Abstract
Objective: We assessed the relations of uric acid and urinary pH to metabolic syndrome (MetS) and its defining factors in a health screening population. Subjects and Methods: A total of 225,826 participants (168,042 men and 57,784 women) undergoing annual medical check-ups over 21 years from 1985 to 2005 at Toranomon Health Management Center were investigated to determine the relation ship of uric acid or urinary pH to MetS. MetS was defined according to the Japanese criteria, excluding waist circumference as the parameter of abdominal obesity; we had no data on waist circumference, so the BMI was used instead in this study. Results: Over the 21 years, elevation of the uric acid level occurred and the urinary pH decreased annually, while the prevalence of MetS increased annually. Urinary pH and uric acid were both related to most of the factors defining MetS, such as hypertension, fasting plasma glucose, BMI, hypertriglyceridemia, and a low HDL-cholesterol level, and were also related significantly to disease prevalence. During the follow-up of subjects with a normal BMI at the first medical check-up, the prevalence of MetS was significantly higher in the group with a uric acid level over 7.1 mg/dl or aciduria (urinary pH< 5.5). Conclusion: The results suggest that both uric acid and urinary pH are significant predictors of metabolic syndrome.
