Clostridioides difficile infection across the lifespan: Estimation using life tables

Using a life tables approach with 2011-2017 claims data, we calculated lifetime risks of Clostridioides difficile infection (CDI) beginning at age 18 years. The lifetime CDI risk rates were 32% in female patients insured by Medicaid, 10% in commercially insured male patients, and almost 40% in females with end-stage renal disease.

Increased Incidence and Risk of Septicemia and Urinary Tract Infection After Clostridioides difficile Infection

Background

Although increased occurrence of septicemia in persons with Clostridioides difficile infection (CDI) has been reported, incidence rates and risk of septicemia and urinary tract infection (UTI) after CDI are unclear.

Methods

The first episode of CDI was identified using 2011-2017 MarketScan and CMS Medicare data and CDI cases categorized by standard surveillance definitions. Uninfected persons were frequency matched 4:1 to cases by the CDI case surveillance definition. Multivariable Cox proportional hazards models were used to identify risk factors for septicemia and UTI within 90 days of CDI onset, accounting for the competing risk of death in the Medicare population.

Results

The incidence of septicemia was highest after hospital-onset CDI in the Medicare, younger commercial, and younger Medicaid populations (25.5%, 15.7%, and 19.5%, respectively) and lowest in those with community-associated CDI (3.8%, 4.3%, and 8.3%, respectively). In contrast, the incidence of UTI was highest in those with other healthcare facility onset CDI in all 3 populations (32.1%, 24.2%, and 18.1%, respectively). Hospital-onset CDI was associated with highest risk of septicemia compared with uninfected controls in all 3 populations. In the younger populations, risk of septicemia was more uniform across the CDI surveillance definitions. The risk of UTI was significantly higher in all CDI surveillance categories compared to uninfected controls, and among CDI cases it was lowest in those with community-associated CDI.

Conclusions

The incidence of septicemia is high after CDI, particularly after hospital-onset infection. Additional preventive measures are needed to reduce infectious complications of CDI.

Trends in the incidence of Clostridioides difficile infection in adults and the elderly insured by Medicaid compared to commercial insurance or Medicare only

OBJECTIVE

Few data are available to quantify the Clostridioides difficile infection (CDI) burden in US adults depending on Medicaid insurance status; thus, we sought to contribute to this body of information.

METHODS

Retrospective cohort study to identify adults with codes for CDI from 2011 to 2017 in MarketScan commercial and Medicaid databases (for those aged 25-64 years) and the CMS Medicare database (for those aged ≥65 years). CDI was categorized as healthcare-facility-associated (HCA-CDI) and community-associated CDI (CA-CDI). CDI incidence rates were compared by year, insurer, and age group.

RESULTS

The overall CDI incidence in the elderly was 3.1-fold higher in persons insured by Medicare plus Medicaid than in those insured by Medicare only (1,935 vs 618 per 100,000 person years (PY)), and the CDI incidence was 2.7-fold higher in younger adults with Medicaid compared to commercial insurance (195 vs 73 per 100,000 PY). From 2011 to 2017, HCA-CDI rates declined in the younger Medicaid population (124.0 to 95.2 per 100,000 PY; P < .001) but were stable in those commercially insured (25.9 to 24.8 per 100,000 PY; P = .33). In the elderly HCA-CDI rates declined from 2011 to 2017 in the Medicare-only population (403 to 318 per 100,000 PY; P < .001) and the Medicare plus Medicaid population (1,770 to 1,163 per 100,000 PY; P < .002). Persons with chronic medical conditions and those with immunocompromising conditions insured by Medicaid had 2.8- and 2.7-fold higher CDI incidence compared to the commercially insured population, respectively. The incidence of CDI was lowest in Medicaid and commercially insured younger adults without chronic medical or immunosuppressive conditions (67.5 and 45.6 per 100,000 PY, respectively).

CONCLUSIONS

Although HCA-CDI incidence decreased from 2011 to 2017 in elderly and younger adults insured by Medicaid, the burden of CDI remains much higher in low-income adults insured by Medicaid.

Healthcare Costs of Clostridioides difficile Infection in Commercially Insured Younger Adults

In a US adult population aged <65 years, attributable costs due to Clostridioides difficile infection (CDI) were highest in persons with hospital onset and lowest in those with community-associated CDI treated outside a hospital. The economic burden of CDI in younger adults underscores the need for additional CDI-preventive strategies.

Epidemiology of Intensive Care Admissions for Children in the US From 2001 to 2019

Importance

Estimates of the number of US children receiving intensive care unit (ICU) care and ICU admission patterns over time are lacking.

Objective

To determine how ICU admission patterns, use of critical care services, and the characteristics and outcomes of critically ill children have changed from 2001 to 2019.

Design, Setting, and Participants

This population-based retrospective cohort study used data from the Healthcare Cost and Utilization Project's state inpatient databases from a total of 21 US states in 2001, 2004, 2010, 2016, and 2019. Hospitalized children aged 0 to 17 years, excluding newborns (during birth hospitalization), were included. Patients admitted to rehabilitation institutions or psychiatric hospitals were also excluded. Data were analyzed from July 2021 to December 2022.

Exposures

Care in a nonneonatal ICU.

Main Outcomes and Measures

From extracted patient data, International Classification of Diseases, Ninth Revision, Clinical Modification, and Tenth Revision, Clinical Modification, codes were used to identify diagnoses, comorbid conditions, organ failures, and mechanical ventilation. Generalized linear Poisson regression and the Cuzick test were used to evaluate trends. US Census data were used to generate age- and sex-adjusted national estimates of ICU admissions and costs.

Results

Of 2 157 991 pediatric admissions, 275 656 (12.8%) included ICU care. The mean (SD) age was 6.43 (6.10) years; 121 894 individuals were female (44.2%), and 153 731 were male (55.8%). From 2001 to 2019, the prevalence of ICU care among hospitalized children increased from 10.6% to 15.5%. The percentage of ICU admissions in children's hospitals rose from 51.2% to 85.1% (relative risk [RR], 1.66; 95% CI, 1.64-1.68). The percentage of children admitted to an ICU with an underlying comorbidity increased from 46.2% to 57.0% (RR, 1.23; 95% CI, 1.22-1.25), and the percentage with preadmission technology dependence increased from 16.4% to 23.5% (RR, 1.44; 95% CI, 1.40-1.48). The prevalence of multiple organ dysfunction syndrome increased from 6.8% to 21.0% (RR, 3.12; 95% CI, 2.98-3.26), while mortality decreased from 2.5% to 1.8% (RR, 0.72; 95% CI, 0.66-0.79). Hospital length of stay increased by 0.96 days (95% CI, 0.73-1.18) for ICU admissions from 2001 to 2019. After inflation adjustment, total costs for a pediatric admission involving ICU care nearly doubled between 2001 and 2019. Nationally, an estimated 239 000 children were admitted to a US ICU in 2019, corresponding to $11.6 billion in hospital costs.

Conclusions and Relevance

In this study, the prevalence of children receiving ICU care in the US increased, as did length of stay, technology use, and associated costs. The US health care system must be equipped to care for these children in the future.

Catastrophic Health Care Expenditure Following Brachial Plexus Injury

PURPOSE

Brachial plexus injuries (BPIs) are devastating to patients not only functionally but also financially. Like patients experiencing other traumatic injuries and unexpected medical events, patients with BPIs are at risk of catastrophic health expenditure (CHE) in which out-of-pocket health spending exceeds 40% of postsubsistence income (income remaining after food and housing expenses). The individual financial strain after BPIs has not been previously quantified. The purpose of this study was to assess the proportion of patients with BPIs who experience risk of CHE after reconstructive surgery.

METHODS

Administrative databases were used from 8 states to identify patients who underwent surgery for BPIs. Demographics including age, sex, race, and insurance payer type were obtained. Inpatient billing records were used to determine the total surgical and inpatient facility costs within 90 days after the initial surgery. Due to data constraints, further analysis was only conducted for privately-insured patients. The proportion of patients with BPIs at risk of CHE was recorded. Predictors of CHE risk were determined from a multivariable regression analysis.

RESULTS

Among 681 privately-insured patients undergoing surgery for BPIs, nearly one-third (216 [32%]) were at risk of CHE. Black race and patients aged between 25 and 39 years were significant risk factors associated with CHE. Sex and the number of comorbidities were not associated with risk of CHE.

CONCLUSIONS

Nearly one-third of privately-insured patients met the threshold for being at risk of CHE after BPI surgery.

CLINICAL RELEVANCE

Identifying those patients at risk of CHE can inform strategies to minimize long-term financial distress after BPIs, including detailed counseling regarding anticipated health care expenditures and efforts to optimize access to appropriate insurance policies for patients with BPIs.

Association of Adverse Events with Antibiotic Treatment for Urinary Tract Infection

BACKGROUND

Little is known about the relative harms of different antibiotic regimens prescribed to treat uncomplicated urinary tract infection (UTI). We sought to compare the risk of adverse events associated with commonly-used oral antibiotic regimens for the outpatient treatment of uncomplicated UTI.

METHODS

We identified 1,169,033 otherwise healthy, non-pregnant women aged 18-44 years with uncomplicated UTI who initiated an oral antibiotic with activity against common uropathogens from July 1, 2006 to September 30, 2015. We used propensity score-weighted Kaplan-Meier methods and Cox proportional hazards regression models to estimate the association between antibiotic agent and adverse events.

RESULTS

Of two first-line agents, TMP/SMX (versus nitrofurantoin) was associated with higher risk of several adverse drug events including hypersensitivity reaction (hazard ratio [HR] 2.62, 95% CI 2.30-2.98), acute renal failure (HR 2.56, 95% CI 1.55-4.25), skin rash (HR 2.42, 95% CI 2.13-2.75), urticaria (HR 1.37, 95% CI 1.19-1.57), abdominal pain (HR 1.14, 95% CI 1.09-1.19), and nausea / vomiting (HR 1.18, 95% CI 1.10-1.28), but similar risk of potential microbiome-related adverse events. Compared to nitrofurantoin, non-first-line agents were associated with higher risk of several adverse drug events and potential microbiome-related adverse events including non-C. difficile diarrhea, C. difficile infection, vaginitis / vulvovaginal candidiasis, and pneumonia. Treatment duration modified the risk of potential microbiome-related adverse events.

CONCLUSIONS

The risks of adverse drug events and potential microbiome-related events differ widely by antibiotic agent and duration. These findings underscore the utility of using real-world data to fill evidentiary gaps related to antibiotic safety.

Care Fragmentation and Mortality in Readmission after Surgery for Hepatopancreatobiliary and Gastric Cancer: A Patient-Level and Hospital-Level Analysis of the Healthcare Cost and Utilization Project Administrative Database

BACKGROUND

Hepatopancreatobiliary (HPB) and gastric oncologic operations are frequently performed at referral centers. Postoperatively, many patients experience care fragmentation, including readmission to "outside hospitals" (OSH), which is associated with increased mortality. Little is known about patient-level and hospital-level variables associated with this mortality difference.

STUDY DESIGN

Patients undergoing HPB or gastric oncologic surgery were identified from select states within the Healthcare Cost and Utilization Project database (2006-2014). Follow-up was 90 days after discharge. Analyses used Kruskal-Wallis test, Youden index, and multilevel modeling at the hospital level.

RESULTS

There were 7,536 patients readmitted within 90 days of HPB or gastric oncologic surgery to 636 hospitals; 28% of readmissions (n = 2,123) were to an OSH, where 90-day readmission mortality was significantly higher: 8.0% vs 5.4% (p < 0.01). Patients readmitted to an OSH lived farther from the index surgical hospital (median 24 miles vs 10 miles; p < 0.01) and were readmitted later (median 25 days after discharge vs 12; p < 0.01). These variables were not associated with readmission mortality. Surgical complications managed at an OSH were associated with greater readmission mortality: 8.4% vs 5.7% (p < 0.01). Hospitals with <100 annual HPB and gastric operations for benign or malignant indications had higher readmission mortality (6.4% vs 4.7%, p = 0.01), although this was not significant after risk-adjustment (p = 0.226).

CONCLUSIONS

For readmissions after HPB and gastric oncologic surgery, travel distance and timing are major determinants of care fragmentation. However, these variables are not associated with mortality, nor is annual hospital surgical volume after risk-adjustment. This information could be used to determine safe sites of care for readmissions after HPB and gastric surgery. Further analysis is needed to explore the relationship between complications, the site of care, and readmission mortality.

Risk of antibiotic treatment failure in premenopausal women with uncomplicated urinary tract infection

PURPOSE

Acute uncomplicated urinary tract infections (UTIs) are among the most common indications for antibiotic prescriptions in otherwise healthy women. We compared the risk of treatment failure of antibiotic regimens for outpatient treatment of UTI in real-world practice.

METHODS

We identified non-pregnant, premenopausal women diagnosed with uncomplicated, lower tract UTI and prescribed an oral antibiotic with activity against common uropathogens. We used propensity score-weighted Kaplan-Meier functions to estimate 30-day risks and risk differences (RD) for pyelonephritis and UTI-related antibiotic prescription switch.

RESULTS

Of 1 140 602 patients, the distribution of index prescriptions was 44% fluoroquinolones (non-first-line), 28% trimethoprim-sulfamethoxazole (TMP/SMX) (first-line), 24% nitrofurantoin (first-line), 3% narrow-spectrum β-lactams (non-first-line), 1% broad-spectrum β-lactams (non-first-line), and 1% amoxicillin/ampicillin (non-recommended). Compared to the risk of pyelonephritis for nitrofurantoin (0.3%), risks were higher for TMP/SMX (RD, 0.2%; 95% CI, 0.2%-0.2%) and broad-spectrum β-lactams (RD, 0.2%; 95% CI, 0.1%-0.4%). Compared to the risk of prescription switch for nitrofurantoin (12.7%), the risk was higher for TMP/SMX (RD 1.6%; 95% CI 1.3%-1.7%) but similar for broad-spectrum β-lactams (RD -0.7%; 95% CI -1.4%-0.1%) and narrow-spectrum β-lactams (RD -0.3%; 95% CI -0.8%-0.2%). Subgroup analyses suggest TMP/SMX treatment failure may be due in part to increasing uropathogen resistance over time.

CONCLUSIONS

The risk of treatment failure differed by antibiotic agent, with higher risk associated with TMP/SMX versus nitrofurantoin, and lower or similar risk associated with broad- versus narrow-spectrum β-lactams. Given serious safety warnings for fluoroquinolones, these results suggest that nitrofurantoin may be preferable as the first-line agent for outpatient treatment of uncomplicated UTI.

Factors Associated With Postpartum Diabetes Screening in Women With Gestational Diabetes and Medicaid During Pregnancy

INTRODUCTION

Women with gestational diabetes are 7 times more likely to develop type 2 diabetes and require lifelong diabetes screening. Loss of health coverage after pregnancy, as occurs in states that did not expand Medicaid, limits access to guideline-driven follow-up care and fosters health inequity. This study aims to understand the factors associated with the receipt of postpartum diabetes screening for women with gestational diabetes in a state without Medicaid expansion.

METHODS

Electronic health record and Medicaid claims data were linked to generate a retrospective cohort of 1,078 women with gestational diabetes receiving care in Federally Qualified Health Centers in Missouri from 2010 to 2015. In 2019-2020, data were analyzed to determine the factors associated with the receipt of recommended postpartum diabetes screening (fasting plasma glucose, 2-hour oral glucose tolerance test, or HbA1c in specified timeframes) using a Cox proportional hazards model through 18 months of follow-up.

RESULTS

Median age in this predominantly urban population was 28 (IQR=24-33) years. Self-reported racial or ethnic minorities comprised more than half of the population. Only 9.7% of women were screened at 12 weeks, and 20.8% were screened at 18 months. Prenatal certified diabetes education (adjusted hazard ratio=1.74, 95% CI=1.22, 2.49) and access to public transportation (adjusted hazard ratio=1.70, 95% CI=1.13, 2.54) were associated with increased screening in a model adjusted for race/ethnicity, the total number of prenatal visits, the use of diabetes medication during pregnancy, and a pregnancy-specific comorbidity index that incorporated age.

CONCLUSIONS

This study underscores the importance of access to public transportation, prenatal diabetes education, and continued healthcare coverage for women on Medicaid to support the receipt of guideline-recommended follow-up care and improve health equity.

The Risks of Stone Diagnosis and Stone Removal Procedure After Different Bariatric Surgeries

Introduction: Nephrolithiasis is common after malabsorptive bariatric surgery; however, the comparative risk of stone formation after different bariatric surgeries remains unclear. We seek to compare the risk of stone diagnosis and stone procedure after gastric banding (GB), sleeve gastrectomy (SG), short-limb Roux-en-Y (SLRY), long-limb Roux-en-Y (LLRY), and biliopancreatic diversion with duodenal switch (BPDDS). Patients and Methods: Using an administrative database, we retrospectively identified 116,304 patients in the United States, who received bariatric surgery between 2007 and 2014, did not have a known kidney stone diagnosis before surgery, and were enrolled in the database for at least 1 year before and after their bariatric surgery. We used diagnosis and procedural codes to identify comorbidities and events of interest. Our primary analysis was performed with extended Cox proportional hazards models using time to stone diagnosis and time to stone procedure as outcomes. Results: The adjusted hazard ratio of new stone diagnosis from 1 to 36 months, compared to GB, was 4.54 for BPDDS (95% confidence interval [CI] 3.66-5.62), 2.12 for LLRY (95% CI 1.74-2.58), 2.15 for SLRY (95% CI 2.02-2.29), and 1.35 for SG (95% CI 1.25-1.46). Similar results were observed for risk of stone diagnosis from 36 to 60 months, and for risk of stone removal procedure. Male sex was associated with an overall 1.63-fold increased risk of new stone diagnosis (95% CI 1.55-1.72). Conclusions: BPDDS was associated with a greater risk of stone diagnosis and stone procedures than SLRY and LLRY, which were associated with a greater risk than restrictive procedures. Nephrolithiasis is more common after more malabsorptive bariatric surgeries, with a much greater risk observed after BPDDS and for male patients.

241. Rural-urban differences in antibiotic prescribing for uncomplicated urinary tract infections

Background

Identification of inappropriate antibiotic prescribing patterns is critical for designing antimicrobial stewardship programs. We sought to examine whether the risk of receipt of an inappropriate outpatient antibiotic prescription varied by rural-urban status among women with an uncomplicated urinary tract infection (UTI).

Methods

Using the IBM MarketScan Commercial Database, we identified U.S. women 18–44 years diagnosed with a new uncomplicated UTI and prescribed an oral antibiotic with activity against common uropathogens from April 2011 through June 2015. We classified first-line agents (nitrofurantoin, trimethoprim-sulfamethoxazole, and fosfomycin) as appropriate, non-first-line agents (fluoroquinolones and β-lactams) as inappropriate, and antibiotic duration as appropriate when the days’ supply was consistent with Infectious Diseases Society of America 2011 guidelines. Rural-urban status was defined by residence in a metropolitan statistical area. We used modified Poisson regression to determine the association between rural-urban status and inappropriate antibiotic receipt, accounting for patient- and provider-level characteristics.

Results

Of 670,450 women with uncomplicated UTI, 46.7% of antibiotic prescriptions were written for inappropriate agents and 76.1% for inappropriate durations (Figures 1 and 2). Use of inappropriate agents or durations did not change appreciably over the study period (2011–2013 vs. 2014–2015). Of 507,737 prescriptions with inappropriate duration, 501,496 (98.8%) were written for a days’ supply longer than recommended. Compared to urban women, rural women had similar risk of receipt of an inappropriate agent (adjusted risk ratio 0.99, 95% CI, 0.98–1.00) but were more likely to receive a prescription for an inappropriate duration (adjusted risk ratio 1.10, 95% CI, 1.09–1.11).

Figure 1. Distribution of antibiotic agent by rural-urban status

Figure 2. Distribution of the antibiotic prescription days’ supply by antibiotic agent and rural-urban status

Conclusion

Regardless of rural-urban status, the majority of antibiotic prescriptions for uncomplicated UTI were written for inappropriate agents and durations. Rural women were more likely to receive prescriptions with inappropriately long durations. Antimicrobial stewardship interventions are needed to improve outpatient UTI antibiotic prescribing and reduce unnecessary exposure to antibiotics, particularly in rural settings.

Disclosures

Margaret A. Olsen, PhD, MPH, Merck (Grant/Research Support)Pfizer (Consultant, Grant/Research Support)

17. Comparative Safety of Antibiotic Therapy for Outpatient Treatment of Uncomplicated Urinary Tract Infections

Background

Urinary tract infection (UTI) is one of the most common indications for outpatient antibiotic prescriptions in otherwise healthy women, yet the comparative safety of antibiotics for empirical therapy is not well established. We compared the risk of adverse drug events by antibiotic treatment regimen among premenopausal women with uncomplicated UTI.

Methods

Using the IBM MarketScan Commercial Database (2006–2015), we identified healthy, non-pregnant women aged 18–44 who were diagnosed with UTI and prescribed a same-day antibiotic with activity against common uropathogens. Patients were followed for outcomes with varying follow-up periods: 3 days (anaphylaxis), 14 days (acute renal failure, skin rash, urticaria/hives, nausea/vomiting, abdominal pain), 30 days (vaginitis/vulvovaginal candidiasis, non-C. difficile diarrhea) and 90 days (C. difficile diarrhea, pneumonia, tendinopathy, retinal detachment). We estimated propensity score-weighted hazard ratios (HR) and 95% confidence intervals (CI) using Cox proportional hazards models.

Results

Of 1,140,602 eligible women, the distribution of antibiotic receipt was fluoroquinolones (44%), trimethoprim-sulfamethoxazole (TMP/SMX) (28%), nitrofurantoin (24%), narrow-spectrum β-Lactam / β-Lactamase inhibitor combinations (“β-Lactams”) (3%), broad-spectrum β-Lactams (1%) and amoxicillin/ampicillin (1%). Of two first-line agents, we observed higher risk of outcomes among TMP/SMX vs. nitrofurantoin initiators: acute renal failure (HR 2.46, 95% CI 1.46–4.14), skin rash (HR 2.43, 95% CI 2.13–2.77), urticaria (HR 1.35, 95% CI 1.18–1.56), nausea/vomiting (HR 1.19, 95% CI 1.10–1.29) and abdominal pain (HR 1.14, 95% CI 1.09–1.19). Compared to nitrofurantoin, non-first-line agents (fluoroquinolones, broad-, and/or narrow-spectrum β-Lactams) were associated with higher risk of acute renal failure, skin rash, nausea/vomiting, abdominal pain, vaginitis/vulvovaginal candidiasis, diarrhea (C. difficile & non-C. difficile), pneumonia and tendinopathy.

Conclusion

The risk of adverse drug events differs widely by antibiotic agent, with substantial differences in first-line agents. Understanding antibiotic safety is critical to prevent suboptimal antibiotic prescribing and reduce adverse events.

Disclosures

Margaret A. Olsen, PhD, MPH, Merck (Grant/Research Support)Pfizer (Consultant, Grant/Research Support)

Potential missed opportunities for diagnosis of cryptococcosis and the association with mortality: A cohort study

BACKGROUND

Cryptococcosis is one of the most common life-threatening opportunistic mycoses worldwide. Insidious presentation and slow onset of symptoms make it difficult to recognize, complicating the diagnostic process. Delays in diagnosis may lead to increased mortality. We aim to determine the frequency of missed opportunities for diagnosis of cryptococcosis and its effects on mortality.

METHODS

To estimate the proportion of individuals with a potentially missed diagnosis for cryptococcosis in hospitalized patients, we conducted a retrospective cohort study using the Healthcare Cost and Utilization Project State Inpatient Databases from 2005 to 2015 from eight states. All hospitalized adult patients diagnosed with cryptococcal infection or cryptococcal meningitis were included. Potentially missed diagnoses were defined as admissions coded for a procedure or diagnosis suggestive of cryptococcosis in the 90-days prior to the initial cryptococcosis admission. Generalized estimating equations models were used to evaluate the association between underlying comorbidities and potential missed diagnosis of cryptococcosis and 90-day all-cause in-hospital mortality.

FINDINGS

Of 5,354 patients with cryptococcosis, 2,445 (45·7%) were people living with HIV (PLWH). Among PLWH, 493/2,445 (20·2%) had a potentially missed diagnosis, of which 83/493 (16·8%) died while hospitalized compared with 265/1,952 (13·6%) of those without a potentially missed diagnosis (relative risk [RR] 1·04, 95% CI 0·99-1·09). Among HIV-negative patients, 977/2,909 (33·6%) had a potentially missed diagnosis, of which 236/977 (24·2%) died while hospitalized compared with 298/1,932 (15·4%) of those not missed (RR 1·12, 95% CI 1·07-1·16).

INTERPRETATION

Missed opportunities to diagnose cryptococcosis are common despite highly efficacious diagnostic tests and are associated with increased risk of 90-day mortality in HIV-negative patients. A high index of clinical suspicion is paramount to promptly diagnose, treat, and improve cryptococcosis-related mortality.

FUNDING

National Center for Advancing Translational Sciences, Washington University Institute of Clinical and Translational Sciences, and the Agency for Healthcare Research and Quality.

Postpartum diabetes screening among low income women with gestational diabetes in Missouri 2010-2015

Background

Gestational diabetes increases risk for type 2 diabetes seven-fold, creating a large public health burden in a young population. In the US, there are no large registries for tracking postpartum diabetes screening among women in under-resourced communities who face challenges with access to care after pregnancy. Existing data from Medicaid claims is limited as women often lose this coverage within months of delivery. In this study, we aim to leverage data from electronic health records and administrative claims to better assess postpartum diabetes screening rates among low income women.

Methods

A retrospective population of 1078 women with gestational diabetes who delivered between 1/1/2010 and 10/8/2015 was generated by linking electronic health record data from 21 Missouri Federally Qualified Health Centers (FQHCs) with Medicaid administrative claims. Screening rates for diabetes were calculated within 12 weeks and 1 year of delivery. Initial screening after the first postpartum year was also documented.

Results

Median age in the final population was 28 (IQR 24–33) years with over-representation of black non-Hispanic and urban women. In the final population, 9.7% of women had a recommended diabetes screening test within 12 weeks and 18.9% were screened within 1 year of delivery. An additional 125 women received recommended screening for the first time beyond 1 year postpartum. The percentage of women who had a postpartum visit (83.9%) and any glucose testing (40.6%) in the first year far exceeded the proportion of women with recommended screening tests.

Conclusions

Linking electronic health record and administrative claims data provides a more complete picture of healthcare follow-up among low income women after gestational diabetes. While screening rates are higher than reported with claims data alone, there are opportunities to improve adherence to screening guidelines in this population.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-6475-0) contains supplementary material, which is available to authorized users.

Simplified risk prediction indices do not accurately predict 30-day death or readmission after discharge following colorectal surgery

BACKGROUND

Risk-prediction indices are one category of the many tools implemented to guide efforts to decrease readmissions. However, using fied models to predict a complex process can prove challenging. In addition, no risk-prediction index has been developed for patients undergoing colorectal surgery. Therefore, we evaluated the performance of a widely utilized simplified index developed at the hospital level - LACE (length of stay, acute admission, Charlson comorbidity index score, and emergency department visits) and developed and evaluated a novel index in predicting readmissions in this patient population.

METHODS

Using a retrospective split-sample cohort, patients discharged after colorectal surgery were identified within the inpatient databases of the Healthcare Cost and Utilization Project for the states of New York, California, and Florida (2006-2014). The primary outcome was death or readmission within 30 days after discharge. Multivariable logistic regression models incorporated patient comorbidities, postoperative complications, and hospitalization details, and were evaluated using the C statistic.

RESULTS

A total of 440,742 patients met eligibility criteria. The rate of death or readmission within 30 days after discharge was 14.0% (n = 61,757). When applied to surgical patients, the LACE index demonstrated a poor model fit (C = 0.631). The model fit improved significantly-but remained poor (C = 0.654; P < .001)-with the addition of the following variables, which are known to be associated with readmission after colorectal surgery: age, indication for surgery, and creation of a new ostomy. A novel, simplified model also yielded a poor model fit (C = 0.660).

CONCLUSION

Postdischarge death or readmission after colorectal surgery is not accurately modeled using existing, modified, or novel simplified risk prediction models. Payers and providers must ensure that quality improvement efforts applying simplified models to complex processes, such as readmissions following colorectal surgery, may not be appropriate, and that models reflect the relevant patient population.

1501. Comparative Effectiveness of Antibiotic Therapy for the Outpatient Treatment of Urinary Tract Infections Among Otherwise Healthy, Premenopausal Women

Background

The comparative effectiveness of antibiotics for empiric therapy for urinary tract infection (UTI) is not well established. We sought to estimate the risk of treatment failure by guideline-recommended agent for treatment of UTI in otherwise healthy, premenopausal women.

Methods

Using US commercial insurance claims data (2006–2015), we conducted a retrospective cohort study of nonpregnant women 18–44 years who received an outpatient diagnosis of UTI with a prescription for an antibiotic with activity against common uropathogens. For each antibiotic agent, we estimated the daily cumulative risk and 95% confidence intervals (CIs) of treatment failure defined by a subsequent UTI-related antibiotic prescription since the index prescription. Propensity-score weighting accounted for patient-, geographic-, and provider-level characteristics.

Results

Among 1,100,661 eligible women, the majority received second-line fluoroquinolones (43%), first-line trimethoprim-sulfamethoxazole (28%), or first-line nitrofurantoin (24%). Seven-day and 30-day treatment failure occurred in 8.4% (n = 92,382) and 20.5% (n = 225,746) of women, respectively. Among initiators of first-line agents, the 7-day weighted cumulative incidence estimates of treatment failure were lower for nitrofurantoin (6.0%, 95% CI, 5.9%–6.1%) vs. trimethoprim-sulfamethoxazole (8.8%, 95% CI, 8.7%–9.0%). Among initiators of second-line agents, treatment failure did not differ between fluoroquinolones (5.0%, 95% CI, 4.9%–5.1%), narrow-spectrum β-lactams (5.1%, 95% CI, 4.9%–5.4%), or broad-spectrum β-lactams (5.3%, 95% CI, 4.9%–5.7%). Among initiators of nonguideline recommended β-lactams, treatment failure was 9.6% (95% CI, 9.0%–10.3%). Results were similar for 30-day treatment failure, with the exception of lower risk for fluoroquinolones compared with other second-line agents.

Conclusion

The risk of treatment failure differs widely by antibiotic agent, with substantial differences between two first-line agents. Understanding the effectiveness of antibiotic therapy is critical to guide clinical decision making, reduce suboptimal antibiotic prescribing, and prevent antibiotic resistance and other adverse events.

Disclosures

All authors: No reported disclosures.

Genotypic and phenotypic characterization of human immunodeficiency virus type 1 variants isolated from patients treated with the protease inhibitor nelfinavir

Nelfinavir mesylate (formerly AG1343) is a potent and selective inhibitor of human immunodeficiency virus (HIV) protease approved for the treatment of individuals infected with HIV. Nucleotide sequence analysis of protease genes from plasma HIV type 1 (HIV-1) RNA revealed a unique aspartic acid (D)-to-asparagine (N) substitution at residue 30 (D30N) in 25 of 55 patients treated with nelfinavir for a median of 13 weeks. Although the appearance of D30N was occasionally associated with concurrent or sequential emergence of other changes (e.g., at residues 35, 36, 46, 71, 77, and 88), genotypic changes associated with phenotypic resistance to other protease inhibitors were not observed (e.g., at residues 48, 50, 82, and 84) or were only rarely observed (e.g., at residue 90). In phenotypic assays, viral isolates with high-level resistance to nelfinavir remained susceptible to indinavir, saquinavir, ritonavir, and amprenavir (formerly VX-478/141W94). Similar results were observed in phenotypic assays utilizing HIV-1 NL4-3, which contained the D30N substitution alone or in combination with substitutions at other residues (e.g., residues 46, 71, and 88). These data indicate that the initial pathway of resistance to nelfinavir is unique and suggest that individuals failing short courses of nelfinavir-containing regimens may respond to regimens containing other protease inhibitors.

Effect of supplemental fish meal on the lactation and reproductive performance of dairy cows

The influence of high protein diets (21% CP, DM basis), containing varied percentages of RUP, on lactation performance and fertility was evaluated. Sixty-two Holstein cows (65% multiparous) were blocked by age and randomly assigned to a 2 x 2 x 2 factorial design from d 12 to 125 postpartum. Factor 1 was 0 or 3.5% fish meal diet, factor 2 was location (Calan door versus free stall), and factor 3 was parity (first versus second or later). The soybean meal diet consisted of alfalfa hay, corn silage, barley, and soybean meal. The fish meal diet contained 3.5% fish meal (ruminant grade menhaden) that replaced a portion of the soybean meal. Cows fed the fish meal diet (40% RUP) had DMI, BW, and body condition similar to those of cows offered the soybean meal diet (34% RUP). Cows receiving the fish meal supplement tended to have higher milk protein production throughout the trial, higher milk production during the first 6 wk, and significantly lower ruminal ammonia concentrations than cows receiving the soybean meal diet. Differences in reproductive performance were not significant except for a diet by housing location interaction for conception rates from first AI.

Stereoselective actions of thiadiazinones on canine cardiac myocytes and myofilaments

Thiadiazinones are cardiotonic agents that have potent, direct, and stereoselective actions on the myofilament response to Ca2+ in intact myocardium. Their mechanism of action is unknown. We studied the effects of racemic thiadiazinone, EMD 53998 (5-[1-(3,4-dimethoxybenzoyl)-1,2,3,4-tetrahydro-6-quinolyl]-6-meth yl-3,6- dihydro-2H-1,3,4-thiadiazin-2-one), and its enantiomers on Ca2+ signaling in myocytes, myofilaments, and myofilament proteins. Intact canine ventricular myocytes responded to the positive enantiomer, EMD 57033, with an increase in the extent of shortening during twitch contractions without increasing the peak amplitude of the Ca2+ transient. The negative enantiomer, EMD 57439, also increased the extent of shortening, but in this case there was a concentration-dependent increase in the peak amplitude of the Ca2+ transient. This is predicted from in vitro data showing that this enantiomer is a relatively potent inhibitor of phosphodiesterase activity. There was no effect of EMD 57439 on the relation between pCa and actomyosin Mg-ATPase activity of canine heart myofibrils. In contrast, EMD 57033 shifted the pCa-Mg-ATPase activity relation to the left. There was no effect of either enantiomer on Ca2+ binding to myofilament troponin C. Moreover EMD 57033, but not EMD 57439, stimulated actomyosin ATPase activity of myofilament preparations in which either troponin or troponin-tropomyosin had been extracted. EMD 57033 had no effect on Mg-ATPase activity of pure ventricular myosin. EMD 57033 also stimulated the velocity of actin filament sliding on myosin heads adhered to nitrocellulose-coated glass coverslips. We propose that the action of EMD 57033 is at the actin-myosin interface on a "receptor" that may be on actin or the crossbridge. Drug binding to this domain appears to reverse the inhibition of actin-myosin interactions by troponin-tropomyosin and also to promote transition of crossbridges from weak to strong force-generating states.

Explanation of cerebral white--gray contrast in computed tomography

The difference in Hounsfield number between white and gray brain tissue is calculated from published chemical compositions and density values. The result of 5.5 Hounsfield units at typical CT energies is in excellent agreement with experiments. The difference arises because gray matter contains 8% more oxygen and 8% less carbon, due to its higher water and lower lipid content, and this increases the photoelectric absorption. Efforts to obtain greater contrast by lowering the X-ray energy will be offset by the noise increase at low energies.

Optimum energy for performing CT iodinated constrast studies

A study has been made of CT contrast for iodine as a function of X-ray energy from 80 to 140 kV constant potential. The EMI CT 1010 scanner was used for phantom measurements of contrast signal, noise, artefact and dose. The results show that optimum detectability occurs at 80-100 kV, with the close efficiency being somewhat better at 80kV.

Evaluation of edge-induced streaking artifacts in CT scanners

A phantom is presented which permits the evaluation of streaking artifacts produced in CT reconstructions by abrupt edges. Its application is demonstrated by results obtained from nine CT scanners. It is observed that even in regions where streaking is not readily apparent, edge-induced artifacts can significantly increase the variance in the reconstruction.

Computed tomography profiles of periventricular hypodensity in hydrocephalus and leukoencephalopathy

Profiles of hypodense periventricular white matter, drawn from the interior of the frontal horns through the surrounding white matter to the peripheral gray matter, were analyzed in 65 patients. Abnormal curves were grouped into four patterns: linear, double-slope, plateau, and bimodal. The first two, found primarily in hydrocephalic patients, appear to be due to transependymal passage of cerebrospinal fluid (CSF). The linear pattern was found more frequently in acute cases and indicates breakdown of the ventricular wall as a barrier. The double-slope pattern probably indicates a persistent or restored barrier effect at the wall, with residual CSF infiltration of the parenchyma. Most of the other patients' curves showed either a plateau pattern or (especially in primary leukoencephalopathy) a bimodal ("bumpy") pattern which is believed to correspond to the nonuniform nature of the pathological process.