Gamma‐glutamyltransferase, insulin resistance and cardiometabolic risk profile in a middle‐aged African population. (December 2014)

• Record Type: Journal Article
• Authors: Matsha, Tandi Edith; Macharia, Muiruri; Yako, Yandiswa Yolanda; Erasmus, Rajiv Timothy; Hassan, Mogamat Shafick; Kengne, Andre Pascal
• Is Part Of: European journal of preventive cardiology. Volume 21:Number 12(2014)
• Page Start: 1541
• Page End: 1548
• Publication Date: 2014-12
• Subjects: Gamma-glutamyltransferase -- insulin resistance -- metabolic syndrome -- cardiovascular risk -- South Africa; Cardiovascular system -- Diseases -- Prevention -- Periodicals; Cardiac patients -- Rehabilitation -- Periodicals; 616.12
• DOI: 10.1177/2047487313501967
• Languages: English
• ISSNs: 2047-4873

Abstract

Background: Mechanisms linking liver functions with cardiometabolic risk may involve insulin resistance (IR) and non‐alcoholic fatty liver disease. We assessed the associations of gamma‐glutamyltransferase (GGT) levels with IR and metabolic syndrome (MetS) in an adult South African urban cohort. Methods: 1198 participants aged >15 years (297 men) were drawn from the Bellville‐South suburb (Cape Town). The homeostatic model assessment of insulin (HOMA‐IR), β‐cells function (HOMA‐B%), fasting insulin resistance index (FIRI) and the quantitative insulin‐sensitivity check index (QUICKI) were calculated, and MetS defined according to the Join Interim Statement 2009 criteria. Associations of GGT levels with covariates were assessed on a continuous scale and across sex‐specific quarters of GGT, with adjustment for confounders via generalized linear and logistic regressions. Results: Indicators of IR (HOMA‐IR, FIRI and fasting insulin) increased, whereas those for insulin sensitivity (Sib and QUICKI) diminished significantly linearly and across increasing GGT quarters. In multivariable‐adjusted models, adjustment for sex, age, BMI, cigarette smoking and alcohol intake yielded the strongest, significant associations between GGT and all markers of IR/IS and glycemia excluding glucose insulin ratio. In a similar level of adjustments, with/without further adjustment for markers of IR/insulin sensitivity, the prevalence of MetS significantly increased across quarters of GGT. Conclusions: GGT levels were independently associated with insulin sensitivity and MetS in this population. Unaccounted, chronic elevation of GGT may therefore be a cue to screen and monitor individuals for MetS and diabetes, and may warrant consideration as an indicator of high risk for the development of these metabolic disorders.