Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
BMJ Open. 2019 Aug 30;9(8):e030661. doi: 10.1136/bmjopen-2019-030661.
To examine whether lifestyle factors, including sedentary time and physical activity, could independently contribute to risk of end-stage renal disease (ESRD).
Case-cohort study.
South-eastern USA.
The Southern Community Cohort Study recruited ~86 000 black and white participants from 2002 to 2009. We assembled a case cohort of 692 incident ESRD cases and a probability sample of 4113 participants.
Sedentary time was calculated as hours/day from daily sitting activities. Physical activity was calculated as metabolic equivalent (MET)-hours/day from engagement in light, moderate and vigorous activities.
Incident ESRD.
At baseline, among the subcohort, mean (SD) age was 52 (8.6) years, and median (25th, 75th centile) estimated glomerular filtration rate (eGFR) was 102.8 (85.9-117.9) mL/min/1.73 m. Medians (25th-75th centile) for sedentary time and physical activity were 8.0 (5.5-12.0) hours/day and 17.2 (8.7-31.9) MET-hours/day, respectively. Median follow-up was 9.4 years. We observed significant interactions between eGFR and both physical activity and sedentary behaviour (p<0.001). The partial effect plot of the association between physical activity and log relative hazard of ESRD suggests that ESRD risk decreases as physical activity increases when eGFR is 90 mL/min/1.73 m. The inverse association is most pronounced at physical activity levels >27 MET-hours/day. High levels of sitting time were associated with increased ESRD risk only among those with reduced kidney function (eGFR ≤30 mL/min/1.73 m); this association was attenuated after excluding the first 2 years of follow-up.
In a population with a high prevalence of chronic kidney disease risk factors such as hypertension and diabetes, physical activity appears to be associated with reduced risk of ESRD among those with preserved kidney function. A positive association between sitting time and ESRD observed among those with advanced kidney disease is likely due to reverse causation.
研究生活方式因素（包括久坐时间和体力活动）是否可独立导致终末期肾病（ESRD）的发生。
病例-队列研究。
美国东南部。
南方社区队列研究于 2002 年至 2009 年招募了约 86000 名黑人和白人参与者。我们组建了一个由 692 例 ESRD 新发病例组成的病例队列和一个由 4113 例参与者组成的概率样本。
久坐时间以每天的静坐活动时间计算。体力活动以轻、中、高强度活动的代谢当量（MET）-小时/天计算。
ESRD 的发生。
在亚队列中，基线时平均（SD）年龄为 52（8.6）岁，中位（25 分位数，75 分位数）估计肾小球滤过率（eGFR）为 102.8（85.9-117.9）mL/min/1.73m2。久坐时间和体力活动的中位数（25 分位数-75 分位数）分别为 8.0（5.5-12.0）小时/天和 17.2（8.7-31.9）MET-h/天。中位随访时间为 9.4 年。我们观察到 eGFR 与体力活动和久坐行为之间存在显著的交互作用（p<0.001）。体力活动与 ESRD 对数相对危险之间关联的部分效应图表明，当 eGFR 为 90mL/min/1.73m2 时，体力活动增加，ESRD 风险降低。在体力活动水平>27MET-h/天的情况下，这种关联最为明显。久坐时间水平较高与肾功能下降（eGFR≤30mL/min/1.73m2）者的 ESRD 风险增加有关；在排除随访前 2 年的影响后，这种关联减弱。
在高血压和糖尿病等慢性肾脏病危险因素高发的人群中，体力活动似乎与肾功能正常者的 ESRD 风险降低有关。在肾功能下降者中观察到的久坐时间与 ESRD 之间的正相关可能是由于反向因果关系所致。
