[Metabolic syndrome components and renal cell cancer risk in Chinese males: a population-based prospective study]

Objective: To investigate the association between metabolic syndrome (MS) components and renal cell cancer in Chinese males. Methods: All male employees and retirees of the Kailuan Group were recruited in the Chinese Kailuan Male Cohort Study. They had been experienced routine physical examinations ever two years since May 2006. A total of 104 274 males were prospectively observed by 31 December 2015. Information on demographics, height, weight, blood glucose, blood lipid, blood pressure, as well as the information of incident renal cell cancer cases were collected at the baseline investigation by questionnaire, physical measurement and laboratory test. Cox proportional hazards regression models were used to evaluate the association between baseline MS and MS components (body mass index, blood glucose, blood lipid, blood pressure) and the risk of renal cell cancer in males. Results: A total of 104 274 males were recruited in our study with a age of (51.21±13.46) years, with 823 892.96 person-years follow-up and the median follow-up time was 8.88 years. A total of 131 new renal cell cancer cases were identified in the Kailuan male cohort study, and the crude incidence density was 15.90 per 100,000 person-years. Compared with no MS, the hazard ratios (HR) (95% CI) of MS was 1.97 (1.32-2.94).When compared with normal level, the HR (95%CI) of obesity or overweight, hypertension, and dyslipidemia was 1.49 (1.04-2.14), 1.56 (1.06-2.29), and 1.77(1.23-2.54), after adjusting for potential confounding factors (i.e., age, education, income, smoke, and alcohol drink), respectively. In addition, a statistically significant trend (P for trend<0.001) of increased renal cell cancer risk with an increasing number of abnormal MS components was observed. Conclusion: Obesity or overweight, hypertension, dyslipidemia and MS may increase the risk of renal cell cancer for Chinese males.