Prevalence and Risk Factors of Hyperuricemia Among Young and Middle-Aged Tibetan Men Living at Ultrahigh Altitudes: A Cross-Sectional Study

Background: Few studies have examined the prevalence or risk factors of hyperuricemia among populations living at ultrahigh altitudes. Here we examined the prevalence of hyperuricemia and factors associated with it among young and middle-aged Tibetan men living at ultrahigh altitudes. Methods: This cross-sectional study analyzed 672 Tibetan men 18-60 years old living on the Qinghai-Tibet Plateau (mean altitude 4,014m) within the county of Litang in the Ganzi Tibetan autonomous prefecture of Sichuan Province, China. Demographic and clinical data were collected from self-administered questionnaires, physical examinations and laboratory tests. Participants whose blood uric acid (UA) contained >420 mu mol/l were classified as having hyperuricemia. Results: Of the 672 men analyzed, 332 (49.4%) had hyperuricemia. Multivariate logistic regression showed risk of hyperuricemia to correlate positively with body mass index (per 1U increase: odds ratio [OR] 1.172, 95% confidence interval [CI] 1.1066-1.243), triglycerides (OR 1.408, 95% CI 1.084-1.828), red blood cell count (OR 1.376, 95% CI 1.009-1.875), and creatinine level (per 1U increase: OR 1.051, 95% CI 1.033-1.070). Conversely, risk of hyperuricemia correlated negatively with the presence of diabetes mellitus (OR 0.412, 95% CI 0.175-0.968). Subgroup analyses showed that prevalence of hyperuricemia was significantly higher among those with polycythemia than among those without it, and that UA levels correlated positively with hematocrit and hemoglobin levels. Conclusions: Hyperuricemia is an important public health problem among Tibetan men living at ultrahigh altitudes in Ganzi autonomous prefecture. The region urgently requires appropriate prevention and management efforts.