Objective: To evaluate the diagnostic utility of recommended body mass index (BMI)-based classification systems in detecting excess body fat (BF) in an Afro-Caribbean adolescent population. Subjects: All adolescents aged 12-18 years were invited to participate in the study. A total of 3749 persons participated fully in the study. Result: Males (12.2%) (95% confidence interval (CI): 10.7, 13.9) and females (43.6%) (95% CI: 41.5, 45.7) had excess adiposity. Specificities were high for all cutoff values (range 90.1-99.7%). Sensitivities ranged from 25.7 to 86.4% and from 15.6 to 54.4% for Centre for Disease Control (CDC) and International Obesity Task Force (IOTF) cutoff values, respectively. The mean areas under the receiver-operating characteristic curves ranged from 62.7 to 88.2% in males and 57.7 to 75.1% in females, while positive likelihood ratios ranged from 8.7 to 90.9 for the recommended BMI cutoff values. Conclusions: Overall, the CDC cutoffs had a higher sensitivity than the IOTF cutoffs in screening for excess fat. Specificities were high for cutoff values in both systems and would produce fewer false negatives.

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Objective: The aim of this study was to determine the effect of growth pattern on blood pressure changes in an adolescent population of African ancestry based on longitudinal data and to compare this with estimates derived from cross-sectional data.Methods: Participants had measurements of weight, height, blood pressure and percentage body fat taken annually using standardized procedures. Annual blood pressure and anthropometry velocities as well as one-and three-year interval gender specific tracking coefficients were computed. We investigated whether changes in blood pressure could be explained by measures of growth using a multilevel mixed regression approach. Results:The results showed that systolic blood pressure (SBP) increased by 1.27 and 3.09 mmHg per year among females and males, respectively. Similarly, diastolic blood pressure (DBP) increased by 1.16 and 1.92 mmHg per year among females and males, respectively. Multilevel analyses suggested that weight, body mass index, percentage body fat and height were the strongest anthropometric determinants of blood pressure change in this population.

Childhood and adolescent obesity is increasingly becoming a major public health issue in the Caribbean. In this study, we analyze patterns of growth in a population of Afro-Caribbean adolescents 12-18 years old and to compare these with those established for US adolescents. A cross-section of adolescent schoolchildren had weight and height measured using standardized procedures. In addition, percentage body fat (% BF) was measured using a foot-to-foot bioelectric impedance body fat analyzer (Tanita model 531). Selected age- and gender- specific percentiles of BMI, %BF, weight and height were derived and smoothed by cubic splines. These were compared with similar percentiles from US adolescent growth data. A total of 3,707 adolescents (1,585 males; 2,122 females) participated in the study. The age-specific correlation between BMI and %BF ranged from 0.75 to 0.87 in males and 0.79 to 0.87 in females. Females had significantly higher %BF than males in each age category. Overall, Tobagonian females were heavier and had higher BMI than their US counterparts especially levels above the median percentiles. Tobagonian males had similar height, weight, and BMI to their US counterparts over the range of percentiles. Overall, the pattern of growth in this group of adolescents suggests that they are growing at rates that are comparable to those seen in a more well-nourished population.