Comparison of clinical and biochemical variables in type 2 diabetes mellitus patients and their first-degree relatives with metabolic syndrome in Benin City, Nigeria: A cross sectional case controlled study.

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is characterized by a relative insulin deficiency or insulin resistance. It is also associated with a cluster of metabolic abnormalities, including hyper-tension and dyslipidemia. Although there are many studies that have studied the metabolic abnormalities in T2DM patients with metabolic syndrome (MetS), only few of them have assessed the metabolic abnormalities in their first-degree relatives (FDRs) who had MetS. The aim of this study is to compare the clinical and biochemical variables in T2DM subjects and their FDRs without diabetes in Benin City, Nigeria.

METHODS: This is a cross sectional case control study including 124 T2DM patients, 96 FDR of T2DM subjects, and 96 controls recruited using convenience sampling. Data were collected using a questionnaire-administered technique. Variables of interest that were assessed included anthropometric indices like waist circumference (WC), hip circumference (HC), waist:hip ratio (WHR), body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), serum lipid profile, fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), proteinuria, and microalbuminuria. The 1999 World Health Organization (WHO) criteria were used to make a diagnosis of metabolic syndrome. The Chi-square test was used for comparison of proportions. P-value of less than 0.05 was taken as statistically significant. The student t-test was used to compare means and test for significant differences in the anthropometric and the metabolic indices.

RESULTS: The prevalence of the MetS in T2DM persons was 87.1%, 16.7% in the FDR group, and 13.5% in the control group according to the WHO criteria. The mean value of HbA1c was significantly higher in T2DM subjects with MetS (p<0.05). The mean values of WC, FPG, total cholesterol, HDL cholesterol, and LDL cholesterol were higher in subjects with MetS in the T2DM group than in persons with MetS in the FDR group though not significant (p>0.05). The mean values of WHR, BMI, SBP, DBP, and triglyceride were higher in persons with the MetS in the FDR group than in persons with the MetS in the T2DM group. The difference in the BMI and SBP was significant (p<0.05).

CONCLUSION: The prevalence of MetS in subjects with T2DM in Nigeria is very high. Though, all the biochemical and clinical indices were higher in T2DM subjects with MetS, the mean HbA1c, BMI, and SBP was significantly higher when compared to their FDR who also have MetS.