Calorie restriction blunts long-term kidney decline, improves CV risk factors in obese T2D patients

In type 2 diabetes (T2D) patients with obesity, calorie restriction helps correct several cardiovascular (CV) risk factors and glomerular hyperfiltration, with the latter translating into a relative long-term stabilization of kidney function, according to a study.

The study included 103 T2D patients with body mass index (BMI) ≥27 kg/m², creatinine <1.2 mg/dL, and albuminuria ≤300 mg/24 hours. They were randomized to 25 percent calorie restriction (n=53) or standard diet (n=50) for 2 years.

The 6-month measured glomerular filtration rate (GFR) was the primary outcome, and researchers performed the analyses by modified intention-to-treat.

At 6 months, GFR markedly decreased by a mean of –5.16 mL/min with calorie restriction (p=0.001) and only by mere –0.98 mL/min (p=0.497) with standard diet. The difference between these two interventions was significant (p=0.044).

Of note, the GFR decline from 6 to 24 months was substantial with standard diet (p<0.01) but not with calorie restriction (p=0.075). However, the between-group difference did not reach statistical significance (p=0.414).

The group who underwent calorie restriction also showed marked improvements in body weight, BMI, waist circumference, systolic blood pressure, HbA1c, blood glucose, serum triglycerides, and ApoA-I concentration. These changes were not observed in the standard diet group.

In terms of safety, calorie restriction was tolerated well.

The findings show that calorie restriction helps slow progressive renal function deterioration and limit the excess CV morbidity that characterizes this population. Thus, it could be an important therapeutic option in addition to available pharmacological medications, the researchers said.