Association between Light-Intensity and Moderate-to-Vigorous-Intensity Physical Activity Habits and Kidney Dysfunction: A General Population Cohort Study

Abstract

Few studies have considered physical activity (PA) intensity and frequency in relation to kidney dysfunction. This study aimed to investigate the association of regular light intensity, occasional moderate-to-vigorous physical activities, and their combination with kidney function in the general population. This community-based historical cohort study included Japanese people aged ≥40 years. Participants were divided into four groups according to their PA habits: inactive group (neither regular light-intensity physical activity (LPA) nor occasional moderate-to-vigorous physical activity (MVPA)), LPA group (1.5–3.0 metabolic equivalents (METs) for at least 60 min a day), MVPA group (>3.0 METs for at least 30 min twice a week), and LPA + MVPA group (combination of LPA and MVPA). The primary outcome was a 40% decrease in the estimated glomerular filtration rate from the baseline. The Cox proportional hazards model was used to examine the association between PA habits and kidney function. In total, 72,999 participants were included in this study. During the mean follow-up period of 5.9 years, 2,989 (4.1%) participants achieved the outcome. Compared to participants with neither LPA nor MVPA, the adjusted hazard ratios were 0.94 (95% confidence interval (CI), 0.85–1.03; $p=0.182$ ) for LPA alone, 0.97 (95% CI, 0.85–1.10; $p=0.618$ ) for MVPA alone, and 0.83 (95% CI, 0.76–0.91; $p<0.001$ ) for a combination of LPA and MVPA. There was a significant interaction between sex and PA habit ( $p=0.015$ ). Generally, combined LPA and MVPA were associated with a lower risk of kidney dysfunction than was the lack of PA. Future studies are required to determine the PA intensity and duration required to protect kidney function.