Abstract :
Background: Sarcopenia may be related to increases in reactive oxygen species formation and
inflammation, both of which are associated with elevations in serum uric acid. Objective: To test the hypothesis
that a reduced skeletal muscle mass index, indicative of sarcopenia, is related to elevations in uric acid.
Design: Cross-sectional analysis of nationally representative data. Setting: Third National Health and Nutrition
Examination Survey, 1988-1994. Patients: 7544 men and women 40 years of age and older who had uric acid,
skeletal muscle mass, and select covariate information. Measurements: Skeletal muscle mass assessment was
based on a previously published equation including height, BIA-resistance, gender, and age. Absolute skeletal
muscle mass was calculated for all study population individuals and compared against the sex-specific mean for
younger adults. Serum uric acid data were gathered from the NHANES laboratory file. Results: A logistic
regression analysis revealed that elevations in serum uric acid are significantly related to sarcopenia status. For
every unit (mg/dL) increase in uric acid, the odds ratio of manifesting a skeletal muscle mass index at least one
standard deviation below the reference mean was 1.12. Participants in the highest grouping (>8 mg/dL) of serum
uric acid concentration had 2.0 times the odds of manifesting sarcopenia compared to the lowest grouping (<6
mg/dL) (p<0.01) after adjusting for the additional covariates. Limitations: This study design was limited in its
cross-sectional nature. Potential selection, measurement, and recall bias may have occurred, and methodology
used to classify sarcopenia status based on skeletal muscle mass index is not validated. Conclusion: This
observation provides support for the theory that elevations in uric acid may lead to sarcopenia, although the
proposed mechanism needs further experimental support.
Keywords :
reactive oxygen species , uric acid , sarcopenia , NHANES III , aging
