Race, Rurality, and Suicidality in Children and Adolescents

INTRODUCTION

Suicide is among the leading causes of death in U.S. youth. Rural residency is a risk factor, but suicide variability by race/ethnicity is more nuanced. Early detection of suicidal ideation and intent are key components of prevention, but to the authors' knowledge, few prior studies have examined how rurality and race interact on youth suicidality. This study examined suicidality between White non-Hispanic versus non-White or Hispanic youth, as well as those who lived in rural versus non-rural areas.

METHODS

Cross-sectional analyses were conducted using data from youth age 5-17 years who had complete capture of their medical care in a Wisconsin healthcare system. Suicidality was extracted from medical records by screening for diagnoses indicative of suicidal attempt or ideation between 2017 and 2022. Race/ethnicity and rural residence were extracted from administrative records. Analyses were done in 2023.

RESULTS

The sample included 27,392 rural and 20,370 non-rural youth, with suicidality observed in 2% of participants. There was a significant interaction between rural residence and race/ethnicity (p=0.015). Non-White or Hispanic youth in rural areas had the highest risk of suicidality at 75 (CI: 57, 97) per 10,000. Non-White or Hispanic youth in non-rural areas had the lowest risk of suicidality at 38 (CI: 28, 52) per 10,000.

CONCLUSIONS

Racial/ethnic minority youth who lived in rural areas were more likely to experience suicidality as compared to their non-rural counterparts. Larger prospective studies are needed to identify causal elements of the rural environment that may hasten racial disparities in youth suicidality.

Medically Attended Suicidality in Youth Who Live on Farms

Suicides are increasing in U.S. youth, particularly in rural areas. The influence of farming, however, is unclear, as suicide rates are higher in individual adult farm workers, but lower in farming-reliant counties. Early recognition of suicidality (suicidal ideation, intent, or attempt) is a key element of prevention, but there are no prior studies comparing suicidality in farm vs. non-farm youth. The purpose of this study was to examine associations between farm/rural residence and suicidality. Medical records were reused from an existing cohort of child and adolescent patients under surveillance for agricultural injuries in a Wisconsin healthcare system. The sample included 2,010 youth who lived on farms and 51,900 youth who did not live on farms (57% rural). The outcome was medically attended suicidality in 2017-2022 per a composite of diagnoses for suicidal ideation, attempt, or intentional self-harm that presented to ambulatory, emergency, or inpatient care settings. Suicidality was observed in 0.8% of farm, 1.8% of non-farm rural, and 1.6% of non-farm non-rural youth. After covariate adjustment, farm youth had significantly lower odds of suicidality (adjusted odds ratio [aOR] [95% confidence interval; CI] = 0.55 [0.33, 0.91], P = .019), while non-farm rural youth had significantly greater odds of suicidality (aOR [CI] = 1.21 [1.05, 1.40], P = .007), relative to non-farm non-rural youth. Children and adolescents who live on farms are about half as likely to (medically) present for suicidality as compared to their non-farm counterparts, both rural and non-rural. Future research should identify causal suicide protection factors in farm youth.

Early development and adaptive functioning in children with Bardet-Biedl syndrome

This study had two aims. Aim one investigated achievement of 10 developmental milestones in children with Bardet-Biedl syndrome (BBS). Aim one data were derived from retrospective responses by caregivers of individuals with BBS who are enrolled in the Clinical Registry Investigating Bardet-Biedl syndrome (CRIBBS). CRIBBS is a natural history registry acquiring serial observations. Aim two investigated early adaptive skills using the Adaptive Behavior Assessment System (ABAS-II 0-5) completed by caregivers of children with BBS aged from 0 to 5. There were 652 individuals with milestone information (with some variability based on availability of information for specific milestones), and 101 individuals (including 95 among the 652) with ABAS-II information. Results revealed wide-ranging delays in adaptive skills, particularly in the domain of Self-Care. Expressive language appears to be the most frequently delayed developmental milestone. We found a difference by BBS genotype wherein individuals with BBS1 had higher adaptive/developmental scores than individuals with BBS10. Age also carried a significant association with adaptive skills diverging farther from a normative trajectory as children with BBS progress through early childhood.

Modeling longitudinal oral health status and pneumonia risk: secondary data analyses of an integrated dental-medical cohort

BACKGROUND

Mounting evidence indicates potential associations between poor oral health status (OHS) and increased pneumonia risk. Relative pneumonia risk was assessed in the context of longitudinally documented OHS.

METHODS

Electronic medical/dental patient data captured from 2007 through 2019 were retrieved from the integrated health records of Marshfield Clinic Health Systems. Participant eligibility initiated with an assessment of OHS, stratified into the best, moderate, or worst OHS groups, with the additional criterion of 'no pneumonia diagnosis in the past 90 days'. Pneumonia incidence was longitudinally monitored for up to 1 year from each qualifying dental visit. Models were assessed, with and without adjustment for prior pneumonia incidence, adjusted for smoking and subjected to confounding mitigation attributable to known pneumonia risk factors by applying propensity score analysis. Time-to-event analysis and proportional hazard modeling were applied to investigate relative pneumonia risk over time among the OHS groups.

RESULTS

Modeling identified associations between any incident pneumonia subtype and 'number of missing teeth' (p < 0.001) and 'clinically assessed periodontal status' (p < 0.01), which remained significant following adjustment for prior pneumonia incidence and smoking. The hazard ratio (HR) for 'any incident pneumonia' in the best OHS group for 'number of missing teeth' was 0.65, 95% confidence interval (CI) [0.54 - 0.79] (unadjusted) and 0.744, 95% CI [0.61 - 0.91] (adjusted). The HR for 'any incident pneumonia' in the best 'clinically assessed periodontal status' group was 0.72, 95% CI [0.58 - 0.90] (unadjusted) and 0.78, 95% CI [0.62 - 0.97] (adjusted).

CONCLUSION/CLINICAL RELEVANCE

Poor OHS increased pneumonia risk. Proactive attention of medical providers to patient OHS and health literacy surrounding oral-systemic disease association is vital, especially in high-risk populations.

COVID-19 vaccine coverage disparities in rural and farm children

BACKGROUND

The risks of severe outcomes associated with SARS-CoV-2 (COVID-19) are elevated in unvaccinated individuals. It remains crucial to understand patterns of COVID-19 vaccination, particularly in younger and remote populations where coverage often lags. This study examined disparities in COVID-19 vaccine coverage in farm children and adolescents.

METHODS

A cross-sectional analysis was conducted in patients of the Marshfield Clinic Health System (MCHS) in Wisconsin. The sample included children/adolescents age 5-17 years who were eligible for COVID-19 vaccine initiation for ≥ 90 days (as of September 30, 2022), stratified by those who lived vs did not live on a farm. Outcomes included COVID-19 vaccine initiation, series completion, and booster receipt. Multivariable regression was used to examine associations between COVID-19 vaccination and farm, as well as rural and non-rural, residence.

RESULTS

There were 47,104 individuals (5% farm residents) in the sample. Overall, 33% of participants initiated and 31% completed the COVID-19 vaccine series. After adjustment, farm residence was associated with significantly lower odds of COVID-19 vaccine initiation (aOR [95% CI] = 0.68 [0.61, 0.75], p < 0.001), series completion (aOR = 0.67 [0.60, 0.75], p < 0.001), and booster receipt (aOR = 0.73 [0.61, 0.88], p = 0.001). Secondary analyses found COVID-19 vaccine coverage was lowest in young children who lived on dairy farms.

CONCLUSIONS

COVID-19 vaccine coverage is low in north-central Wisconsin children and adolescents. Those who live on farms have significantly lower likelihood of COVID-19 vaccine initiation, series completion, and booster receipt compared to non-farm counterparts. Farm families are an underserved group and require more effective public health interventions designed to prevent COVID-19.

Mental health of agricultural adolescents and adults: Preliminary results of a five-year study

Background

Work-related stressors common to agriculture have been associated with adverse mental health outcomes among adult farmers and ranchers. However, the mental health status of agricultural youth is unknown, despite farm and ranch youth being exposed to the same occupational hazards as their adult counterparts. The objective of this study was to estimate the prevalence of symptoms of depression and anxiety among farm adults and their adolescent child and examine the correlation between symptoms of mental health conditions and financial indicators described in the Family Stress Model (FSM).

Methods

Farm families were recruited to participate in online surveys by mail, email, and social media. One adolescent and at least one adult from each family were invited to complete on online survey. Where available, validated instruments were used to collect mental health, stress, family dynamics, and household financial variables. Descriptive statistics were used to describe sample demographics and prevalence of symptoms of depression and anxiety. Pearson correlations describe associations between variables within the Family Stress Model.

Results

Farm families (N = 122) completed the online survey. The mean age of farm parents was 41.4 years (SD = 4.4) and the mean age of farm adolescents was 15.4 (1.2). A majority of farm parents and farm adolescents were male, 58.2% and 70.5%, respectively. The sample was primarily white, non-Hispanic. In this sample of farm parents and adolescents alike, 60% met the criteria for at least mild depression, based on the Patient Health Questionnaire-9 (PHQ-9) and Patient Health Questionnaire-A (PHQ-A). Similarly, among adolescents, 45.1% met the criteria for Generalized Anxiety Disorder (GAD), as did 54.9% of adults. As a measure of economic hardship, per capita income by itself showed relatively low correlations, even with other economic measures (r = 0.11 with negative financial events, r = 0.20 with financial needs, r = 0.17 with financial situation, and r = 0.27 with debt). Parent depressed mood was in turn highly associated with adolescent depression (r = 0.83), social anxiety (r = 0.54), and generalized anxiety (r = 0.69).

Conclusions

The results show a strong association between parent and adolescent mental health and parental depressed mood and debt. There is not a clear association between economic stress and mental health in this sample, but further work is needed to be done at a population level. Preliminary results are promising for application of the full Family Stress Model as we continue to accrue farm families into the study cohort.

Regional surveillance of medically-attended farm-related injuries in children and adolescents

Purpose

Due to numerous environmental hazards such as heavy machinery and large livestock, youth who live and work on farms are at high risk of injury, disability, and death. This study described a regional surveillance system for monitoring farm-related injuries in children and adolescents. As the risk of farm-related injuries are not exclusive to farm residents, trends in farm-related injuries over the previous 5 years were reported and compared between children/adolescents who did and did not live on farms in north-central Wisconsin.

Methods

A retrospective cohort of child and adolescent patients of the Marshfield Clinic Health System was assembled. Incident farm-related injuries, including from agricultural work or other activities in a farm environment, were extracted from medical records from 2017 through 2021. Generalized linear models were created to compare age- and sex-adjusted farm-related injury rates by year.

Results

There were 4,730 (5%) in-farm and 93,420 (95%) out-farm children and adolescents in the cohort. There were 65 incident farm-related injury cases in the in-farm group and 412 in the out-farm group. The annual incidence rate of farm-related injuries was higher in the in-farm group, but changes during the 5-year timeframe were not significant in either group. In the in-farm group, rates ranged from a high of 61.8 [95% confidence interval (CI): 38.3, 94.5] incident farm-related injuries per 10,000 children/adolescents in 2017 to a low of 28.2 (13.5, 51.9) injuries per 10,000 children/adolescents in 2018. In the out-farm group, rates ranged from 10.7 (8.3, 13.6) to 16.8 (13.7, 20.5) incident farm-related injuries per 10,000 children/adolescents per year between 2017 and 2021. The in-farm group had a higher proportion of injured males and heavy machinery injuries, while the out-farm group had more all-terrain vehicle injuries and pesticide poisonings.

Conclusion

Farm residency remains hazardous for children and adolescents, as injury rates were three times higher in the in-farm group and remained stable over 5 years. All-terrain vehicle injuries were high in both groups, and should be a priority in rural safety interventions. With additional adaptations to other states, this surveillance model could be scaled across other healthcare systems.

Hydrochlorothiazide use, sun exposure, and risk of keratinocyte cancer

Background

Keratinocyte cancer (KC) rates are increasing in the U.S., particularly in older age groups. Use of hydrochlorothiazide (HCTZ), due to its photosensitizing properties, and high sun exposure are two known NMSC risk factors, but their synergistic effects are undetermined. The purpose of this study was to examine the development of NMSC between adults who did and did not use HCTZ, as well as those with high and low sun exposure.

Methods

A retrospective case–control sample was assembled from adult patients in north-central Wisconsin (USA). Duration of HCTZ use and occupational sun exposure were extracted from electronic health records, along with a linked survey of lifetime sun exposure.

Results

There were 333 cases and 666 controls in the analytical sample. A significant main effect was observed for HCTZ duration in the full sample. Under low sun exposure, the odds of NMSC was 14% greater for each additional year of HCTZ use (aOR = 1.14 [1.11, 1.18], p < 0.001). In a sensitivity analysis of participants age 70 years and over, there was a borderline significant (p = 0.086) HCTZ use by high sun exposure interaction, suggesting modestly increased HCTZ risk in older, high sun exposure adults.

Conclusions

Consistent with prior studies, longer duration of HCTZ use was a predictor of NMSC in north-central Wisconsin adults. NMSC may be accelerated in HCTZ users with outdoor lifestyles, but future studies should attempt to further disaggregate specific effects of sun exposure time, HCTZ duration, and age on NMSC development.

Kidney Failure in Bardet-Biedl Syndrome

The aim of this study was to explore kidney failure (KF) in Bardet–Biedl syndrome (BBS), focusing on high‐risk gene variants, demographics, and morbidity. We employed the Clinical Registry Investigating BBS (CRIBBS) to identify 44 (7.2%) individuals with KF out of 607 subjects. Molecularly confirmed BBS was identified in 37 KF subjects and 364 CRIBBS registrants. KF was concomitant with recessive causal variants in 12 genes, with BBS10 the most predominant causal gene (26.6%), while disease penetrance was highest in SDCCAG8 (100%). Two truncating variants were present in 67.6% of KF cases. KF incidence was increased in genes not belonging to the BBSome or chaperonin‐like genes (p < 0.001), including TTC21B, a new candidate BBS gene. Median age of KF was 12.5 years, with the vast majority of KF occurring by 30 years (86.3%). Females were disproportionately affected (77.3%). Diverse uropathies were identified, but were not more common in the KF group (p = 0.672). Kidney failure was evident in 11 of 15 (73.3%) deaths outside infancy. We conclude that KF poses a significant risk for premature morbidity in BBS. Risk factors for KF include female sex, truncating variants, and genes other than BBSome/chaperonin‐like genes highlighting the value of comprehensive genetic investigation.

Systematic review of studies examining contribution of oral health variables to risk prediction models for undiagnosed Type 2 diabetes and prediabetes

Objective

To conduct systematic review applying “preferred reporting items for systematic reviews and meta‐analyses statement” and “prediction model risk of assessment bias tool” to studies examining the performance of predictive models incorporating oral health‐related variables as candidate predictors for projecting undiagnosed diabetes mellitus (Type 2)/prediabetes risk.

Materials and Methods

Literature searches undertaken in PubMed, Web of Science, and Gray literature identified eligible studies published between January 1, 1980 and July 31, 2018. Systematically reviewed studies met inclusion criteria if studies applied multivariable regression modeling or informatics approaches to risk prediction for undiagnosed diabetes/prediabetes, and included dental/oral health‐related variables modeled either independently, or in combination with other risk variables.

Results

Eligibility for systematic review was determined for seven of the 71 studies screened. Nineteen dental/oral health‐related variables were examined across studies. “Periodontal pocket depth” and/or “missing teeth” were oral health variables consistently retained as predictive variables in models across all systematically reviewed studies. Strong performance metrics were reported for derived models by all systematically reviewed studies. The predictive power of independently modeled oral health variables was marginally amplified when modeled with point‐of‐care biological glycemic measures in dental settings. Meta‐analysis was precluded due to high inter‐study variability in study design and population diversity.

Conclusions

Predictive modeling consistently supported “periodontal measures” and “missing teeth” as candidate variables for predicting undiagnosed diabetes/prediabetes. Validation of predictive risk modeling for undiagnosed diabetes/prediabetes across diverse populations will test the feasibility of translating such models into clinical practice settings as noninvasive screening tools for identifying at‐risk individuals following demonstration of model validity within the defined population.

Injuries and illnesses to children in commercial fishing in Alaska: A brief report

BACKGROUND

Commercial fishing is the most hazardous occupation in the United States. While the epidemiology of adult injuries and fatalities are well documented, injuries to children (<18 years old) are not described. The purpose of this report was to describe the characteristics of nonfatal injuries to children involved in commercial fishing.

METHODS

Nonfatal commercial fishing injuries to children were identified in the Alaska Fishermen's Fund. The Alaska Fishermen's Fund is an emergency fund payor of last resort. Data on nonfatal injuries to victims aged 17 or younger were analyzed. Descriptive statistics were used to characterize demographics and injury characteristics.

RESULTS

Forty-four nonfatal child injury claims were made between 2012 and 2016. The mean age at the time of claim was 15.6 years (SD = 1.8) and 84% were male. The most common types of injuries among children were sprains and strains and the most commonly injured body parts were upper extremities and the trunk. Most injuries occurred in salmon fisheries.

CONCLUSIONS

Children are participating in commercial fishing. Based on the results of this analysis, children are also experiencing occupational injuries. The results of this analysis underscore the need for additional safety and health information, guidance for supervisors, and intervention to prevent injuries to children participating in commercial fishing.

Bardet-Biedl syndrome: Weight patterns and genetics in a rare obesity syndrome

BACKGROUND

Bardet-Biedl syndrome (BBS) is a rare genetic disorder that severely inhibits primary cilia function. BBS is typified by obesity in adulthood, but pediatric weight patterns, and thus optimal periods of intervention, are poorly understood.

OBJECTIVES

To examine body mass differences by age, gender, and genotype in children and adolescents with BBS.

METHODS

We utilized the largest international registry of BBS phenotypes. Anthropometric and genetic data were obtained from medical records or participant/family interviews. Participants were stratified by age and sex categories. Genotype and obesity phenotype were investigated in a subset of participants with available data.

RESULTS

Height and weight measurements were available for 552 unique individuals with BBS. The majority of birth weights were in the normal range, but rates of overweight or obesity rapidly increased in early childhood, exceeding 90% after age 5. Weight z-scores in groups >2 years were above 2.0, while height z-scores approached 1.0, but were close to 0.0 in adolescents. Relative to those with the BBS10 genotype, the BBS1 cohort had a lower BMI z-score in the 2-5 and 6-11 age groups, with similar BMI z-scores thereafter. Children with biallelic loss of function (LOF) genetic variants had significantly higher BMI z-scores compared to missense variants.

CONCLUSION

Despite normal birth weight, most individuals with BBS experience rapid weight gain in early childhood, with high rates of overweight/obesity sustained through adolescence. Children with LOF variants are disproportionally affected. Our findings support the need for earlier recognition and initiation of weight management therapies in BBS.

A Contemporary Profile of the Mental Health of Girls from Farm and Non-Farm Environments

Background: The mental health of young people has become a public health priority in recent years. Many early symptoms of mental health disorders first appear during adolescence. The aim of this study was to develop a contemporary profile of the mental health of Canadian adolescent girls from farms and determine whether they differed from girls with non-farm backgrounds.Methods: Cross-sectional analyses of an established, school-based survey, the Health Behaviour in School-Aged Children (2014) were conducted. Study subjects were adolescent girls who reported living or working (n = 1,346) and not living or working (n = 13,158) on a farm and attending schools in rural, small, medium and large/metropolitan centers. Scales examining positive (prosocial behaviour, life satisfaction) and negative (psychological problems, overt risk-taking) mental health indicators were compared between the two groups of girls by grade and community size.Results: Both farm and non-farm girls in upper grades reported lower life satisfaction scores and higher scores for psychological problems and overt risking-taking compared to girls in lower grades. By community size, girls from farms in the most rural schools reported more positive mental health than non-farm girls, with the exception of overt risk-taking, where girls in grades 9-10 from the most rural backgrounds reported markedly higher levels of risk-taking, particularly girls from farms.Conclusions: This study identified differences in mental health of girls from farms as community size increases, with more positive indicators among girls in the most rural communities. However, across all community sizes, overt risk-taking was higher in girls from farms. Thus, it appears that agrarian culture and norms have both protective and negative effects on the mental health of girls from farms.

Effect of CYP4F2, VKORC1, and CYP2C9 in Influencing Coumarin Dose: A Single-Patient Data Meta-Analysis in More Than 15,000 Individuals

The cytochrome P450 (CYP)4F2 gene is known to influence mean coumarin dose. The aim of the present study was to undertake a meta-analysis at the individual patients level to capture the possible effect of ethnicity, gene-gene interaction, or other drugs on the association and to verify if inclusion of CYP4F2*3 variant into dosing algorithms improves the prediction of mean coumarin dose. We asked the authors of our previous meta-analysis (30 articles) and of 38 new articles retrieved by a systematic review to send us individual patients' data. The final collection consists of 15,754 patients split into a derivation and validation cohort. The CYP4F2*3 polymorphism was consistently associated with an increase in mean coumarin dose (+9% (95% confidence interval (CI) 7-10%), with a higher effect in women, in patients taking acenocoumarol, and in white patients. The inclusion of the CYP4F2*3 in dosing algorithms slightly improved the prediction of stable coumarin dose. New pharmacogenetic equations potentially useful for clinical practice were derived.

Sleep in Farm Adolescents

Purpose

The objectives were to: (1) describe sleep timing and patterns among adolescents who live or work on farms; (2) compare these sleep characteristics to those of nonfarm adolescents; (3) explore whether the above sleep and farm versus nonfarm differences varied by age and gender.

Methods

Participants were aged 11‐16 years and were abstracted from the 2014 Canadian Health Behaviour in School‐aged Children study. Records from 2,160 farm adolescents were frequency matched (by school, gender, and grade) to records from 2,210 nonfarm adolescents. Participants self‐reported their bedtimes and wake‐up times on weekdays and weekends.

Findings

Among farm adolescents, average nightly sleep duration (hours:minutes) ranged from 08:34 among 14‐ to 16‐year‐old girls to 09:21 among 11‐ to 13‐year‐old girls. Approximately 24% to 32% of farm adolescents did not meet minimal sleep duration targets. For 11‐ to 13‐year‐olds, sleep characteristics did not differ according to farm status. However, for 14‐ to 16‐year‐olds, farm adolescents had shorter sleep durations than nonfarm adolescents (23 minutes for boys, P = .02; 20 minutes for girls, P = .06). Furthermore, a greater proportion of 14‐ to 16‐year‐old farm boys had sleep duration values less than the recommended 8 hours/night (27.7% vs 19.6%, P = .05).

Conclusions

This study profiles the sleep experiences of 11‐ to 16‐year‐old farm adolescents. Almost 1 in 3 of these adolescents did not get adequate sleep. Older adolescents who lived or worked on a farm slept less than comparably aged nonfarm adolescents. This may reflect their participation in morning chores essential to the farm operation and may increase their injury risk.

Brand vs generic adverse event reporting patterns: An authorized generic-controlled evaluation of cardiovascular medications

WHAT IS KNOWN AND OBJECTIVE

Some public scepticism exists about generics in terms of whether brand and generic drugs produce identical outcomes. This study explores whether adverse event (AE) reporting patterns are similar between brand and generic drugs, using authorized generics (AGs) as a control for possible generic drug perception biases.

METHODS

Events reported to the FDA Adverse Event Reporting System from the years 2004-2015 were analysed. Drugs were classified as brand, AG or generic based on drug and manufacturer names. Reports were included if amlodipine, losartan, metoprolol extended release (ER) or simvastatin were listed as primary or secondary suspect drugs. Disproportionality analyses using the reporting odds ratio (ROR) assessed the relative rate of reporting labelled AEs compared to reporting these AEs with all other drugs. The Breslow-Day test compared RORs across brand, AG and generic. Interrupted time series analysis evaluated the impact of generic entry on reporting trends.

RESULTS AND DISCUSSION

Generics accounted for significant percentages of total U.S. reports, but AGs accounted for smaller percentages of reports, including for amlodipine (14.26%), losartan (1.48%), metoprolol ER (0.35%) and simvastatin (0.70%). Whereas the RORs were significantly different for multiple brand vs generic comparisons, the AG vs generic comparisons yielded fewer statistically significant findings. Namely, only the ROR for AG differed from generic for amlodipine with peripheral oedema (P < .01).

WHAT IS NEW AND CONCLUSION

Inconsistent reporting patterns were observed more between brand and generic compared with AG and generic. Use of AGs as a control for perception biases against generics is useful, but this approach can be limited by small AG report numbers. Requiring the manufacturer name to be printed on the prescription bottle or packaging could improve the accuracy of assignment for products being reported.

Comparison of Outcomes Following a Switch From a Brand to an Authorized Versus Independent Generic Drug

Authorized generics are identical in formulation to brand drugs, manufactured by the brand company but marketed as a generic. Generics, marketed by generic manufacturers, are required to demonstrate pharmaceutical and bioequivalence to the brand drug, but repetition of clinical trials is not required. This retrospective cohort study compared outcomes for generics and authorized generics, which serves as a generic vs. brand proxy that minimizes bias against generics. For the seven drugs studied between 1999 and 2014, 5,234 unique patients were on brand drugs prior to generic entry and 4,900 (93.6%) switched to a generic. During the 12 months following the brand-to-generic switch, patients using generics vs. authorized generics were similar in terms of outpatient visits, urgent care visits, hospitalizations, and medication discontinuation. The likelihood of emergency department (ED) visits was slightly higher for authorized generics compared with generics. These data suggest that generics were clinically no worse than their proxy brand comparators.

Mixed Approach Retrospective Analyses of Suicide and Suicidal Ideation for Brand Compared with Generic Central Nervous System Drugs

INTRODUCTION

Several different types of drugs acting on the central nervous system (CNS) have previously been associated with an increased risk of suicide and suicidal ideation (broadly referred to as suicide). However, a differential association between brand and generic CNS drugs and suicide has not been reported.

OBJECTIVES

This study compares suicide adverse event rates for brand versus generic CNS drugs using multiple sources of data.

METHODS

Selected examples of CNS drugs (sertraline, gabapentin, zolpidem, and methylphenidate) were evaluated via the US FDA Adverse Event Reporting System (FAERS) for a hypothesis-generating study, and then via administrative claims and electronic health record (EHR) data for a more rigorous retrospective cohort study. Disproportionality analyses with reporting odds ratios and 95% confidence intervals (CIs) were used in the FAERS analyses to quantify the association between each drug and reported suicide. For the cohort studies, Cox proportional hazards models were used, controlling for demographic and clinical characteristics as well as the background risk of suicide in the insured population.

RESULTS

The FAERS analyses found significantly lower suicide reporting rates for brands compared with generics for all four studied products (Breslow-Day P < 0.05). In the claims- and EHR-based cohort study, the adjusted hazard ratio (HR) was statistically significant only for sertraline (HR 0.58; 95% CI 0.38-0.88).

CONCLUSION

Suicide reporting rates were disproportionately larger for generic than for brand CNS drugs in FAERS and adjusted retrospective cohort analyses remained significant only for sertraline. However, even for sertraline, temporal confounding related to the close proximity of black box warnings and generic availability is possible. Additional analyses in larger data sources with additional drugs are needed.

Health and Well-Being Among Young People From Canadian Farms: Associations With a Culture of Risk-Taking

PURPOSE

To determine whether patterns of adolescent risk behavior in rural populations, and especially farm populations, are associated with negative indicators of adolescent health and well-being, beyond an established association between risk-taking and injury.

METHODS

The study base was Cycle 7 (2014) of the Canadian Health Behaviour in School-Aged Children study. Children aged 11-16 years (n = 2,565; 2,533 weighted) who reported living or working on farms were matched within schools in a 1:1 ratio with other rural children. We related a scale describing engagement in multiple risk behavior to a series of indicators of adolescent health and well-being.

FINDINGS

Farm children, particularly male farm children, showed the highest levels of risk behavior. Multiple risk behavior was strongly and consistently associated with negative indicators of general health, mental health (life satisfaction, psychosomatic symptoms), and academic performance in all subpopulations.

CONCLUSIONS

Adolescent risk behavior in rural populations, and especially farm populations, is common and associated with a variety of negative indicators of adolescent health and well-being. We speculate that the origins of this risk-taking lifestyle surround cultural definitions of self and identity, which have both protective and negative effects.

Mutational and biochemical findings in adults with persistent hypophosphatasemia

A majority of adults with persistently low serum alkaline phosphatase values carry a pathogenic or likely pathogenic variant in the ALPL gene and also have elevated alkaline phosphatase substrate values in serum and urine. These adults may fall within the spectrum of the adult form of hypophosphatasia.

INTRODUCTION

The primary objective of this study was to determine what proportion of adults with persistently low serum alkaline phosphatase values (hypophosphatasemia) harbor mutations in the ALPL gene or have elevated alkaline phosphatase (ALP) substrates. Some adults with persistent hypophosphatasemia share clinical and radiographic features with the adult form of hypophosphatasia (HPP). In HPP, ALPL mutations result in persistent hypophosphatasemia and ALP substrate accumulation in plasma (pyridoxal-5-phosphate (PLP)) and urine (phosphoethanolamine (PEA)).

METHODS

Biochemical analyses, including serum ALP activity, bone-specific ALP, plasma PLP, and urine PEA, were performed in adults with persistent hypophosphatasemia. Mutational analyses were performed using PCR and Sanger sequencing methods. Gene variants were classified as pathogenic (P), likely pathogenic (LP), variants of uncertain significance (VUS), likely benign (LB), and benign (B). P and LP variants were further grouped as "Positive ALPL variants" and LB and B grouped as "Negative ALPL variants."

RESULTS

Fifty subjects completed all mutational and biochemical analyses. Sixteen percent carried only Negative ALPL variants. Of the remaining 42 subjects, 67% were heterozygous for a P variant, 19% for an LP variant, and 14% for a VUS. Biochemical results were highly inter-correlated and consistent with the expected inverse relationship between ALP and its substrates. Subjects harboring Positive ALPL variants showed lower ALP and BSAP and higher PLP and PEA values compared with subjects harboring only Negative ALPL variants. Approximately half of all subjects harboring Positive ALPL variants or ALPL VUS showed elevations in plasma PLP, and three quarters showed elevations in urine PEA.

CONCLUSION

Adults with persistent hypophosphatasemia frequently harbor ALPL mutations and have elevated ALP substrates. These adults may fall within the spectrum of the adult form of hypophosphatasia. Clinicians should take note of persistent hypophosphatasemia in their patients and be cautious in prescribing bisphosphonates when present.

Integrating Agricultural Injury Prevention with Rural Pediatrics: A Pilot Assessment

BACKGROUND

Childhood agricultural injuries are an important public health problem. Pediatricians are a trusted source of expertise in children's health and safety and could serve as a sphere of influence to augment child agricultural injury prevention efforts. The purpose of this pilot study was to begin to explore the perspectives of pediatricians in a large rural health clinic about addressing child agricultural injury prevention within their practice.

METHODS

Structured interviews were conducted with nine pediatricians who maintain a clinical practice of at least 2 days a week and care for newborns through adolescents. Detailed interviewer notes were reviewed and summarized.

RESULTS

Rural pediatricians readily acknowledge substantial numbers of farm children in their practice. In general, these providers: (1) recognize farming environments as a safety risk and see agricultural injury prevention as an important topic to be addressed with their patients, (2) are comfortable discussing the topic, but seldom actually initiate such conversations, and (3) doubt farm parents would be receptive to integrating agricultural injury prevention into a rural pediatric practice.

CONCLUSION

While rural pediatricians recognize child safety risks in farm environments, they are reluctant to actually initiate this conversation with parents. Future research should explore both pediatricians' hesitancy to discuss agricultural injury prevention and farm parents' readiness for integrating the topic into pediatric primary care visits. Such would help to assess the viability of pediatricians as a sphere of influence for augmenting child agricultural injury prevention efforts.

Comparison of brand versus generic antiepileptic drug adverse event reporting rates in the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS)

OBJECTIVE

Despite the cost saving role of generic anti-epileptic drugs (AEDs), debate exists as to whether generic substitution of branded AEDs may lead to therapeutic failure and increased toxicity. This study compared adverse event (AE) reporting rates for brand vs. authorized generic (AG) vs. generic AEDs. Since AGs are pharmaceutically identical to brand but perceived as generics, the generic vs. AG comparison minimized potential bias against generics.

METHODS

Events reported to the U.S. Food and Drug Administration Adverse Event Reporting System between January 2004 to March 2015 with lamotrigine, carbamazepine, and oxcarbazepine listed as primary or secondary suspect were classified as brand, generic, or AG based on the manufacturer. Disproportionality analyses using the reporting odds ratio (ROR) assessed the relative rate of reporting of labeled AEs compared to reporting these events with all other drugs. The Breslow-Day statistic compared RORs across brand, AG, and other generics using a Bonferroni-corrected P<0.01.

RESULTS

A total of 27,150 events with lamotrigine, 13,950 events with carbamazepine, and 5077 events with oxcarbazepine were reported, with generics accounting for 27%, 41%, and 32% of reports, respectively. Although RORs for the majority of known AEs were different between brand and generics for all three drugs of interest (Breslow-Day P<0.001), RORs generally were similar for AG and generic comparisons. Generic lamotrigine and carbamazepine were more commonly involved in reports of suicide or suicidal ideation compared with the respective AGs based on a multiple comparison-adjusted P<0.01.

SIGNIFICANCE

Similar AED reporting rates were observed for the AG and generic comparisons for most outcomes and drugs, suggesting that brands and generics have similar reporting rates after accounting for generic perception biases. Disproportional suicide reporting was observed for generics compared with AGs and brand, although this finding needs further study.

Social environments, risk-taking and injury in farm adolescents

Background

Farm environments are especially hazardous for young people. While much is known about acute physical causes of traumatic farm injury, little is known about social factors that may underlie their aetiology.

Objectives

In a nationally representative sample of young Canadians aged 11–15 years, we described and compared farm and non-farm adolescents in terms of the qualities of their social environments, engagement in overt multiple risk-taking as well as how such exposures relate aetiologically to their reported injury experiences.

Methods

Cross-sectional analysis of survey reports from the 2014 (Cycle 7) Canadian Health Behaviour in School-Aged Children study was conducted. Children (n=2567; 2534 weighted) who reported living or working on farms were matched within schools in a 1:1 ratio with children not living or working on farms. Scales examining quality of social environments and overt risk-taking were compared between the two groups, stratified by gender. We then related the occurrence of any serious injury to these social exposures in direct and interactive models.

Results

Farm and non-farm children reported social environments that were quite similar, with the exception of overt multiple risk-taking, which was demonstrably higher in farm children of both genders. Engagement in overt risk-taking, but not the other social environmental factors, was strongly and consistently associated with risks for serious injury in farm as well as non-farm children, particularly among males.

Conclusions

Study findings highlight the strength of associations between overt multiple risk-taking and injury among farm children. This appears to be a normative aspect of adolescent farm culture.

A Comparison of Women's Collegiate and Girls' High School Volleyball Injury Data Collected Prospectively Over a 4-Year Period

BACKGROUND

There is a relative paucity of research examining the sport-specific injury epidemiology of high school and collegiate volleyball athletes. Moreover, differences in study methodology frequently limit our ability to compare and contrast injury data collected from selected populations.

HYPOTHESIS

There are differences between the injury patterns characteristic of high school and collegiate female volleyball athletes.

STUDY DESIGN

Retrospective clinical review.

LEVEL OF EVIDENCE

Level 3.

METHODS

We statistically analyzed injury incidence and outcome data collected over a 4-year interval (2005-2006 to 2008-2009) by 2 similar injury surveillance systems, the National Collegiate Athletic Association's Injury Surveillance System (NCAA ISS) and the High School Reporting Injuries Online (HS RIO). We compared diagnoses, anatomic distribution of injuries, mechanisms of injury, and time lost from training or competition between high school and collegiate volleyball athletes.

RESULTS

The overall volleyball-related injury rate was significantly greater among collegiate athletes than among high school athletes during both competition (injury rate ratio, 2.9; 95% CI, 2.5-3.4) and practice (injury rate ratio, 3.5; 95% CI, 3.1-3.9). Collegiate athletes had a higher rate of ankle sprain, knee injury, and shoulder injury. Concussions represented a relatively high percentage of injuries in both populations (5.0% of total NCAA ISS injuries vs 4.8% of total HS RIO injuries, respectively).

CONCLUSION

The data suggest that although similar, there were distinct differences between the injury patterns of the 2 populations. Compared with high school volleyball players, collegiate athletes have a higher rate of acute time loss injury as well as overuse time loss injury (particularly patellar tendinosis). Concussions represented a significant and worrisome component of the injury pattern for both study populations.

CLINICAL RELEVANCE

The injury data suggest that important differences exist in the injury patterns of female high school compared with collegiate volleyball athletes. Consideration of the specific injury patterns may be helpful in future prevention efforts.

Quantification of oxycodone and morphine analytes in urine: Assessment of adherence

OBJECTIVE

To use urine drug testing (UDT) results and other covariates to develop a model for the assessment of opioid medication prescription adherence.

DESIGN

Retrospective study.

SETTING

The Pain Management Clinic at one center of a large, private, multispecialty healthcare system (consisting of 52 regional centers) in northcentral and western Wisconsin.

PARTICIPANTS

Seven hundred thirty-three Pain Management Clinic patients with an opioid prescription and UDT between June 1, 2007 and May 17, 2010. UDT results were available for 2,615 individual drug screens from 2,364 urine samples.

INTERVENTION

Patient characteristics, drug dosage, quantitative urine creatinine and drug/analyte levels, and reported adherence/nonadherence were abstracted from the electronic medical record.

MAIN OUTCOME MEASURES

Adherence was categorized for all UDT results using an objective set of criteria. Drug adherence was modeled excluding samples for clinically observed adherence issues, detection of illicit substances, diagnosed addictive disorders, and/or metabolic reasons.

RESULTS

Considerable variability was observed for primary urine analytes, even among those prescribed the same dose and believed to be adherent and free of confounding medical issues. For all medications evaluated, only urine creatinine contributed significantly (p < 0.0001) to predictive models of adherence based on dose alone. Simulated underuse and review of identified overuse and underuse suggest that this model could provide useful adherence information.

CONCLUSION

Predictive models based on urine analyte levels and clinical covariates, particularly urine creatinine, may be clinically useful for assessing opioid adherence. Future work should evaluate whether genetics or other factors can improve predictive accuracy of these models.

Biology-Driven Gene-Gene Interaction Analysis of Age-Related Cataract in the eMERGE Network

Bioinformatics approaches to examine gene-gene models provide a means to discover interactions between multiple genes that underlie complex disease. Extensive computational demands and adjusting for multiple testing make uncovering genetic interactions a challenge. Here, we address these issues using our knowledge-driven filtering method, Biofilter, to identify putative single nucleotide polymorphism (SNP) interaction models for cataract susceptibility, thereby reducing the number of models for analysis. Models were evaluated in 3,377 European Americans (1,185 controls, 2,192 cases) from the Marshfield Clinic, a study site of the Electronic Medical Records and Genomics (eMERGE) Network, using logistic regression. All statistically significant models from the Marshfield Clinic were then evaluated in an independent dataset of 4,311 individuals (742 controls, 3,569 cases), using independent samples from additional study sites in the eMERGE Network: Mayo Clinic, Group Health/University of Washington, Vanderbilt University Medical Center, and Geisinger Health System. Eighty-three SNP-SNP models replicated in the independent dataset at likelihood ratio test P < 0.05. Among the most significant replicating models was rs12597188 (intron of CDH1)-rs11564445 (intron of CTNNB1). These genes are known to be involved in processes that include: cell-to-cell adhesion signaling, cell-cell junction organization, and cell-cell communication. Further Biofilter analysis of all replicating models revealed a number of common functions among the genes harboring the 83 replicating SNP-SNP models, which included signal transduction and PI3K-Akt signaling pathway. These findings demonstrate the utility of Biofilter as a biology-driven method, applicable for any genome-wide association study dataset.

Reinitiating warfarin: relationships between dose and selected patient, clinical and hospital measures

BACKGROUND

Warfarin is an oral anticoagulant used in the long-term treatment/prevention of venothromboembolic disease. Patients undergoing elective surgical and non-surgical procedures may require temporary warfarin discontinuation followed by reinitiation after their procedure. Because little information is available regarding best methods for warfarin reinitiation, we investigated current practices to inform management decisions.

METHODS

Subjects were required to have a known and stable warfarin dose prior to discontinuation, which was operationalized by requiring, within 7-days prior to discontinuation, that they have at least one INR in therapeutic range (2.0-3.5), no INR(s) out of range, and no more than a 15% change in warfarin dose. Stable dose prior to discontinuation was defined as the average daily dose received in the 7 days immediately prior to discontinuation. Reinitiation dose was defined as the average daily dose received in the first 3 days after warfarin was restarted. Subjects were divided into three groups based on whether they received approximately the same, a higher, or a lower dose at reinitiation and were also grouped by calendar time into three distinct periods that reflected differing levels of availability of electronic and patient care data that may impact reinitiation dose decisions. These groupings facilitated analyses and descriptions of trends in reinitiation dosing and supported other analyses, including tests for association between dose group and selected subject demographic, clinical, medication and hospitalization measures. All study data were abstracted from Marshfield Clinic electronic patient care and administrative databases and electronic patient care databases from Ministry St. Joseph's Hospital (Marshfield, WI).

RESULTS

We identified 205 subjects with warfarin temporarily discontinued between 1994 and 2012: 99 subjects in same dose group, 32 subjects in the low group, and 74 subjects in the high group. Because relatively wide differences were observed in the proportion of same dose subjects during more recent years (2007-2012) compared to earlier years (54% vs 35%), we focused our analyses on this recent period, which included 140 subjects. Review of physician notes and other documents yielded virtually no information about reasons for reinitiation dose decisions. In addition, tests for association between reinitiation dose group and subject demographic, clinical, medication and hospital measures were uniformly uninformative.

CONCLUSIONS

We observed varied dosing strategies for reinitiating patients on warfarin and, in more recent years, an apparent trend toward reinitiating patients on the same dose. However we could not associate dosing strategy with specific patient demographic, clinical, medication or hospital factors. Many factors influence whether a physician reinitiates a patient at a different dose than his/her prior stable warfarin dose. However, in the absence of clinical indications for modification, we believe patients with a previously established effective dose should be reinitiated at that same dose following temporary warfarin discontinuation.

Factors that affect rate of INR decline after warfarin discontinuation

BACKGROUND

Despite vast literature on warfarin, optimal strategies for temporarily discontinuing and restarting warfarin have not been established. To improve warfarin discontinuation processes, we investigated known medical and genetic factors that influence stable warfarin dose to determine how well they predict the time until patients become subtherapeutic after discontinuing warfarin.

METHODS

This was a retrospective cohort study of patients who temporarily discontinued warfarin before an elective procedure andhad at least 2 international normalized ratio (INR) values available during the discontinuation period. Data abstracted included date of discontinuation, warfarin dose, INR values, body surface area, gender, age, indication for warfarin, current medications, eGFR, and presence of bridging therapy with heparin. DNA variants were tested in CYP2C9, VKORC1, and CYP4F2 genes. Subjects were excluded if they received vitamin K, fresh frozen plasma, or prothrombin complexes to reverse anticoagulation. Asymptotic regression models were used to approximate decline in INR during warfarin clearance. Spearman correlations and Kruskal-Wallis tests were used to characterize associations of model estimates with quantitative variables and for group comparisons, respectively.

RESULTS

Other than the expected association with baseline INR, correlations of model parameter estimates with clinical variables were generally weak and not statistically significant. The strongest associations with slope were with serum creatinine and eGFR. There were no significant associations with CYP2C9, VKORC1, or CYP4F2 DNA variants, but there were few subjects combined in the nonwild groups for CYP2C9. Estimated slope showed moderate correlation with observed dose.

CONCLUSION

Known clinical and genetic predictors of therapeutic dose were not found to be strongly associated with the slope of INR decline after warfarin discontinuation.

Relational machine learning for electronic health record-driven phenotyping

OBJECTIVE

Electronic health records (EHR) offer medical and pharmacogenomics research unprecedented opportunities to identify and classify patients at risk. EHRs are collections of highly inter-dependent records that include biological, anatomical, physiological, and behavioral observations. They comprise a patient's clinical phenome, where each patient has thousands of date-stamped records distributed across many relational tables. Development of EHR computer-based phenotyping algorithms require time and medical insight from clinical experts, who most often can only review a small patient subset representative of the total EHR records, to identify phenotype features. In this research we evaluate whether relational machine learning (ML) using inductive logic programming (ILP) can contribute to addressing these issues as a viable approach for EHR-based phenotyping.

METHODS

Two relational learning ILP approaches and three well-known WEKA (Waikato Environment for Knowledge Analysis) implementations of non-relational approaches (PART, J48, and JRIP) were used to develop models for nine phenotypes. International Classification of Diseases, Ninth Revision (ICD-9) coded EHR data were used to select training cohorts for the development of each phenotypic model. Accuracy, precision, recall, F-Measure, and Area Under the Receiver Operating Characteristic (AUROC) curve statistics were measured for each phenotypic model based on independent manually verified test cohorts. A two-sided binomial distribution test (sign test) compared the five ML approaches across phenotypes for statistical significance.

RESULTS

We developed an approach to automatically label training examples using ICD-9 diagnosis codes for the ML approaches being evaluated. Nine phenotypic models for each ML approach were evaluated, resulting in better overall model performance in AUROC using ILP when compared to PART (p=0.039), J48 (p=0.003) and JRIP (p=0.003).

DISCUSSION

ILP has the potential to improve phenotyping by independently delivering clinically expert interpretable rules for phenotype definitions, or intuitive phenotypes to assist experts.

CONCLUSION

Relational learning using ILP offers a viable approach to EHR-driven phenotyping.

Development and validation of an electronic phenotyping algorithm for chronic kidney disease

Twenty-six million Americans are estimated to have chronic kidney disease (CKD) with increased risk for cardiovascular disease and end stage renal disease. CKD is frequently undiagnosed and patients are unaware, hampering intervention. A tool for accurate and timely identification of CKD from electronic medical records (EMR) could improve healthcare quality and identify patients for research. As members of eMERGE (electronic medical records and genomics) Network, we developed an automated phenotyping algorithm that can be deployed to identify rapidly diabetic and/or hypertensive CKD cases and controls in health systems with EMRs It uses diagnostic codes, laboratory results, medication and blood pressure records, and textual information culled from notes. Validation statistics demonstrated positive predictive values of 96% and negative predictive values of 93.3. Similar results were obtained on implementation by two independent eMERGE member institutions. The algorithm dramatically outperformed identification by ICD-9-CM codes with 63% positive and 54% negative predictive values, respectively.

Type 2 diabetes mellitus, glycemic control, and cancer risk

Type 2 diabetes mellitus is characterized by prolonged hyperinsulinemia, insulin resistance, and progressive hyperglycemia. Disease management relies on glycemic control through diet, exercise, and pharmacological intervention. The goal of the present study was to examine the effects of glycemic control and the use of glucose-lowering medication on the risk of breast, prostate, and colon cancer. Patients diagnosed with type 2 diabetes mellitus (N=9486) between 1 January 1995 and 31 December 2009 were identified and data on glycemic control (hemoglobin A1c, glucose), glucose-lowering medication use (insulin, metformin, sulfonylurea), age, BMI, date of diabetes diagnosis, insurance status, comorbidities, smoking history, location of residence, and cancer diagnoses were electronically abstracted. Cox proportional hazards regression modeling was used to examine the relationship between glycemic control, including medication use, and cancer risk. The results varied by cancer type and medication exposure. There was no association between glycemic control and breast or colon cancer; however, prostate cancer risk was significantly higher with better glycemic control (hemoglobin A1c ≤ 7.0%). Insulin use was associated with increased colon cancer incidence in women, but not with colon cancer in men or breast or prostate cancer risk. Metformin exposure was associated with reduced breast and prostate cancer incidence, but had no association with colon cancer risk. Sulfonylurea exposure was not associated with risk of any type of cancer. The data reported here support hyperinsulinemia, rather than hyperglycemia, as a major diabetes-related factor associated with increased risk of breast and colon cancer. In contrast, hyperglycemia appears to be protective in the case of prostate cancer.

Electronic medical records and genomics (eMERGE) network exploration in cataract: several new potential susceptibility loci

PURPOSE

Cataract is the leading cause of blindness in the world, and in the United States accounts for approximately 60% of Medicare costs related to vision. The purpose of this study was to identify genetic markers for age-related cataract through a genome-wide association study (GWAS).

METHODS

In the electronic medical records and genomics (eMERGE) network, we ran an electronic phenotyping algorithm on individuals in each of five sites with electronic medical records linked to DNA biobanks. We performed a GWAS using 530,101 SNPs from the Illumina 660W-Quad in a total of 7,397 individuals (5,503 cases and 1,894 controls). We also performed an age-at-diagnosis case-only analysis.

RESULTS

We identified several statistically significant associations with age-related cataract (45 SNPs) as well as age at diagnosis (44 SNPs). The 45 SNPs associated with cataract at p<1×10(-5) are in several interesting genes, including ALDOB, MAP3K1, and MEF2C. All have potential biologic relationships with cataracts.

CONCLUSIONS

This is the first genome-wide association study of age-related cataract, and several regions of interest have been identified. The eMERGE network has pioneered the exploration of genomic associations in biobanks linked to electronic health records, and this study is another example of the utility of such resources. Explorations of age-related cataract including validation and replication of the association results identified herein are needed in future studies.

The relationship between childhood BMI and adult serum cholesterol, LDL, and ankle brachial index

OBJECTIVE

Effects of childhood overweight may persist into adulthood. We assessed the effect of childhood overweight on cardiovascular disease high risk factor levels in the same participants as adults, after controlling for adult body mass index (BMI) status.

DESIGN

A subset of participants in an observational study (Heartwatch) were contacted approximately 26-27 years after initial enrollment to participate in a follow-up study on the long-term effects of childhood overweight. During follow-up, BMI, waist:hip circumference (WHC), blood pressure (BP), serum lipids, and ankle brachial index (ABI) were measured; additional BMI measures throughout childhood were obtained as available from the electronic medical record. Primary outcomes were ABI and serum low density lipoprotein (LDL).

SETTING

The 1982 Heartwatch study was conducted with children participants living in Marshfield, Wisconsin; follow-up included original participants who were re-contacted and agreed to be enrolled.

PARTICIPANTS

Participants were a stratified random sample of eligible participants in the original 1982 Heartwatch study. Of the original 3106 participants, 647 adult participants completed follow-up exams.

RESULTS

Among males with 1982 BMI ≥ 85(th) percentile, adult BMI, WHC, (both P ≤ 0.001), ABI (P = 0.001), total cholesterol (P = 0.01), LDL (P = 0.003) and BP (P < 0.02) were higher in 2008-2009 as compared to males with 1982 BMI < 85(th) percentile. Among females, BMI, BP and WHC (all P < 0.001) were higher in 2008-2009. BMI in 1982 and 2008-2009 were correlated [r = 0.56 (males); 0.58 (females), P < 0.001]. 2008-2009 BMI was more strongly correlated with 2008-2009 measures of ABI (r = 0.16, P = 0.006, males) and high LDL [r = 0.18, P = 0.002 (males); r = 0.11, P = 0.046 (females)]. 1982 BMI was not independently associated with ABI or LDL after adjusting for adult BMI.

CONCLUSION

In a cohort studying childhood and adult overweight, childhood BMI was associated with health outcomes relating to cardiovascular disease in adulthood. However, childhood BMI was not independently related to LDL-C or ABI levels in adulthood after accounting for adult BMI. Longitudinal measurements of BMI and other health risk factors were not found to improve accuracy of models for high cardiovascular disease risk factor levels.

Asymmetry in noise-induced hearing loss: evaluation of two competing theories

Competing theories exist about why asymmetry is observed in noise-induced hearing loss (NIHL). We evaluated these theories using a cohort of young workers studied over 16 years. The study aim was to describe and evaluate patterns of hearing loss and asymmetry by gender, agricultural exposure and gunfire exposure. This was a secondary analysis of data collected from young adults during follow-up of a randomized controlled trial. This follow-up study evaluated long-term effects of a hearing conservation intervention for rural students. The sample consisted of 392 of 690 participants from the original trial. In total, 355 young adults (aged 29-33 years) completed baseline and follow-up noise exposure surveys and clinical audiometric examinations. Data are displayed graphically as thresholds by frequency and ear and degree of asymmetry between ears (left minus right). In the primary group comparisons, low and high frequency averages and mean high frequency asymmetry were analyzed using mixed linear models. At frequencies >2000 Hz, men showed more hearing loss, with greater asymmetry and a different asymmetry pattern, than women. For men with documented hearing loss, there was a trend toward increasing asymmetry with increasing levels of hearing loss. Asymmetry at high frequencies varied substantially by level of shooting exposure. While "head shadowing" is accepted as the primary explanation for asymmetric hearing loss in the audiologic and related public health literature, our findings are more consistent with physiological differences as the primary cause of asymmetric hearing loss, with greater susceptibility to NIHL in the left ear of men.

Clinical and radiographic findings in adults with persistent hypophosphatasemia

A serum alkaline phosphatase value below the age-adjusted lower limits of normal (hypophosphatasemia) is uncommonly encountered in clinical practice. The electronic and paper medical records of 885,165 patients treated between 2002 and 2012 at a large, rural, multispecialty health clinic were interrogated to estimate the prevalence and characterize the clinical and radiographic findings of adults whose serum alkaline phosphatase was almost always low (persistent hypophosphatasemia). We hypothesized that some of these patients might harbor previously unrecognized hypophosphatasia, a rare, inherited condition of impaired mineralization of bones and teeth. Persistent hypophosphatasemia (serum alkaline phosphatase ≤ 30 IU/L) was found in 1 of 1544 adult patients. These adult patients had more crystalline arthritis, orthopedic surgery, chondrocalcinosis, calcific periarthritis, enthesopathy, and diffuse idiopathic skeletal hyperostosis than a general adult patient population. A gender effect was observed. The clinical and radiographic findings of adult patients with persistent hypophosphatasemia resemble those of the adult form of hypophosphatasia. Clinicians should take notice of persistent hypophosphatasemia, consider the diagnosis of hypophosphatasia, and be cautious when considering potent anti-remodeling therapy in these adults. This population warrants further evaluation.

A novel method for studying the temporal relationship between type 2 diabetes mellitus and cancer using the electronic medical record

Background

We developed an algorithm for the identification of patients with type 2 diabetes and ascertainment of the date of diabetes onset for examination of the temporal relationship between diabetes and cancer using data in the electronic medical record (EMR).

Methods

The Marshfield Clinic EMR was searched for patients who developed type 2 diabetes between January 1, 1995 and December 31, 2009 using a combination of diagnostic codes and laboratory data. Subjects without diabetes were also identified and matched to subjects with diabetes by age, gender, smoking history, residence, and date of diabetes onset/reference date.

Results

The final cohort consisted of 11,236 subjects with and 54,365 subjects without diabetes. Stringent requirements for laboratory values resulted in a decrease in the number of potential subjects by nearly 70%. Mean observation time in the EMR was similar for both groups with 13—14 years before and 5–7 years after the reference date. The two cohorts were largely similar except that BMI and frequency of healthcare encounters were greater in subjects with diabetes.

Conclusion

The cohort described here will be useful for the examination of the temporal relationship between diabetes and cancer and is unique in that it allows for determination of the date of diabetes onset with reasonable accuracy.

Acute hypophosphatasemia

The temporal evolution of a low serum alkaline phosphatase value may relate to its cause. Precipitous lowering of serum alkaline phosphatase below the lower range of normal is uncommon and may indicate severe physiologic stress and increased short-term mortality.

INTRODUCTION

The differential diagnosis of a low serum alkaline phosphatase (ALP) value (hypophosphatasemia) is wide ranging, anecdotal, and unfamiliar. The temporal evolution of hypophosphatasemia may relate to its cause. The purpose of this study is to report conditions and circumstances associated with precipitous lowering of serum ALP below the lower range of normal.

METHODS

Marshfield Clinic IRB approved use of their electronic medical record to search for subjects with at least two serum ALP values ≤ 40 U/L (normal 40-125 U/L). When the temporal evolution of the qualifying ALP values indicated a precipitous lowering from usually normal serum ALP values, the subject was deemed to have acute hypophosphatasemia. Thirty years of laboratory data and 10 years of clinical narrative were analyzed. Associated diagnoses, clinical circumstances, and short-term mortality were recorded.

RESULTS

A total of 458,767 subjects had 2,584,051 serum ALP values, and 5,190 (1.1 %) subjects had at least two serum values ≤ 40 U/L. A detailed review of 1,276 subjects selected on the basis of their lowest ALP value and age identified 190 subjects with acute hypophosphatasemia. Acute hypophosphatasemia was recorded during periods of major trauma/surgery, multisystem failure, acute anemia, blood product transfusions (often massive), apheresis, hypomagnesemia, and acute caloric restriction. Twenty-eight subjects (15 %) died within 35 days of their nadir serum ALP.

CONCLUSION

Acute hypophosphatasemia is associated with profound illness or physiologic stress and followed by increased short-term mortality. The temporal evolution of hypophosphatasemia may relate to its cause.

24-hour urinary calcium in primary hyperparathyroidism

OBJECTIVE

To establish whether urinary and serum calcium levels are correlated in patients with primary hyperparathyroidism (PHPT) and to evaluate related factors including serum levels of parathyroid hormone (PTH) and vitamin D, age, gender and renal function.

DESIGN

Retrospective review on patients undergoing a parathyroidectomy for PHPT from 2000- 2008. Data collected included: age, sex, preoperative serum calcium (ionized and total), creatinine, PTH, postoperative ionized calcium, vitamin D, and 24-hour urine calcium and creatinine. Data were evaluated by standard descriptive statistics.

RESULTS

Of the 214 patients evaluated, preoperative 24-hour urinary calcium was available for 150 patients (70%). 24-hour urine calcium levels did not correlate significantly with preoperative total serum or ionized calcium, PTH, vitamin D, or postoperative serum ionized calcium. There were significant correlations (P<0.0001) of 24-hour urinary calcium with age, serum creatinine, and urine creatinine. Secondary analysis grouped subjects by urinary calcium level greater or less than 400 mg/24 hours. Age and urinary creatinine were significantly different between the two groups. CONCLUSIONS In patients with PHPT who underwent parathyroidectomy, there was little correlation between preoperative 24-hour urine calcium and preoperative serum calcium, PTH, or vitamin D levels. 24-hour urine calcium levels were correlated with renal function and age, but these correlations are likely to occur in the general population and are not specific to this disease group.

Prostate cancer risk in pre-diabetic men: a matched cohort study

BACKGROUND

Diagnosis and duration of type 2 diabetes mellitus (DM) appear to be associated with decreased prostate cancer risk. Limitations of previous studies include methods of subject selection and accurate definition of DM diagnosis. We examined the temporal relationship between DM and prostate cancer risk exploring the period of greatest risk starting from the prediabetic to the post-diabetic period using clinical and administrative data to accurately define the date of DM diagnosis.

METHODS

We identified 5,813 men who developed DM between January 1, 1995 and December 31, 2009 (reference date, date of DM onset or matched date for non-diabetic cohort) and 28,019 non-diabetic men matched by age, smoking history, residence, and reference date. Prostate cancer incidence before and after the reference date was assessed using Cox regression modeling adjusted for matching variables, body mass index, insurance status, and comorbidities. Primary outcomes included hazard ratio (HR) and number needed to be exposed to DM for one additional person to be harmed (NNEH) or benefit (NNEB) with respect to prostate cancer risk.

RESULTS

After full adjustment, the HR for prostate cancer before DM diagnosis was 0.96 (95% CI 0.85-1.08; P=0.4752), and the NNEB was 974 at DM diagnosis. After the reference date, the fully-adjusted HR for prostate cancer in diabetic men was 0.84 (95% CI 0.72-0.97, P=0.0167), and the NNEB 3 years after DM onset was 425. The NNEB continued to decrease over time, reaching 63 at 15 years after DM onset, suggesting an increasing protective effect of DM on prostate cancer risk over time. No significant difference between the diabetic and non-diabetic cohort was found prior to reference date.

CONCLUSION

Prostate cancer risk is not reduced in pre-diabetic men but decreases after DM diagnosis and the protective effect of DM onset on prostate cancer risk increases with DM duration.

The use of dietary supplements and their association with blood pressure in a large Midwestern cohort

BACKGROUND

There have been numerous studies assessing the association of diet and blood pressure but little is known about the association between less commonly used nutritional supplements and blood pressured. The purpose of this study was to quantify the use of dietary supplements and their potential association with blood pressure in a large population-based cohort of adults in the Midwest.

METHODS

The Personalized Medicine Research Project cohort was the population source for the current study. The current study includes subjects with Dietary History Questionnaire (DHQ) data available as well as at least one clinical blood pressure measurement recorded in their electronic medical record. After excluding extreme outlying measurements, median systolic and diastolic blood pressure measurements were calculated for each individual and were compared for subjects who did and did not report taking one of a list of 37 different supplements listed on the DHQ more than once per week over the previous 12 months.

RESULTS

9,732 subjects had both blood pressure and DHQ data available. They ranged in age from 18 to 98 years (mean 56 years) and 3,625 (37%) were male. Nine of 37 supplements showed evidence for association with blood pressure: coenzyme Q10, fish oil, iron, bilberry, echinacea, evening primrose oil, garlic, goldenseal and milk thistle. With the exception of the mineral iron, mean systolic and diastolic blood pressures were higher for users of the specific supplements than non-users.

CONCLUSIONS

These results should not be interpreted as causal, nor can the direction of the association be assumed to be correct because the temporality of the association is unknown. We hope the observed significant associations will foster future research to evaluate blood pressure effects of dietary supplements.

Characterization of statin dose response in electronic medical records

Efforts to define the genetic architecture underlying variable statin response have met with limited success, possibly because previous studies were limited to effect based on a single dose. We leveraged electronic medical records (EMRs) to extract potency (ED50) and efficacy (Emax) of statin dose-response curves and tested them for association with 144 preselected variants. Two large biobanks were used to construct dose-response curves for 2,026 and 2,252 subjects on simvastatin and atorvastatin, respectively. Atorvastatin was more efficacious, was more potent, and demonstrated less interindividual variability than simvastatin. A pharmacodynamic variant emerging from randomized trials (PRDM16) was associated with Emax for both. For atorvastatin, Emax was 51.7 mg/dl in subjects homozygous for the minor allele vs. 75.0 mg/dl for those homozygous for the major allele. We also identified several loci associated with ED50. The extraction of rigorously defined traits from EMRs for pharmacogenetic studies represents a promising approach to further understand the genetic factors contributing to drug response.

Increased risk of colon cancer in men in the pre-diabetes phase

BACKGROUND

Historically, studies exploring the association between type 2 diabetes mellitus (DM) and cancer lack accurate definition of date of DM onset, limiting temporal analyses. We examined the temporal relationship between colon cancer risk and DM using an electronic algorithm and clinical, administrative, and laboratory data to pinpoint date of DM onset.

METHODS

Subjects diagnosed with DM (N = 11,236) between January 1, 1995 and December 31, 2009 were identified and matched at a 5∶1 ratio with 54 365 non-diabetic subjects by age, gender, smoking history, residence, and diagnosis reference date. Colon cancer incidence relative to the reference date was used to develop Cox regression models adjusted for matching variables, body mass index, insurance status, and comorbidities. Primary outcomes measures included hazard ratio (HR) and number needed to be exposed for one additional person to be harmed (NNEH).

RESULTS

The adjusted HR for colon cancer in men before DM onset was 1.28 (95% CI 1.04-1.58, P = 0.0223) and the NNEH decreased with time, reaching 263 at DM onset. No such difference was observed in women. After DM onset, DM did not appear to alter colon cancer risk in either gender.

CONCLUSIONS

Colon cancer risk is increased in diabetic men, but not women, before DM onset. DM did not alter colon cancer risk in men or women after clinical onset. In pre-diabetic men, colon cancer risk increased as time to DM onset decreased, suggesting that the effects of the pre-diabetes phase on colon cancer risk in men are cumulative.

Does CALU SNP rs1043550 contribute variability to therapeutic warfarin dosing requirements?

OBJECTIVES

Calumenin, a molecular chaperone, exerts a regulatory effect on the vitamin K-dependent γ-carboxylation redox cycle that inhibits transfer of the reduced vitamin K from VKORC1, the pharmacological target of warfarin, to the γ-carboxylase. Because of its polymorphic structure and central role in the warfarin metabolic pathway, a contributory role for calumenin to warfarin dose variability has been posited. The current study sought to validate modulation of therapeutic dosing requirements by a single nucleotide polymorphisms (SNP) occurring in the calumenin gene (CALU) reported in previous studies. The CALU SNP was further modeled to detect interaction with SNPs occurring in VKORC1, CYP2C9, and CYP4F2 genes and characterize any additional contribution to variability in therapeutic warfarin dose requirement.

SETTING

The study was undertaken in an established, well-characterized cohort of subjects treated with warfarin in the Anticoagulation Clinic of Marshfield Clinic in Marshfield, Wisconsin.

METHODS

Subjects (N=491) previously genotyped for SNPS known to contribute variability to therapeutic warfarin dose requirement were genotyped for CALU SNP rs1043550, using TaqMan assays. Contribution of CALU SNP rs1043550 was modeled relative to other genotypic and phenotypic characteristics including gender, diagnosis, age, body surface area, underlying indication for warfarin, comorbidities, and pharmacological exposures. Interaction between SNPs impacting on warfarin dose requirements and calumenin SNPs was also modeled.

RESULTS

Small differences in warfarin dosing requirements detected among individuals encoding the mutant G allele in the calumenin SNP were not statistically or clinically significant relative to therapeutic warfarin dose requirement and did not independently contribute significantly to the warfarin dosing model. Interaction between calumenin and VKORC1 SNPs contributed only minor additional variability to that ascribed to the wild type VKORC1 genotype.

CONCLUSIONS

The impact of the CALU SNP on warfarin dose variability was minor and did not contribute significantly to therapeutic warfarin dose requirement in our study cohort. While no contribution was noted for the SNP examined in the present study, further examination of interaction between genetic elements contributing major impact on therapeutic warfarin dose requirements and genes exhibiting a lesser contribution is warranted.

Validation of electronic medical record-based phenotyping algorithms: results and lessons learned from the eMERGE network

BACKGROUND

Genetic studies require precise phenotype definitions, but electronic medical record (EMR) phenotype data are recorded inconsistently and in a variety of formats.

OBJECTIVE

To present lessons learned about validation of EMR-based phenotypes from the Electronic Medical Records and Genomics (eMERGE) studies.

MATERIALS AND METHODS

The eMERGE network created and validated 13 EMR-derived phenotype algorithms. Network sites are Group Health, Marshfield Clinic, Mayo Clinic, Northwestern University, and Vanderbilt University.

RESULTS

By validating EMR-derived phenotypes we learned that: (1) multisite validation improves phenotype algorithm accuracy; (2) targets for validation should be carefully considered and defined; (3) specifying time frames for review of variables eases validation time and improves accuracy; (4) using repeated measures requires defining the relevant time period and specifying the most meaningful value to be studied; (5) patient movement in and out of the health plan (transience) can result in incomplete or fragmented data; (6) the review scope should be defined carefully; (7) particular care is required in combining EMR and research data; (8) medication data can be assessed using claims, medications dispensed, or medications prescribed; (9) algorithm development and validation work best as an iterative process; and (10) validation by content experts or structured chart review can provide accurate results.

CONCLUSIONS

Despite the diverse structure of the five EMRs of the eMERGE sites, we developed, validated, and successfully deployed 13 electronic phenotype algorithms. Validation is a worthwhile process that not only measures phenotype performance but also strengthens phenotype algorithm definitions and enhances their inter-institutional sharing.

Laboratory evaluation for vitamin B12 deficiency: the case for cascade testing

OBJECTIVE

Potential vitamin B(12) deficiency is a common clinical diagnostic problem, and many providers have a low threshold for initiating therapy. The goal of this study was to systematically evaluate current practice patterns regarding the laboratory evaluation of suspected vitamin B(12) deficiency.

METHODS

This retrospective study reviewed the electronic medical records of 192 patients initiated on intramuscular vitamin B(12) injections.

RESULTS

Only 12 patients had objectively documented hematologic responses: decrease of mean corpuscular volume by ≥5 fL with stable or improved hemoglobin. Another 5 patients had equivocal hematologic responses. There was one plausible neurologic response. Thus, only 18 (9.4%) of 192 patients had data supportive of a clinical response. In these 18 patients, the baseline serum B(12) level was ≤107 pg/mL; only 3 patients also had a baseline serum methylmalonic acid level, which was ≥1.29 μmol/L in all 3 patients.

CONCLUSIONS

Currently, only a small minority of patients initiated on intramuscular vitamin B(12) supplementation derive any meaningful clinical benefit. Furthermore, current testing recommendations for vitamin B(12) deficiency are usually not followed. Up-front ordering of a diagnostic testing cascade is recommended to improve compliance; an example is presented with decision points chosen to improve specificity for clinically evident vitamin B(12) deficiency without loss of sensitivity. Ultimately, a better understanding of vitamin B(12) physiology is needed to develop and evaluate laboratory tests that more accurately reflect true intracellular vitamin B(12) status.

Importance of multi-modal approaches to effectively identify cataract cases from electronic health records

OBJECTIVE

There is increasing interest in using electronic health records (EHRs) to identify subjects for genomic association studies, due in part to the availability of large amounts of clinical data and the expected cost efficiencies of subject identification. We describe the construction and validation of an EHR-based algorithm to identify subjects with age-related cataracts.

MATERIALS AND METHODS

We used a multi-modal strategy consisting of structured database querying, natural language processing on free-text documents, and optical character recognition on scanned clinical images to identify cataract subjects and related cataract attributes. Extensive validation on 3657 subjects compared the multi-modal results to manual chart review. The algorithm was also implemented at participating electronic MEdical Records and GEnomics (eMERGE) institutions.

RESULTS

An EHR-based cataract phenotyping algorithm was successfully developed and validated, resulting in positive predictive values (PPVs) >95%. The multi-modal approach increased the identification of cataract subject attributes by a factor of three compared to single-mode approaches while maintaining high PPV. Components of the cataract algorithm were successfully deployed at three other institutions with similar accuracy.

DISCUSSION

A multi-modal strategy incorporating optical character recognition and natural language processing may increase the number of cases identified while maintaining similar PPVs. Such algorithms, however, require that the needed information be embedded within clinical documents.

CONCLUSION

We have demonstrated that algorithms to identify and characterize cataracts can be developed utilizing data collected via the EHR. These algorithms provide a high level of accuracy even when implemented across multiple EHRs and institutional boundaries.

Determinants of early-stage hearing loss among a cohort of young workers with 16-year follow-up

OBJECTIVES

The authors had a unique opportunity to study the early impacts of occupational and recreational exposures on the development of noise-induced hearing loss (NIHL) in a cohort of 392 young workers. The objectives of this study were to estimate strength of associations between occupational and recreational exposures and occurrence of early-stage NIHL and to determine the extent to which relationships between specific noise exposures and early-stage NIHL were mitigated through the use of hearing protection.

METHODS

Participants were young adults who agreed to participate in a follow-up of a randomised controlled trial. While the follow-up study was designed to observe long-term effects (up to 16 years) of a hearing conservation intervention for high school students, it also provided opportunity to study the potential aetiology of NIHL in this worker cohort. Study data were collected via exposure history questionnaires and clinical audiometric examinations.

RESULTS

Over the 16-year study period, the authors documented changes to hearing acuity that exceeded 15 dB at high frequencies in 42.8% of men and 27.7% of women. Analyses of risk factors for NIHL were limited to men, who comprised 68% of the cohort, and showed that risks increased in association with higher levels of the most common recreational and occupational noise sources, as well as chemical exposures with ototoxic potential. Use of hearing protection and other safety measures, although not universal and sometimes modest, appeared to offer some protection.

CONCLUSIONS

Early-stage NIHL can be detected in young workers by measuring high-frequency changes in hearing acuity. Hearing conservation programmes should focus on a broader range of exposures, whether in occupational or non-occupational settings. Priority exposures include gunshots, chainsaws, power tools, smoking and potentially some chemical exposures.