Discrete-time Survival Analysis Research Articles

Prospective association of tobacco retailer density and neighbourhood walkability with youth vaping initiation in California, USA

BackgroundTobacco retailer density might influence youth e-cigarette use due to increased access and exposure to point-of-sale marketing. There is a need for longitudinal investigations on the association of tobacco retailer...

Discrete-Time Survival Analysis Incorporating Time Structure in Developmental Research

Discrete-time survival analysis (DTSA) is a method widely used by social and behavioral researchers as it aids in the exploration of patterns in time-to-event measures. However, the traditional DTSA models often fail to adequately represent the structured dynamics of hazardous processes. This study introduces structural DTSA, an alternative approach that extends traditional DTSA by incorporating functional forms of hazard changes. With structural DTSA, a reparameterization of the functional forms is also possible for more meaningful interpretations of the results of time-to-event data analyses. This study aims to provide a detailed tutorial on structured DTSA, demonstrating its applicability in social and behavioral research. Henceforth, we demonstrate the application of structured DTSA using data on smoking initiation from the National Longitudinal Study of Youth 1997 (NLSY97). These findings highlight the potential of structured DTSA for various developmental studies.

The Determinants of Recall Event Timing of Contaminated Frozen Poultry Products in Retail Outlets in North-Central Nigeria

This study examined the determinants of the recall event timing of contaminated frozen poultry products in retail outlets in North-Central Nigeria. It specifically identified the potential sources of frozen poultry product hazards in retail outlets, assessed the effectiveness of existing management strategies employed by retailers in preventing frozen poultry product recall in the outlets, and examined the factors influencing the recall event timing of contaminated frozen poultry products in retail outlets in the study area. Multistage sampling was employed to sample 202 respondents, and the data collected using a well-structured questionnaire was analyzed using descriptive statistics and discrete-time survival analysis. The results showed that most of the frozen poultry product retailers in outlets in the study area were men within the age bracket of 21 and 40 years and had a monthly restocking frequency of approximately four times. The result revealed that power outage was the highest potential source of hazards associated with frozen poultry products in retail outlets in the study area. Packaging poultry products before freezing, product labelling, and fridge segmentation are effective management strategies. The result of the factors influencing the recall event timing of contaminated frozen poultry products in retail outlets showed that retailing experience (P<0.01) and cooperative membership (P>0.01) significantly influenced the recall event timing of contaminated frozen poultry products in the study area. The study recommends that the Government offer tax incentives to retailers investing in reliable backup power solutions and provide guidelines for effective communication during recall events.

Health System Expansion and Changes in Medicare Beneficiary Utilization of Safety Net Providers.

Evidence is limited on insured patients' use of safety net providers as vertically integrated health systems spread throughout the United States. To examine whether market-level health system penetration is associated with: (1) switches in Medicare beneficiaries' usual source of primary care from federally qualified health centers (FQHCs) to health systems; and (2) FQHCs' overall Medicare patient and visit volume. Beneficiary-level discrete-time survival analysis and market-level linear regression analysis using Medicare fee-for-service claims data from 2013 to 2018. A total of 659,652 Medicare fee-for-service beneficiaries aged 65 and older lived in one of 27,386 empirically derived primary care markets whose usual source of care in 2013 was an FQHC or a non-FQHC-independent physician organization that predominantly served low-income patients. Beneficiary-year measure of the probability of switching to health system-affiliated physician organizations and market-year measures of the number of FQHC visits by Medicare beneficiaries, number of beneficiaries attributed to FQHCs, and FQHC Medicare market shares. During 2013-2018, 16.5% of beneficiaries who sought care from FQHCs switched to health systems. When health system penetration increases from the 25th to 75th percentile, the probability of Medicare FQHC patient switching increases by 4.6 percentage points, with 22 fewer Medicare FQHC visits and 4 fewer beneficiaries attributed to FQHCs per market year. Complex patients and patients who sought care from non-FQHC, independent physician organizations exhibited higher rates of switching to health systems. Health system expansion was associated with the loss of Medicare patients by FQHCs, suggesting potential negative spillovers of vertical integration on independent safety net providers.

Student attrition in gender-atypical fields of study: a case of disapproval by parents and friends or lacking social integration?

AbstractIn most industrialized countries, the choice of college majors is segregated by gender. Few students enroll in gender-atypical majors. Previous studies suggested that some attrition risks are associated with the gender composition of majors. In this paper, I investigated whether students in gender-atypical majors are more likely to leave the major by dropping out or switching to a different major with more same-sex students than those majoring in gender-typical subjects. Furthermore, I hypothesized that the relation between gender composition and non-completion risks is partially mediated by two social processes, namely poor social integration and disapproval of the major from parents and friends. Using data from undergraduate students from the German National Educational Panel Study, I conducted discrete-time survival analyses and a KHB decomposition. I found that both men and women in gender-atypical majors have a higher risk of switching to a major with a higher percentage of same-sex students than students in gender-typical majors. Women in gender-atypical majors also have a higher dropout risk. Poor social integration and disapproval of the major by parents and friends increase the switching risk and, in the case of social integration, also the dropout risk for all students. However, these two aspects cannot explain the higher attrition risk for students in gender-atypical majors, with one exception. Only for women in gender-atypical majors, lower approval of the major by friends partly mediates the association between the gender composition of the major and the risk of switching to a more female-dominated major.

State firearm legislation and initiation of gun carrying in the USA

ObjectiveEarly onset of gun carrying correlates with a heightened risk of violent offences and injuries. This research estimates the association between state firearm legislation and first-time handgun carrying in the...

Association between albuminuria and glomerular filtration rate with incident frailty

IntroductionThe association between estimated glomerular filtration rate (eGFR) and albuminuria with incident frailty in generally healthy older individuals is unclear. We investigated whether baseline eGFR or urine albumin-to-creatinine ratio (UACR) are associated with incident frailty assessed using two separate methods: a modified Fried frailty phenotype (FP), and a deficit accumulation frailty index (FI). MethodsThis was a secondary analysis of the ASPirin in Reducing Events in the Elderly (ASPREE) randomised trial cohort, which enrolled independent, well, older adults aged ≥65 years in Australia and the United States. Time to incident frailty was analysed using discrete time survival analysis. ResultsIn total, 16,965 participants were included using the FP, mean age was 75.0 ± 4.5 years, median baseline eGFR was 78.6 mL/min/1.73m2 (IQR 67.6, 89.5), and the median UACR was 0.80 mg/mmol (0.50, 1.50). Data to generate the FI outcomes was available for 12,272 participants. The relationships between eGFR and both incident FP and FI were non-linear, such that an eGFR <30 or ≥95 mL/min/1.73m2 was significantly associated with an increased risk of incident frailty. For every doubling of baseline UACR, risk of incident frailty increased by 4% using the FP (HR: 1.04, 95% CI: 1.02, 1.07) and the FI (HR: 1.04, 95% CI: 1.01, 1.07). ConclusionIn older, generally healthy adults, both low and high eGFRs were associated with increased risk of incident frailty. Doubling of UACR, even at low levels, was independently associated with incident frailty.

The Association Between Accelerated Biological Aging and Cardiovascular Outcomes in Older Adults with Hypertension

BackgroundCurrent hypertension treatments rely on chronological age, which may not reflect individual differences in aging and its impact on cardiovascular health. This study aimed to determine whether biological age can predict adverse outcomes in older adults with hypertension, independent of traditional risk factors including chronological age. MethodsAn analysis of a prospective cohort was conducted using data from the Health and Retirement Study, a longitudinal survey of older adults in the United States. The Klemera-Doubal method was employed to calculate the biological age of the participants with hypertension at the time of enrollment in 2016. Discrete-time survival analysis was conducted to analyze the relationship between accelerated biological aging and the risk of mortality, heart disease, and stroke over four years of follow-up. ResultsA total of 4,442 individuals were analyzed. Of these, 2,438 showed decelerated aging, whereas 2,004 experienced accelerated aging (biological age > chronological age). The median age of the patients in both groups was around 70 years. Both groups had similar racial and ethnic distributions and predominantly consisted of non-Hispanic whites. The accelerated aging group had a higher prevalence of chronic diseases, lower education levels, and less wealth than the decelerated aging group. After adjustment for these differences, accelerated aging was associated with a higher risk of a composite outcome of death, heart disease, and stroke, with an adjusted hazard ratio (a-HR) of 1.62 (95% confidence interval: 1.27-2.06, p= 0.001). ConclusionsAccelerated biological age is a predictor of cardiovascular outcomes and death in patients with hypertension.

Characteristics of attrition within the SuperMIX cohort of people who inject drugs: a multiple event discrete-time survival analysis

BackgroundCompared to the general population, people who inject drugs have poor health and wellbeing. Longitudinal studies can provide insight into factors driving these worse health outcomes but are subject to methodological challenges, such as cohort attrition. The aim of this study was to assess and characterise attrition in a prospective cohort of people who inject drugs in Victoria, Australia.MethodsUsing annually collected self-reported data from The Melbourne Injecting Drug User Cohort Study (SuperMIX) from September 2008 to January 2021, we estimated the incidence of participants being lost-to-follow-up (LTFU), with an episode of being LTFU defined as participants not undertaking a follow-up interview within two years of their last interview. We utilised a multiple event discrete-time survival analysis on participant period-observation data to estimate the associations between key factors and LTFU. Key areas of exposure measurement in analyses were sociodemographic, drug use and mental health.ResultsA total of n = 1328 SuperMIX participants completed a baseline interview, with n = 489 (36.8%) LTFU, i.e. not completing a follow-up interview in the following two years. Increased attrition was observed among SuperMIX participants who were: born outside Australia, younger than 30 years, reporting having completed fewer years of education, not residing in stable accommodation, not in stable employment and not on opioid agonist therapy (OAT).ConclusionsThe attrition rate of the SuperMIX cohort has largely been stable throughout the duration of the study. Higher attrition rates among individuals at greater sociodemographic disadvantage and not on OAT suggest that additional efforts are required to retain these participants. Findings also suggest that SuperMIX might not be capturing data on adverse health and wellbeing outcomes among subpopulations at high risk of harm.

BMI Trajectories and the Influence of Missing Data

Abstract Introduction Body Mass Index (BMI) trajectories have been estimated in various ways. These estimates are important to understand how BMI develops over time and for use in cost-effectiveness analysis. However, missing data is often stated as a limitation in studies that analyse BMI over time and there is little research into how missing data can influence these BMI trajectories. The aim of this study is to determine how much influence missing data can have when estimating BMI trajectories and to explore the effects this has on subsequent analysis. Methods This study uses data from the English Longitudinal Study of Aging. First, a growth mixture model is used to estimate distinct BMI trajectories in adults over the age of 50. Next, methods that assume data is missing at random (MAR) are used: complete case analysis and multiple imputation. Finally, Diggle Kenward and Roy methods that assume data is missing not at random (MNAR) are implemented. Estimated trajectories from each method are then used to predict the risk of developing type 2 diabetes (T2DM) using discrete-time survival analysis. Results Four distinct trajectories are identified using each of the methods to account for missing data: stable overweight, elevated BMI, increasing BMI, and decreasing BMI. However, the likelihoods of individuals following the different trajectories differs between the different methods. Results show that the influence of BMI trajectory on T2DM is reduced after accounting for missing data. More work is needed to understand which methods for missing data are most appropriate and give the most reliable results. Conclusions Missing data can significantly influence estimations of BMI trajectories. When using BMI trajectories to inform cost-effectiveness analysis or policymaking, missing data should be considered. More research is needed to examine the extent to which accounting for missing data might influence the cost-effectiveness of policies, e.g. weight management interventions. Key messages • Missing data is important when modelling BMI trajectories. • More research is needed to examine the extent to which accounting for missing data might influence the cost-effectiveness of policies, e.g. weight management interventions.

Undetected suicide attempts among U.S. soldiers: results from the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS).

While previous studies have reported high rates of documented suicide attempts (SAs) in the U.S. Army, the extent to which soldiers make SAs that are not identified in the healthcare system is unknown. Understanding undetected suicidal behavior is important in broadening prevention and intervention efforts. Representative survey of U.S. Regular Army enlisted soldiers (n = 24 475). Reported SAs during service were compared with SAs documented in administrative medical records. Logistic regression analyses examined sociodemographic characteristics differentiating soldiers with an undetected SA v. documented SA. Among those with an undetected SA, chi-square tests examined characteristics associated with receiving a mental health diagnosis (MH-Dx) prior to SA. Discrete-time survival analysis estimated risk of undetected SA by time in service. Prevalence of undetected SA (unweighted n = 259) was 1.3%. Annual incidence was 255.6 per 100 000 soldiers, suggesting one in three SAs are undetected. In multivariable analysis, rank ⩾E5 (OR = 3.1[95%CI 1.6-5.7]) was associated with increased odds of undetected v. documented SA. Females were more likely to have a MH-Dx prior to their undetected SA (Rao-Scott χ21 = 6.1, p = .01). Over one-fifth of undetected SAs resulted in at least moderate injury. Risk of undetected SA was greater during the first four years of service. Findings suggest that substantially more soldiers make SAs than indicated by estimates based on documented attempts. A sizable minority of undetected SAs result in significant injury. Soldiers reporting an undetected SA tend to be higher ranking than those with documented SAs. Undetected SAs require additional approaches to identifying individuals at risk.

Gestational urinary concentrations of glyphosate and aminomethylphosphonic acid in relation to preterm birth: the MIREC study.

Few high-quality studies have evaluated associations between urinary glyphosate or its environmental degradate (aminomethylphosphonic acid (AMPA)] and preterm birth (PTB). To quantify associations between urinary glyphosate and AMPA and preterm birth in the pan-Canadian Maternal-Infant Research on Environmental Chemicals (MIREC) study and determine if associations differ by fetal sex. We measured first trimester urinary glyphosate and AMPA concentrations in MIREC participants who were recruited between 2008-2011 from 10 Canadian cities. Of the 1880 participants whose first trimester urine samples were analyzed for glyphosate or AMPA, 1765 delivered a singleton, live birth. Our primary outcome was preterm birth (PTB) defined as births occurring between 20 and <37 weeks. Secondary outcomes were spontaneous preterm births (sPTB) and gestational age. We modelled the hazard of PTB and sPTB using discrete time survival analysis with multivariable logistic regression to calculate odds ratios (OR). We used multivariable linear regression models to quantify associations between analytes and gestational age. To assess effect modification by fetal sex, we stratified all models and calculated interaction terms. In the logistic regressions models we additionally calculated the relative excess risk due to interaction. Six percent (n = 106) of the study population delivered preterm, and 4.7% (n = 83) had a spontaneous preterm birth. Median specific-gravity standardized concentrations of glyphosate and AMPA were 0.25 and 0.21 µg/L. Associations between both glyphosate or AMPA and PTB, sPTB, and gestational age centered around the null value. The adjusted ORs of PTB for each doubling of glyphosate and AMPA concentrations were 0.98 (95% CI: 0.94, 1.03) and 0.99 (95% CI: 0.92, 1.06) respectively. We observed no evidence of differences by fetal sex. In this Canadian pregnancy cohort, neither glyphosate nor AMPA urinary concentrations was associated with PTB or reduced gestational length.

Predictors of Cigar, Cigarillo, and Little Cigar Initiation Among Hip Hop-Identifying Youth

Background: We explored predictors of cigar product initiation among Hip Hop-identifying U.S. youth using data from the U.S. Food and Drug Administration’s Fresh Empire evaluation. Participants were Hip Hop-identifying youth living in evaluation markets who had not initiated cigar product use at their first survey. Objectives: We modeled cigar product initiation odds using discrete time survival analysis logistic regression models as a function of factors related to one’s large social, physical, social/normative, and intrapersonal environment, and other tobacco use. Results: In the unique sample, 26.2% initiated cigar product use. Factors associated with higher cigar product initiation odds included: current/former (vs. non-susceptible never) cigarette smoking (odds ratio [OR]=5.35; p=.008); cigarette experimentation (vs. non-susceptible never smoking) (OR=3.26; p<.001); current (vs. never) e-cigarette use (OR=2.06; p<.001) and hookah use (OR=1.83; p=.011); having at least one friend who uses marijuana (OR=1.43; p=.008); high music use (OR=1.32; p=.035); household tobacco use (OR=1.26; p =.042); increased age (OR=1.18; p< .001); and higher sensation seeking (OR=1.16; p=.018). Youth reporting higher perceived smoking risks had lower cigar product initiation odds (OR=0.86; p=.029) as did Hispanic (OR=0.53; p<.001) and non-Hispanic Other youth (OR= 0.68; p=.023) (vs. non-Hispanic Black youth). Conclusions: The finding that high music use predicted cigar product initiation should be considered in light of cigar brand sponsorship of musical artists and events and indicates a potential opportunity for counter messaging. Peer crowd segmentation in this study identified unique and differing factors that influence tobacco use risk among Hip Hop-identifying youth that are not found in the general population.

Antipsychotic Discontinuation and New Trazodone Use in Ontario Nursing Homes: Evidence of Medication Substitution

ObjectivesAn unintended consequence of efforts to reduce antipsychotic medications in nursing homes is the increase in use of other psychotropic medications; however, evidence of substitution remains limited. Our objective was to measure individual-level prescribing patterns consistent with substitution of trazodone for antipsychotics. DesignRetrospective cohort study. Setting and ParticipantsResidents of Ontario nursing homes aged 66–105 years with an admission assessment between April 1, 2010, and March 31, 2019, who were receiving an antipsychotic and had no antidepressant medication use at admission to the nursing home. MethodsWe used linked health administrative data to examine changes in medication use over three quarterly assessments following admission. Antipsychotic and trazodone use were measured at each assessment. The rate of trazodone initiation was compared between residents no longer dispensed an antipsychotic (discontinued) and those with an ongoing antipsychotic (continued) using discrete time survival analysis, controlling for baseline resident characteristics. ResultsWe identified 13,306 residents dispensed an antipsychotic with no antidepressant use at admission (mean age 84 years, 61.5% women, 82.8% with dementia). As of the first quarterly assessment, nearly 20% of residents no longer received an antipsychotic and 9% received a new trazodone medication. Over time, residents who discontinued antipsychotics had a rate of trazodone initiation that was 82% higher compared to residents who continued (adjusted hazard ratio 1.82, 95% CI 1.66–2.00). Conclusions and ImplicationsResidents admitted to a nursing home with antipsychotic use had a higher rate of trazodone initiation if they discontinued (vs continued) an antipsychotic. These findings suggest antipsychotic substitution with trazodone after entering a nursing home.

Patients May Return to Work Sooner After Laminoplasty: Occupational Outcomes of the Cervical Spondylotic Myelopathy Surgical Trial.

Return-to-work (RTW) is an important outcome for employed patients considering surgery for cervical spondylotic myelopathy (CSM). We conducted a post hoc analysis of patients as-treated in the Cervical Spondylotic Myelopathy Surgical Trial, a prospective, randomized trial comparing surgical approaches for CSM to evaluate factors associated with RTW. In the trial, patients were randomized (2:3) to either anterior surgery (anterior cervical decompression/fusion [ACDF]) or posterior surgery (laminoplasty [LP], or posterior cervical decompression/fusion [PCDF], at surgeon's discretion). Work status was recorded at 1, 3, 6, and 12 months postoperatively. For patients working full-time or part-time on enrollment, time to RTW was compared across as-treated surgical groups using discrete-time survival analysis. Multivariate logistic regression was used to assess predictors of RTW. Clinical outcomes were compared using a linear mixed-effects model. A total of 68 (42%) of 163 patients were working preoperatively and were analyzed. In total, 27 patients underwent ACDF, 29 underwent PCDF, and 12 underwent LP. 45 (66%) of 68 patients returned to work by 12 months. Median time to RTW differed by surgical approach (LP = 1 month, ACDF = 3 months, PCDF = 6 months; P = .02). Patients with longer length-of-stay were less likely to be working at 1 month (odds ratio 0.51; 95% CI, 0.29-0.91; P = .022) and 3 months (odds ratio 0.39; 95% CI, 0.16-0.96; P = .04). At 3 months, PCDF was associated with lower Short-Form 36 physical component summary scores than ACDF (estimated mean difference [EMD]: 6.42; 95% CI, 1.4-11.4; P = .007) and LP (EMD: 7.98; 95% CI, 2.7-13.3; P = .003), and higher Neck Disability Index scores than ACDF (EMD: 12.48; 95% CI, 2.3-22.7; P = .01) and LP (EMD: 15.22; 95% CI, 2.3-28.1; P = .014), indicating worse perceived physical functioning and greater disability, respectively. Most employed patients returned to work within 1 year. LP patients resumed employment earliest, while PCDF patients returned to work latest, with greater disability at follow-up, suggesting that choice of surgical intervention may influence occupational outcomes.

Factors associated with PrEP-era HIV seroconversion in a 4-year U.S. national cohort of n = 6059 sexual and gender minority individuals who have sex with men, 2017-2022.

Community-based cohort studies of HIV seroconversion can identify important avenues for enhancing HIV prevention efforts in the era of pre-exposure prophylaxis (PrEP). Within individuals, one can assess exposure and outcome variables repeatedly and with increased certainty regarding temporal ordering. This cohort study examined the association of several risk factors with subsequent HIV seroconversion. We report data from a 4-year study (2017-2022) of 6059 HIV seronegative sexual and gender minority individuals who have sex with men who had indications for-, but were not using-, PrEP at enrolment. Participants completed repeat exposure assessments and self-collection of biospecimens for HIV testing. We examined the roles of race and ethnicity, socio-economic status, methamphetamine use and PrEP uptake over the course of follow-up in relation to HIV seroconversion. Over 4 years, 303 of the participants seroconverted across 18,421 person-years (incidence rate = 1.64 [95% CI: 1.59-1.70] per 100 person-years). In multivariable discrete-time survival analysis, factors independently associated with elevated HIV seroconversion risk included being Black/African American (adjusted risk ratio [aRR]: 2.44, 1.79-3.28), Hispanic/Latinx (1.53, 1.19-1.96), housing instability (1.58, 1.22-2.05) and past year methamphetamine use (3.82, 2.74-5.33). Conversely, time since study enrolment (24 vs. 12 months, 0.67, 0.51-0.87; 36 months, 0.60, 0.45-0.80; 48 months, 0.48, 0.35-0.66) and higher education (master's degree or higher vs. less than or equal to high school, 0.36, 0.17-0.66) were associated with reduced seroconversion risk. Compared to non-PrEP users in the past 2 years without a current clinical indication, those who started PrEP but then discontinued had higher seroconversion risk, irrespective of clinical indication (3.23, 1.74-6.46) or lack thereof (4.30, 1.85-9.88). However, those who initiated PrEP in the past year (0.14, 0.04-0.39) or persistently used PrEP in the past 2 years (0.33, 0.14-0.74) had a lower risk of seroconversion. Of all HIV seroconversions observed during follow-up assessments (12, 24, 36 and 48 months), methamphetamine was reported in the 12 months prior 128 (42.2%) times (overall). Interventions that acknowledge race and ethnicity, economic variables such as education and housing instability, and methamphetamine use are critically needed. Not only are interventions to engage individuals in PrEP care needed, but those that retain them, and re-engage those who may fall out of care are essential, given the exceptionally high risk of seroconversion in these groups.

Estimating Gender Differences in the Association between Cognitive Resilience and Mild Cognitive Impairment Incidence

Introduction: Recent evidence suggests that the influence of verbal intelligence and education on the onset of subjective cognitive decline may be modulated by gender, where education contributes less to cognitive resilience (CR) in women than in men. This study aimed to examine gender differences in the association between CR and mild cognitive impairment (MCI) incidence in an Australian population-based cohort. Methods: We included 1,806 participants who had completed at least the first two waves and up to four waves of assessments in the Personality and Total Health (PATH) Through Life study (baseline: 49% female, male = 62.5, SD = 1.5, age range = 60–66 years). CR proxies included measures of educational attainment, occupation skill, verbal intelligence, and leisure activity. Discrete-time survival analyses were conducted to examine gender differences in the association between CR proxies and MCI risk, adjusting for age and apolipoprotein E4 status. Results: Gender differences were only found in the association between occupation and MCI risk, where lower occupation skill was more strongly associated with higher risk in men than in women (odds ratio [OR] = 1.30, 95% confidence interval [CI] [1.07, 1.57]). In both genders, after adjusting for education and occupation, one SD increase in leisure activity was associated with lower MCI risk by 32% (OR = 0.76, 95% CI [0.65, 0.89]). Higher scores in verbal intelligence assessment were associated with reduced risk of MCI by 28% (OR = 0.78, 95% CI [0.69, 0.89]). Conclusion: Occupational experience may contribute to CR differently between genders. Life course cognitive engagement and verbal intelligence may be more protective against MCI than education and occupation for both men and women.

Climate Change and Child Marriage: Evidence from Bangladesh

This paper examines the effects of environmental vulnerability on the risk of child marriage in Bangladesh. Community vulnerability measures are constructed for 240 rural communities in eight districts according to the presence of three indicators of environmental vulnerability—history of cyclones, flooding, and waterlogging. Community data are linked to individual-level adolescent survey data from a representative sample of 15,000 adolescent girls in those communities. Types of environmental vulnerability and the effect on adolescent girls’ marriage outcomes have been explored using discrete time survival analysis. Results show that coastal communities with prolonged waterlogging and salinity have significantly higher child marriage rates, and there is no evidence of higher risks of child marriage in flood-affected areas. The paper concludes that slow and rapid onset events vary in their impact on child marriage. It is important to distinguish between rapid onset factors, such as floods and cyclones, and slow and less dramatically visible factors, such as waterlogging, that affect marriage through longer-term impacts on lives and livelihoods. Programs need to cast a wider net to safeguard girls living in the communities not only where immediate and sudden environmental emergencies have occurred but also in the areas where climate-induced disasters may not seem very visible but have slow, cascading effects and pose a risk for child marriage.

Predicting the onset of myopia in children by age, sex, and ethnicity: Results from the CLEERE Study.

Clinicians and researchers would benefit from being able to predict the onset of myopia for an individual child. This report provides a model for calculating the probability of myopia onset, year-by-year and cumulatively, based on results from the largest, most ethnically diverse study of myopia onset in the United States. This study aimed to model the probability of the onset of myopia in previously nonmyopic school-aged children. Children aged 6 years to less than 14 years of age at baseline participating in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study who were nonmyopic and less hyperopic than +3.00 D (spherical equivalent) were followed up for 1 to 7 years through eighth grade. Annual measurements included cycloplegic autorefraction, keratometry, ultrasound axial dimensions, and parental report of children's near work and time spent in outdoor and/or sports activities. The onset of myopia was defined as the first visit with at least -0.75 D of myopia in each principal meridian. The predictive model was built using discrete time survival analysis and evaluated with C statistics. The model of the probability of the onset of myopia included cycloplegic spherical equivalent refractive error, the horizontal/vertical component of astigmatism (J0), age, sex, and race/ethnicity. Onset of myopia was more likely with lower amounts of hyperopia and less positive/more negative values of J0. Younger Asian American females had the highest eventual probability of onset, whereas older White males had the lowest. Model performance increased with older baseline age, with C statistics ranging from 0.83 at 6 years of age to 0.92 at 13 years. The probability of the onset of myopia can be estimated for children in the major racial/ethnic groups within the United States on a year-by-year and cumulative basis up to age 14 years based on a simple set of refractive error and demographic variables.

Reviving Decades-Old Wisdom: Longitudinal Analysis of Renin-Angiotensin System Inhibitors and Its Effects on Acute Ischemic Stroke to Improve Outcomes.

While renin-angiotensin system (RAS) inhibitors have a longstanding history in blood pressure control, their suitability as first-line in-patient treatment may be limited due to prolonged half-life and kidney failure concerns. Using a cohort design, we assessed the impact of RAS inhibitors, either alone or in combination with beta-blockers, on mortality, while exploring interactions, including those related to end-stage renal disease and serum creatinine levels. Eligible subjects were Acute Ischemic Stroke (AIS) patients aged 18 or older with specific subtypes who received in-patient antihypertensive treatment. The primary outcome was mortality rates. Statistical analyses included cross-sectional and longitudinal approaches, employing generalized linear models, G-computation, and discrete-time survival analysis over a 20-day follow-up period. In our study of 3,058 AIS patients, those using RAS inhibitors had significantly lower in-hospital mortality (2.2%) compared to non-users (12.1%), resulting in a relative risk (RR) of 0.18 (95% CI: 0.12-0.26). Further analysis using G-computation revealed a marked reduction in mortality risk associated with RAS inhibitors (0.0281 vs. 0.0913, risk difference [RD] of 6.31% or 0.0631, 95% CI: 0.046-0.079). Subgroup analysis demonstrated notable benefits, with individuals having creatinine levels below and above 1.3 mg/dl exhibiting statistically significant RD (RD -0.0510 vs. -0.0895), and a significant difference in paired comparison (-0.0385 or 3.85%, CI 0.023-0.054). Additionally, longitudinal analysis confirmed a consistent daily reduction of 0.93% in mortality risk associated with the intake of RAS inhibitors. RAS inhibitors are associated with a significant reduction in in-hospital mortality in AIS patients, suggesting potential clinical benefits in improving patient outcomes.