Long Term Effect of Intensive Lifestyle Intervention on Cerebral Blood Flow

To determine whether long-term behavioral intervention targeting weight loss through increased physical activity and reduced caloric intake would alter cerebral blood flow (CBF) in individuals with type 2 diabetes mellitus.

Postrandomization assessment of CBF.

Action for Health in Diabetes multicenter randomized controlled clinical trial.

Individuals with type 2 diabetes mellitus who were overweight or obese and aged 45 to 76 (N = 310).

A multidomain intensive lifestyle intervention (ILI) to induce weight loss and increase physical activity for 8 to 11 years or diabetes support and education (DSE), a control condition.

Participants underwent cognitive assessment and standardized brain magnetic resonance imaging (MRI) (3.0 Tesla) to assess CBF an average of 10.4 years after randomization.

Weight changes from baseline to time of MRI averaged -6.2% for ILI and -2.8% for DSE (P < .001), and increases in self-reported moderate or intense physical activity averaged 444.3 kcal/wk for ILI and 114.8 kcal/wk for DSE (P = .03). Overall mean CBF was 6% greater for ILI than DSE (P = .04), with the largest mean differences between ILI and DSE in the limbic region (3.39 mL/100 g per minute, 95% confidence interval (CI) = 0.07-6.70 mL/100 g per minute) and occipital lobes (3.52 mL/100 g per minute, 95% CI = 0.20-6.84 mL/100 g per minute). In ILI, greater CBF was associated with greater decreases in weight and greater increases in physical activity. The relationship between CBF and scores on a composite measure of cognitive function varied between intervention groups (P = .02).

Long-term weight loss intervention in overweight and obese adults with type 2 diabetes mellitus is associated with greater CBF.