The Prevalence of Metabolic Syndrome and Determination of the Optimal Waist Circumference Cutoff Points in a Rural South African Community

Abstract

OBJECTIVETo determine the prevalence of metabolic syndrome and to define optimal ethnic-specific waist-circumference cutoff points in a rural South African black community.RESEARCH DESIGN AND METHODSThis was a cross-sectional survey conducted by random-cluster sampling of adults aged >15 years. Participants had demographic, anthropometric, and biochemical measurements taken, including a 75-g oral glucose tolerance test. Metabolic syndrome was defined using the 2009 Joint Interim Statement (JIS) definition.RESULTSOf 947 subjects (758 women) studied, the age-adjusted prevalence of metabolic syndrome was 22.1%, with a higher prevalence in women (25.0%) than in men (10.5%). Peak prevalence was in the oldest age-group (≥65 years) in women (44.2%) and in the 45- to 54-year age-group in men (25.0%). The optimal waist circumference cutoff point to predict the presence of at least two other components of the metabolic syndrome was 86 cm for men and 92 cm for women. The crude prevalence of metabolic syndrome was higher with the JIS definition (26.5%) than with the International Diabetes Federation (IDF) (23.3%) or the modified Third Report of the National Cholesterol Education Program Adult Treatment Panel (ATPIII) (18.5%) criteria; there was very good agreement with the IDF definition (κ = 0.90 [95% CI 0.87–0.94]) and good concordance with ATPIII criteria (0.77 [0.72–0.82]).CONCLUSIONSThere is a high prevalence of metabolic syndrome, especially in women, suggesting that this community, unlike other rural communities in Africa, already has entered the epidemic of metabolic syndrome. Waist circumference cutoff points differ from those currently recommended for Africans.

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“…In addition, older African women revealed the highest cotinine levels, which could imply that smoking was being used as an additional coping strategy. BMI levels classified both African age groups as obese, which is consistent with the findings of other South African 27,29,[33][34][35][36][37] and African studies. 28,38 Different studies agree that overweight and obesity are highly prevalent.…”

“…It was higher than the 12% reported by another study which also used the Joint Statement Criteria. 27 This difference could be explained by the fact that one study was urban and the other rural. Furthermore, it could implicate that there is an urban-rural difference, not only for BMI as suggested by Steyn et al, 28 but also for MetS prevalence.…”

“…It was also higher than the 30% reported in a rural study. 27 In this regard, the same reasons that were given for the men could be given for the women. The groups comprising women were healthier in terms of risk factors, than those comprising men.…”

“…A study in the urban epicentre of South Africa (Johannesburg and Soweto) found a 50% obesity prevalence, 37 similar to the 47% noted in a rural KwaZulu-Natal study. 27 When considering South Africa as a whole, the prevalence was only 27%. 28 This large difference could possibly be ascribed to the researchers' finding that there was a large urban-rural difference with regard to BMI.…”

Dietary management of the metabolic syndrome – one size fits all?

“…Motala et al (27) noted in a rural community of Zulu descent that the age-adjusted prevalence of metabolic syndrome was 22 . 1% on average, with a higher prevalence in women at 25% compared with men at 10 .…”