title: Three-year's changes in glucose tolerance status in the Bellville South cohort: rates and phenotypes associated with progression.
abstract: OBJECTIVE
  To determine the phenotypes associated with progression to type 2 diabetes or worsening in glucose tolerance during a 3-year follow-up of a community-based cohort in Cape Town, South Africa.
  
  
  METHODS
  A total of 198 eligible subjects (72.3% women) aged 55.2 years, from the Bellville-South community were followed-up between 2008 and 2011. Baseline and follow-up data collections included glucose tolerance status, anthropometric, blood pressure, lipids, insulin, γ-glutamyltransferase, cotinine, creatinine and HbA1c. Progression in glucose tolerance status at 3-year was the composite of new-onset diabetes and any worsening in glucose tolerance status.
  
  
  RESULTS
  The cumulative incidence of progression in glucose tolerance status was: 16.2% (32 participants including 11 with new-onset diabetes), and increased in a stepwise fashion with the number of components of metabolic syndrome (MetS). In age and sex-adjusted logistic regression analyses, MetS [odd ratio: 3.08 (95% CI: 1.34-7.10)], HbA1c [5.26 (1.94-14.24)], HDL-cholesterol [0.05 (0.01-0.33)], γ-glutamyltransferase [1.99 (1.07-3.67)], triglycerides [1.71 (1.13-2.58)] and total/HDL-cholesterol [1.45 (1.08-1.93)] were significant predictors of progression, while borderline effects were observed for baseline glucose and diastolic blood pressure. Markers of adiposity were mostly stable or improved among non-progressors during follow-up, but deteriorated significantly among progressors, resulting in significant statistical interactions.
  
  
  CONCLUSIONS
  High rates of deterioration of glucose status over time were found in our population, with nearly one-fifth of them acquiring a glucose tolerance worse status within a very short follow-up. Our study extends to this setting the well-known utility of phenotypes of MetS single or in combination, in predicting worsening in glucose tolerance status.
authors.affiliation: Department of Biomedical Sciences, Faculty of Health and Wellness Science, Cape Peninsula University of Technology, Cape Town, South Africa.
authors.forename: T E
authors.initials: TE
authors.lastname: Matsha
authors.forename: D J
authors.initials: DJ
authors.lastname: Soita
authors.forename: M S
authors.initials: MS
authors.lastname: Hassan
authors.forename: G M
authors.initials: GM
authors.lastname: Hon
authors.forename: Y Y
authors.initials: YY
authors.lastname: Yako
authors.forename: A P
authors.initials: AP
authors.lastname: Kengne
authors.forename: R T
authors.initials: RT
authors.lastname: Erasmus
mesh_terms: D003920:Diabetes Mellitus / Q000453:epidemiology*; D005260:Female; D018149:Glucose Intolerance / Q000453:epidemiology; D006801:Humans; D024821:Metabolic Syndrome / Q000453:epidemiology; D008875:Middle Aged; D012307:Risk Factors; D013019:South Africa / Q000453:epidemiology