Risk factors for renal function decline in adults with normal kidney function: A 7-year cohort study

Background: We aimed to examine the risk factors for renal function decline (RFD) in a community-based cohort of a rural Chinese population with normal kidney function (estimated glomerular filtration rate, eGFR ≥60 mL/min/1.73 m²), both for the population as a whole and stratified by sex. Methods: 2518 participants were included in the current analysis. RFD was defined as follows: a drop in the eGFR category accompanied by a 25% or greater drop in eGFR from baseline; or a sustained decline in eGFR of more than 5 mL/min/1.73 m²/year. Results: The incidence rate of RFD was 8.7% (women 7.4% and men 9.8%). In the multivariable logistic regression model, the ORs (95% CI) of developing RFD was 1.60 (1.01 to 2.54) for men versus women, and 1.51 (1.09 to 2.08) for participants with obesity or abdominal obesity versus none (1.35 (0.85 to 2.14) for men, and 1.65 (1.04 to 2.64) for women). However, prehypertension (OR=1.64; 95% CI 1.02 to 2.63) or hypertension (2.05; 1.21 to 3.47), higher mean blood pressure (≥90 vs <80 mm Hg, 2.63; 1.11 to 6.20), higher pulse pressure (≥50 vs <40 mm Hg, 2.00; 1.26 to 3.18), lower high-density lipoprotein cholesterol (<0.9 vs ≥0.9 mmol/L, 2.65; 1.08 to 6.50) and low physical activity levels (vs high, 3.11; 1.59 to 6.10) were major risk factors for RFD in men. Current smoking (3.22; 1.22 to 2.64) and worse self-reported health (vs better, 2.57; 1.20 to 5.50) were major risk factors for RFD in women. Conclusions: Our findings suggested that sex-specific risk factors should be considered in prevention of RFD in the Chinese rural population with normal kidney function.