Abstract

Background

Association between physical activity and decline in renal function among the general population is not fully understood.

Methods

This is a longitudinal study on subjects who participated in the Japanese nationwide Specific Health Checkup program between 2008 and 2014. The exposure of interest was baseline self-reported walking habit. The outcomes were annual change and incidence of 30% decline in estimated glomerular filtration rate (eGFR). Changes in eGFR were compared using a linear mixed-effects model. Cox proportional hazard models were used to examine the association between self-reported walking habit and 30% decline in eGFR.

Results

Among 332,166 subjects, 168,574 reported walking habit at baseline. The annual changes in eGFR [95% confidence interval (CI)] among subjects with and without baseline self-reported walking habit were − 0.17 (− 0.19 to − 0.16) and − 0.26 (− 0.27 to − 0.24) mL/min/1.73 m²/year, respectively (P for interaction between time and baseline self-reported walking habit, < 0.001). During a median follow-up of 3.3 years, 9166 of 314,489 subjects exhibited 30% decline in eGFR. The incidence of 30% decline in eGFR was significantly lower among subjects with self-reported walking habit after adjustment for potential confounders including time-varying blood pressure, body mass index, lipid profile, and hemoglobin A1c, with hazard ratio (95% CI) of 0.93 (0.89–0.97). Sensitivity analysis restricted to subjects with unchanged self-reported walking habit from baseline or analysis with time-varying self-reported walking habit yielded similar results.

Conclusions

Self-reported walking habit was associated with significantly slower decline in eGFR. This association appeared to be independent of its effects on metabolic improvement.

Graphic abstract