Using a data-driven approach to define post-COVID conditions in US electronic health record data

OBJECTIVE

To create a data-driven definition of post-COVID conditions (PCC) by directly measure changes in symptomatology before and after a first COVID episode.

MATERIALS AND METHODS

Retrospective cohort study using Optum® de-identified Electronic Health Record (EHR) dataset from the United States of persons of any age April 2020-September 2021. For each person with COVID (ICD-10-CM U07.1 "COVID-19" or positive test result), we selected up to 3 comparators. The final COVID symptom score was computed as the sum of new diagnoses weighted by each diagnosis' ratio of incidence in COVID group relative to comparator group. For the subset of COVID cases diagnosed in September 2021, we compared the incidence of PCC using our data-driven definition with ICD-10-CM code U09.9 "Post-COVID Conditions", first available in the US October 2021.

RESULTS

The final cohort contained 588,611 people with COVID, with mean age of 48 years and 38% male. Our definition identified 20% of persons developed PCC in follow-up. PCC incidence increased with age: (7.8% of persons aged 0-17, 17.3% aged 18-64, and 33.3% aged 65+) and did not change over time (20.0% among persons diagnosed with COVID in 2020 versus 20.3% in 2021). For cases diagnosed in September 2021, our definition identified 19.0% with PCC in follow-up as compared to 2.9% with U09.9 code in follow-up.

CONCLUSION

Symptom and U09.9 code-based definitions alone captured different populations. Maximal capture may consider a combined approach, particularly before the availability and routine utilization of specific ICD-10 codes and with the lack consensus-based definitions on the syndrome.

NAFLD and NASH are obesity-independent risk factors in COVID-19: Matched real-world results from the large PINC AI™ Healthcare Database

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are potential risk factors for severe pneumonia and other infections. Available data on the role of NAFLD/NASH in worsening outcomes for COVID-19 are controversial and might be confounded by comorbidities.

METHODS

We used the PINC AI™ Healthcare Data Special Release (PHD-SR) to identify patients with COVID-19 (ICD-10) at approximately 900 hospitals in the United States. We performed exact matching (age, gender, and ethnicity) for patients with or without NAFLD/NASH, adjusting for demographics (admission type, region) and comorbidities (e.g., obesity, diabetes) through inverse probability of treatment weighting and then analysed hospitalisation-related outcomes.

RESULTS

Among 513 623 patients with SARS-CoV-2 (COVID-19), we identified 14 667 with NAFLD/NASH who could be matched to 14 667 controls. Mean age was 57.6 (±14.9) years, 50.8% were females and 43.7% were non-Hispanic whites. After matching, baseline characteristics (e.g., age, ethnicity, and gender) and comorbidities (e.g., hypertension, obesity, diabetes, and cardiovascular disease) were well balanced (standard difference (SD) <.10), except for cirrhosis and malignancies. Patients with COVID-19 and NAFLD/NASH had higher FIB-4 scores, a significantly longer hospital length of stay (LOS) and intensive care LOS than controls (9.4 vs. 8.3 days, and 10.4 vs. 9.3, respectively), even after adjusting for cirrhosis and malignancies. Patients with COVID-19 and NAFLD/NASH also had significantly higher risk of needing invasive mandatory ventilation (IMV) (odds ratio 1.0727; 95% CI 1.0095-1.1400). Other outcomes were similar in both groups.

CONCLUSIONS

In this large real-world cohort of patients hospitalised for COVID-19 in the United States, NAFLD/NASH were obesity-independent risk factors for complicated disease courses.

Substantial health and economic burden of COVID-19 during the year after acute illness among US adults at high risk of severe COVID-19

BACKGROUND

Post-COVID conditions encompass a range of long-term symptoms after SARS-CoV-2 infection. The potential clinical and economic burden in the United States is unclear. We evaluated diagnoses, medications, healthcare use, and medical costs before and after acute COVID-19 illness in US patients at high risk of severe COVID-19.

METHODS

Eligible adults were diagnosed with COVID-19 from April 1 to May 31, 2020, had ≥ 1 condition placing them at risk of severe COVID-19, and were enrolled in Optum's de-identified Clinformatics® Data Mart Database for ≥ 12 months before and ≥ 13 months after COVID-19 diagnosis. Percentages of diagnoses, medications, resource use, and costs were calculated during baseline (12 months preceding diagnosis) and the post-acute phase (12 months after the 30-day acute phase of COVID-19). Data were stratified by age and COVID-19 severity.

RESULTS

The cohort included 19,558 patients (aged 18-64 y, n = 9381; aged ≥ 65 y, n = 10,177). Compared with baseline, patients during the post-acute phase had increased percentages of blood disorders (16.3%), nervous system disorders (11.1%), and mental and behavioral disorders (7.7%), along with increases in related prescriptions. Overall, there were substantial increases in inpatient and outpatient healthcare utilization, along with a 23.0% increase in medical costs. Changes were greatest among older patients and those admitted to the intensive care unit for acute COVID-19 but were also observed in younger patients and those who did not require COVID-19 hospitalization.

CONCLUSIONS

There is a significant clinical and economic burden of post-COVID conditions among US individuals at high risk for severe COVID-19.

Persons diagnosed with COVID-19 in England in the Clinical Practice Research Datalink (CPRD): a cohort description

OBJECTIVE

To create case definitions for confirmed COVID-19 diagnoses, COVID-19 vaccination status and three separate definitions of high risk of severe COVID-19, as well as to assess whether the implementation of these definitions in a cohort reflected the sociodemographic and clinical characteristics of COVID-19 epidemiology in England.

DESIGN

Retrospective cohort study.

SETTING

Electronic healthcare records from primary care (Clinical Practice Research Datalink, CPRD) linked to secondary care data (Hospital Episode Statistics) data covering 24% of the population in England.

PARTICIPANTS

2 271 072 persons aged 1 year and older diagnosed with COVID-19 in CPRD Aurum between 1 August 2020 and 31 January 2022.

MAIN OUTCOME MEASURES

Age, sex and regional distribution of COVID-19 cases and COVID-19 vaccine doses received prior to diagnosis were assessed separately for the cohorts of cases identified in primary care and those hospitalised for COVID-19 (primary diagnosis code of ICD-10 U07.1 'COVID-19'). Smoking status, body mass index and Charlson Comorbidity Index were compared for the two cohorts, as well as for three separate definitions of high risk of severe disease used in the UK (National Health Service Highest Risk, PANORAMIC trial eligibility, UK Health Security Agency Clinical Risk prioritisation for vaccination).

RESULTS

Compared with national estimates, CPRD case estimates under-represented older adults in both the primary care (age 65-84: 6% in CPRD vs 9% nationally) and hospitalised (31% vs 40%) cohorts, and over-represented people living in regions with the highest median wealth areas of England (20% primary care and 20% hospital admitted cases in South East vs 15% nationally). The majority of non-hospitalised cases and all hospitalised cases had not completed primary series vaccination. In primary care, persons meeting high-risk definitions were older, more often smokers, overweight or obese, and had higher Charlson Comorbidity Index score.

CONCLUSIONS

CPRD primary care data are a robust real-world data source and can be used for some COVID-19 research questions, however, limitations of the data availability should be carefully considered. Included in this publication are supplemental files for a total of over 28 000 codes to define each of three definitions of high risk of severe disease.

Economic burden of COVID-19 for employers and employees in the United States

OBJECTIVE

Describe the economic burden of COVID-19 on employers and employees in the United States (US).

METHODS

A targeted literature review was conducted to evaluate the impact of COVID-19 on US-based employers and employees in terms of healthcare resource utilization (HCRU), medical costs, and costs associated with work-loss. Searches were conducted in MEDLINE, Embase, and EconLit using a combination of disease terms, populations, and outcomes to identify articles published from January 2021 to November 4, 2022. As data from the employer perspective were lacking, additional literature related to influenza were included to contextualize the impact of COVID-19, as it shifts into an endemic state, within the existing respiratory illness landscape.

RESULTS

A total of 41 articles were included in the literature review. Employer and employee perspectives were not well represented in the literature, and very few articles overlapped on any given outcome. HCRU, costs, and work impairment vary by community transmission levels, industry type, population demographics, telework ability, mitigation implementation measures, and company policies. Work-loss among COVID-19 cases were higher among the unvaccinated and in the week following diagnosis and for some, these continued for 6 months. HCRU is increased in those with COVID-19 and COVID-19-related HCRU can also continue for 6 months.

CONCLUSIONS

COVID-19 continues to be a considerable burden to employers. The majority of COVID-19 cases impact working age adults. HCRU is mainly driven by outpatient visits, while direct costs are driven by hospitalization. Productivity loss is higher for unvaccinated individuals. An increased focus to support mitigation measures may minimize hospitalizations and work-loss. A data-driven approach to implementation of workplace policies, targeted communications, and access to timely and appropriate therapies for prevention and treatment may reduce health-related work-loss and associated cost burden.

Estimated Effectiveness of Coadministration of the BNT162b2 BA.4/5 COVID-19 Vaccine With Influenza Vaccine

Importance

No data comparing the estimated effectiveness of coadministering COVID-19 vaccines with seasonal influenza vaccine (SIV) in the community setting exist.

Objective

To examine the comparative effectiveness associated with coadministering the BNT162b2 BA.4/5 bivalent mRNA COVID-19 vaccine (BNT162b2-biv [Pfizer BioNTech]) and SIV vs giving each vaccine alone.

Design, Setting, and Participants

A retrospective comparative effectiveness study evaluated US adults aged 18 years or older enrolled in commercial health insurance or Medicare Advantage plans and vaccinated with BNT162b2-biv only, SIV only, or both on the same day between August 31, 2022, and January 30, 2023. Individuals with monovalent or another brand of mRNA bivalent COVID-19 vaccine were excluded.

Exposure

Same-day coadministration of BNT162b2-biv and SIV; receipt of BNT162b2-biv only (for COVID-19-related outcomes) or SIV only (for influenza-related outcomes) were the comparator groups. For adults aged 65 years or older, only enhanced SIVs were included.

Main Outcomes and Measures

COVID-19-related and influenza-related hospitalization, emergency department (ED) or urgent care (UC) encounters, and outpatient visits.

Results

Overall, 3 442 996 individuals (57.0% female; mean [SD] age, 65 [16.7] years) were included. A total of 627 735 individuals had BNT162b2-biv and SIV vaccine coadministered, 369 423 had BNT162b2-biv alone, and 2 445 838 had SIV alone. Among those aged 65 years or older (n = 2 210 493; mean [SD] age, 75 [6.7] years; 57.9% female), the coadministration group had a similar incidence of COVID-19-related hospitalization (adjusted hazard ratio [AHR], 1.04; 95% CI, 0.87-1.24) and slightly higher incidence of emergency department or urgent care encounters (AHR, 1.12; 95% CI, 1.02-1.23) and outpatient visits (AHR, 1.06; 95% CI, 1.01-1.11) compared with the BNT162b2-biv-only group. Among individuals aged 18 to 64 years (n = 1 232 503; mean [SD] age, 47 [13.1] years; 55.4% female), the incidence of COVID-19-related outcomes was slightly higher among those who received both vaccines vs BNT162b2-biv alone (AHR point estimate range, 1.14-1.57); however, fewer events overall in this age group resulted in wider CIs. Overall, compared with those who received SIV alone, the coadministration group had a slightly lower incidence of most influenza-related end points (AHR point estimates 0.83-0.93 for those aged ≥65 years vs 0.76-1.08 for those aged 18-64 years). Negative control outcomes suggested residual bias and calibration of COVID-19-related and influenza-related outcomes with negative controls moved all estimates closer to the null, with most CIs crossing 1.00.

Conclusions and Relevance

In this study, coadministration of BNT162b2-biv and SIV was associated with generally similar effectiveness in the community setting against COVID-19-related and SIV-related outcomes compared with giving each vaccine alone and may help improve uptake of both vaccines.

Clinical outcomes of COVID-19 and influenza in hospitalized children <5 years in the US

Introduction

We compared hospitalization outcomes of young children hospitalized with COVID-19 to those hospitalized with influenza in the United States.

Methods

Patients aged 0-<5 years hospitalized with an admission diagnosis of acute COVID-19 (April 2021-March 2022) or influenza (April 2019-March 2020) were selected from the PINC AI Healthcare Database Special Release. Hospitalization outcomes included length of stay (LOS), intensive care unit (ICU) admission, oxygen supplementation, and mechanical ventilation (MV). Inverse probability of treatment weighting was used to adjust for confounders in logistic regression analyses.

Results

Among children hospitalized with COVID-19 (n = 4,839; median age: 0 years), 21.3% had an ICU admission, 19.6% received oxygen supplementation, 7.9% received MV support, and 0.5% died. Among children hospitalized with influenza (n = 4,349; median age: 1 year), 17.4% were admitted to the ICU, 26.7% received oxygen supplementation, 7.6% received MV support, and 0.3% died. Compared to children hospitalized with influenza, those with COVID-19 were more likely to have an ICU admission (adjusted odds ratio [aOR]: 1.34; 95% confidence interval [CI]: 1.21-1.48). However, children with COVID-19 were less likely to receive oxygen supplementation (aOR: 0.71; 95% CI: 0.64-0.78), have a prolonged LOS (aOR: 0.81; 95% CI: 0.75-0.88), or a prolonged ICU stay (aOR: 0.56; 95% CI: 0.46-0.68). The likelihood of receiving MV was similar (aOR: 0.94; 95% CI: 0.81, 1.1).

Conclusions

Hospitalized children with either SARS-CoV-2 or influenza had severe complications including ICU admission and oxygen supplementation. Nearly 10% received MV support. Both SARS-CoV-2 and influenza have the potential to cause severe illness in young children.

Incidence and clinical outcomes of pneumonia in persons with down syndrome in the United States

BACKGROUND

Persons with Down syndrome (DS) experience an increased risk of pneumonia. We determined the incidence and outcomes of pneumonia and relationship to underlying comorbidities in persons with and without DS in the United States.

METHODS

This retrospective matched cohort study used de-identified administrative claims data from Optum. Persons with DS were matched 1:4 to persons without DS on age, sex, and race/ethnicity. Pneumonia episodes were analyzed for incidence, rate ratios and 95 % confidence intervals, clinical outcomes, and comorbidities.

RESULTS

During 1-year follow-up among 33796 persons with and 135184 without DS, the incidence of all-cause pneumonia (pneumonia) was substantially higher among people with DS than those without DS (12427 vs. 2531 episodes/100000 person-years; 4.7-5.7 fold increase). Persons with DS and pneumonia were more likely to be hospitalized (39.4 % vs. 13.9 %) or admitted to the ICU (16.8 % vs. 4.8 %). Mortality was higher 1 year after first pneumonia (5.7 % vs. 2.4 %; P < 0.0001). Results were similar for episodes of pneumococcal pneumonia. Specific comorbidities were associated with pneumonia, particularly heart disease in children and neurologic disease in adults, which only partially mediated the effect of DS on pneumonia.

CONCLUSIONS

Among persons with DS, incidence of pneumonia and associated hospitalizations were increased; mortality among those with pneumonia was comparable at 30 days, but higher at 1 year. DS should be considered an independent risk condition for pneumonia.

Resilience in adolescence during the COVID-19 crisis in Canada

BACKGROUND

The COVID-19 pandemic constitutes a social crisis that will have long-term health consequences for much of the global population, especially for adolescents. Adolescents are triply affected as they: 1) are experiencing its immediate, direct effects, 2) will carry forward health habits they develop now into adulthood, and 3) as future parents, will shape the early life health of the next generation. It is therefore imperative to assess how the pandemic is influencing adolescent wellbeing, identify sources of resilience, and outline strategies for attenuating its negative impacts.

METHODS

We report the results of longitudinal analyses of qualitative data from 28 focus group discussions (FGDs) with 39 Canadian adolescents and of cross-sectional analyses of survey data from 482 Canadian adolescents gathered between September 2020 and August 2021. FGD participants and survey respondents reported on their: socio-demographic characteristics; mental health and wellbeing before and during the pandemic; pre- and during-pandemic health behaviours; experiences living through a crisis; current perceptions of their school, work, social, media, and governmental environments; and ideas about pandemic coping and mutual aid. We plotted themes emerging from FGDs along a pandemic timeline, noting socio-demographic variations. Following assessment for internal reliability and dimension reduction, quantitative health/wellbeing indicators were analyzed as functions of composite socio-demographic, health-behavioural, and health-environmental indicators.

RESULTS

Our mixed methods analyses indicate that adolescents faced considerable mental and physical health challenges due to the pandemic, and were generally in poorer health than expected in non-crisis times. Nevertheless, some participants showed significantly better outcomes than others, specifically those who: got more exercise; slept better; were food secure; had clearer routines; spent more time in nature, deep in-person social relationships, and leisure; and spent less time on social media.

CONCLUSIONS

Support for youth during times of crisis is essential to future population health because adolescence is a period in the life course which shapes the health behaviours, socio-economic capacities, and neurophysiology of these future parents/carers and leaders. Efforts to promote resilience in adolescents should leverage the factors identified above: helping them find structure and senses of purpose through strong social connections, well-supported work and leisure environments, and opportunities to engage with nature.

Self-reported gastrointestinal disorders among veterans with gulf war illness with and without posttraumatic stress disorder

BACKGROUND

Gulf War Illness (GWI) is a chronic, multi-symptom disorder affecting 25%-32% of Gulf War veterans. Veterans with GWI disproportionately suffer from gastrointestinal (GI) disorders. Given the increasing evidence supporting a gut-brain axis, we explore the relationship between post-traumatic stress disorder (PTSD), GWI, and self-reported GI disorders among GW veterans.

METHODS

Veterans from the Gulf War Era Cohort and Biorepository responded to a mail-based survey (N = 1058). They were stratified by GWI (Centers for Disease Control definition) and PTSD status. This yielded three groups: GWI-, GWI+/PTSD-, and GWI+/PTSD+. Multivariable logistic regression adjusting for demographic and military characteristics examined associations between GWI/PTSD groups and GI disorders. Results were expressed as adjusted odds ratios (aOR) with 95% confidence intervals (95% CI).

KEY RESULTS

The most frequently reported GI disorders were irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD), and colon polyps (CP). The GWI+/PTSD+ group had a higher odds of these disorders than the GWI+/PTSD- group (aOR_IBS  = 3.12, 95% CI: 1.93-5.05; aOR_GERD  = 2.04, 95% CI: 1.44-2.90; aOR_CP  = 1.85, 95% CI: 1.23-2.80), which had a higher odds of these disorders than the GWI- group (aOR_IBS  = 4.38, 95% CI: 1.55-12.36; aOR_GERD  = 2.51 95% CI: 1.63-3.87; aOR_CP  = 2.57, 95% CI: 1.53-4.32).

CONCLUSIONS & INFERENCES

GW veterans with GWI and PTSD have significantly higher odds of specific self-reported GI disorders than the other groups. Given the known bidirectional influences of the gut and brain, these veterans may benefit from a holistic healthcare approach that considers biopsychosocial contributors to the assessment and management of disease.

Use of the Postacute Sequelae of COVID-19 Diagnosis Code in Routine Clinical Practice in the US

IMPORTANCE

A new International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) diagnosis code (U09.9 Post COVID-19 condition, unspecified) was introduced by the Centers for Disease Control and Prevention on October 1, 2021.

OBJECTIVE

To examine the use of the U09.9 code and describe concurrently diagnosed conditions to understand physician use of this code in clinical practice.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study of US patients with an ICD-10-CM code for post-COVID-19 condition used deidentified patient-level claims data aggregated by HealthVerity. Children and adolescents (aged 0-17 years) and adults (aged 18-64 and ≥65 years) with a post-COVID-19 condition code were identified between October 1, 2021, and January 31, 2022. To identify a prior COVID-19 diagnosis, 3 months of continuous enrollment (CE) before the post-COVID-19 diagnosis date was required.

MAIN OUTCOMES AND MEASURES

Presence of the ICD-10-CM U09.9 code.

RESULTS

There were 56 143 patients (7723 female patients [61.2%]; mean [SD] age, 47.6 [19.2] years) with a post-COVID-19 diagnosis code, with cases increasing in mid-December 2021 following the trajectory of the Omicron case wave by 3 to 4 weeks. The analysis cohort included 12 622 patients after the 3-month preindex CE criteria was applied. Among this cohort, the median (IQR) age was 49 (35-61) years; however, 1080 (8.6%) were pediatric patients. The U09.9 code was used most often in the outpatient setting, although 305 older adults (14.0%) were inpatients. Only 698 patients (5.5%) had at least 1 of the 5 codes listed as possible concurrent conditions in the coding guidance. Only 8879 patients (70.4%) had a documented acute COVID-19 diagnosis code (569 [52.7%] among children), and the median (IQR) time between acute COVID-19 and post-COVID-19 diagnosis codes was 56 (21-200) days. The most common concurrently coded conditions varied by age; children experienced COVID-19-like symptoms (eg, 207 [19.2%] had cough and 115 [10.6%] had breathing abnormalities), while 459 older adults aged 65 years or older (21.1%) experienced respiratory failure and 189 (8.7%) experienced viral pneumonia.

CONCLUSIONS AND RELEVANCE

This retrospective cohort study found patients with a post-COVID-19 ICD-10-CM diagnosis code following the acute phase of COVID-19 disease among patients of all ages in clinical practice in the US. The use of the U09.9 code encompassed a wide range of conditions. It will be important to monitor how the use of this code changes as the pandemic continues to evolve.

Coronavirus Disease 2019 Severity and Risk of Subsequent Cardiovascular Events

BACKGROUND

Little is known about the relationship between coronavirus disease 2019 (COVID-19) severity and subsequent risk of experiencing a cardiovascular event (CVE) after COVID-19 recovery. We evaluated this relationship in a large cohort of United States adults.

METHODS

Using a claims database, we performed a retrospective cohort study of adults diagnosed with COVID-19 between 1 April 2020 and 31 May 2021. We evaluated the association between COVID-19 severity and risk of CVE >30 days after COVID-19 diagnosis using inverse probability of treatment-weighted competing risks regression. Severity was based on level of care required for COVID-19 treatment: intensive care unit (ICU) admission, non-ICU hospitalization, or outpatient care only.

RESULTS

A total of 1 357 518 COVID-19 patients were included (2% ICU, 3% non-ICU hospitalization, and 95% outpatient only). Compared to outpatients, there was an increased risk of any CVE for patients requiring ICU admission (adjusted hazard ratio [aHR], 1.80 [95% confidence interval {CI}, 1.71-1.89]) or non-ICU hospitalization (aHR, 1.28 [95% CI, 1.24-1.33]). Risk of subsequent hospitalization for CVE was even higher (aHRs, 3.47 [95% CI, 3.20-3.76] for ICU and 1.96 [95% CI, 1.85-2.09] for non-ICU hospitalized vs outpatient only).

CONCLUSIONS

COVID-19 patients hospitalized or requiring critical care had a significantly higher risk of experiencing and being hospitalized for post-COVID-19 CVE than patients with milder COVID-19 who were managed solely in the outpatient setting, even after adjusting for differences between these groups. These findings underscore the continued importance of preventing severe acute respiratory syndrome coronavirus 2 infection from progressing to severe illness to reduce potential long-term cardiovascular complications.

Predicting NAFLD prevalence in the United States using National Health and Nutrition Examination Survey 2017-2018 transient elastography data and application of machine learning

This cohort analysis investigated the prevalence of nonalcoholic fatty liver disease (NAFLD) and NAFLD with fibrosis at different stages, associated clinical characteristics, and comorbidities in the general United States population and a subpopulation with type 2 diabetes mellitus (T2DM), using the National Health and Nutrition Examination Survey (NHANES) database (2017-2018). Machine learning was explored to predict NAFLD identified by transient elastography (FibroScan^® ). Adults ≥20 years of age with valid transient elastography measurements were included; those with high alcohol consumption, viral hepatitis, or human immunodeficiency virus were excluded. Controlled attenuation parameter ≥302 dB/m using Youden's index defined NAFLD; vibration-controlled transient elastography liver stiffness cutoffs were ≤8.2, ≤9.7, ≤13.6, and >13.6 kPa for F0-F1, F2, F3, and F4, respectively. Predictive modeling, using six different machine-learning approaches with demographic and clinical data from NHANES, was applied. Age-adjusted prevalence of NAFLD and of NAFLD with F0-F1 and F2-F4 fibrosis was 25.3%, 18.9%, and 4.4%, respectively, in the overall population and 54.6%, 32.6%, and 18.3% in those with T2DM. The highest prevalence was among Mexican American participants. Test performance for all six machine-learning models was similar (area under the receiver operating characteristic curve, 0.79-0.84). Machine learning using logistic regression identified male sex, hemoglobin A1c, age, and body mass index among significant predictors of NAFLD (P ≤ 0.01). Conclusion: Data show a high prevalence of NAFLD with significant fibrosis (≥F2) in the general United States population, with greater prevalence in participants with T2DM. Using readily available, standard demographic and clinical data, machine-learning models could identify subjects with NAFLD across large data sets.

Population attributable fractions of underlying medical conditions for COVID-19 diagnosis and COVID-19 hospitalizations, ventilations, and deaths among adults in the United States

Background

Several underlying medical conditions have been reported to be associated with an increased risk of coronavirus disease 2019 (COVID-19) and related hospitalization and death. Population attributable fractions (PAFs) describing the proportion of disease burden attributable to underlying medical conditions for COVID-19 diagnosis and outcomes have not been reported.

Methods

A retrospective population-based cohort study was conducted using Optum’s de-identified Clinformatics Data Mart database. Individuals were followed up from 20 January 2020 to 31 December 2020 for diagnosis and clinical progression, including hospitalization, intensive care unit admission, intubation and mechanical ventilation or extracorporeal membrane oxygenation, and death. Adjusted rate ratios and PAFs of underlying medical conditions for COVID-19 diagnosis and disease progression outcomes were estimated by age (18–49, 50–64, 65–74, or ≥75 years), sex, and race/ethnicity.

Results

Of 10 679 566 cohort members, 391 964 (3.7%) were diagnosed with COVID-19, of whom 87 526 (22.3%) were hospitalized. Of those hospitalized, 26 640 (30.4%) died. Overall, cardiovascular disease and diabetes had the highest PAFs for COVID-19 diagnosis and outcomes of increasing severity across age groups (up to 0.49 and 0.35, respectively). Among adults ≥75 years of age, neurologic disease had the second-highest PAFs (0.05‒0.27) after cardiovascular disease (0.26‒0.44). PAFs were generally higher in Black persons than in other race/ethnicity groups for the same conditions, particularly in the 2 younger age groups.

Conclusions

A substantial fraction of the COVID-19 disease burden in the United States is attributable to cardiovascular disease and diabetes, highlighting the continued importance of COVID-19 prevention ( eg, vaccination, mask wearing, social distancing) and disease management of patients with certain underlying medical conditions.

A Retrospective Claims-Based Study Evaluating Clinical and Economic Burden Among Patients With Moderate to Severe Osteoarthritis Pain in the United States

Background: There has been limited evaluation of medication adherence, healthcare resource utilization (HCRU), and healthcare costs over time in patients with osteoarthritis (OA), and stratification by pain severity level has not been reported. Assessing such longitudinal changes may be useful to patients and healthcare providers for tracking disease progression, informing treatment options, and employing strategies to optimize patient outcomes. Objectives: To characterize treatment patterns, HCRU, and costs over time in patients with moderate to severe (MTS) OA pain in the United States. Methods: We conducted a retrospective claims analysis, using IBM® MarketScan® databases, from 2013-2018. Eligible patients were aged ≥45 years with ≥12 months pre-index (baseline) and ≥24 months (follow-up) of continuous enrollment; index date was defined as a physician diagnosis of hip or knee OA. An algorithm was employed to identify MTS OA pain patients, who were propensity score matched with patients having non-MTS OA pain. Data were summarized using descriptive statistics and univariate analyses. Results: After propensity score matching, the overall OA pain cohorts consisted of 186 374 patients each: 61% were female, mean age was 63 years, and two-thirds (65.6%) were of working age (45-65 years). Sleep-related conditions, anxiety, and depression were significantly higher in the MTS OA pain cohort vs non-MTS (P<0.001). At baseline and 12- and 24-month follow-ups, receipt of prescription pain medications, HCRU, and direct medical costs were significantly higher in the MTS OA pain cohort (all P<0.01). Medication adherence was significantly higher in the MTS OA pain cohort for all medication classes except analgesics/antipyretics, which were significantly lower vs the non-MTS OA pain cohort (all P<0.0001). Conclusions: The burden of MTS OA pain is substantial, with patterns that show increasing medication use, HCRU, and costs vs non-MTS OA pain patients over time. Understanding the heterogeneity within the OA population may allow us to further appreciate the true burden of illness for patients in pain.

Clinical and Pregnancy Outcomes of Coronavirus Disease 2019 Among Hospitalized Pregnant Women in the United States

Background

Pregnant women with coronavirus disease 2019 (COVID-19) may be at greater risk of poor maternal and pregnancy outcomes. This retrospective analysis reports clinical and pregnancy outcomes among hospitalized pregnant women with COVID-19 in the United States.

Methods

The Premier Healthcare Database-Special Release was used to examine the impact of COVID-19 among pregnant women aged 15-44 years who were hospitalized and who delivered compared with pregnant women without COVID-19. Outcomes evaluated were COVID-19 clinical progression, including the use of supplemental oxygen therapy, intensive care unit admission, critical illness, receipt of invasive mechanical ventilation/extracorporeal membrane oxygenation, maternal death, and pregnancy outcomes, including preterm delivery and stillbirth.

Results

Overall, 473 902 hospitalized pregnant women were included, 8584 (1.8%) of whom had a COVID-19 diagnosis (mean age = 28.4 [standard deviation = 6.1] years; 40% Hispanic). The risk of poor clinical and pregnancy outcomes was greater among pregnant women with COVID-19 compared with pregnant women without a COVID-19 diagnosis in 2020; the risk of poor clinical and pregnancy outcomes increased with increasing age. Hispanic and Black non-Hispanic women were consistently observed to have the highest relative risk of experiencing poor clinical or pregnancy outcomes across all age groups.

Conclusions

Overall, COVID-19 had a significant negative impact on maternal health and pregnancy outcomes. These data help inform clinical practice and counseling to pregnant women regarding the risks of COVID-19. Clinical studies evaluating the safety and efficacy of vaccines against severe acute respiratory syndrome coronavirus 2 in pregnant women are urgently needed.

Pandemic-related declines in hospitalization for non-COVID-19-related illness in the United States from January through July 2020

BACKGROUND

The COVID-19 pandemic, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has substantially impacted healthcare utilization worldwide. The objective of this retrospective analysis of a large hospital discharge database was to compare all-cause and cause-specific hospitalizations during the first six months of the pandemic in the United States with the same months in the previous four years.

METHODS

Data were collected from all hospitals in the Premier Healthcare Database (PHD) and PHD Special Release reporting hospitalizations from January through July for each year from 2016 through 2020. Hospitalization trends were analyzed stratified by age group, major diagnostic categories (MDCs), and geographic region.

RESULTS

The analysis included 286 hospitals from all 9 US Census divisions. The number of all-cause hospitalizations per month was relatively stable from 2016 through 2019 and then fell by 21% (57,281 fewer hospitalizations) between March and April 2020, particularly in hospitalizations for non-respiratory illnesses. From April onward there was a rise in the number of monthly hospitalizations per month. Hospitalizations per month, nationally and in each Census division, decreased for 20 of 25 MDCs between March and April 2020. There was also a decrease in hospitalizations per month for all age groups between March and April 2020 with the greatest decreases in hospitalizations observed for patients 50-64 and ≥65 years of age.

CONCLUSIONS

Rates of hospitalization declined substantially during the first months of the COVID-19 pandemic, suggesting delayed routine, elective, and emergency care in the United States. These lapses in care for illnesses not related to COVID-19 may lead to increases in morbidity and mortality for other conditions. Thus, in the current stage of the pandemic, clinicians and public-health officials should work, not only to prevent SARS-CoV-2 transmission, but also to ensure that care for non-COVID-19 conditions is not delayed.

COVID-19-associated hospitalizations among children less than 12 years of age in the United States

OBJECTIVES

To describe the characteristics, healthcare resource use and costs associated with initial hospitalization and readmissions among pediatric patients with COVID-19 in the US.

METHODS

Hospitalized pediatric patients, 0-11 years of age, with a primary or secondary discharge diagnosis code for COVID-19 (ICD-10 code U07.1) were selected from 1 April 2020 to 30 September 2021 in the US Premier Healthcare Database Special Release (PHD SR). Patient characteristics, hospital length of stay (LOS), in-hospital mortality, hospital costs, hospital charges, and COVID-19-associated readmission outcomes were evaluated and stratified by age groups (0-4, 5-11), four COVID-19 disease progression states based on intensive care unit (ICU) and invasive mechanical ventilation (IMV) usage, and three sequential calendar periods. Sensitivity analyses were performed using the US HealthVerity claims database and restricting the analyses to the primary discharge code.

RESULTS

Among 4,573 hospitalized pediatric patients aged 0-11 years, 68.0% were 0-4 years and 32.0% were 5-11 years, with a mean (median) age of 3.2 (1) years; 56.0% were male, and 67.2% were covered by Medicaid. Among the overall study population, 25.7% had immunocompromised condition(s), 23.1% were admitted to the ICU and 7.3% received IMV. The mean (median) hospital LOS was 4.3 (2) days, hospital costs and charges were $14,760 ($6,164) and $58,418 ($21,622), respectively; in-hospital mortality was 0.5%. LOS, costs, charges, and in-hospital mortality increased with ICU admission and/or IMV usage. In total, 2.1% had a COVID-19-associated readmission. Study outcomes appeared relatively more frequent and/or higher among those 5-11 than those 0-4. Results using the HealthVerity data source were generally consistent with main analyses.

LIMITATIONS

This retrospective administrative database analysis relied on coding accuracy and inpatient admissions with validated hospital costs.

CONCLUSIONS

These findings underscore that children aged 0-11 years can experience severe COVID-19 illness requiring hospitalization and substantial hospital resource use, further supporting recommendations for COVID-19 vaccination.

Hospitalization and mortality trends among patients with confirmed COVID-19 in the United States, April through August 2020

Background: The United States has experienced high COVID- 19 case counts, hospitalizations, and death rates. This retrospective analysis reports changing trends in the demographics and clinical outcomes of hospitalized US COVID-19 patients between April and August 2020.

Design and methods: The Premier Healthcare Database Special Release was used to examine patient demographics of hospitalized COVID-19 patients from all US Census Bureau divisions. Demographics included age, sex, race, and ethnicity. Clinical outcomes included in-hospital mortality, intensive care unit (ICU) admission, and receipt of invasive mechanical ventilation.

Results: Overall, 146,491 hospitalized COVID-19 patients were included (mean [SD] age, 61.0 [18.4] years; 51.7% male; 29.6% White non-Hispanic). Monthly total hospitalizations decreased from 44,854 in April to 18,533 in August; ICU admissions increased from 19.8% to 23.6%, and ventilator use and inpatient mortality decreased from 18.6% to 14.5% and 21.0% to 11.4%, respectively. Inpatient mortality was highest in the Middle Atlantic division (20.3%), followed by the New England (19.0%), East North Central (14.2%), and Mountain (13.7%) divisions. Black non-Hispanic patients were overrepresented among hospitalizations (19.0%); this group comprises 12.2% of the US population. Patients aged <65 years made up 53% of hospitalizations and had lower inpatient mortality than those aged ≥65 years.

Conclusions: Hospitalizations, ventilator use, and mortality decreased, while ICU admission rates increased from April to August 2020. Older individuals and Black non-Hispanics were found to be at elevated risk of severe outcomes. These trends could inform ongoing patient care and US public health policies to limit the further spread of SARS-CoV-2.

Moderate to Severe Osteoarthritis Pain and Its Impact on Patients in the United States: A National Survey

Purpose

Osteoarthritis (OA) is one of the most common causes of chronic pain and a leading cause of disability in the US. The objective of this study was to examine the clinical and economic burden of OA by pain severity.

Patients and Methods

We used nationally representative survey data. Adults ≥18 years with self-reported physician-diagnosed OA and experiencing OA pain were included in the study. OA pain severity was measured using the Short Form McGill Pain Questionnaire Visual Analog Scale (SF-MPQ-VAS). Data were collected for demographics, clinical characteristics, health-related quality of life (HRQoL), productivity, OA treatment, adherence to pain medication, and healthcare resource utilization. Univariate analysis was performed to examine differences between respondents with moderate-to-severe OA pain vs those with mild OA pain.

Results

Higher proportions of respondents with moderate-to-severe OA pain (n=3798) compared with mild OA pain (n=2038) were female (69.4% vs 57.3%), <65 years of age (54.8% vs 43.4%), and not employed (70.6% vs 64.5%). Respondents with moderate-to-severe OA pain experienced OA pain daily (80.8% vs 48.8%), were obese (53.0% vs 40.5%), had more comorbidities (sleep disturbance, insomnia, depression, and anxiety), and reported significantly poorer health status and HRQoL, and greater productivity and activity impairment (all P<0.05). Moderate-to-severe OA pain respondents were prescribed significantly more pain medications than mild OA pain respondents (41.0% vs 17.0%) and had higher adherence (75.9% vs 64.1%) yet were less satisfied with their pain medications (all P<0.001). Outpatient and emergency room visits, and hospitalizations in the 6 months prior to the survey were significantly higher in moderate-to-severe OA pain respondents vs those with mild OA pain (all P<0.05).

Conclusion

Patient and clinical burden was significantly greater in moderate-to-severe OA pain respondents vs mild OA pain respondents and may inform decision-making for appropriate resource allocation and effective management strategies that target specific subgroups.

Evaluation of COVID-19 vaccine breakthrough infections among immunocompromised patients fully vaccinated with BNT162b2

OBJECTIVE

To evaluate COVID-19 vaccine breakthrough infections among immunocompromised (IC) individuals.

METHODS

Individuals vaccinated with BNT162b2 were selected from the US HealthVerity database (10 December 2020 to 8  July 2021). COVID-19 vaccine breakthrough infections were examined in fully vaccinated (≥14 days after 2nd dose) IC individuals (IC cohort), 12 mutually exclusive IC condition groups, and a non-IC cohort. IC conditions were identified using an algorithm based on diagnosis codes and immunosuppressive (IS) medication usage.

RESULTS

Of 1,277,747 individuals ≥16 years of age who received 2 BNT162b2 doses, 225,796 (17.7%) were identified as IC (median age: 58 years; 56.3% female). The most prevalent IC conditions were solid malignancy (32.0%), kidney disease (19.5%), and rheumatologic/inflammatory conditions (16.7%). Among the fully vaccinated IC and non-IC cohorts, a total of 978 breakthrough infections were observed during the study period; 124 (12.7%) resulted in hospitalization and 2 (0.2%) were inpatient deaths. IC individuals accounted for 38.2% (N = 374) of all breakthrough infections, 59.7% (N = 74) of all hospitalizations, and 100% (N = 2) of inpatient deaths. The proportion with breakthrough infections was 3 times higher in the IC cohort compared to the non-IC cohort (N = 374 [0.18%] vs. N = 604 [0.06%]; unadjusted incidence rates were 0.89 and 0.34 per 100 person-years, respectively. Organ transplant recipients had the highest incidence rate; those with >1 IC condition, antimetabolite usage, primary immunodeficiencies, and hematologic malignancies also had higher incidence rates compared to the overall IC cohort. Incidence rates in older (≥65 years old) IC individuals were generally higher versus younger IC individuals (<65).

LIMITATIONS

This retrospective analysis relied on coding accuracy and had limited capture of COVID-19 vaccine receipt.

CONCLUSIONS

COVID-19 vaccine breakthrough infections are rare but are more common and severe in IC individuals. The findings from this large study support the FDA authorization and CDC recommendations to offer a 3rd vaccine dose to increase protection among IC individuals.

Health outcomes and economic burden of hospitalized COVID-19 patients in the United States

OBJECTIVE

The aims of this study were to evaluate health outcomes and the economic burden of hospitalized COVID-19 patients in the United States.

METHODS

Hospitalized patients with a primary or secondary discharge diagnosis code for COVID-19 (ICD-10 code U07.1) from 1 April to 31 October 2020 were identified in the Premier Healthcare COVID-19 Database. Patient demographics, hospitalization characteristics, and concomitant medical conditions were assessed. Hospital length of stay (LOS), in-hospital mortality, hospital charges, and hospital costs were evaluated overall and stratified by age groups, insurance types, and 4 COVID-19 disease progression states based on intensive care unit (ICU) and invasive mechanical ventilation (IMV) usage.

RESULTS

Of the 173,942 hospitalized COVID-19 patients, the median age was 63 years, 51.0% were male, and 48.5% were covered by Medicare. The most prevalent concomitant medical conditions were cardiovascular disease (73.5%), hypertension (64.8%), diabetes (40.7%), obesity (27.0%), and chronic kidney disease (24.2%). Approximately one-fifth (21.9%) of the hospitalized COVID-19 patients were admitted to the ICU and 16.9% received IMV; most patients (73.6%) did not require ICU admission or IMV, and 12.4% required both. The median hospital LOS was 5 days, in-hospital mortality was 13.6%, median hospital charges were $43,986, and median hospital costs were $12,046. Hospital LOS and in-hospital mortality increased with ICU and/or IMV usage and age; hospital charges and costs increased with ICU and/or IMV usage. Patients with both ICU and IMV usage had the longest median hospital LOS (15 days), highest in-hospital mortality (53.8%), and highest hospital charges ($198,394) and hospital costs ($54,402).

LIMITATIONS

This retrospective administrative database analysis relied on coding accuracy and a subset of admissions with validated/reconciled hospital costs.

CONCLUSIONS

This study summarizes the severe health outcomes and substantial hospital costs of hospitalized COVID-19 patients in the US. The findings support the urgent need for rapid implementation of effective interventions, including safe and efficacious vaccines.

Renal Clearances in Continuous Ambulatory Peritoneal Dialysis: Differences between Diabetic and Non-Diabetic Subjects

We analyzed the effect of diabetes on the decline of residual renal function during the course of CAPD in a cross-sectional study including 105 diabetic subjects (41 women) who had 207 clearance studies and 125 non-diabetic subjects (50 women, 265 clearance studies). CAPD duration was 11.5±10.5 months in the diabetic group (DG) and 16.8±18.6 months in the non-diabetic group (NDG, P < 0.001). The DG had lower urine volume than the NDG (0.52±0.46 vs 0.61±0.50 L/24-h, P < 0.05), while urine-to-plasma concentration ratio was higher in the DG for creatinine (13.5±9.4 vs 11.5±11.0, P <0.05) and did not differ for urea. Weekly renal Kt/V urea (DG 0.51±0.57, NDG 0.53±0.49) and Ccr (DG 31.0±28.7 NDG 29.3±26.5 L/1.73 m2) did not differ. The slopes of the regressions of CAPD duration on renal clearances did not differ. These regressions allowed estimates of the time, from the onset of CAPD, at which renal clearances become negligible. These estimates differed for both urea clearance (DG 35.3, NDG 50.5 months) and creatinine clearance (DG 43.2, NDG 57.6 months). The slope of the regression of renal urea clearance on renal creatinine clearance was steeper in the DG, suggesting a higher renal creatinine clearance in the DG than in the NDG when renal urea clearance is the same in the two groups. Subtle differences in the rate of decline of renal function can be detected between diabetic and non-diabetic subjects on CAPD by detailed statistical analysis. These findings are supportive of the studies which have identified diabetes mellitus as a predictor of loss of residual renal function during the course of CAPD. In addition, the relationship between the renal urea and creatinine clearances differs between diabetic and non-diabetic subjects on CAPD. Therefore, the dose of CAPD required for adequate total clearances may differ between diabetic and non-diabetic subjects.

Estimated versus Predicted Creatinine Generation as an Indicator of Compliance with the Prescribed Dose of Continuous Peritoneal Dialysis

The expression (Estimated - Predicted)/Predicted creatinine generation {(E-P)IP} has been proposed as an index of compliance in continuous peritoneal dialysis (CPD). We attempted to define an (E-P)IP value that can be used as a cut-off for non-compliance and to characterize the relation of (E-P)IP to serum albumin. In 324 clearance studies, (E-P)/P had a normal distribution with a mean of +0.094 and an SD of 0.357. In these studies, there was a weak correlation between (E-P)/P and serum albumin (r=0.12, P<0.05), but (E-P)/P was not a predictor of serum albumin by logistic regression. In 34 CPD patients, who had an increase in the dose of CPD resulting in an increase in measured creatinine clearance from 43.8 ± 14.0 to 66.1 ± 17.6 L/1.73 m2 weekly (P<0.001), (E-P)/P increased correspondingly from +0.018 ± 0.284 to +0.153 ± 0.369 (P = 0.018), although all subjects should be in a steady state of creatinine excretion in the second study. The rise in (E-P)/P was statistically significant in the subgroup of 17 subjects who had a decrease in serum albumin, but not in the subgroup of 14 subjects who had an increase in serum albumin from the first to the second clearance study. The (E-P)/P cut-off for a definitive diagnosis of CPD non-compliance may be around +0.400 or +0.500. The findings of this study suggest that non-compliance, as indicated by (E-P)/P, has an adverse effect on serum albumin and that non-compliance increases after a prescribed increase in the dose of CPD.

Effect of hematocrit on dialyzer urea and creatinine clearance indices in a hemodialysis patient with erythrocytosis

The association between azotemic index dialyzer clearances and hematocrit was investigated in a 63-year-old dialysis-dependent man with acquired renal cysts. During 43 months of hemodialysis, hematocrit rose from 27.3 to 65.0 vol%, as a consequence of high serum erythropoietin levels. Concomitantly, dry weight also increased from 116.8 to 140.8 kg. Both hematocrit and dry weight correlated with: (a) urea reduction ratio, (b) creatinine reduction ratio (CRR), and (c) KT/V urea. All correlations were negative. Stepwise regression showed that only hematocrit was an independent correlate of the CRR (CRR = 0.662 - 007∗ Hct, R2 = 0.770); whereas, both hematocrit (Hct) and weight (W) were independent correlates of KT/V urea (KT/V = 2.070 - 0.005∗Hct - 0.009∗W, R2 = 0.721). In addition to creatinine clearance, urea clearance through the dialyzer is reduced by a rising hematocrit. The effect of hematocrit on urea clearance is relatively small. Therefore, it requires large changes in hematocrit in order to be detected

Endodontic management of mandibular central incisor fused to a supernumerary tooth associated with a talon cusp: a case report

AIM

To report the successful non-surgical endodontic management of a mandibular central incisor fused to a supernumerary tooth associated with a talon cusp.

SUMMARY

Fusion and gemination are developmental anomalies of teeth that may require endodontic treatment. In this article, a case of successful endodontic management of a permanent mandibular right central incisor fused to its supernumerary counterpart associated with a talon cusp is reported. The incidence of fusion in mandibular anteriors is rare. A search of the literature failed to reveal any reports on the fusion of a permanent mandibular central incisor with its supernumerary counterpart associated with a talon cusp. Successful non-surgical endodontic management of a case is reported.

KEY LEARNING POINTS

•  Fused and geminated teeth requiring endodontic treatment present diagnostic and technical challenges. • An exact differentiation between fusion and gemination may not be critically important for treatment. • The use of an operating microscope for detection of additional root canal orifices in complicated cases is recommended.

Molecular insights into uremic cardiomyopathy: cardiotonic steroids and Na/K ATPase signaling

Patients with chronic renal failure develop a "uremic" cardiomyopathy characterized by diastolic dysfunction, left ventricular hypertrophy, fibrosis, and systemic oxidant stress. Patients with chronic renal failure also are known to have increases in the circulating concentrations of endogenous cardiotonic steroids (also referred to as endogenous digitalis-like substances.) Endogenous cardiotonic steroids produce reactive oxygen species as part of the signal cascade induced by binding to the plasmalemmal Na/K-ATPase in patients, and this signal cascade appears capable of inducing several key pathophysiologic features of uremic cardiomyopathy. In addition, these patients develop both fibrosis and oxidant stress without a known mechanism. In this review we highlight data supporting the hypothesis that endogenous cardiotonic steroids are a key molecular component involved in the diastolic dysfunction, left ventricular hypertrophy, fibrosis, and systemic oxidant stress associated with chronic kidney disease.

Hypokalemia potentiates ouabain's effect on calcium cycling and cardiac growth

We have previously noted that in neonatal myocytes grown in culture, reductions in extracellular K+ concentration produced a hypertrophic response as assessed by induction of early response genes, atrial natriuretic peptide and skeletal actin and repression of the alpha 3 isoform of the sodium pump in a dose dependent manner. Similarly, decreases in media K+ concentration caused increases in cytosolic calcium concentration in a dose dependent manner, which correlated with repression of alpha 3 expression. In the current study we demonstrate that decreases in media K+ concentration caused increases in cytosolic calcium concentration in isolated adult rat cardiac myocytes. These increases are potentiated by the addition of the cardiotonic steroid, ouabain and blocked by the addition of the Src kinase inhibitor Herbimycin A. In parallel studies performed in vivo, when rats subjected to dietary K+ restriction were subsequently subjected to partial (5/6th) nephrectomy for 4 weeks, cardiac growth was greater than in rats fed a control diet. These data suggest that hypokalemia may produce phenotypic alterations consistent with cardiac hypertrophy as well as potentiate the cardiovascular effects of cardiotonic steroids.

A polyherbal vaginal pessary with spermicidal and antimicrobial action: evaluation of its safety

A polyherbal vaginal pessary (Praneem) has been formulated that has antimicrobial properties against genital pathogens in addition to spermicidal action. Thus, it has dual potential as a barrier method for contraception and for providing protection against some sexually transmitted infections. The present study reports the findings of a multicentre trial that was conducted to evaluate the safety of this product. Trials were carried out in 23 women in three centres in India: the Postgraduate Institute of Medical Education and Research, Chandigarh; Safdarjang Hospital, New Delhi; and Kamla Nehru Memorial Hospital, Allahabad. Thorough clinical and pelvic examinations were carried out as well as cervical cytology, blood biochemistry and haematology before and after use of the polyherbal pessary intravaginally once daily for 7 consecutive days. No toxicity was observed on clinical examination or by laboratory investigations. Daily intravaginal use of this pessary for 7 days had no adverse effects on cervical cytology or on metabolic and organ functions.

Promoter and intron-1 region polymorphisms in the IFNG gene in patients with hepatitis E

Allelic and genotype variations in the promoter region and the dinucleotide (CA)(n) repeat region in intron 1 of the interferon-g (IFNG) gene were analysed by direct sequencing and simple sequence length polymorphism (SSLP), respectively, in patients with acute hepatitis, and the prevalence was compared with that in healthy controls. Our results showed a significant association of heterozygous genotypes (CA)12/(CA)14 and (CA)12/(CA)16 in intron 1 of the IFNG gene in all categories of patients with acute hepatitis, classified on the basis of presence or absence of hepatitis E virus (HEV), in comparison with healthy controls. A novel polymorphism, -288 A-->T [from the translational start site, as per Human Genome Organization (HUGO) nomenclature], in the promoter region of the IFNG gene leading to a loss of the consensus domain for the interferon-stimulated response element (ISRE), as predicted by in silico analysis, was observed in 12.5% of patients with acute HEV infection. However, no significant difference in allele or genotype frequency was observed for the -288 promoter polymorphism, although the heterozygous -288 A/T genotype showed a moderate risk in patients with acute HEV infection alone (P = 0.29, odds ratio = 1.964, confidence interval = 0.46-8.45). The data suggest that the genotype at intron 1 of IFNG might affect susceptibility to acute hepatitis in HEV infection, which warrants further elucidation in a larger sample and also functional studies.

Transforming growth factor-beta1 genotype in sporadic breast cancer patients from India: status of enhancer, promoter, 5'-untranslated-region and exon-1 polymorphisms

Transforming growth factor beta (TGF-beta) is an example for a large and still-growing family of growth factors. TGF-beta1 is known to act both as a tumour suppressor and as a stimulator of tumour progression. This study examines the relationship amongst putative enhancer, promoter, 5'-untranslated-region (UTR) and exon-1 polymorphisms of the TGF-beta1 gene (region I from -1881 to -1613; region II from -1410 to -1123, and region III from -55 to +176, as per human genome organisation (HUGO) nomenclature) in 26 breast cancer patients and 97 healthy control subjects. The germline and somatic status of the four known polymorphisms was ascertained, and a significant difference was observed for the germline C/T and T/T genotype distribution between patients and controls in comparison to C/C genotypes at position -1349 (chi2 = 6.193; P = 0.009). In addition to the somatic variations observed for some of the regions studied, in 10/26 (38%) sporadic breast cancer cases, a novel somatic mutation in codon 47 of exon 1 (GenBank accession number AY059373) was also detected in tumour samples. The risk of cancer was found to be significant (OR = 4.525) for the -1349 C/T and T/T genotype background, suggesting that this genetic background may act as a risk factor for sporadic breast cancer.

The relation between nutrition indices and age in patients on continuous ambulatory peritoneal dialysis receiving similar small solute clearances

OBJECTIVE

To analyze the effect of age on nutrition indices in subjects on the same continuous ambulatory peritoneal dialysis (CAPD) schedule.

METHODS

We analyzed 613 sets of clearance values and nutrition indices in 302 CAPD patients. Small solute clearances included urea clearance (Kt/Vurea) and creatinine clearance (Ccr). Nutrition indices included body mass index (BMI), serum albumin, urea and creatinine, 24-h urea nitrogen and creatinine excretion in urine plus dialysate, protein nitrogen appearance (PNA), PNA normalized by standard weight (nPNA), lean body mass (LBM) computed by creatinine kinetics, and LBM/Weight. CAPD subjects were classified in 4 age quartiles (Q): Group Q1, age 33.7 +/- 7.6 years, N = 149; group Q2, age 49.5 +/- 3.8 years, N = 158; group Q3, age 61.5 +/- 2.6 years, N = 154; and group Q4, age 72.1 +/- 5.4 years, N = 152. Group comparison was done by one-way ANOVA or chi-square. Predictors of low nutritional parameters were identified by logistic regression. Selected variables were compared by linear regression.

RESULTS

Mean Kt/Vurea and Ccr were above the current adequacy standards and did not differ between the age quartiles. In contrast, older quartiles had, in general, lower nutrition indices than younger quartiles. However, the youngest quartile had the lowest BMI. By logistic regression, young age was a predictor of low BMI, while advanced age was a predictor of low creatinine and urea nitrogen excretion, low nPNA, and low LBM/Weight. The regressions of nPNA on Kt/Vurea differed between the age quartiles. By these regressions, the youngest quartile had higher nPNA values for the same Kt/Vurea than the oldest quartile in the clinically relevant range of Kt/Vurea and nPNA values.

CONCLUSIONS

Nutrition indices are worse in older than in younger CAPD patients with the same small solute clearances. Nutrition of CAPD patients is adversely affected by age and requires special attention in the older age group.

Effects of uremic serum on isolated cardiac myocyte calcium cycling and contractile function

BACKGROUND

Diastolic dysfunction occurs in patients with chronic renal failure. Moreover, serum from uremic patients contains one or more inhibitors of the plasmalemmal Na,K-ATPase (sodium pump). We hypothesized that a circulating substance present in uremic sera contributes to both sodium pump inhibition and diastolic dysfunction.

METHODS

Serum samples were obtained from six patients with chronic renal failure and diastolic dysfunction.

RESULTS

Their serum samples caused marked inhibition of Na,K-ATPase purified from dog kidney at all concentrations studied (all P < 0.01) and also impaired ouabain-sensitive rubidium uptake by myocytes isolated from Sprague-Dawley rats (P < 0.01). These cardiac myocytes were studied for their contractile function with video-edge detection and calcium metabolism with indo-1 fluorescence spectroscopy after exposure to these uremic sera. These uremic sera caused increases in myocyte fractional shortening (P < 0.01) as well as an increase in the time constant of relengthening (P < 0.01). Examining the calcium transient, the time constant for calcium recovery was also increased (P < 0.01). Exposure of these cells to sera from age- and sex-matched healthy subjects did not result in significant changes in contraction or calcium cycling. Extracts of uremic serum samples inhibited isolated Na,K-ATPase whereas extracts of normal serum samples did not. The effect of uremic serum extracts on contractile function and calcium cycling were quite similar to that of intact serum or the addition of ouabain. Co-incubation of uremic serum extract with an antibody fragment directed against digoxin markedly attenuated the inhibition of Na,K-ATPase activity and completely prevented any effects on calcium cycling or contractile function.

CONCLUSION

These data show that one or more substances are present in uremic sera that acutely cause increased force of contraction and impaired recovery of cardiac myocyte calcium concentration as well as impaired relaxation. As these effects are similar to that seen with ouabain and can be prevented by co-incubation with an antibody fragment to digitalis, which also attenuates the sodium pump inhibitory effect, we suggest that this (these) substance(s) circulating in uremic sera and inhibiting the sodium pump also causes the acute diastolic dysfunction seen in our system.

Effects of enhanced oxygen release from hemoglobin by RSR13 in an acute renal failure model

BACKGROUND

Acute renal failure is believed to be caused, in some circumstances, by impaired oxygen delivery to the outer medulla. This study examined the effect of RSR13, a synthetic allosteric modifier of hemoglobin oxygen-binding affinity, on renal function in a setting of acute renal failure in rats.

METHODS

An in vivo model of acute renal failure in the rat produced by reduced renal mass, salt restriction, volume depletion, prostaglandin inhibition, and radiocontrast administration was used. A computer-based simulation of oxygen tensions along the nephron was utilized to interpret the findings. Mechanistic studies were subsequently performed using oxygen-sensitive electrodes and 31P nuclear magnetic resonance (NMR) spectroscopy to define the effect of RSR13 on renal function in the setting of compromised acute renal failure.

RESULTS

RSR13 did not attenuate acute renal failure in this model; rather, serum creatinine increased to a greater degree in the RSR13-treated rats than in rats receiving saline vehicle as the control (P < 0.05). Simulations explained this finding under conditions of severe medullary hypoxia. Mechanistic studies demonstrated marked worsening of medullary hypoxia following RSR13 under conditions similar to our experimental model. Furosemide pretreatment to reduce the imbalance between oxygen supply and demand markedly attenuated the basal-medullary hypoxia produced in the presence of indomethacin and RSR13 (P < 0.01). Additionally, 31P NMR studies demonstrated renal adenosine 5'-triphosphate (ATP) depletion in rats with acute renal failure treated with RSR13 (45% decrease, P < 0.01); again, this effect of RSR13 was completely prevented by pretreatment with furosemide.

CONCLUSIONS

Under conditions of severe renal medullary hypoxia, induced in part by indomethacin-mediated reductions in outer medullary blood flow, the administration of RSR13 can exacerbate acute renal dysfunction. However, reducing the rate of oxygen consumption by inhibiting sodium transport with furosemide pretreatment or post-treatment appears to be functionally protective.

A potential role for immune activation in hemodialysis hypotension

The necessary exposure of blood to biomembranes during hemodialysis has been viewed by many as an immunogenic challenge leading to an acute phase response. In this study we examined the relationship between hemodialysis-induced immune activation and intradialytic hypotension, using the acute phase reactant serum C-reactive protein (CRP) as a surrogate for immunogenic activation. The maximum percent change in mean arterial pressure (MAP) was found to correlate significantly with CRP (r = 0.67, p < 0.05) in nine consecutive patients with a history of symptomatic hypotension during hemodialysis. In contrast, no correlation was found between CRP and maximum percent change in MAP in eight consecutive hemodialysis patients without intradialytic hypotension. Since interleukin-6 (IL-6) is a major regulator of CRP, the relationship between these two proteins was examined. Plasma IL-6 levels were found to correlate both with CRP (r = 0.67, p < 0.05) and with mean maximum percent change in MAP (r = 0.70, p < 0.05) in hemodialysis patients with a prior history of hypotension. IL-6 levels did not correlate with CRP or blood pressure in the hemodynamically stable patients. The results suggest that immune activation working through IL-6, CRP and other cytokines may play a role in the pathogenesis of hemodialysis hypotension in some patients.

Spermicidal & contraceptive properties of Praneem polyherbal pessary

BACKGROUND & OBJECTIVES

Though a number of barrier methods and potent spermicides are available, most of these have nonoxynol-9 (N-9) as the active ingredient which is observed to cause inflammation and genital ulceration on repeated use. The present study was undertaken to develop a safe spermicide with conjoint microbicidal properties.

METHODS

A polyherbal pessary was formulated with purified ingredients from neem (Azadirachta indica) leaves, Sapindus mukerossi (pericarp of fruit) and Mentha citrata oil. Spermicidal action on human sperm was tested by Sander-Cramer slide test in vitro and by post coital tests in vivo. Contraceptive action was tested in rabbits.

RESULTS

The combination of the three herbal ingredients resulted in the potentiation of the spermicidal action by 8-folds. The post coital tests confirmed the spermicidal properties of the Praneem polyherbal pessary (PPP) in women with high cervical mucous score around mid estrus. It also prevented in most women the migration of sperm into the cervical mucous. In 15 rabbits studied pregnancy was prevented by the intravaginal administration of PPP, whereas 13 of the 15 animals in the control group became pregnant.

INTERPRETATION & CONCLUSION

The Praneem polyherbal pessary has potent spermicidal action on human sperm in vitro and in vivo. When applied in the vagina before mating, it prevented rabbits from becoming pregnant.

Renal clearances in continuous ambulatory peritoneal dialysis: differences between diabetic and non-diabetic subjects

We analyzed the effect of diabetes on the decline of residual renal function during the course of CAPD in a cross-sectional study including 105 diabetic subjects (41 women) who had 207 clearance studies and 125 non-diabetic subjects (50 women, 265 clearance studies). CAPD duration was 11.5+/-10.5 months in the diabetic group (DG) and 16.8+/-18.6 months in the non-diabetic group (NDG, P < 0.001). The DG had lower urine volume than the NDG (0.52+/-0.46 vs 0.61+/-0.50 L/24-h, P < 0.05), while urine-to-plasma concentration ratio was higher in the DG for creatinine (13.5+/-9.4 vs 11.5+/-11.0, P <0.05) and did not differ for urea. Weekly renal Kt/V urea (DG 0.51+/-0.57, NDG 0.53+/-0.49) and Ccr (DG 31.0+/-28.7 NDG 29.3+/-26.5 L/1.73 m2) did not differ. The slopes of the regressions of CAPD duration on renal clearances did not differ. These regressions allowed estimates of the time, from the onset of CAPD, at which renal clearances become negligible. These estimates differed for both urea clearance (DG 35.3, NDG 50.5 months) and creatinine clearance (DG 43.2, NDG 57.6 months). The slope of the regression of renal urea clearance on renal creatinine clearance was steeper in the DG, suggesting a higher renal creatinine clearance in the DG than in the NDG when renal urea clearance is the same in the two groups. Subtle differences in the rate of decline of renal function can be detected between diabetic and non-diabetic subjects on CAPD by detailed statistical analysis. These findings are supportive of the studies which have identified diabetes mellitus as a predictor of loss of residual renal function during the course of CAPD. In addition, the relationship between the renal urea and creatinine clearances differs between diabetic and nondiabetic subjects on CAPD. Therefore, the dose of CAPD required for adequate total clearances may differ between diabetic and non-diabetic subjects.

Effects of hypokalemia on cardiac growth

In neonatal myocytes grown in culture, reductions in extracellular potassium concentration produced a hypertrophic response as assessed by induction of early response genes, atrial natriuretic peptide and skeletal actin, and repression of the alpha3 isoform of the sodium pump in a dose dependent manner. The degree of alpha3 repression appeared to be dose dependent with decreases in media (K). Similarly, decreases in media potassium concentrations caused increases in cytosolic calcium concentration in a dose dependent manner; moreover these increases in cytosolic calcium concentration correlated quite well with repression of alpha3 expression. In contrast, although moderate reductions of potassium concentration induced upregulation of skACT and ANP, severely reduced potassium concentrations caused repression of skACT and ANP expression. In parallel studies performed in vivo, 3-5 weeks dietary K restriction induced molecular phenotypical changes similar to that seen in the neonatal myocyte model without demonstrable growth as assessed by the heart weight/body weight ratio. However, when rates subjected to dietary K restriction were subsequently subjected to acute aortic constriction, cardiac growth was greater than in rats fed a control diet. These data suggest that hypokalemia may produce molecular phenotypic alterations consistent with cardiac hypertrophy as well as contribute to hypertrophy in an in vivo model.

The Drosophila UBC9 homologue lesswright mediates the disjunction of homologues in meiosis I

BACKGROUND

In Saccharomyces cerevisiae and other organisms, the UBC9 (ubiquitin-conjugating 9) protein modifies the function of many different target proteins through covalent attachment of the ubiquitin-like protein SMT-3/SUMO.

RESULTS

Using a second-site suppression screen of a mutation in the nod locus with a variable meiotic phenotype, we have identified mutations in the Drosophila melanogaster UBC9 homologue, encoded by the gene lesswright (lwr). lwr mutations dominantly suppress the nondisjunction and cytological defects of female meiotic mutations that affect spindle formation. The lwr lethal phenotype is rescued by a Drosophila UBC9/lwr transgene.

CONCLUSIONS

We suggest that LWR mediates the dissociation of heterochromatic regions of homologues at the end of meiotic prophase I. Our model proposes that when there is less LWR protein, homologues remain together longer, allowing for more normal spindle formation in mutant backgrounds and therefore more accurate meiotic chromosome segregation.

Small-solute clearances in diabetic subjects on continuous ambulatory peritoneal dialysis: comparison to nondiabetic subjects

Normalized clearances for urea and creatinine were compared between 121 diabetic subjects (256 clearances) and 181 nondiabetic subjects (357 clearances) on continuous ambulatory peritoneal dialysis (CAPD) with four 2-L exchanges daily. Urea clearance was normalized by VWatson (Kt/Vur), while creatinine clearance was normalized by both VWatson (Kt/Vcr) and body surface area (Ccr). Height, weight, body water (V), and body surface area did not differ between the diabetic and the nondiabetic groups. Also, renal Kt/Vur, renal Kt/Vcr, renal Ccr, and peritoneal Kt/Vur did not differ between the groups. Weekly peritoneal Kt/Vcr (diabetic group 1.36 +/- 0.38, nondiabetic group 1.31 +/- 0.31, p = 0.048) and weekly peritoneal Ccr (diabetic group 47.6 +/- 11.0 L/1.73 m2, nondiabetic group 45.4 +/- 9.2 L/1.73 m2, p = 0.012) were both higher in diabetic subjects. The percentage of high/high-average transporters was higher in the diabetic group (64.9% vs 48.6% in nondiabetic group, p = 0.006). The following total (peritoneal + renal) weekly clearances were obtained: Kt/Vur, diabetic group 2.07 +/- 0.63, nondiabetic group 2.02 +/- 0.56, NS; Kt/Vcr, diabetic group 2.06 +/- 0.78, nondiabetic group 1.92 +/- 0.74, p = 0.026; Ccr, diabetic group 72.7 +/- 28.5 L/1.73 m2, nondiabetic group 67.2 +/- 26.4 L/1.73 m2, p = 0.013. Normalized total creatinine clearances are higher in diabetic subjects than nondiabetic subjects on the same CAPD schedule and with the same renal clearances of urea and creatinine and the same total Kt/Vur, because peritoneal creatinine clearances are higher in the diabetic subjects. This finding is caused by higher peritoneal transport in the diabetic subjects and is not an artifact caused by the normalization process.

Autologous transplantation of ex vivo expanded bone marrow cells grown from small aliquots after high-dose chemotherapy for breast cancer

The collection of small aliquots of bone marrow (BM), followed by ex vivo expansion for autologous transplantation may be less morbid, and more cost-effective, than typical BM or blood stem cell harvesting. Passive elimination of contaminating tumor cells during expansion could reduce reinoculation risks. Nineteen breast cancer patients underwent autotransplants exclusively using ex vivo expanded small aliquot BM cells (900-1200 x 10(6)). BM was expanded in media containing recombinant flt3 ligand, erythropoietin, and PIXY321, using stromal-based perfusion bioreactors for 12 days, and infused after high-dose chemotherapy. Correlations between cell dose and engraftment times were determined, and immunocytochemical tumor cell assays were performed before and after expansion. The median volume of BM expanded was 36.7 mL (range 15.8-87.0). Engraftment of neutrophils greater than 500/microL and platelets greater than 20,000/microL were 16 (13-24) and 24 (19-45) days, respectively; 1 patient had delayed platelet engraftment, even after infusion of back-up BM. Hematopoiesis is maintained at 24 months, despite posttransplant radiotherapy in 18 of the 19 patients. Transplanted CD34(+)/Lin(-) (lineage negative) cell dose correlated with neutrophil and platelet engraftment, with patients receiving greater than 2.0 x 10(5) CD34(+)/Lin(-) cells per kilogram, engrafting by day 28. Tumor cells were observed in 1 of the 19 patients before expansion, and in none of the 19 patients after expansion. It is feasible to perform autotransplants solely with BM cells grown ex vivo in perfusion bioreactors from a small aliquot. Engraftment times are similar to those of a typical 1000 to 1500 mL BM autotransplant. If verified, this procedure could reduce the risk of tumor cell reinoculation with autotransplants and may be valuable in settings in which small stem cell doses are available, eg, cord blood transplants. (Blood. 2000;95:2169-2174)

Normalization of clearances in peritoneal dialysis using a formula for body water derived from an end-stage renal disease population

OBJECTIVE

To compare body water (V) estimates from the Chertow formula (Vc), which was derived in an end-stage renal disease population, to V estimates from the Watson formulas (Vw) in continuous ambulatory peritoneal dialysis (CAPD) patients. To identify CAPD patients in whom Vc is preferred to Vw for clearance studies.

DESIGN

Retrospective analysis of clearance studies.

SETTING

Dialysis units of four academic medical centers.

PARTICIPANTS

302 subjects on CAPD.

INTERVENTION

613 clearance studies by standard methods.

MAIN OUTCOME MEASURES

Comparisons between Vc and Vw, and between urea clearance normalized by Vc [(KtVc)ur] and Vw [(Kt/Vw)ur].

RESULTS

Vc exceeded Vw by 3.5 +/- 1.6 L (p < 0.001), or 9.6% on average. This degree of overestimation of Vw is in the range of body water estimates found in CAPD subjects with severe volume overload (> 5% of body weight) in previous studies. Total (Kt/Nw)ur exceeded total (Kt/Vc)ur by 8.6%. By linear regression, Vc = -0.589 + (1.112 x Vw), r = 0.983. Vw exceeded Vc in only 12 studies. Young age, short height, low body weight, and low prevalence of diabetes characterized the studies with Vw > Vc. Total (Kt/Vw)ur was adequate (> or = 2.0 weekly) in 276 studies. Among these, 74 studies had inadequate total (Kt/Vc)ur (< 2.0 weekly). By logistic regression, the predictors of inadequate (Kt/Vc)ur, when (Kt/Vw)ur was adequate, included the presence of diabetes, great height, and long duration of CAPD.

CONCLUSIONS

Vc provides estimates of body water exceeding those provided by Vw in a great majority of CAPD patients. Consequently, approximately 25% of the clearance studies that are adequate when Vw is used as the normalizing parameter may be inadequate when Vc is used. Vc may provide a more appropriate estimate of body water than Vw in CAPD patients with volume overload.

Dependence of peritoneal clearances on body size in continuous ambulatory peritoneal dialysis: effect of the normalizing size indicator

In peritoneal dialysis (PD), small solute clearances are normalized by body water (V) and body surface area (BSA). The purpose of this study was to identify if V or BSA produced stronger associations between body size and normalized clearances. We studied the relationship between four size indicators (V, BSA, height, and weight) and either peritoneal urea clearance normalized to V (Kt/V(ur)) and BSA (C(ur)) or creatinine clearance normalized to V (Kt/V(cr)) and BSA (C(cr)). A total of 613 clearance studies were performed in subjects on continuous ambulatory peritoneal dialysis (CAPD) with four daily exchanges and a 2 L fill volume. As size increased, the normalized peritoneal clearances decreased in a nonlinear fashion (regression: y = b0 + b1x(-1), where x is a size indicator and y is a normalized clearance). Significant (p < 0.001) negative correlations were found between each normalized clearance and each size indicator. However, in each case, the correlation was higher when V, rather than BSA, was used. For example, BSA correlated more closely with K/V(ur)(-0.660) than C(ur)(-0.556), and also with Kt/V(cr)(-0.579) than C(cr)(-0.446). Normalized clearances are smaller in large subjects on CAPD because one mathematic determinant of the clearance, the drain volume (Dv) normalized by V (Dv/V) or BSA (DV/BSA), decreases as size increases. The relationship between Dv/V or Dv/BSA and the size indicators was studied by the same nonlinear regression model. The correlations of the size indicators with Dv/V were also consistently higher than the corresponding correlations with Dv/BSA. In subjects who were on the same PD schedule, the dependence of clearances on size was consistently higher when V, rather than BSA, was the normalizing parameter. Because prescription of the dose of PD is based on body size, there is a practical advantage by using V as the sole normalizing parameter for both urea and creatinine clearance.