Browsing by Author "Motala, Ayesha A."

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    Burden of diabetes and first evidence for the utility of HbA1c for diagnosis and detection of diabetes in urban Black South Africans : the Durban diabetes study
    (Public Library of Science, 2016) Hird, Thomas R.; Pirie, Fraser J.; Esterhuizen, Tonya M.; O’Leary, Brian; McCarthy, Mark I.; Young, Elizabeth H.; Sandhu, Manjinder S.; Motala, Ayesha A.
    Objective: Glycated haemoglobin (HbA1c) is recommended as an additional tool to glucose-based measures (fasting plasma glucose [FPG] and 2-hour plasma glucose [2PG] during oral glucose tolerance test [OGTT]) for the diagnosis of diabetes; however, its use in sub-Saharan African populations is not established. We assessed prevalence estimates and the diagnosis and detection of diabetes based on OGTT, FPG, and HbA1c in an urban black South African population. Research Design and Methods: We conducted a population-based cross-sectional survey using multistage cluster sampling of adults aged ≥18 years in Durban (eThekwini municipality), KwaZulu-Natal. All participants had a 75-g OGTT and HbA1c measurements. Receiver operating characteristic (ROC) analysis was used to assess the overall diagnostic accuracy of HbA1c, using OGTT as the reference, and to determine optimal HbA1c cut-offs. Results: Among 1190 participants (851 women, 92.6% response rate), the age-standardised prevalence of diabetes was 12.9% based on OGTT, 11.9% based on FPG, and 13.1% based on HbA1c. In participants without a previous history of diabetes (n = 1077), using OGTT as the reference, an HbA1c ≥48 mmol/mol (6.5%) detected diabetes with 70.3% sensitivity (95%CI 52.7–87.8) and 98.7% specificity (95%CI 97.9–99.4) (AUC 0.94 [95%CI 0.89–1.00]). Additional analyses suggested the optimal HbA1c cut-off for detection of diabetes in this population was 42 mmol/mol (6.0%) (sensitivity 89.2% [95%CI 78.6–99.8], specificity 92.0% [95%CI: 90.3–93.7]). Conclusions: In an urban black South African population, we found a high prevalence of diabetes and provide the first evidence for the utility of HbA1c for the diagnosis and detection of diabetes in black Africans in sub-Saharan Africa.
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    High prevalence of cardiovascular risk factors in Durban South African Indians : the Phoenix Lifestyle Project
    (Health & Medical Publishing Group, 2016-02) Prakaschandra, Dorcas Rosaley; Esterhuizen, Tonya M.; Motala, Ayesha A.; Gathiram, Prem; Naidoo, Datshana Prakesh
    Background. Previous studies show a high prevalence of cardiovascular (CV) risk factors in South African (SA) Asian Indians, with the emergence of premature coronary artery disease in young Indian subjects. Objective. To determine the prevalence of CV risk factors in this population. Methods. This was a cross-sectional study of randomly selected adults aged 15 - 64 years from the suburb of Phoenix in Durban, KwaZulu-Natal Province, SA. All participants had demographic, anthropometric and biochemical measurements using the modified World Health Organization (WHO) STEPwise survey methods. Hypertension, obesity, lipid abnormalities and diabetes mellitus (DM) were diagnosed using WHO criteria. Age-standardised frequencies for glycaemic indices were calculated according to the WHO standard world population distribution. Results. Of the 1 428 subjects who responded (response rate 72.1%), complete data for analysis were available on 1 378 (1 001 women). The mean age was 45.5 (standard deviation 13) years. There were high prevalences of hypertension (47.5%), DM (20.1%), total body obesity (raised body mass index) (32.4%) and increased waist circumference (73.1%). The ‘thin-fat’ Asian phenotype (isolated abdominal obesity) was found in only 4.8% of participants. High prevalences of total body obesity (32.1%), increased waist circumference (31.3%) and insulin resistance (28.2%) were documented in the youngest age group. Over half of the males and 14.6% of females were current smokers. Diabetic dyslipidaemia was found in 61 subjects (4.4%). In multivariate analysis, age, triglycerides and waist circumference measurement were significant independent risk factors associated with DM and, together with fasting glucose, also predicted hypertension. Conclusion. Compared with Asian Indian subjects with similar environmental exposure in previous studies, the magnitude of change in risk factor prevalence over the past two decades has been of epidemic proportions.