<p>Specific higher levels of serum uric acid might have a protective effect on bone mineral density within a Chinese population over 60 years old: a cross-sectional study from northeast China</p>

Abstract

Background and objective: Oxidative stress has been demonstrated to be a mechanism that leads to bone mass reduction, and according to many studies, serum uric acid (UA) is a strong endogenous antioxidant that can protect bone mineral density (BMD). To date, there have been no large-scale, cross-sectional studies based on the population in northeast China to assess the relationship between serum UA and BMD. Therefore, we examined the association between serum UA and BMD among a Chinese population older than 60 years old in northeast China. Methods: This research was a cross-sectional study of 3465 Chinese individuals over 60 years old in nine communities from the city of Shenyang, which is the capital of northeast China’s Liaoning Province. Participants were stratified into three groups by serum UA or BMD levels, and then Pearson’s correlation analysis and multiple regression analysis were used to study the relationship between serum UA and BMD. Results: We found that participants with higher serum UA levels had significantly greater BMD and T-values compared to those of participants with lower serum UA levels. After adjusting for confounding factors, Pearson’s correlation analysis and multiple regression analysis showed that higher serum UA levels remained associated with higher BMD levels ( P <0.05). In different models, the prevalence of osteoporosis (OP) among participants with higher serum UA levels was reduced by 23% to 26% ( P <0.05) compared to that in individuals with lower serum UA levels. In addition, serum UA levels were negatively correlated with estimated glomerular filtration rate (eGFR) and positively correlated with 25-hydroxy vitamin D 3 [25-(OH)D 3 ] ( P <0.05). Conclusion: We concluded that higher serum UA levels are associated with greater BMD, and serum UA might have a protective effect on bone metabolism due to its antioxidant properties.

No association between serum uric acid and lumbar spine bone mineral density in US adult males: a cross sectional study

“…However, observational data on the relationship of SUA with lumbar spine BMD have been mixed. Four Chinese cross-sectional studies that included postmenopausal women and older adults revealed a positive association of a higher SUA with greater BMD 19 , 33 – 35 , with similar findings among other studies from Asia 13 , 14 , 36 , 37 . In contrast, another Chinese cross-sectional study showed a positive association of SUA with lumbar spine BMD only in postmenopausal women (n = 4256), rather than in men (n = 943) 20 .…”

The Association between Serum Uric Acid and Bone Mineral Density in Older Adults

“…Currently, clinical studies regarding the relationship between sUA and BMD among older adults are limited and controversial. Four cross-sectional studies from China reported a positive correlation between a higher sUA and greater BMD among postmenopausal women and older adults [ 19 – 22 ]. This conclusion was supported by other studies from Asia [ 23 – 25 ], as well as from the Netherlands and Italy [ 26 , 27 ].…”

Analyses of the relationship between hyperuricemia and osteoporosis

“…Most previous studies analyzed the association between serum uric acid levels and BMD rather than evaluating the association between hyperuricemia and osteoporosis. In recent studies, the categories of serum uric acid were not described 7 , 26 , 35 , and the authors divided participants according to their median serum uric acid level 11 , tertiles 8 , quantiles 15 , 20 or quintiles 10 . Few studies have included subgroups with serum uric acid levels > 7 mg/dL, indicating hyperuricemia 9 , 10 , but the subgroup was as small as 25/1080 9 and the participants were limited to men aged 40 to 60 years 10 .…”

“…Although previous studies support a protective role for uric acid in bone metabolism disorders, the majority of the studies were conducted in a single institution 10 , 26 , restricted to a single sex 14 , limited to old participants 8 , 9 or the sample sizes were small 7 , 11 . No study stratified the groups by sex and age, and no study performed subgroup analyses according to past medical histories.…”