The association of sex with cardiometabolic disease risk in Ghana

BACKGROUND AND AIMS. Cardiometabolic diseases are the principal causes of death and disability globally. This is believed to be as a consequence of globalization which has influenced lifestyles leading to consumption of more energy dense-nutrient poor foods and people being less physically active. Health inequalities between males and females have become common in the midst of this situation and women tend to be the most affected, especially in low- and middle- income countries. There is a need to broaden our understanding on risk factors for cardiometabolic diseases and how they vary by sex in Ghana. This thesis aims to fill this research gap by (1) systematically reviewing studies looking at sex differences associated with cardiometabolic disease risk in Ghana; (2) assessing the magnitude of sex differences regarding overweight/obesity prevalence and associated contributing health factors (for this the Ghana Demographic Health Survey 2014 was used); and (3) investigating sex differences in risk factors for cardiometabolic disease in Ghana with specific reference to a case study focused on young adults, from the Greater Accra region.

METHODS. A systematic review was conducted to look at sex differences associated with cardiometabolic disease risk in Ghana. The Ghana Demographic Health Survey (2014) was used (3913 = females and 3871= males) to establish the magnitude of sex differences in overweight and obesity. Logistic regression modelling was used to establish how these sex differences are associated with other socio-demographic factors including sex of household member, type of place of residence, age of household members, wealth index and level of education. Biological, lifestyle, anthropometric, demographic and socioeconomic data were used from 117 participants male (55) and female (62) participants aged 18-35-years old from urban areas of Accra to establish relationships between sex, lifestyle variables and risk for cardiometabolic diseases including hypertension, blood glucose, and obesity, using logistic and linear regression modelling.

RESULTS. Fifty (50) relevant studies were selected for review that included risk factors for obesity, T2DM, hypertension, and both diseases combined, as well as related cardiometabolic conditions. Thirty three of the fifty studies made comparisons between males and females and showed that females were more prone to the various risk factors (BMI, central obesity, physical inactivity Low HDL, High LDL High triglyceride and total cholesterol), with the exception of hypertension. These put them at a higher risk for cardiometabolic diseases and their consequences. The DHS 2014 data revealed that sex differences in Body-Mass-Index (BMI) for rural (X2 = 282.9, p < 0.001) and urban residents (X2 = 331.8, p < 0.001) respectively were significant with females more likely to be overweight or obese. Across all wealth quintiles, there were more overweight and obese women and more underweight men, with the exception of the rural rich where there were more underweight females than males. For the case study, males recorded a higher mean systolic blood pressure of 117.8 mmHg ± 13.58 compared to females 109.3 mmHg ± 9.9 (P < 0.01) and were more likely to be pre-hypertensive or hypertensive. More females 21 (33.9%) than males 4 (7.3%) had central obesity. More females 45.2% than males 29.1% fell into the overweight/obese category. For dietary intake, more women 25 (40.3 %) than men 14 (25.5) were in the high intake group of globalised food. There was a significant sex difference in moderate to vigorous physical activity (MVPA) (t = 7.352 p = < 0.001) and total time in physical activity (t = 2.726 p = 0.008).

CONCLUSIONS. This thesis has highlighted the sex inequalities in risk factors for cardiometabolic disease in Ghana, which largely identify females as being at greater risk than males. Some epidemiological studies include sex in their research as a descriptive variable, but few analyse sex differences as their primary focus of the research. The findings presented here suggest that sex needs to be given more attention in studies of cardiometabolic disease in Africa if the sustainable development goals related to health and well-being are to be achieved with equality in the region.