Thyroid Hormone Levels And Cardiometabolic Risk Factors In Hypertensive Adult Ghanaians
Metabolic syndrome can be found in approximately one-third of patients who do not have diabetes but have hypertension. There are numerous correlations between the metabolic syndrome and hypertension, although this is not always the case. As metabolic syndrome and thyroid dysfunction are independent risk factors for the same disease process, namely cardiovascular disease, it is possible that patients suffering from both these disease entities may have a compounded risk. Our study will therefore attempt to determine the prevalence of metabolic syndrome and investigate the proposed association between these two disease entities and identify the factors that increase the risk of this association. This cross-sectional study was conducted at the Hypertension Clinic of the Department of Medicine, Komfo Anokye Teaching Hospital (KATH), Kumasi between April 2010 and November 2010. A total of 300 participants comprising of 200 hypertensives and 100 normotensives were enrolled. The prevalence of MetS among the hypertensive patients were significantly higher than the normotensive control (56.5% vrs 9.0%, 54.5% vrs 5.0% and 65.5%vrs15.0%, p<0.001) using NCEP ATP III, WHO and IDF criteria respectively. Irrespective of the criteria applied, all the components of MetS were significantly higher among the hypertensive patients as compared to the normotensive control. Among the hypertensive patients, the highest prevalence of cardiovascular risk factor was abdominal obesity as measured by WHR (77.0%), followed by reduced HDL-cholesterol (74.0%). From the univariate analysis, females were at about 3 times at risk of developing hypertension as compared to the male counterpart (OR = 2.7; 95% CI = 1.6-4.4; p = 0.0000). Reduced apolipoprotein A1 served as a risk factor (aOR = 13.4; 95% CI = 1.5-121.4; p = 0.0210) whilst high apolipoprotein A1 protects the individual from developing hypertension (aOR = 0.1; 95% CI = 0.0-0.2; p = 0.0000). High apolipoprotein B poses about 9 times risk of developing hypertension as compared to the normal level (aOR = 9.3; 95% CI = 4.2-20.9; p = 0.0000). Both Impaired fasting glucose and diabetes each pose more than 10 times risk of developing hypertension as compared to normoglycaemia. fT4 levels were positively associated to BMI and Apo A1 after adjustment for age. fT4 levels were however negatively associated to TC (β= -0.275; p<0.05), LDL-C (β= -0.337; p<0.05) and FBG (-0.121; p<0.05). We also demonstrated that, low normal FT4 levels were significantly associated with three of the cardiovascular risk factors. These findings are consistent with an increased cardiovascular risk in subjects with low normal thyroid function. In conclusion, the study demonstrated that, hypertension is more than just elevated blood pressure; it is intimately associated with the metabolic syndrome. There is therefore the need for metabolic screening of all hypertensives and increase awareness creation on the critical importance of public health strategies aimed at reducing risk factors in the entire population. Early detection and treatment (Multi-target approach) of the global risk profile should thus become a priority.
A thesis submitted to the Department of Clinical Microbiology, School of Medical Sciences, Kwame Nkrumah University of Science and Technology, in partial fulfillment of the requirements for the degree of Master of Philosophy, May-2011