Significant Differences in the Prevalence of Elevated HbA1c Levels for Type I and Type II Diabetics Attending the Parirenyatwa Diabetic Clinic in Harare, Zimbabwe
Diabetics have chronically elevated glucose levels. High levels of glucose result in nonenzymatic formation of glycosylated haemoglobin (HbA1c). Therefore, elevated HbA1c is a good indicator of poorly controlled diabetes. We used the standard HbA1c method to determine glycemic control in diabetics attending a public health facility in Harare, Zimbabwe. Our study sought to assess the prevalence of elevated HbA1c amongst treated diabetics and compare the HbA1c levels by type of diabetes. The cross-sectional study was carried out at one of the main public health centres in Zimbabwe: the Parirenyatwa Group of Hospitals in Harare. Type I and type II diabetics were recruited and had their blood HbA1c levels measured. The standard one tailed proportion z test was used to test the hypothesis at 5% significance level. Combined prevalence of type I and type II diabetics with elevated HbA1c was 27%. There was no significant difference in levels of HbA1c by age and sex. Over half (54%) of Type I diabetics had elevated HbA1c, suggesting poor glycemic control. In contrast only 24% of the Type II diabetics studied had elevated HbA1c. The difference in proportion of Type I and Type II diabetics with elevated HbA1c suggestive of poor glycemic control was significant ( ). 1. Introduction According to the World Health Organization (WHO) diabetes mellitus is a state of chronic hyperglycaemia due to genetic and environmental factors. In Type 1 diabetes mellitus there is no production of insulin whereas in Type 2 diabetes mellitus there is insufficient insulin or cells do not respond to insulin present in the body (insulin resistance). The most frequent form is Type 2 diabetes (80% of cases) whilst Type 1 diabetes accounts for 10% of cases and specific diabetes such as gestational diabetes accounts for 5% of cases [1, 2]. In 2004 it was estimated that up to 3.4 million people died from diabetes and 80% of these deaths occurred in low and middle income countries such as Zimbabwe [3–5]. Half of the people who died as a result of diabetes were under the age of 70, 55% of them women [3–5]. Diabetes mellitus was generally considered to be a rare condition in Africa before the 1990s. Evidence of increased incidence and prevalence of type 2 diabetes mellitus was provided by some epidemiological studies carried out in that decade [5–7]. Africa is experiencing a demographic and epidemiological transition with a rise in diseases like diabetes mellitus. Most reports published between 1959 and 1985 indicated a prevalence of diabetes below 1.4% with the exception of those from South
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