Differential effects of a multidomain intervention on cognitive decline in older adults with type 2 diabetes according to white matter hyperintensity status: A secondary analysis of the J-MIND-Diabetes.

Abstract

Aims: White matter hyperintensities (WMHs) are commonly observed in older adults with type 2 diabetes. The current study aimed to investigate whether WMH modifies the effects of multidomain intervention in preventing cognitive decline among older adults with type 2 diabetes and mild cognitive impairment.

Materials and methods: This secondary analysis of the Japan-Multidomain Intervention Trial for Prevention of Dementia in Older Adults with Diabetes included 154 participants aged 70-85 years who presented with type 2 diabetes and mild cognitive impairment. They were randomized into the intervention (vascular risk management, exercise, nutritional counselling and promotion of social activities) and control (provision of health-related information) groups. The primary outcome was a change in average Z-scores from all of the neuropsychological tests combined, and secondary outcomes were domain-specific composite scores (memory, executive function and processing speed) from baseline to 18 months. The presence of WMH was assessed using the Fazekas scale. The associations between the intervention and baseline WMH were evaluated using a mixed-effects model for repeated measures.

Results: Among 90 participants included in the analyses, 34 had moderate to severe WMH. At the 18-month follow-up, a significant intervention-WMH interaction (p = 0.017) was found for the primary outcome. The intervention effect was significant in individuals with WMH (Z-score difference: +0.335, 95% confidence interval [CI]: +0.045 to +0.624), but not in individuals without WMH (Z-score difference: -0.121, 95% CI: -0.353 to +0.110).

Conclusions: Older adults with type 2 diabetes and WMH may benefit from multidomain interventions. Further studies should be performed to validate this finding.