 97%-98%]).

CONCLUSIONS

While further testing in a larger population sample may be warranted, given their brevity, simplicity, and accuracy when self-administered, the TAPS opioid items can be used in primary care settings for a spectrum of unhealthy opioid use; however, self-disclosure remains an issue in primary care settings.

Buprenorphine physician-pharmacist collaboration in the management of patients with opioid use disorder: results from a multisite study of the National Drug Abuse Treatment Clinical Trials Network

BACKGROUND AND AIMS

Physician and pharmacist collaboration may help address the shortage of buprenorphine-waivered physicians and improve care for patients with opioid use disorder (OUD). This study investigated the feasibility and acceptability of a new collaborative care model involving buprenorphine-waivered physicians and community pharmacists.

DESIGN

Nonrandomized, single-arm, open-label feasibility trial.

SETTING

Three office-based buprenorphine treatment (OBBT) clinics and three community pharmacies in the United States.

PARTICIPANTS

Six physicians, six pharmacists, and 71 patients aged ≥18 years with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) OUD on buprenorphine maintenance.

INTERVENTION

After screening, eligible patients' buprenorphine care was transferred from their OBBT physician to a community pharmacist for 6 months.

MEASUREMENTS

Primary outcomes included recruitment, treatment retention and adherence, and opioid use. Secondary outcomes were intervention fidelity, pharmacists' use of prescription drug monitoring program (PDMP), participant safety, and satisfaction with treatment delivery.

FINDINGS

A high proportion (93.4%, 71/76) of eligible participants enrolled into the study. There were high rates of treatment retention (88.7%) and adherence (95.3%) at the end of the study. The proportion of opioid-positive urine drug screens (UDSs) among complete cases (i.e. those with all six UDSs collected during 6 months) at month 6 was (4.9%, 3/61). Intervention fidelity was excellent. Pharmacists used PDMP at 96.8% of visits. There were no opioid-related safety events. Over 90% of patients endorsed that they were "very satisfied with their experience and the quality of treatment offered," that "treatment transfer from physician's office to the pharmacy was not difficult at all," and that "holding buprenorphine visits at the same place the medication is dispensed was very or extremely useful/convenient." Similarly, positive ratings of satisfaction were found among physicians/pharmacists.

CONCLUSIONS

A collaborative care model for people with opioid use disorder that involves buprenorphine-waivered physicians and community pharmacists appears to be feasible to operate in the United States and have high acceptability to patients.

Comparison of Methods for Alcohol and Drug Screening in Primary Care Clinics

IMPORTANCE

Guidelines recommend that adult patients receive screening for alcohol and drug use during primary care visits, but the adoption of screening in routine practice remains low. Clinics frequently struggle to choose a screening approach that is best suited to their resources, workflows, and patient populations.

OBJECTIVE

To evaluate how to best implement electronic health record (EHR)-integrated screening for substance use by comparing commonly used screening methods and examining their association with implementation outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This article presents the outcomes of phases 3 and 4 of a 4-phase quality improvement, implementation feasibility study in which researchers worked with stakeholders at 6 primary care clinics in 2 large urban academic health care systems to define and implement their optimal screening approach. Site A was located in New York City and comprised 2 clinics, and site B was located in Boston, Massachusetts, and comprised 4 clinics. Clinics initiated screening between January 2017 and October 2018, and 93 114 patients were eligible for screening for alcohol and drug use. Data used in the analysis were collected between January 2017 and October 2019, and analysis was performed from July 13, 2018, to March 23, 2021.

INTERVENTIONS

Clinics integrated validated screening questions and a brief counseling script into the EHR, with implementation supported by the use of clinical champions (ie, clinicians who advocate for change, motivate others, and use their expertise to facilitate the adoption of an intervention) and the training of clinic staff. Clinics varied in their screening approaches, including the type of visit targeted for screening (any visit vs annual examinations only), the mode of administration (staff-administered vs self-administered by the patient), and the extent to which they used practice facilitation and EHR usability testing.

MAIN OUTCOMES AND MEASURES

Data from the EHRs were extracted quarterly for 12 months to measure implementation outcomes. The primary outcome was screening rate for alcohol and drug use. Secondary outcomes were the prevalence of unhealthy alcohol and drug use detected via screening, and clinician adoption of a brief counseling script.

RESULTS

Patients of the 6 clinics had a mean (SD) age ranging from 48.9 (17.3) years at clinic B2 to 59.1 (16.7) years at clinic B3, were predominantly female (52.4% at clinic A1 to 64.6% at clinic A2), and were English speaking. Racial diversity varied by location. Of the 93,114 patients with primary care visits, 71.8% received screening for alcohol use, and 70.5% received screening for drug use. Screening at any visit (implemented at site A) in comparison with screening at annual examinations only (implemented at site B) was associated with higher screening rates for alcohol use (90.3%-94.7% vs 24.2%-72.0%, respectively) and drug use (89.6%-93.9% vs 24.6%-69.8%). The 5 clinics that used a self-administered screening approach had a higher detection rate for moderate- to high-risk alcohol use (14.7%-36.6%) compared with the 1 clinic that used a staff-administered screening approach (1.6%). The detection of moderate- to high-risk drug use was low across all clinics (0.5%-1.0%). Clinics with more robust practice facilitation and EHR usability testing had somewhat greater adoption of the counseling script for patients with moderate-high risk alcohol or drug use (1.4%-12.5% vs 0.1%-1.1%).

CONCLUSIONS AND RELEVANCE

In this quality improvement study, EHR-integrated screening was feasible to implement in all clinics and unhealthy alcohol use was detected more frequently when self-administered screening was used at any primary care visit. The detection of drug use was low at all clinics, as was clinician adoption of counseling. These findings can be used to inform the decision-making of health care systems that are seeking to implement screening for substance use.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02963948.

Bupropion and Naltrexone in Methamphetamine Use Disorder

BACKGROUND

The use of naltrexone plus bupropion to treat methamphetamine use disorder has not been well studied.

METHODS

We conducted this multisite, double-blind, two-stage, placebo-controlled trial with the use of a sequential parallel comparison design to evaluate the efficacy and safety of extended-release injectable naltrexone (380 mg every 3 weeks) plus oral extended-release bupropion (450 mg per day) in adults with moderate or severe methamphetamine use disorder. In the first stage of the trial, participants were randomly assigned in a 0.26:0.74 ratio to receive naltrexone-bupropion or matching injectable and oral placebo for 6 weeks. Those in the placebo group who did not have a response in stage 1 underwent rerandomization in stage 2 and were assigned in a 1:1 ratio to receive naltrexone-bupropion or placebo for an additional 6 weeks. Urine samples were obtained from participants twice weekly. The primary outcome was a response, defined as at least three methamphetamine-negative urine samples out of four samples obtained at the end of stage 1 or stage 2, and the weighted average of the responses in the two stages is reported. The treatment effect was defined as the between-group difference in the overall weighted responses.

RESULTS

A total of 403 participants were enrolled in stage 1, and 225 in stage 2. In the first stage, 18 of 109 participants (16.5%) in the naltrexone-bupropion group and 10 of 294 (3.4%) in the placebo group had a response. In the second stage, 13 of 114 (11.4%) in the naltrexone-bupropion group and 2 of 111 (1.8%) in the placebo group had a response. The weighted average response across the two stages was 13.6% with naltrexone-bupropion and 2.5% with placebo, for an overall treatment effect of 11.1 percentage points (Wald z-test statistic, 4.53; P<0.001). Adverse events with naltrexone-bupropion included gastrointestinal disorders, tremor, malaise, hyperhidrosis, and anorexia. Serious adverse events occurred in 8 of 223 participants (3.6%) who received naltrexone-bupropion during the trial.

CONCLUSIONS

Among adults with methamphetamine use disorder, the response over a period of 12 weeks among participants who received extended-release injectable naltrexone plus oral extended-release bupropion was low but was higher than that among participants who received placebo. (Funded by the National Institute on Drug Abuse and others; ADAPT-2 ClinicalTrials.gov number, NCT03078075.).

Effect of Oral Valproic Acid vs Placebo for Vision Loss in Patients With Autosomal Dominant Retinitis Pigmentosa: A Randomized Phase 2 Multicenter Placebo-Controlled Clinical Trial

Importance

There are no approved drug treatments for autosomal dominant retinitis pigmentosa, a relentlessly progressive cause of adult and childhood blindness.

Objectives

To evaluate the potential efficacy and assess the safety of orally administered valproic acid (VPA) in the treatment of autosomal dominant retinitis pigmentosa.

Design, Setting, and Participants

Multicenter, phase 2, prospective, interventional, placebo-controlled, double-masked randomized clinical trial. The study took place in 6 US academic retinal degeneration centers. Individuals with genetically characterized autosomal dominant retinitis pigmentosa were randomly assigned to receive treatment or placebo for 12 months. Analyses were intention-to-treat.

Interventions

Oral VPA 500 mg to 1000 mg daily for 12 months or placebo.

Main Outcomes and Measures

The primary outcome measure was determined prior to study initiation as the change in visual field area (assessed by the III4e isopter, semiautomated kinetic perimetry) between baseline and month 12.

Results

The mean (SD) age of the 90 participants was 50.4 (11.6) years. Forty-four (48.9%) were women, 87 (96.7%) were white, and 79 (87.8%) were non-Hispanic. Seventy-nine participants (87.8%) completed the study (42 [95.5%] received placebo and 37 [80.4%] received VPA). Forty-two (46.7%) had a rhodopsin mutation. Most adverse events were mild, although 7 serious adverse events unrelated to VPA were reported. The difference between the VPA and placebo arms for mean change in the primary outcome was -150.43 degree2 (95% CI, -290.5 to -10.03; P = .035).

Conclusions and Relevance

This negative value indicates that the VPA arm had worse outcomes than the placebo group. This study brings to light the key methodological considerations that should be applied to the rigorous evaluation of treatments for these conditions. This study does not provide support for the use of VPA in the treatment of autosomal dominant retinitis pigmentosa.

Trial Registration

ClinicalTrials.gov Identifier: NCT01233609.

A randomized placebo-controlled trial of N-acetylcysteine for cannabis use disorder in adults

BACKGROUND

Cannabis use disorder (CUD) is a prevalent and impairing condition, and established psychosocial treatments convey limited efficacy. In light of recent findings supporting the efficacy of N-acetylcysteine (NAC) for CUD in adolescents, the objective of this trial was to evaluate its efficacy in adults.

METHODS

In a 12-week double-blind randomized placebo-controlled trial, treatment-seeking adults ages 18-50 with CUD (N=302), enrolled across six National Drug Abuse Treatment Clinical Trials Network-affiliated clinical sites, were randomized in a 1:1 ratio to a 12-week course of NAC 1200mg (n=153) or placebo (n=149) twice daily. All participants received contingency management (CM) and medical management. The primary efficacy measure was the odds of negative urine cannabinoid tests during treatment, compared between NAC and placebo participants.

RESULTS

There was not statistically significant evidence that the NAC and placebo groups differed in cannabis abstinence (odds ratio=1.00, 95% confidence interval 0.63-1.59, p=0.984). Overall, 22.3% of urine cannabinoid tests in the NAC group were negative, compared with 22.4% in the placebo group. Many participants were medication non-adherent; exploratory analysis within medication-adherent subgroups revealed no significant differential abstinence outcomes by treatment group.

CONCLUSIONS

In contrast with prior findings in adolescents, there is no evidence that NAC 1200mg twice daily plus CM is differentially efficacious for CUD in adults when compared to placebo plus CM. This discrepant finding between adolescents and adults with CUD may have been influenced by differences in development, cannabis use profiles, responses to embedded behavioral treatment, medication adherence, and other factors.

Identifying substance misuse in primary care: TAPS Tool compared to the WHO ASSIST

BACKGROUND

There is a need for screening and brief assessment instruments to identify primary care patients with substance use problems. This study's aim was to examine the performance of a two-step screening and brief assessment instrument, the TAPS Tool, compared to the WHO ASSIST.

METHODS

Two thousand adult primary care patients recruited from five primary care clinics in four Eastern US states completed the TAPS Tool followed by the ASSIST. The ability of the TAPS Tool to identify moderate- and high-risk use scores on the ASSIST was examined using sensitivity and specificity analyses.

RESULTS

The interviewer and self-administered computer tablet versions of the TAPS Tool generated similar results. The interviewer-administered version (at cut-off of 2), had acceptable sensitivity and specificity for high-risk tobacco (0.90 and 0.77) and alcohol (0.87 and 0.80) use. For illicit drugs, sensitivities were >0.82 and specificities >0.92. The TAPS (at a cut-off of 1) had good sensitivity and specificity for moderate-risk tobacco use (0.83 and 0.97) and alcohol (0.83 and 0.74). Among illicit drugs, sensitivity was acceptable for moderate-risk of marijuana (0.71), while it was low for all other illicit drugs and non-medical use of prescription medications. Specificities were 0.97 or higher for all illicit drugs and prescription medications.

CONCLUSIONS

The TAPS Tool identified adult primary care patients with high-risk ASSIST scores for all substances as well moderate-risk users of tobacco, alcohol, and marijuana, although it did not perform well in identifying patients with moderate-risk use of other drugs or non-medical use of prescription medications. The advantages of the TAPS Tool over the ASSIST are its more limited number of items and focus solely on substance use in the past 3months.

Performance of the Tobacco, Alcohol, Prescription Medication, and Other Substance Use (TAPS) Tool for Substance Use Screening in Primary Care Patients

BACKGROUND

Substance use, a leading cause of illness and death, is underidentified in medical practice.

OBJECTIVE

The Tobacco, Alcohol, Prescription medication, and other Substance use (TAPS) tool was developed to address the need for a brief screening and assessment instrument that includes all commonly used substances and fits into clinical workflows. The goal of this study was to assess the performance of the TAPS tool in primary care patients.

DESIGN

Multisite study, conducted within the National Drug Abuse Treatment Clinical Trials Network, comparing the TAPS tool with a reference standard measure. (ClinicalTrials.gov: NCT02110693).

SETTING

5 adult primary care clinics.

PARTICIPANTS

2000 adult patients consecutively recruited from clinic waiting areas.

MEASUREMENTS

Interviewer- and self-administered versions of the TAPS tool were compared with a reference standard, the modified World Mental Health Composite International Diagnostic Interview (CIDI), which measures problem use and substance use disorder (SUD).

RESULTS

Interviewer- and self-administered versions of the TAPS tool had similar diagnostic characteristics. For identifying problem use (at a cutoff of 1+), the TAPS tool had a sensitivity of 0.93 (95% CI, 0.90 to 0.95) and specificity of 0.87 (CI, 0.85 to 0.89) for tobacco and a sensitivity of 0.74 (CI, 0.70 to 0.78) and specificity of 0.79 (CI, 0.76 to 0.81) for alcohol. For problem use of illicit and prescription drugs, sensitivity ranged from 0.82 (CI, 0.76 to 0.87) for marijuana to 0.63 (CI, 0.47 to 0.78) for sedatives; specificity was 0.93 or higher. For identifying any SUD (at a cutoff of 2+), sensitivity was lower.

LIMITATIONS

The low prevalence of some drug classes led to poor precision in some estimates. Research assistants were not blinded to participants' TAPS tool responses when they administered the CIDI.

CONCLUSION

In a diverse population of adult primary care patients, the TAPS tool detected clinically relevant problem substance use. Although it also may detect tobacco, alcohol, and marijuana use disorders, further refinement is needed before it can be recommended broadly for SUD screening.

PRIMARY FUNDING SOURCE

National Institute on Drug Abuse.

Cystatin C Is Associated with the Extent and Characteristics of Coronary Atherosclerosis in Patients with Preserved Renal Function

Cystatin C (CysC), an endogenous inhibitor of cysteine proteases and a sensitive and accurate marker of renal function, is associated with the severity of coronary atherosclerosis assessed by angiography and future cardiovascular events according to previous studies. We aimed to evaluate the association between CysC levels and coronary plaque volume, composition and phenotype assessed by intravascular ultrasound and intravascular ultrasound-derived virtual histology in patients with preserved renal function. Forty-four patients with angiographically documented coronary artery disease and complete intravascular imaging were included in the study. Patients were categorized into tertiles by CysC levels. Subjects in the high CysC tertile had significantly higher mean plaque burden (48.0 % ± 6.9 vs. 42.8 % ± 7.4, P = 0.029), lower mean lumen area (8.1 mm2 ± 1.7 vs. 9.9 mm2 ± 3.1, P = 0.044) and a higher number of 5-mm vessel segments with minimum lumen area < 4 mm2 (17.9 ± 18.9 vs. 6.8 ± 11.7, P = 0.021) compared to patients in the lower tertiles. In addition, CysC levels demonstrated significant positive correlation with the mean plaque burden (r = 0.35, P = 0.021). Neither relative, nor absolute plaque components differed significantly according to CysC tertiles. The Liverpool Active Plaque Score was significantly higher in the high CysC tertile patients (0.91 ± 1.0 vs. 0.18 ± 0.92, P = 0.02). In conclusion, our study demonstrated a significant association of increased CysC levels with more advanced coronary artery disease and higher risk plaque phenotype in patients with preserved renal function.

Internet-delivered treatment for substance abuse: a multisite randomized controlled trial

OBJECTIVE

Computer-delivered interventions have the potential to improve access to quality addiction treatment care. The objective of this study was to evaluate the effectiveness of the Therapeutic Education System (TES), an Internet-delivered behavioral intervention that includes motivational incentives, as a clinician-extender in the treatment of substance use disorders.

METHOD

Adult men and women (N=507) entering 10 outpatient addiction treatment programs were randomly assigned to receive 12 weeks of either treatment as usual (N=252) or treatment as usual plus TES, with the intervention substituting for about 2 hours of standard care per week (N=255). TES consists of 62 computerized interactive modules covering skills for achieving and maintaining abstinence, plus prize-based motivational incentives contingent on abstinence and treatment adherence. Treatment as usual consisted of individual and group counseling at the participating programs. The primary outcome measures were abstinence from drugs and heavy drinking (measured by twice-weekly urine drug screens and self-report) and time to dropout from treatment.

RESULTS

Compared with patients in the treatment-as-usual group, those in the TES group had a lower dropout rate (hazard ratio=0.72, 95% CI=0.57, 0.92) and a greater abstinence rate (odds ratio=1.62, 95% CI=1.12, 2.35). This effect was more pronounced among patients who had a positive urine drug or breath alcohol screen at study entry (N=228) (odds ratio=2.18, 95% CI=1.30, 3.68).

CONCLUSIONS

Internet-delivered interventions such as TES have the potential to expand access and improve addiction treatment outcomes. Additional research is needed to assess effectiveness in non-specialty clinical settings and to differentiate the effects of the community reinforcement approach and contingency management components of TES.

Prediction of coronary vessel involvement on the basis of atherosclerosis risk factor analysis

The prediction of coronary vessel involvement by means of noninvasive tests is one of the fundamental objectives of preventive cardiology. This review describes the current possibilities of coronary vessel involvement prediction by means of ultrasonographic examination of carotid arteries, analysis of polymorphisms in the genes encoding enzymes responsible for production of nitric oxide and carbon monoxide and assessment of levels of certain proinflammatory cytokines. In the presented work these noninvasive markers are correlated with the extent of coronary vessel involvement as assessed by coronary angiography, intravascular ultrasound and virtual histology (Fig. 5, Ref. 40).

Generation of donor-specific anti-human leukocyte antigen antibodies after the transplantation of a fully matched kidney allograft and its impact on the selection of a subsequent renal regraft: a case report

Detection of anti-human leukocyte antigen (HLA) antibodies and identification of their specificities represent important tasks for patients awaiting kidney allografts. Regarding patients immunized by pregnancies, transfusions, or previous transplantations of solid organs, the immunization status must be observed carefully because grafting them with HLA phenotypes recognized by their antibodies represents the main cause for hyper-acute or acute rejection episodes, often leading to transplant loss. A 10-year-old patient with end-stage renal insufficiency of HLA type A3, 25; B8, 18, (Bw6); Cw7,12; DR15,17; DR51,52; DQ2,6 received a deceased donor graft showing no HLA mismatch in 1998. It lost function after 8 years, resulting in the patient's re-entry onto the waiting list for kidney transplantation in 2006. Antibody screening detected anti-HLA-A25, A26, A34, and A66 (broad A10) antibodies using various techniques (DynaChip, Single Antigen enzyme-linked immunosorbent assay [ELISA]). Additionally, a kidney offer expressing the HLA-A25 phenotype was not acceptable for the patient due to a positive complement-dependent cytotoxicity assay (CDC)-based cross-match. The question arose whether this reactivity might be due to auto-reactive antibodies directed against the HLA-A25 phenotype. However, no auto-reactive antibodies were detectable using either the CDC-based or the antibody monitoring system-ELISA-based cross-match assays. Consequently the patient was re-examined at high resolution showing the rare HLA-A*25:14 genotype. This case showed that rare alleles may result in allele-specific antibodies directed against the common variants, thus leading to unexpected positive cross-match results against apparently matched allografts.

Genetic variants in haem oxygenase-1 and endothelial nitric oxide synthase influence the extent and evolution of coronary artery atherosclerosis

The genetic basis for atherosclerosis development and progression is poorly characterized. We aimed to assess the relationship between endothelial nitric oxide synthase (ENOS) 894 G/T, haem oxygenase-1 (HO1) dinucleotide-length promoter polymorphisms and coronary artery atherosclerotic invol vement and its changes during statin therapy. Coronary angiography, intravascular ultrasound (IVUS), IVUS-derived virtual histology (VH) and genetic polymorphism analysis were performed at study entry. Patients were randomized 1:1 to standard or aggressive hypolipidaemic treatment, and a follow-up evaluation was performed after twelve months. Plaque magnitude was significantly higher in carriers of HO1 risk variants when compared with carriers of the protective variants (< 25 GT repeats). Similarly, the total coronary atherosclerotic burden was significantly greater in HO1 risk variant carriers than in HO1 protective variant carriers. Both parameters did not differ with respect to the ENOS genotype. A higher prevalence of thin-cap fibroatheroma (TCFA) in HO1 risk variant carriers was observed, compared with the HO1 protective variant carriers. The prevalence of TCFA was not influenced by the ENOS genotype. Baseline plaque composition did not differ significantly with respect to both polymorphisms. Significant interactions between plaque composition changes and ENOS and HO1 genotypes were observed during statin treatment. In conclusion, the protective HO1 promoter polymorphism correlates with a lower coronary artery plaque burden, whereas the protective ENOS 894 G/T polymorphism seems to favourably influence changes of coronary artery plaque composition during statin therapy, but has no significant correlation to the magnitude of coronary atherosclerosis.

Clinical trial: phase 2 study of lubiprostone for irritable bowel syndrome with constipation

BACKGROUND

Analyses of a trial in constipated patients indicated that lubiprostone may be an effective treatment for irritable bowel syndrome with constipation.

AIM

To assess the efficacy and safety of three lubiprostone doses for irritable bowel syndrome with constipation.

METHODS

195 irritable bowel syndrome with constipation patients received daily doses of 16 [8 microg twice daily (b.d.)], 32 (16 microg b.d.) or 48 microg (24 microg b.d.) lubiprostone or placebo b.d. for 3 months. Gastrointestinal parameters were recorded in diaries daily by patients.

RESULTS

After 1 month, lubiprostone showed significantly greater improvements in mean abdominal discomfort/pain scores vs. placebo (P = 0.023). After 2 months, all lubiprostone groups showed significantly greater improvements in mean abdominal discomfort/pain scores (P < or = 0.039). After 3 months of treatment, the improvement in each lubiprostone arm was greater than placebo, but the test for trend was no longer significant. Treatment with lubiprostone showed significantly higher rates of gastrointestinal adverse events (P = 0.020), especially diarrhoea and nausea.

CONCLUSION

Lubiprostone significantly improved gastrointestinal symptoms of irritable bowel syndrome with constipation at all doses. Higher doses of lubiprostone, especially the 48 microg/day group, were associated with more gastrointestinal adverse events. From these data, the 16 microg/day dose demonstrated the optimal combination of efficacy and safety. These results warrant further study of lubiprostone for treatment of irritable bowel syndrome with constipation patients.

A novel HLA-A*0119 allele of a Caucasian family containing a mutation in a highly conserved region

A novel human leucocyte antigen (HLA)-A (HLA-A*0119) allele has been identified in two individuals of a Caucasian family from Middle Europe using a single-allele-specific sequencing strategy. This allele is identical to the HLA-A*0101 allele except for one point mutation in the highly conserved codon 92 (TCT --> GCT) resulting in an amino acid change from serine to alanine.

Comparison of left anterior descending coronary artery hemodynamics before and after angioplasty

Coronary artery disease (CAD) is characterized by the progression of atherosclerosis, a complex pathological process involving the initiation, deposition, development, and breakdown of the plaque. The blood flow mechanics in arteries play a critical role in the targeted locations and progression of atherosclerotic plaque. In coronary arteries with motion during the cardiac contraction and relaxation, the hemodynamic flow field is substantially different from the other arterial sites with predilection of atherosclerosis. In this study, our efforts focused on the effects of arterial motion and local geometry on the hemodynamics of a left anterior descending (LAD) coronary artery before and after clinical intervention to treat the disease. Three-dimensional (3D) arterial segments were reconstructed at 10 phases of the cardiac cycle for both pre- and postintervention based on the fusion of intravascular ultrasound (IVUS) and biplane angiographic images. An arbitrary Lagrangian-Eulerian formulation was used for the computational fluid dynamic analysis. The measured arterial translation was observed to be larger during systole after intervention and more out-of-plane motion was observed before intervention, indicating substantial alterations in the cardiac contraction after angioplasty. The time averaged axial wall shear stress ranged from -0.2 to 9.5 Pa before intervention compared to -0.02 to 3.53 Pa after intervention. Substantial oscillatory shear stress was present in the preintervention flow dynamics compared to that in the postintervention case.

Fluid Dynamic Analysis in a Human Left Anterior Descending Coronary Artery with Arterial Motion

A computational fluid dynamic (CFD) analysis is pre sented to describe local flow dynamics in both 3-D spatial and 4-D spatial and temporal domains from reconstructions of intravascular ultrasound (IVUS) and bi-plane angiographic fusion images. A left anterior descending (LAD) coronary artery segment geometry was accurately reconstructed and subsequently its motion was incorporated into the CFD model. The results indicate that the incorporation of motion had appreciable effects on blood flow patterns. The velocity profiles in the region of a stenosis and the circumferential distribution of the axial wall shear stress (WSS) patterns in the vessel are altered with the wall motion introduced in the simulation. The time-averaged axial WSS between simulations of steady flow and unsteady flow without arterial motion were comparable (-0.3 to 13.7 Pa in unsteady flow versus -0.2 to 10.1 Pa in steady flow) while the magnitudes decreased when motion was introduced (0.3-4.5 Pa). The arterial wall motion affects the time-mean WSS and the oscillatory shear index in the coronary vessel fluid dynamics and may provide more realistic predictions on the progression of atherosclerotic disease.

Validation of an accurate method for three-dimensional reconstruction and quantitative assessment of volumes, lengths and diameters of coronary vascular branches and segments from biplane angiographic projections

The goal of the study was the validation of an accurate method for three-dimensional reconstruction and quantitative assessment of volumes, lengths and diameters of coronary vascular branches and segments from biplane angiographic projections.

METHODS

The accuracy was tested in a complex phantom. In vivo, inter- and intraobserver agreement were assessed by analysis of routine angiograms. The sensitivity was evaluated using angiograms of patients having diagnostic vasoactive pharmacological intervention. Two-dimensional quantitative coronary angiography (2-D QCA) and 3-D QCA were compared concerning the accuracy of diameter evaluation.

RESULTS

3-D QCA yields accurate results (< 3% error) even based on nonorthogonal views, provided that projections parallel to the object are avoided. The inter- and intraobserver variability is < or = 5%. Significant (p < 0.01) changes of the volume (36-39%) and the diameter (19-21%) are detected following pharmacological intervention. 2-D QCA and 3-D QCA agree in short matched segments without foreshortening. 2-D QCA is rather sensitive to foreshortening and not suitable for evaluation of diameters of longer branches or total coronaries.

CONCLUSION

3-D QCA permits an accurate, reproducible and sensitive comprehensive three-dimensional geometric analysis of the coronaries and is superior to 2-D QCA with respect to extended diameter evaluation.

Biplane X-ray angiograms, intravascular ultrasound, and 3D visualization of coronary vessels

The technology for determination of the 3D vascular tree and quantitative characterization of the vessel lumen and vessel wall has become available. With this technology, cardiologists will no longer rely primarily on visual inspection of coronary angiograms but use sophisticated modeling techniques combining images from various modalities for the evaluation of coronary artery disease and the effects of treatment. Techniques have been developed which allow the calculation of the imaging geometry and the 3D position of the vessel centerlines of the vascular tree from biplane views without a calibration object, i.e., from the images themselves, removing the awkwardness of moving the patient to obtain 3D information. With the geometry and positional information, techniques for reconstructing the vessel lumen can now be applied that provide more accurate estimates of the area and shape of the vessel lumen. In conjunction with these developments, techniques have been developed for combining information from intravascular ultrasound images with the information obtained from angiography. The combination of these technologies will yield a more comprehensive characterization and understanding of coronary artery disease and should lead to improved and perhaps less invasive patient care.

Fusion of angiography and intravascular ultrasound in vivo: establishing the absolute 3-D frame orientation

Data fusion of biplane angiography and intravascular ultrasound (IVUS) facilitates geometrically correct reconstruction of coronary vessels. The locations of IVUS frames along the catheter pullback trajectory can be identified, however the IVUS image orientations remain ambiguous. An automated approach to determination of correct IVUS image orientation in three-dimensional space is reported. Analytical calculation of the catheter twist is followed by statistical optimization determining the absolute IVUS image orientation. The fusion method was applied to data acquired in patients undergoing routine coronary intervention, demonstrating the feasibility and good performance of our approach.

Validation of an accurate method for three-dimensional reconstruction and quantitative assessment of volumes, lengths and diameters of coronary vascular branches and segments from biplane angiographic projections

The goal of the study was the validation of an accurate method for three-dimensional reconstruction and quantitative assessment of volumes, lengths and diameters of coronary vascular branches and segments from biplane angiographic projections.

METHODS

The accuracy was tested in a complex phantom. In vivo, inter- and intraobserver agreement were assessed by analysis of routine angiograms. The sensitivity was evaluated using angiograms of patients having diagnostic vasoactive pharmacological intervention. Two-dimensional quantitative coronary angiography (2-D QCA) and 3-D QCA were compared concerning the accuracy of diameter evaluation.

RESULTS

3-D QCA yields accurate results (< 3% error) even based on nonorthogonal views, provided that projections parallel to the object are avoided. The inter- and intraobserver variability is < or = 5%. Significant (p < 0.01) changes of the volume (36-39%) and the diameter (19-21%) are detected following pharmacological intervention. 2-D QCA and 3-D QCA agree in short matched segments without foreshortening. 2-D QCA is rather sensitive to foreshortening and not suitable for evaluation of diameters of longer branches or total coronaries.

CONCLUSION

3-D QCA permits an accurate, reproducible and sensitive comprehensive three-dimensional geometric analysis of the coronaries and is superior to 2-D QCA with respect to extended diameter evaluation.

Geometrically correct 3-D reconstruction of intravascular ultrasound images by fusion with biplane angiography--methods and validation

In the rapidly evolving field of intravascular ultrasound (IVUS), the assessment of vessel morphology still lacks a geometrically correct three-dimensional (3-D) reconstruction. The IVUS frames are usually stacked up to form a straight vessel, neglecting curvature and the axial twisting of the catheter during the pullback. Our method combines the information about vessel cross-sections obtained from IVUS with the information about the vessel geometry derived from biplane angiography. First, the catheter path is reconstructed from its biplane projections, resulting in a spatial model. The locations of the IVUS frames are determined and their orientations relative to each other are calculated using a discrete approximation of the Frenet-Serret formulas known from differential geometry. The absolute orientation of the frame set is established, utilizing the imaging catheter itself as an artificial landmark. The IVUS images are segmented, using our previously developed algorithm. The fusion approach has been extensively validated in computer simulations, phantoms, and cadaveric pig hearts.

Assessment of diffuse coronary artery disease by quantitative analysis of coronary morphology based upon 3-D reconstruction from biplane angiograms

Quantitative evaluations on coronary vessel systems are of increasing importance in cardiovascular diagnosis, therapy planning, and surgical verification. Whereas local evaluations, such as stenosis analysis, are already available with sufficient accuracy, global evaluations of vessel segments or vessel subsystems are not yet common. Especially for the diagnosis of diffuse coronary artery diseases, the authors combined a 3D reconstruction system operating on biplane angiograms with a length/volume calculation. The 3D reconstruction results in a 3D model of the coronary vessel system, consisting of the vessel skeleton and a discrete number of contours. To obtain an utmost accurate model, the authors focussed on exact geometry determination. Several algorithms for calculating missing geometric parameters and correcting remaining geometry errors were implemented and verified. The length/volume evaluation can be performed either on single vessel segments, on a set of segments, or on subtrees. A volume model based on generalized elliptical conic sections is created for the selected segments. Volumes and lengths (measured along the vessel course) of those elements are summed up. In this way, the morphological parameters of a vessel subsystem can be set in relation to the parameters of the proximal segment supplying it. These relations allow objective assessments of diffuse coronary artery diseases.

Pressure-controlled reperfusion improves postischemic recovery of LV-hypertrophied rat hearts

The influence of pressure-controlled postischemic reperfusion (Rp) on functional and metabolic parameters in hearts of sham-operated rats and hypertrophied hearts of rats with aortic constriction were studied. Hypertrophied hearts are considered to be more susceptible to ischemia. The hearts were perfused in the Langendorff-technique for thirty minutes at 35 degrees C with Krebs-Henseleit bicarbonate buffer at a perfusion pressure (PP) of 75 mmHg and for five minutes at 15 degrees C with St. Thomas' Hospital cardioplegic solution at a PP of 60 mmHg. After a period of global ischemia of forty minutes' duration at 15 degrees C, reperfusion was started either abruptly (aRp: PP 75 mmHg immediately) or gently (gRp: PP 75 mmHg within thirty minutes); it lasted for forty-five minutes. Intraventricular peak systolic pressure (ISP) was monitored and energy-rich compounds (ATP, ADP, AMP, CrP, free Cr) were analyzed. In normal hearts, metabolic recovery was not affected by the mode of reperfusion, but functional recovery (ISP) averaged 88% of the preischemic control value after gRp as compared with 73% after aRp. In hypertrophied hearts, gentle reperfusion ameliorated both metabolic and functional recovery. At forty-five minute recovery, CrP averaged 5.1 mumol/g ww after aRp and 6.6 mumol/g ww after gRp (p less than 0.01), and ISP amounted to 73% of the preischemic control after aRp and to 85% after gRp.