Kidney Medicine (May 2024)
The 10-Year Effects of Intensive Lifestyle Intervention on Kidney Outcomes
Abstract
Rationale & Objective: Limited data exist on longitudinal kidney outcomes after nonsurgical obesity treatments. We investigated the effects of intensive lifestyle intervention on kidney function over 10 years. Study Design: Post hoc analysis of Action for Health in Diabetes (Look AHEAD) randomized controlled trial. Setting & Participants: We studied 4,901 individuals with type 2 diabetes and body mass index of ≥25 kg/m2 enrolled in Look AHEAD (2001–2015). The original Look AHEAD trial excluded individuals with 4+ urine dipstick protein, serum creatinine level of >1.4 mg/dL (women), 1.5 mg/dL (men), or dialysis dependence. Exposures: Intensive lifestyle intervention versus diabetes support and education (ie, usual care). Outcome: Primary outcome was estimated glomerular filtration rate (eGFR, mL/min/1.73 m2) slope. Secondary outcomes were mean eGFR, slope, and mean urine albumin to creatinine ratio (UACR, mg/mg). Analytical Approach: Linear mixed-effects models with random slopes and intercepts to evaluate the association between randomization arms and within-individual repeated measures of eGFR and UACR. We tested for effect modification by baseline eGFR. Results: At baseline, mean eGFR was 89, and 83% had a normal UACR. Over 10 years, there was no difference in eGFR slope (+0.064 per year; 95% CI: –0.036 to 0.16; P = 0.21) between arms. Slope or mean UACR did not differ between arms. Baseline eGFR, categorized as eGFR of 100, did not modify the intervention’s effect on eGFR slope or mean. Limitations: Loss of muscle may confound creatinine-based eGFR. Conclusions: In patients with type 2 diabetes and preserved kidney function, intensive lifestyle intervention did not change eGFR slope over 10 years. Among participants with baseline eGFR <80, lifestyle intervention had a slightly higher longitudinal mean eGFR than usual care. Further studies evaluating the effects of intensive lifestyle intervention in people with kidney disease are needed. Plain-Language Summary: Lifestyle interventions can improve chronic kidney disease risk factors, specifically diabetes, hypertension, and obesity. But, the effects of lifestyle intervention on change in kidney function (estimated glomerular filtration rate [eGFR]) over time are not well established. We studied Action for Health in Diabetes (Look AHEAD) trial data because all participants were affected by diabetes and overweight or obesity. Look AHEAD randomized participants to intensive lifestyle intervention or diabetes support and education (ie, usual care). We compared eGFR change over 10 years between groups, but found no difference. However, the intervention group maintained slightly higher eGFR than usual care, especially if eGFR was relatively low at baseline. Our study suggests lifestyle intervention may preserve eGFR, but dedicated studies in individuals with chronic kidney disease are needed.