Uric acid may be protective against cognitive impairment in older adults, but only in those without cardiovascular risk factors

Abstract

Uric acid (UA) may not only prevent development of cognitive dysfunction owing to its antioxidant efficacy, but also may worsen cognitive functions by gaining pro-oxidant character. The present study attempts to uncover this paradoxical association between UA and cognitive impairment in elderly. 1374 elderly patients were retrospectively evaluated and included in the study. Participants underwent determination of circulating UA levels and comprehensive geriatric assessment. A serum UA concentration≥7.0mg/dL in males and ≥5.7mg/dL in females were considered hyperuricemia. The mean age of patients was 76.72±8.76years. The prevalence of hyperuricemia was 36.6%. Significant differences was determined between the patients with and without hyperuricemia in terms of age, gender, body mass index, score of Charlson Comorbidity Index (CCI), triglyceride level, and the prevalence of dementia, diabetes, hypertension and Congestive Heart Failure (CHF) (p<0.05). When the effect of diabetes, hypertension and CHF between the groups has been statistically adjusted, the prevalence of dementia was significantly higher in those with lower UA in the absence of effect of DM, HT and CHF (p<0.05). Higher UA is associated with better cognitive performance in the absence of cardiovascular risk factors, and these risk factors may potentially suppress this protective effect of higher UA in the older adults.

Keywords: Cardiovascular risk factor; Cognitive function; Dementia; Hyperuricemia; Uric acid.