The association between gallstones and metabolic syndrome in urban Han Chinese: a longitudinal cohort study

Abstract

The precise association between metabolic syndrome (MetS) and gallstone disease remains unclear in China. This study aimed to clarify the relationship between MetS and gallstone and evaluate whether counts of metabolic abnormalities had influence on gallstone disease. We fitted gender-specific generalized estimating equation (GEE) regression models with data from a large-scale longitudinal study over 6-year follow-up to elucidate the real association. This study included 18291 participants with 3 times repeated measures at least who were free from a prior history of gallstone disease and cholecystectomy. A total of 873 cases of gallstones occurred during 6-year follow-up. The incidence density of gallstone in the group of subjects with MetS was higher than the group without MetS (10.27 vs 5.79). The GEE analyses confirmed and clarified the association between MetS and gallstone disease in males (RR = 1.33, P = 0.0020), while this association was not significant in females (RR = 1.15, P = 0.4962). With numbers of metabolic syndrome components increasing, the risk of gallstone disease showed corresponding increasing in males. In conclusion, the associations of MetS and gallstone are different in males and in females. And the risk of gallstone disease increases with the number of components of MetS for males but not for females.

Figure 1. Modeled cumulative incidence of gallstone disease from age 18 to 82, stratified by sex and MetS status.

The curves were modeled by real cumulative incidence of gallstone disease. Curves of cumulative incidence of gallstone disease among persons with MetS are in red; curves of cumulative incidence of gallstone disease among persons without MetS are in blue.

Figure 2. The distribution of participants for each repeated surveys at each year.

The participants had their first survey and entered our cohort in 2005, 2006, 2007 and 2008, separately. The total number of participants was 18291. The 1st survey represented the total number of participants to be involved in the subsequent surveys of the different years. The 2^nd survey represented the number of participants who had their second survey in each subsequent year. Similarly, the 3^rd survey, the 4^th survey, the 5^th survey and 6^th survey separately represented the number of participants who had their third survey, fourth survey, fifth survey and sixth survey. 18291 participants took the 1st survey and at least two of 2^nd–6^th surveys.