Risk factors in household environments related to cardiovascular health outcomes of the elderly in Shanghai, China

Older adults face an elevated risk of cardiovascular disease (CVD), with an indoor environment representing a critical but under-researched determinant. Amid increasing residential indoor pollution, this study monitored indoor environmental parameters and cardiovascular health indicators amongst older adults in 37 Shanghai households from January 2019 to January 2020. Seasonal data were analysed using covariate adjustment to account for confounders and factor analysis to reduce dimensionality and assess combined environmental effects. Hypertension and hyperlipidaemia were highly prevalent, with approximately 50% of participants presenting at least one condition. Strong associations were observed between these cardiovascular disorders and homes with solid wood flooring and latex-painted walls. In winter, each 1°C reduction in indoor temperature correlated with a 2.14 mm Hg increase in systolic blood pressure ( β = −2.14, p < 0.05), while higher relative humidity was positively linked to blood pressure ( β = 0.73, p < 0.05). Composite environmental factors exhibited stronger associations than single variables, despite limited overall explanatory power. Annual trends showed an increasing heart rate (slope = 1.50) and decreasing systolic and diastolic blood pressure (slopes = −1.24, −1.40). These findings demonstrate that indoor environments are associated with cardiovascular physiology in older adults, identifying actionable targets for CVD prevention and integrated environmental health assessment.