Serum uric acid and its correlates in Chinese adult populations, urban and rural, of Beijing. The PRC-USA Collaborative Study in Cardiovascular and Cardiopulmonary Epidemiology

Abstract

BACKGROUND: Reports on serum uric acid (SUA) levels in Chinese populations are sparse, but there is evidence that hyperuricaemia and gout are not uncommon. This paper characterizes SUA levels, their correlates, and their relationship to blood pressure (BP) and prevalent high blood pressure (HBP) for urban and rural adult population samples in north China. METHODS: In 1987-1988, a cross-sectional study was carried out, using standardized methods, on men and women aged 40.58 in a Beijing area urban steel mill (N = 2013) and on rural farms (1507). Main outcome measures were SUA, systolic and diastolic blood pressure (SBP, DBP), and prevalent HBP (SBP > or = 140 or DBP > or = 90 mmHg or receiving an antihypertensive drug). RESULTS: Mean SUA levels for men were 5.75 mg/dl in urban and 5.58 mg/dl in rural settings; for women, 4.67 and 4.48 mg/dl. Mean values were higher with age in women, but not in men. Age-standardized prevalence rates of HBP were significantly higher in upper SUA strata (men > or = 7.00, women > or = 6.00 mg/dl) than lower SUA strata both with and without inclusion of those on antihypertensive drugs. Mean SUA levels were correspondingly higher in hypertensive than non-hypertensive people. In multiple regression analyses, body mass index and serum triglycerides were strongly associated with SUA. Also SBP, DBP, and HBP were generally associated with SUA for the whole population sample, with smaller coefficients after excluding those on antihypertensive drugs. However, in these multivariate analyses the strength of the association was low order. CONCLUSION: In addition to its strong association with body mass index, SUA is independently related to serum lipids, particularly triglycerides, and to serum glucose. While some of the univariate relation of SUA to BP is apparently due to the strong relation of body mass to both SUA and BP, a low order significant relation between SUA and BP remains with control for BMI.