Sustained Weight Loss Linked to Lower Renal Risk in Diabetes

TOPLINE:

Patients with overweight/obesity and type 2 diabetes who lose ≥ 7% of their body weight and maintain it for longer may lower their risk for kidney outcomes.

METHODOLOGY:

• Researchers conducted a post hoc analysis of the Look AHEAD trial including 3601 adults with a body mass index of > 25 kg/m² and a diagnosis of type 2 diabetes. The mean age was 59 years, and 2140 (59%) were women.
• Body weight time in target range (TTR), a new indicator of weight management, was defined as the proportion of time during the first 4 years when weight was within the weight-loss target of ≥ 7% from baseline.
• Body weight TTR during the first 4 years was assessed in three evenly divided categories ranging from > 0% to < 100%, using 0% as the reference group.
• Patients were randomly assigned to an intensive lifestyle intervention group of reduced caloric intake and increased physical activity or a control diabetes support and education group that focused on exercise, diet, and social support.
• The primary outcome was the composite kidney outcome, defined as ≥ 30% decrease in estimated glomerular filtration rate to < 60 mL/min/1.73 m², end-stage kidney disease, or self-reported kidney failure.

TAKEAWAY:

• During a median follow-up of 8 years, composite kidney outcome was reported in 435 participants.
• During the first 4 years, body weight TTR was inversely associated with the subsequent risk for composite kidney outcome (adjusted hazard ratio [aHR], 0.81; P < .001).
• The inverse association between body weight TTR and composite kidney outcome was stronger in the intense intervention group (aHR, 0.77; 95% CI, 0.66-0.89) but not significant in the control group.
• Compared with participants having a body weight TTR of 0%, the aHRs of composite kidney outcomes were 0.73 (95% CI, 0.54-1.00) for a TTR of > 0% to < 29.9%, 0.71 (95% CI, 0.52-0.99) for a TTR of 29.9% to < 69.7%, and 0.54 (95% CI, 0.36-0.80) for a TTR of 69.7% to < 100%.

IN PRACTICE:

"Even a single-digit sustained weight loss can bring significant renal benefits," the authors wrote, emphasizing the importance of weight control through caloric restriction and physical activity in patients with overweight/obesity and type 2 diabetes.

SOURCE:

Xianhui Qin of the Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, China, was the corresponding author of this study, which was published online on December 11, 2023, in Diabetes Care.

LIMITATIONS:

The participants' body weight was measured annually, and body weight TTR was computed using the results of at least three body weight measurements taken over the first 4 years. Because weight change is a gradual process, these data may not accurately reflect the actual time spent within the target weight range. Given the novelty of the body weight TTR concept, the authors noted, the findings are hypothesis generating and should be interpreted with greater caution.

DISCLOSURES:

This study was supported by the National Key Research and Development Program, the National Natural Science Foundation of China and its Key Program, and other sources. The authors declared no conflicts of interest.