Abstract
BACKGROUND: The impact of adherence to low-risk lifestyle factors on dementia risk in individuals with obesity remains unclear. We aimed to explore the association between healthy lifestyles with dementia in obese participants.
METHODS: Dementia-free participants from the UK Biobank, aged 50 years or older with obesity (BMI ≥30 kg/m2) at baseline were included. A weighted healthy lifestyle score was calculated incorporating both traditional and emerging lifestyle factors. The primary outcome was all-cause dementia and its subtypes (Alzheimer’s disease and Vascular dementia). Cox regression models analyzed the association between healthy lifestyle scores and dementia risk. Restricted cubic splines tested the dose-response. We also examined the effect of lifestyle scores on dementia risk in individuals with normal weight and overweight.
RESULTS: A total of 54,365 participants were included at baseline. During a median follow-up of 14.4 years, 1271 participants developed all-cause dementia, including 537 cases of Alzheimer’s disease and 343 cases of vascular dementia. A 20 % increase in the lifestyle score was associated with a 7 % reduction in dementia risk (HR: 0.93; 95 % CI: 0.91,0.96) and a 4 % reduction in Alzheimer’s disease risk (HR: 0.96; 95 % CI: 0.92,1.00). The association was stronger in overweight and obese participants. No significant link was found for vascular dementia.
LIMITATIONS: Information on lifestyle behaviors was self-reported and might be prone to measurement error.
CONCLUSIONS: Adherence to a healthy lifestyle may reduce the risk of dementia and Alzheimer’s disease in older obese individuals, with a stronger effect observed in those with higher lifestyle scores.