Nevin Manimala

JAMA Netw Open. 2026 Jan 2;9(1):e2550664. doi: 10.1001/jamanetworkopen.2025.50664.

ABSTRACT

IMPORTANCE: There are well-documented racial and ethnic disparities in preterm birth in the US. The role of household income in temporal preterm birth trends remains largely unexplored.

OBJECTIVE: To examine US preterm birth trends by household income from 2011 to 2021, as well as associations between income and preterm birth according to race and ethnicity.

DESIGN, SETTING, AND PARTICIPANTS: This US population-based, cross-sectional study used data on 411 469 mothers of infants aged 2 to 4 months from the nationally representative Pregnancy Risk Assessment Monitoring System database from 2011 to 2021. Data were analyzed from January to April 2024.

EXPOSURES: Mothers reported annual household income, which was categorized as less than 100% of the federal poverty level (FPL), 100% to 199% of the FPL, and 200% or more of the FPL based on year, state, and household size.

MAIN OUTCOME AND MEASURES: The main outcome was preterm birth, defined as birth at less than 37 weeks’ gestation. Maternal self-reported race and ethnicity was defined as American Indian or Alaska Native, Asian, Hispanic (any race), non-Hispanic Black, non-Hispanic White, and other or multiracial. Trends in preterm birth by income categories were examined, and modified Poisson regression models were built to (1) examine the association between income and preterm birth, (2) adjust for sociodemographic and pregnancy-related covariates, (3) adjust additionally for race and ethnicity, and (4) introduce an interaction between race and ethnicity and income.

RESULTS: Among 411 469 (weighted 20 million) mother-infant dyads (0.8% American Indian or Alaska Native, 5.5% Asian, 15.5% Hispanic, 14.1% non-Hispanic Black, 58.9% non-Hispanic White, and 3.1% other or multiracial), rates of preterm birth increased significantly over time in the groups reporting an annual household income of less than 100% of the FPL (2011, 9.7%; 2021, 11.1%) and 100% to 199% of the FPL (2011, 7.8%; 2021, 10.0%). The preterm birth rate was highest among households reporting household income less than 100% of the FPL within all racial and ethnic groups except Asian. Non-Hispanic Black mothers had the highest rates of preterm birth across all income categories. The association of income with preterm birth remained significant after adjusting for covariates but attenuated to the null after including race and ethnicity in the model. In the lowest income group, non-Hispanic Black mothers had a 19% greater risk of preterm birth compared with non-Hispanic White mothers (adjusted relative risk [ARR], 1.19; 95% CI, 1.11-1.27), whereas in the highest income group, non-Hispanic Black mothers had a 13% greater risk of preterm birth compared with non-Hispanic White mothers (ARR, 1.13; 95% CI, 1.01-1.26).

CONCLUSIONS: In this population-based cross-sectional study, household income disparities in preterm birth widened over time. Black race moderated the association between income and preterm birth, underscoring the need to examine the role of racism in preterm birth disparities.

PMID:41481292 | DOI:10.1001/jamanetworkopen.2025.50664

JAMA Netw Open. 2026 Jan 2;9(1):e2551814. doi: 10.1001/jamanetworkopen.2025.51814.

ABSTRACT

IMPORTANCE: A total of 1723 measles cases have been reported as of November 12, 2025, in the US, reaching their highest levels since elimination in 2000. MMR (measles, mumps, and rubella) vaccination coverage has decreased, and factors associated with delayed and missed vaccination since the COVID-19 pandemic are not well explored.

OBJECTIVES: To characterize coverage and trends of timely MMR vaccination and assess factors associated with late vaccination and nonvaccination by 2 years of age.

DESIGN, SETTING, AND PARTICIPANTS: In this cohort study, infants who accessed routine care within the first 2 months, first year, and second year of life were followed up for 24 months to assess vaccination outcomes between January 1, 2018, and April 30, 2025. Participants were children seeking care within Truveta Data, an electronic health record database from a collective of US health care systems.

EXPOSURES: Timely receipt of routine 2- and 4-month immunizations and adherence to the American Academy of Pediatrics well child visit schedule.

MAIN OUTCOMES AND MEASURES: The primary outcome was timely, late, or no receipt of MMR by 2 years of age. Associations with primary exposures and sociodemographic factors were modeled using mixed-effect logistic regression with state-level random effects. Models were stratified by pre- vs post-COVID-19 MMR eligibility, with results after the COVID-19 pandemic reported as primary.

RESULTS: In this study of 321 743 children (166 017 boys [51.6%]) with regular access to care, 78.4% (252 250 of 321 743) received their first MMR vaccination on time, increasing from 75.6% (12 840 of 16 978) in 2018 to 79.9% (39 739 of 49 767) in 2021, then decreasing to 76.9% (40 306 of 52 388) in 2024. The strongest factors associated with no MMR vaccination by 2 years was late administration of a child’s 2-month vaccines (adjusted odds ratio [AOR], 6.96 [95% CI, 6.60-7.34]) and 4-month vaccines (AOR, 6.16 [95% CI, 5.84-6.50]).

CONCLUSIONS AND RELEVANCE: In this cohort study of children with regular access to care, most received their MMR vaccine on time, but the proportion not receiving the MMR vaccine by 2 years of age has increased since the COVID-19 pandemic. Children who did not receive their 2- and 4-month vaccines on time were significantly more likely to not receive any MMR vaccine by 2 years, highlighting opportunities for intervention.

PMID:41481291 | DOI:10.1001/jamanetworkopen.2025.51814

JAMA Netw Open. 2026 Jan 2;9(1):e2551878. doi: 10.1001/jamanetworkopen.2025.51878.

ABSTRACT

IMPORTANCE: Stress and its psychiatric consequences-including depression, anxiety, and posttraumatic stress disorder (PTSD)-are pertinent to women’s cardiovascular health, but research on intersections with relevant sex-specific factors (eg, hormonal contraceptives) is lacking.

OBJECTIVE: To examine whether stress-related psychiatric diagnoses moderate associations between hormonal contraceptive use and cardiovascular and thrombotic risk.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study included electronic health record data collected from a US hospital-based biobank and analyzed from May 2, 2024, to November 3, 2025. Participants were women aged 18 to 55 years who consented into the biobank before or on September 12, 2020.

EXPOSURES: Lifetime history of stress-related psychiatric disorders, including depression (major depressive disorder), anxiety (generalized anxiety disorder, social anxiety disorder, or panic disorder), and PTSD, defined by International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) codes and analyzed as separate diagnoses, and lifetime history of combined hormonal contraceptive use, defined by RxNorm codes.

MAIN OUTCOMES AND MEASURES: The primary outcomes were major adverse cardiovascular events (MACE; defined as ICD-10 codes for infarction, unstable angina, heart failure, coronary revascularization, peripheral vascular disease, peripheral revascularization, stroke, and/or transient ischemic attack) and deep-vein thrombosis (DVT). Three 2-step hierarchical logistic regressions per outcome were conducted.

RESULTS: In this sample of 31 824 women (mean [SD] age, 38.5 [10.6] years), over one-third (11 950 women [37.6%]) had hormonal contraceptive use history, and stress-related disorders were common (depression, 9116 women [28.5%]; anxiety, 3533 women [11.1%]; PTSD, 1992 women [6.3%]). Associations were mixed across the stress-related disorders, in that depression and anxiety did not moderate associations between contraceptive use and MACE or DVT. In contrast, PTSD modified the association between contraceptive use and MACE but not that between contraceptive use and DVT. Analyses stratified by PTSD status found that only women without PTSD using contraceptives had lower odds for MACE (odds ratio, 0.69; 95% CI, 0.87-3.24). The odds ratio for MACE among women with PTSD was greater than 1, but the finding was not statistically significant (odds ratio, 1.68; 95% CI, 0.87-3.24).

CONCLUSIONS AND RELEVANCE: In this retrospective cohort study, combined hormonal contraceptive use was associated with lower cardiovascular risk in women regardless of depression or anxiety. These protective associations did not extend to women with PTSD, suggesting that there are unique cardiovascular processes in the context of this stress-related disorder and hormonal contraceptive use that warrant further research.

PMID:41481290 | DOI:10.1001/jamanetworkopen.2025.51878

Expert Rev Respir Med. 2026 Jan 2. doi: 10.1080/17476348.2026.2612785. Online ahead of print.

ABSTRACT

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) significantly increases lung cancer risk, with cumulative incidence exceeding 50% at 10 years. We evaluated whether antifibrotic therapies provide cancer-protective effects beyond their established antifibrotic actions.

METHODS: We conducted a systematic review searching MEDLINE, EMBASE, and Cochrane databases through July 2025 per PRISMA guidelines. Observational studies comparing lung cancer incidence in IPF patients receiving antifibrotics (pirfenidone or nintedanib) versus untreated controls were included. Random-effects meta-analysis with sequential sensitivity analyses was performed.

RESULTS: Four observational studies with 15,582 participants were included. Primary pooled risk ratio was 0.39 (95% CI: 0.13-1.14; I² = 98%). Sequential sensitivity analyses addressing confounding by indication and biological heterogeneity demonstrated statistically significant risk reductions: 73% (RR 0.27; 95% CI: 0.16-0.48; I² = 44%) and 76% (RR 0.24; 95% CI: 0.08-0.69; I² = 67%) in pirfenidone-specific analyses.

CONCLUSIONS: Pirfenidone specifically may reduce lung cancer risk in IPF patients by 73-76%, though evidence is limited by observational designs, geographic restriction to East Asian populations, and biological heterogeneity between mechanistically distinct antifibrotic agents. Insufficient data exist for nintedanib. Agent-specific prospective randomized controlled trials are warranted.Protocol registration: PROSPERO identifier CRD420251119104.

PMID:41481252 | DOI:10.1080/17476348.2026.2612785

Int J Epidemiol. 2026 Jan 2;55(1):dyaf214. doi: 10.1093/ije/dyaf214.

ABSTRACT

INTRODUCTION: In air-pollution epidemiology, measured or modelled surrogate exposure estimates, prone to measurement error (ME), are used to investigate the health effects of exposure to pollution of outdoor origin, potentially leading to biased effect estimates. We predicted the annual personal exposure from outdoor sources by using personal measurements, compared it with concentrations from surrogate metrics, and quantified the ME magnitude, type, and determinants.

METHODS: We used measurements from four panel studies in London, UK, and predicted personal exposures to fine particulate matter (PM2.5), nitrogen dioxide (NO2), ozone (O3), and black carbon (BC). We compared those with surrogate exposures, including measurements from fixed-site monitors, modelled ambient concentrations, or hybrid methods accounting for people’s mobility. We estimated the exposure ME magnitude, correlations, and variance ratios between surrogate measures and personal exposure, and the percentages of classical/Berkson-type errors. Individual- and area-level characteristics, such as age, sex, socio-economic status, and time spent outdoors, were assessed as potential error determinants.

RESULTS: Predicted annual personal exposures to PM2.5, NO2, O3, and BC from outdoor sources were overestimated by surrogate metrics, with mean differences of up to 10.1, 40.0, 61.7, and 2.6 μg/m3, respectively. The variance ratios and Pearson correlation coefficients between surrogate and predicted personal exposures ranged from 0.03 to 165.02 and -0.24 to 0.25. Time-activity adjustment reduced errors substantially. Berkson-type errors dominated the ME for PM2.5 and BC (43%-81% and 26%-98%, respectively), whilst classical errors characterized gases (>94% for both NO2 and O3). Time spent outdoors, house type, and deprivation were associated with exposure error.

CONCLUSION: The use of surrogate exposures to investigate the health effects of long-term exposure to air pollution from outdoor sources may bias the epidemiological estimates due to ME. Information about the error structures and their determinants can be used for correction and the identification of the true exposure-response functions.

PMID:41481245 | DOI:10.1093/ije/dyaf214

Int J Epidemiol. 2026 Jan 2;55(1):dyaf208. doi: 10.1093/ije/dyaf208.

ABSTRACT

BACKGROUND: By mid-2024, >13 billion COVID-19 vaccine doses had been administered globally, with totals continuing to rise into 2025, yet persistent inequities remain in low- and middle-income countries (LMICs). We examined spatial determinants of COVID-19 vaccination uptake (proportion of eligible persons vaccinated) in Kenya by using the most recent nationally representative survey, the Kenya Demographic and Health Survey 2022. Our central contribution is the detection of seven spatially concentrated vulnerability clusters, complemented by using a Development Index (DI) and equity auditing to guide targeted action.

METHODS: We integrated socioeconomic, healthcare, environmental, and demographic measures at the Demographic and Health Survey cluster level; quantified spatial dependence (Moran’s I; spatial lag models); identified socio-geographic clusters (K-means); estimated variable importance (random forest); and synthesized a DI. Equity was assessed by using the Erreygers Concentration Index (ECI) along two axes: wealth-based (poorest→richest) and immunization-linked (lowest→highest routine child immunization coverage).

RESULTS: Our results reveal stark geographic disparities: vaccination rates range from 5.93% in Garissa to 46.02% in Nyeri, with urban clusters achieving significantly higher uptake. Key predictors include bank access (financial inclusion), household crowding, and environmental factors (nitrogen dioxide levels, precipitation). The DI correlated positively with uptake and the ECI indicated modest immunization-linked inequality and more pronounced wealth-related inequality.

CONCLUSION: This study underscores the need for targeted interventions, including mobile vaccination units, financial inclusion programs (e.g. M-Pesa subsidies), and the integration of COVID-19 vaccines into routine immunization programs. As Kenya and many LMICs integrate COVID-19 vaccination into routine immunization, our spatial approach, combining DI, cluster detection, and equity metrics, provides an operational toolkit to prioritize underserved areas, inform the placement of service points/mobile teams, and monitor equity as programs transition from campaigns to routine delivery.

PMID:41481244 | DOI:10.1093/ije/dyaf208

Int J Epidemiol. 2026 Jan 2;55(1):dyaf215. doi: 10.1093/ije/dyaf215.

NO ABSTRACT

PMID:41481241 | DOI:10.1093/ije/dyaf215

Int J Epidemiol. 2026 Jan 2;55(1):dyaf213. doi: 10.1093/ije/dyaf213.

ABSTRACT

BACKGROUND: Epidemiological studies evaluating the potential association between oral contraceptive (OC) use and melanoma risk have reported conflicting results. We assessed the association of OC use with melanoma risk in a large prospective cohort.

METHODS: The Nightingale Study comprises 59 944 Dutch female nurses at ages 19-65 years (mean, 46.9 years; SD, 11.0) who completed a baseline questionnaire in 2011, including information on lifetime OC use. Melanoma incidence was retrieved through linkage with the Netherlands Cancer Registry. Associations between lifetime OC use and risk of melanoma were assessed by using Cox proportional hazard models. Women who used OCs at baseline were considered current users and women who had used OCs but stopped before baseline were considered former users. Never OC users were defined as the reference.

RESULTS: During 10 years of follow-up, 447 women were diagnosed with melanoma. Melanoma risk was not increased among women who used OCs for a duration of <9, 10-15, or ≥16 years compared with never CO users. Melanoma risk was increased for current OC users [hazard ratio (HR), 1.53; 95% confidence interval (CI), 1.03-2.29], without a trend with duration of use (P-trend = .42) and age at cohort entry (P-trend = .05). Melanoma risk was not increased among former OC users (HR, 0.99; 95% CI, 0.72-1.38) nor when they had last used OC <2 years before baseline (HR, 0.69; 95% CI, 0.36-1.32).

CONCLUSION: Current OC use was associated with increased melanoma risk, irrespective of the duration or recency of use.

PMID:41481240 | DOI:10.1093/ije/dyaf213

Int J Epidemiol. 2026 Jan 2;55(1):dyaf212. doi: 10.1093/ije/dyaf212.

ABSTRACT

BACKGROUND: The association between wildfire smoke (WFS) exposure and pregnancy loss has been understudied. Here, we examined the association between prenatal wildfire-specific particulate matter ≤2.5 µm (PM2.5) exposure and pregnancy loss in Colorado, USA.

METHODS: We retrieved all birth records from the 17 ‘Front Range’ counties (just east of the Rocky Mountains) of Colorado from 2007 to 2018 (n = 614 321). We considered two PM2.5 exposures-wildfire-specific PM2.5 from a novel machine learning model and non-wildfire PM2.5 constructed using the Community Multiscale Air Quality model. We fitted quasi-Poisson distributed lag models to estimate the associations between the two weekly-resolved PM2.5 exposures during pregnancy and live birth-identified conceptions (LBICs) in each county. That is, we used the predicted change in the LBICs to directly infer the change in the number of pregnancy losses due to the exposure.

RESULTS: Average weekly non-wildfire PM2.5 was 6.2 µg/m3 (SD 2.3). In weeks with non-zero WFS (27% of all county-weeks), the average wildfire-specific PM2.5 was 0.92 µg/m3 (SD: 1.55). Wildfire-specific PM2.5 appeared important in gestational weeks 6-13-a 1-µg/m3 higher exposure sustained in these gestational weeks was associated with 20 [95% confidence interval (CI): 4-34] losses/year. In contrast, the cumulative association with non-wildfire PM2.5 was stronger-a 1-µg/m3 higher exposure sustained in every week of pregnancy was associated with 84 (95% CI: 46-129) losses/year.

CONCLUSION: Our findings suggest that both wildfire-specific and non-wildfire PM2.5 exposures were associated with more pregnancy loss and add to the growing literature on the harmful effects of wildfires and, more broadly, air pollution.

PMID:41481237 | DOI:10.1093/ije/dyaf212

J Environ Sci Health B. 2026 Jan 2:1-11. doi: 10.1080/03601234.2025.2608417. Online ahead of print.

ABSTRACT

Agriculture represents a cornerstone of the Algerian economy. To sustain agricultural production, fungicides, including the Bordeaux mixture, a copper (Cu)-based fungicide, are used extensively. The amounts applied, along with the frequency of their use in the absence of adequate regulatory oversight, raise significant concerns. Bou-Ismaïl Bay receives this compound through runoff and urban discharge. Cu is essential at low doses; however, at higher levels, it can cause serious toxicity. Here, 120 sardines were sampled from Bou-Ismaïl Bay in February and May 2023. Cu concentrations in the tissues were measured using atomic absorption spectrophotometry. Statistical analyses were conducted using R version 4.3.2. The results revealed a significant difference between the tissues. Concentrations ranged from 0.581 to 9.032 µg/g in the gills and from 0.378 to 1.543 µg/g in the muscle. The maximum Cu concentrations in the gills in February and May indicate chronic contamination of the marine environment. The Cu content in sardines was closely linked to the extent of agricultural land using the Bordeaux mixture. The absence of international maximum permissible levels of Cu specifically for sardines increases the potential risk of consumer overexposure. This regulatory gap, combined with the limited research on Cu’s effects in coastal populations, represents a significant concern.

PMID:41481209 | DOI:10.1080/03601234.2025.2608417