Prevalence of metabolic syndrome among adolescents in Cape Town, South Africa: a cross-sectional analysis comparing five diagnostic criteria to explore suitability

Abstract

Background: Metabolic syndrome (MetS) among adolescents is a growing public health concern globally, yet data from sub-Saharan Africa remain scarce. Variability in diagnostic criteria further complicates surveillance efforts. This study aimed to estimate the prevalence of MetS among adolescents in Cape Town, South Africa, using five diagnostic criteria, to assess the agreement between definitions and explore criteria suitability. Methods: We conducted a cross-sectional study among 489 adolescents aged 13–18 years, sampled from coeducational public high schools in Cape Town's Metro South district. Anthropometric, blood pressure, and fasting biochemical measurements were collected. MetS prevalence was assessed using the Cook, Ford, de Ferranti, International Diabetes Federation (IDF), and Agudelo criteria. Agreement between definitions was evaluated using unweighted Kappa statistics. Results: The MetS prevalence with four criteria were similar, ranging from 4.7 % (IDF) to 5.7 % (Ford), while one criterion differed significantly with 17.8 % (de Ferranti). Central obesity and raised blood pressure were the most prevalent MetS components across criteria. Females exhibited higher MetS prevalence than males across the five criteria. Very good agreement was observed between Cook, Ford, and Agudelo definitions (κ > 0.85), while agreement involving IDF and de Ferranti definitions was fair to moderate (κ = 0.33–0.42). Conclusions: Our results underscore the need for locally validated, population-specific MetS criteria and diagnostic thresholds to support early identification of adolescents at risk of cardiometabolic disease (CMD). In the absence of such criteria, the Cook and Ford definitions appear particularly suitable for identifying MetS among South African adolescents, while the Agudelo definition is appropriate when waist circumference (WC) measures are unavailable. Finally, our findings reveal a concerning CMD risk profile among adolescents in Cape Town, South Africa, with a particularly high burden observed in females.