An inverted J-shaped association of serum uric acid with muscle strength among Japanese adult men: a cross-sectional study

Abstract

BackgroundUric acid (UA) may protect muscle function from oxidative damage due to reactive oxygen species through its powerful antioxidant capacity. However, several studies have demonstrated that hyperuricemia is closely related to systemic inflammation and has oxidant properties effects, both of which may increase the risk of muscle strength loss. The purpose of this study was to examine the association of serum UA concentration with grip strength and leg extension power in adult men.MethodsThis study is a cross-sectional survey in which 630 Japanese male employees aged 30 years and older participated. Five hundred and eighty-six subjects participated in the measurement of grip strength, and 355 subjects participated in the measurement of leg extension power. Blood samples were obtained for serum UA analysis.ResultsAfter adjustment for potential confounders, grip strength differed significantly between participants with and those without hyperuricemia (geometric mean and 95% confidence interval [CI]: 40.3 [39.2–41.3] kg vs. 41.9 [41.3–42.5] kg; P = 0.01). In addition, serum UA levels (quartiles) showed an inverted J-shaped curve with grip strength (mean and 95% CI: Q1, 41.6 [40.6–42.6] kg; Q2, 42.2 [41.2–43.2] kg; Q3, 41.8 [40.8–42.8] kg; Q4, 40.4 [39.3–41.4] kg; P for quadratic trend = 0.05). The results in the leg extension power group were similar to those observed in the grip strength group.ConclusionThis population-based cross-sectional study shows for the first time that hyperuricemia is associated with poor muscle strength. Moreover, the results indicate an inverted J-shaped association between serum UA quartiles and muscle strength.

Characteristics of hyperuricemia in older adults in China and possible associations with sarcopenia

“…A number of previous studies have investigated the relationship between uric acid levels and the 3 components of sarcopenia, but this is the first study to examine the 3 components (muscle mass, muscle strength, and physical performance) and the age‐related parameter, bone mineral density, in the same population. Of the 3 sarcopenia components, the correlation of uric acid to muscle mass was the strongest, for it was retained in some comparisons when uric acid quartiles were examined in both men and women, while the correlation to handgrip was only retained in one quartile comparison in men.…”

“…Previous studies have reported that increased hyperuricemia both increased and decreased muscle strength as estimated by the handgrip test. One study has associated hyperuricemia with a decrease in skeletal muscle mass .…”

Chronic effects of aerobic and resistance exercise on cardio-metabolic profile in healthy nonobese subjects

“…[17,18] On the other hand, few workers have shown hyperuricemia to be associated with poor muscle strength. [19] UA was found to be significantly low in elite endurance athletes in comparison to sedentary controls. [3] Normal UA and urea levels with raised creatinine by aerobic exercises as observed in our study, rule out the presence of chronic kidney disease.…”

Relationship Between Arthritis And Muscular Strength In Older Women With Symptoms Of Sarcopenia

“…Although, that study did not show grip strength scores being affected by gout status, another study conducted by Huang, C, et al (2013), showed the opposite. They found that participants with hyperuricemia (associated with gout) had lower grip strength scores than those without hyperuricemia (40.3 kg, 95% CI:39.2-41.3 kg versus 41.9kg, 95% CI:41.3-42.5 kg, P=0.01) and concluded that hyperuricemia is associated with poor muscle strength.…”

“…Older adults account for 49.6% of the 54.4 million adults diagnosed and arthritis was more prevalent in women than men [24]. Arthritis also leads to pain as well as poor physical functioning in the affected joint(s) and can make various physical assessments difficult, including evaluations in grip strength [27][28][29][30][31][32] and gait speed [31,32]. Additionally, arthritis has been shown to be associated with decreases in lean mass [31,33].…”