Climate change leads to more days with extremely hot temperatures. Previous analyses of heat waves have documented a short-term rise in mortality. The results on the relationship between high temperatures and hospitalisations, especially in vulnerable patients admitted to nursing homes, are inconsistent. The objective of this research was to examine the discrepancy between heat-related mortality and morbidity in nursing homes. A time-stratified case-crossover study about the impact of heat waves on mortality and hospitalisations between 1 January 2013 and 31 December 2017 was conducted in 10 nursing homes over 5 years in Flanders, Belgium. In this study, the events were deaths and hospitalisations. We selected our control days during the same month as the events and matched them by day of the week. Heat waves were the exposure. Conditional logistic regression models were applied. The associations were reported as odds ratios at lag 0, 1, 2, and 3 and their 95% confidence intervals. In the investigated time period, 3048 hospitalisations took place and 1888 residents died. The conditional logistic regression showed that odds ratios of mortality and hospitalisations during heat waves were 1.61 (95% confidence interval 1.10–2.37) and 0.96 (95% confidence interval 0.67–1.36), respectively, at lag 0. Therefore, the increase in mortality during heat waves was statistically significant, but no significant changes in hospitalisations were obtained. Our result suggests that heat waves have an adverse effect on mortality in Flemish nursing homes but have no significant effect on the number of hospitalisations.

Urban green spaces (UGS) may improve mental health in high-income countries. However, evidence from low-income African countries is scarce. Here, we assessed the associations of UGS with depressive and anxiety symptoms among adult residents of Kampala District (Uganda), the potential effect modification by sociodemographic factors, and the mediation roles of social interaction, outdoor physical activity, and residential distance to major roads as a proxy of traffic-related air pollution. We conducted a cross-sectional survey among 641 adults. We objectively measured UGS using the Normalized Difference Vegetation Index (NDVI) within buffers of 100 m and 1,000 m around the residences. We assessed the utilization of UGS as a self-reported frequency (never, occasionally, and frequently) by which individuals visited UGS in the past 6 months. The Patient Health Questionnaire-9 and the Generalized Anxiety Disorder 7-item scale were used to examine the severity of depressive and anxiety symptoms respectively. We used modified Poisson regression models to obtain prevalence ratios (PR) with their 95 % confidence intervals (CI), stratified our models, and conducted mediation analyses. We observed an inverse association between UGS and both outcomes. For example, an inter-quartile range increase in UGS within a 100 m buffer was associated with a 6 % and 8 % decrease in depressive and anxiety symptoms, respectively (PR=0.94; 95 % CI=0.89–0.99, and PR=0.92; 95 % CI=0.85–0.95, respectively). Consistently, frequent visits to UGS relative to no visits were associated with a 33 % and 35 % lower prevalence of depressive and anxiety symptoms (PR=0.67; 95 %CI=0.53–0.84, and PR=0.65; 95 %CI=0.47–0.91, respectively). Depending on the UGS metric, we observed varying potential effect modification findings by sex, age, and educational level. Finally, residential distance to major roads emerged as a mediator in the association between residential surrounding greenness and depressive symptoms. Our study suggests that UGS may also improve the mental health among residents of rapidly urbanizing African low-income cities.

Previous studies on prenatal green space exposure and early respiratory health show inconsistent results. This may reflect stage-specific in utero effects and pollen influence. We examine associations of surrounding greenness and pollen exposure during pregnancy (overall and by trimester) with preschool wheezing, and assess potential mediation by pollen. We used data from the PIPO birth cohort (n = 860). Wheezing was reported biannually between 18 and 48 months of age. Residential greenness was measured with Normalized Difference Vegetation Index (NDVI) in 100 and 250 m buffer. Cumulative grass and birch pollen was estimated using modelled airborne pollen counts and categorized per trimester into no, low and high. All exposures were assessed for the overall pregnancy and per trimester. We used Generalized Estimated Equations to obtain odds ratios (OR) and 95% confidence intervals (CI). To assess mediation by pollen we used a data duplication algorithm with a generalized estimation approach. Approximately 10% of participants wheezed. During pregnancy, greenness (OR = 1.07, CI: 1.05-1.08) and grass pollen exposure (OR = 1.09, CI: 1.03-1.15) increased the odds of wheezing, while birch pollen decreased it (OR = 0.86, CI:0.87-1.00). Per trimester, more greenness during the 2nd trimester increased the odds (OR = 1.21, CI: 1.16-1.26), whereas third-trimester greenness decreased it (OR = 0.87, CI: 0.84-0.91). Grass pollen exposure in the 1st and 3rd trimesters increased the odds of wheezing (OR = 1.23, CI: 1.12-1.34 and OR = 1.13, CI: 1.00-1.27, respectively), while birch pollen exposure in the 1st and 2nd trimesters decreased the odds (OR = 0.88, CI: 0.77-1.00 and OR = 0.83, CI: 0.73-0.95, respectively). No significant associations were found for greenness in the 1st trimester, grass pollen in the 2nd trimester, and birch pollen in the 1st and 3rd trimester. Mediation analysis showed large uncertainty. Surrounding greenness and pollen exposure during pregnancy may impact the likelihood of preschool wheezing differently depending on the timing of exposure and the pollen type.