Association between fine particulate matter (PM2.5) and infant mortality in a North Carolina birth cohort (2003-2015).

Background: While the association between fine particulate matter (PM2.5) and adult mortality is well established, few studies have examined the association between long-term PM2.5 exposure and infant mortality. Methods: We conducted an unmatched case-control study of 5992 infant mortality cases and 60,000 randomly selected controls from a North Carolina birth cohort (2003-2015). PM2.5 during critical exposure periods (trimesters, pregnancy, first month alive) was estimated using residential address and a national spatiotemporal model at census block centroid. We fit adjusted logistic regression models and calculated odds ratios (ORs) and 95% confidence intervals (CIs). Due to differences in PM2 .5 over time, we stratified analyses into two periods: 2003-2009 (mean = 12.1 µg/m3, interquartile range [IQR]: 10.8-13.5) and 2011-2015 (mean = 8.4 µg/m3, IQR: 7.7-9.0). We assessed effect measure modification by birthing parent race/ethnicity, full-term birth, and PM2.5 concentrations. Results: For births 2003-2015, the odds of infant mortality increased by 12% (95% CI: 1.06, 1.17) per 4.0 µg/m3 increase in PM2.5 exposure averaged over the pregnancy. After stratifying, we observed an increase of 4% (95% CI: 0.95, 1.14) for births in 2003-2009 and a decrease of 15% (95% CI: 0.72, 1.01) for births in 2011-2015. Among infants with higher PM2.5 exposure (≥12 µg/m3) during pregnancy, the odds of infant mortality increased (OR: 2.69; 95% CI: 2.17, 3.34) whereas the lower exposure (<8 µg/m3) group reported decreased odds (OR: 0.50; 95% CI: 0.28, 0.89). Conclusions: We observed differing associations of PM2.5 exposure with infant mortality across higher versus lower PM2.5 concentrations. Research findings suggest the importance of accounting for long-term trends of decreasing PM2.5 concentrations in future research.

Self-reported condom use among Washington State residents prior to and during the COVID-19 pandemic: a cross-sectional analysis of BRFSS data.

OBJECTIVES: COVID-19 significantly impacted healthcare access and sexual behaviour, but little is known about how COVID-19 affected condom use. This study aimed to investigate whether self-reported condom use and sex in Washington State changed during pandemic restrictions compared with prepandemic. DESIGN: Cross-sectional survey data from the Behavioral Risk Factor Surveillance System. SETTING: Washington State. PARTICIPANTS: 11 684 participants aged 18-65. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was changes in the prevalence of condom use by time of interview pre-COVID-19, before the Washington State lockdown (1 January 2019 to 23 March 2020, n=7708) and during COVID-19, after the first state lockdown (24 March 2020 to 31 December 2020, n=3976). The secondary outcome was changes in the prevalence of reported sex during the same periods. We assessed whether associations differed by rurality and HIV risk behaviour. RESULTS: Condom use was similar during COVID-19 (37.3%) compared with pre-COVID-19 (37.8%) (adjusted prevalence ratio (PR): 0.98, 95% CI 0.89, 1.01). Associations did not differ by rurality or HIV risk behaviour. Compared with pre-COVID-19 (83.0%), a smaller proportion of respondents reported having sex in the last 12 months during COVID-19 (80.5%), a relative decrease of 3% (PR: 0.97, 95% CI 0.96, 0.99; p<0.001). CONCLUSIONS: The prevalence of reported sex declined during COVID-19, but condom use remained steady in Washington. As our reproductive health system faces increased challenges, these results may inform future sexual health services.