Fasting glycemia and glycated hemoglobin categories: Relationship to serum lipoprotein(a) level and disparity in 2 geographic regional groups of TurkeyAltan Onat1, Yusuf Karadeniz4, Günay Can2, Süleyman Karakoyun5, Fatma Özpamuk Karadeniz6, Ayşem Kaya3, Hüsniye Yüksel1
1Departments of Cardiology, Institute of Cardiology, İstanbul University; İstanbul-Turkey
2Public Health, Cerrahpaşa Faculty of Medicine, Institute of Cardiology, İstanbul University; İstanbul-Turkey
3Biochemistry Section, Institute of Cardiology, İstanbul University; İstanbul-Turkey
4Department of Medicine, Mehmet Akif İnan Training and Research Hospital; Şanlıurfa-Turkey
5Department of Cardiology, Faculty of Medicine, Kafkas University; Kars-Turkey
6Department of Cardiology, Balıklıgöl State Hospital; Şanlıurfa-Turkey
Objective: The goal of the present study was to determine covariates of serum lipoprotein (Lp) (a) within fasting glucose and glycated hemoglobin (HbA1c) categories, and to detect features that were different among covariates based on residence in Marmara and Central Anatolia (Marm-CA) regions or remaining 5 geographic regions of Turkey.Keywords: apolipoprotein B; autoimmune activation; impaired fasting glucose; insulin resistance; lipoprotein(a); prediabetes
Methods: Data of randomly-selected group of 1167 men and women (mean age 61 years) who participated in biennial surveys of 2013 and 2015 were cross-sectionally analyzed in 6 categories.
Results: In multiple linear regression analysis of nondiabetic women, homeostatic model assessment (HOMA) index score was inversely associated with Lp(a) (β coefficient 0.49; p=0.001); this was not true for men. In the whole sample, Lp(a) was significantly positively associated with female sex and with serum creatinine, and inversely in each sex with HOMA index (β coefficient 0.63; p<0.001). Linear models within separate categories showed significant associations of Lp(a) only in individuals with no evidence of diabetes other than HbA1c >6.5%: in women, positive association with total cholesterol and inverse relationship with creatinine were found, and in men, positive association with apolipoprotein (apo) B was determined. Similar age, diastolic blood pressure, fasting glucose, triglyceride, uric acid, and C-reactive protein values were obtained from participants of 2 regional groups. Residents of the Marm-CA region who were nondiabetic exhibited significantly (by 23%) lower serum Lp(a) among individuals with HbA1c ≥5.7%, significantly higher HOMA index score, concentrations of apoB, and low-density lipoprotein cholesterol.
Conclusion: Hallmark of prediabetic and diabetic glycemia/HbA1c categories seems to be an independent inverse association between Lp(a) protein (yet not of apoB) and HOMA score, this being primarily so in residents of Marm-CA region. (Anatol J Cardiol 2016; 16: 000-00)
Corresponding Author: Altan Onat, Türkiye