According to a new study published in The Journal of Clinical Endocrinology and Metabolism, higher body mass index (BMI) and serum urate levels are independently associated with a lower risk of developing dementia, including Alzheimer’s disease and vascular dementia.
In a prospective population-based cohort study, researchers analysed 502,528 individuals aged 37-73 years from the UK Biobank for whom BMI and serum urate levels were recorded between 2006 and 2010.
After adjusting for potential confounding variables, underweight individuals had an increased risk of dementia (HR, 2.00; 95% CI, 1.29-3.09). The risk of dementia continued to decline with increasing weight, with overweight and obese individuals having a 22 per cent (HR, 0.78; 95% CI, 0.70-0.87) and 27 per cent (HR, 0.73; 95% CI, 0.65-0.82) lower likelihood of developing dementia, respectively, compared with healthy weight individuals.
Individuals in the highest quintile of serum urate had a 25 per cent (HR, 0.75; 95% CI, 0.64-0.87) lower likelihood of dementia diagnosis, compared with those in the lowest quintile. Furthermore, the association between urate and dementia was influenced by BMI, with the protective effect of higher urate levels on dementia risk being stronger in individuals with obesity.
The authors commented: "It is necessary to revisit the causes and public health consequences of these inverse associations of BMI and urate with dementia." They call for further research to investigate the mechanisms underlying these associations.