ABSTRACT
AIM: To investigate whether impaired fasting glucose (IFG) confers cardiovascular risk. METHODS: A non-diabetic population-based sample representative of middle-aged and elderly Turks was studied at 8.5 years' follow-up for incident diabetes and coronary heart disease (CHD). Metabolic syndrome (MetS) was defined by ATP-III criteria modified for male abdominal obesity, and IFG and type 2 diabetes were identified by criteria of the American Diabetes Association. Stratification by presence of MetS was used. Outcomes were predicted providing estimates for hazard ratio (HR) obtained by use of Cox proportional hazards regression analysis in models that controlled for potential confounders. RESULTS: In 3181 adults (aged 52 ± 11.5 years at baseline), analysis stratified by MetS, gender and IFG status distinguished normoglycemic subjects by a "hypertriglyceridemic waist" phenotype consisting of significantly higher waist circumference, fasting triglyceride and lower high-density lipoprotein-cholesterol, regardless of gender and MetS. Additionally, lipoprotein (Lp) (a) tended to be lower in (especially female) participants with MetS. Multivariable linear regression in a subset of the sample demonstrated decreased Lp (a) levels to be associated with increased fasting glucose and insulin concentrations, again particularly in women. In Cox regression analysis, compared with normoglycemia, baseline IFG adjusted for major confounders significantly predicted incident diabetes at a 3-fold HR in men and only women with MetS. Cox models for developing CHD in 339 individuals, adjusted for conventional risk factors, revealed that IFG status protected against CHD risk [HR = 0.37 (95%CI: 0.14-0.998)] in subjects free of MetS, a protection that attenuated partly in male and fully in female participants with MetS. CONCLUSION: IFG status in non-diabetic people without MetS displays reduced future CHD risk, yet is modulated by MetS, likely due to autoimmune activation linked to serum Lp (a).
ABSTRACT
OBJECTIVES: We aimed to analyze 1) overall and coronary mortality findings in the Turkish Adult Risk Factor (TARF) study survey 2012 and 2) the temporal trends in prevalence of metabolic syndrome (MetS) and its distribution across seven geographic regions. STUDY DESIGN: Information on the mode of death was obtained from first-degree relatives and/or health personnel of a local health office. Information collected in survivors was based on history, physical examination of the cardiovascular system and Minnesota coding of resting electrocardiograms. RESULTS: Of 1527 participants to be surveyed, 796 were examined; information was obtained on the health status in 502 subjects, and death was ascertained in 56 participants. Thirty deaths were attributed to coronary and cerebrovascular disease. Cumulative 22-year evaluation of participants in the age bracket 45-74 years revealed coronary mortality to be high, with 7.6 per 1000 person-years in men and 3.8 in women. Data used from 1754 identical subjects (median age 46 years initially), and examined in two periods 12 years apart, indicated an increase in the prevalence of MetS by 1.3% per aging of 1 year. Analysis across geographic regions showed a rise in the prevalence in the Mediterranean region, already having highest prevalence along with Southeast Anatolia, while the prevalence declined in the Marmara region and persisted to be lowest in the Aegean region. CONCLUSION: The prevalence of MetS in Turkish adults aged 40 years or over, currently standing at 53%, shows significant differences across geographic regions, being highest in the two southern regions and lowest in the Aegean region.
