The association of higher levels of within-normal-limits liver enzymes and the prevalence of the metabolic syndrome

BACKGROUND: Metabolic syndrome (MetS) is frequently characterized by elevated liver enzymes, including gamma-glutamyl transferase (GGT) and alanine aminotransferase (ALT). Our objective was to evaluate the range of prevalence of MetS in apparently healthy individuals whose liver enzyme concentrations were all within-normal-range. METHODS: We have performed a cross sectional analysis on participants of the Tel-Aviv medical center inflammation survey (TAMCIS) recruited between the years 2003-2009. Analyzed were a cohort of 6,561 men and 3,389 women. RESULTS: The prevalence of MetS increased significantly from the first quintile to the fifth for both GGT and ALT, all the five quintiles being in the normal range. Logistic regression analysis for the presence of MetS showed crude odds ratios of 2.7 and 2.4 between the first and fourth quintiles and 3.6 and 3.2 for the fifth quintile in men and women respectively for ALT. For GGT the respective odds being 3.6 and 3.2 for the fourth quintile and 3.9 and 3.4 for the fifth quintile in men and women, respectively. CONCLUSIONS: A relatively high prevalence of MetS was noted in a cohort of apparently healthy individuals with liver enzyme concentrations within-normal-limits. Practical consequences include the need to follow up these enzyme concentrations as continuous variables and to take into consideration that even relatively small elevations within the normal range might reflect the presence of dysmetabolism.