Association of serum uric acid level with muscle strength and cognitive function among Chinese aged 50-74 years

• Published in: Geriatrics & gerontology international Vol. 13; no. 3; pp. 672 - 677
• Main Authors: Wu, Yili, Zhang, Dongfeng, Pang, Zengchang, Jiang, Wenjie, Wang, Shaojie, Tan, Qihua
• Format: Journal Article
• Language: English
• Published: Japan Blackwell Publishing Ltd 01-07-2013
• Subjects: Acids; Aged; aging; Aging - blood; anti-oxidants; China - epidemiology; Cognition & reasoning; Cognition - physiology; Cognition Disorders - blood; Cognition Disorders - epidemiology; Cognition Disorders - physiopathology; cognitive function; Cross-Sectional Studies; Disease Progression; Female; Follow-Up Studies; Geriatric Assessment - methods; hand grip strength; Humans; Incidence; Male; Middle Aged; Muscle Strength - physiology; Muscular system; Older people; Retrospective Studies; uric acid; Uric Acid - blood; China; China, People's Rep., Shandong Prov., Qingdao; cognitive function; aging; hand grip strength; uric acid; anti-oxidants
• ISSN: 1444-1586; 1447-0594
• DOI: 10.1111/j.1447-0594.2012.00962.x

Aim
Previous studies have shown that uric acid (UA) has strong anti‐oxidant properties, and that high circulating levels of UA are prospectively associated with improved muscle function and cognitive performances in elderly Caucasians. We carried out a replication study in elderly Chinese using cross‐sectional design.
Methods
Data from 2006 individuals aged 50–74 years who participated in a population‐based cross‐sectional survey in Qingdao, China, were analyzed. Hand grip strength was measured in kilograms by using an electronic dynamometer. The sit‐to‐stand (STS) test time was used to represent lower limb strength. The Mini‐Mental State Examination (MMSE) was used to estimate the participants' cognitive function. Lifestyle, comorbidities and laboratory measures were considered as potential confounders. Multiple linear regression models and binary logistic regression were fitted to find the association of UA with strength measures and cognitive performances.
Results
Participants were grouped according to UA tertiles (<257.75 mmol/L, ≥257.75 and ≤359.00 mmol/L, >359.00 mmol/L). Hand grip strength significantly increased across UA tertiles (26.4 ± 8.5 kg; 30.1 ± 10.5 kg; 35.0 ± 11.4 kg; P < 0.001), and prevalence of cognitive disorder declined across UA tertiles (7.9%, 4.9%, 3.1%; P = 0.012). After adjusting for potential confounders, high UA level remained significantly associated with high grip strength (P = 0.023) and decreased risk of cognitive disorder with an OR of 1.002 (95% CI 1.000–1.004; P = 0.022). However, UA level was not significantly associated with STS time (P = 0.780).
Conclusions
Our findings suggested that notwithstanding the associated increased risk of cardiovascular disease, UA might play a protective role in aging‐associated decline in muscle strength and cognitive function. Geriatr Gerontol Int 2013; 13: 672–677.