Association Between Pollution and Frailty in Older People: A Cross-Sectional Analysis of the UK Biobank

Abstract

Objectives: Frailty is a relevant issue in older people, being associated with several negative outcomes. Increasing literature is reporting that pollution (particularly air pollution) can increase the risk of frailty, but the research is still limited. We aimed to investigate the potential association of pollution (air, noise) with frailty and prefrailty among participants 60 years and older of the UK Biobank study.

Design: Cross-sectional.

Settings and participants: Older participants (age ≥ 60 years) participating to the UK Biobank.

Methods: Frailty and prefrailty presence were ascertained using a model including 5 indicators (weakness, slowness, weight loss, low physical activity, and exhaustion). Air pollution was measured through residential exposures to nitrogen oxides (NO_x) and particulate matter (PM_2.5, PM_2.5-10, PM₁₀). The average residential sound level during the daytime, the evening, and night was used as an index for noise pollution.

Results: A total of 220,079 subjects, aged 60 years and older, was included. The partial proportional odds model, adjusted for several confounders, showed that the increment in the exposure to NO_x was associated with a higher probability of being in both the prefrail and frail category [odds ratio (OR) 1.003; 95% CI 1.001-1.004]. Similarly, the increase in the exposure to PM_2.5-10 was associated with a higher probability of being prefrail and frail (OR 1.014; 95% CI 1.001-1.036), such as the increment in the exposure to PM_2.5 that was associated with a higher probability of being frail (OR 1.018; 95% CI 1.001-1.037).

Conclusions and implications: Our study indicates that the exposure to air pollutants as PM_2.5, PM_2.5-10, or NO_x might be associated with frailty and prefrailty, suggesting that air pollution can contribute to frailty and indicating that the frailty prevention and intervention strategies should take into account the dangerous impact of air pollutants.

Keywords: Pollution; UK Biobank; epidemiology; frailty.