Effect of a long-term intensive lifestyle intervention on prevalence of cognitive impairment

Abstract

Objective: To assess whether an average of 10 years of lifestyle intervention designed to reduce weight and increase physical activity lowers the prevalence of cognitive impairment among adults at increased risk due to type 2 diabetes and obesity or overweight.Methods: Central adjudication of mild cognitive impairment and probable dementia was based on standardized cognitive test battery scores administered to 3,802 individuals who had been randomly assigned, with equal probability, to either the lifestyle intervention or the diabetes support and education control. When scores fell below a prespecified threshold, functional information was obtained through proxy interview.Results: Compared with control, the intensive lifestyle intervention induced and maintained marked differences in weight loss and self-reported physical activity throughout follow-up. At an average (range) of 11.4 (9.5-13.5) years after enrollment, when participants' mean age was 69.6 (54.9-87.2) years, the prevalence of mild cognitive impairment and probable dementia was 6.4% and 1.8%, respectively, in the intervention group, compared with 6.6% and 1.8%, respectively, in the control group (p 5 0.93). The lack of an intervention effect on the prevalence of cognitive impairment was consistent among individuals grouped by cardiovascular disease history, diabetes duration, sex, and APOE e4 allele status (all p $ 0.50). However, there was evidence (p 5 0.03) that the intervention effect ranged from benefit to harm across participants ordered from lowest to highest baseline BMI.Conclusions: Ten years of behavioral weight loss intervention did not result in an overall difference in the prevalence of cognitive impairment among overweight or obese adults with type 2 diabetes. Clinicaltrials.gov identifier: NCT00017953 (Action for Health in Diabetes).Level of evidence: This study provides Class II evidence that for overweight adults with type 2 diabetes, a lifestyle intervention designed to reduce weight and increase physical activity does not lower the risk of cognitive impairment. Neurology ® 2017;88:2026-2035 GLOSSARY 3MSE 5 Modified Mini-Mental State Examination; BMI 5 body mass index; DSE 5 diabetes support and education; FAQ 5 Functional Assessment Questionnaire; HbA1c 5 glycated hemoglobin; ILI 5 intensive lifestyle intervention; MCI 5 mild cognitive impairment; OR 5 odds ratio.

The effects of weight loss and metformin on cognition among breast cancer survivors: Evidence from the Reach for Health study

“…These differences in populations, amount of weight loss achieved, and differences in exercise prescriptions across interventions are all possible reasons why findings from the current study may contrast with previous reports. However, our results were consistent with the Look AHEAD trial of over 3000 type 2 diabetics where a weight loss intervention was not shown to improve cognition . Weight loss or metformin may not be effective strategies to improve cognition for many breast cancer survivors.…”

“…33 where a weight loss intervention was not shown to improve cognition. 21 Weight loss or metformin may not be effective strategies to improve cognition for many breast cancer survivors.…”

“…19 In contrast to this meta-analysis, the Look AHEAD trial, with 3802 overweight or obese adults with type 2 diabetes, which evaluated a 10year weight loss intervention, did not reduce the risk of cognitive impairment or dementia. 21 The discrepant findings between the generally healthy populations in the meta-analysis and a sample with type 2 diabetes highlight the need to examine this in cancer survivors separately.…”

Obesity as a risk factor for Alzheimer's disease: weighing the evidence

“…In the ACCORD MIND sub-study, participants with long-duration T2D and high CV risk with intensive glucose, blood pressure, and lipid control did not have a reduction in cognitive decline over the 40-month follow-up period (54). Similarly, the Action for Health in Diabetes (Look AHEAD) research group reported that obese or overweight subjects with T2D assigned to a 10-year intensive lifestyle intervention (ILI) did not show better cognitive function compared with those assigned to diabetes support and education despite significantly greater weight loss in the ILI group (55). In Look AHEAD, cognitive function was not assessed at baseline prior to the intervention, and the absolute difference in weight at 10 years was small albeit statistically significant.…”

Dementia outcomes after addition of proxy‐based assessments for deceased or proxy‐dependent participants

“…2,3 In research contexts, evaluating participants' cognitive status is challenging because of the high cost of a comprehensive evaluation that includes neurocognitive testing, a clinical evaluation, interviewing knowledgeable family members, and optional ancillary laboratory tests or brain scans. 2,3 In research contexts, evaluating participants' cognitive status is challenging because of the high cost of a comprehensive evaluation that includes neurocognitive testing, a clinical evaluation, interviewing knowledgeable family members, and optional ancillary laboratory tests or brain scans.…”