Visceral adiposity index, fitness and clustered cardiovascular disease risk in adolescents.

BACKGROUND:  Clustering of cardiovascular disease (CVD) risk factors have been observed in children and adolescents, but its association with visceral adiposity index (VAI) and cardiorespiratory fitness (CRF) in adolescents has rarely been studied. AIM:  This study determines the independent associations of VAI and CRF with the clustering of cardiovascular disease risk (CVDr) among Nigerian adolescents. SETTING:  Adolescents from specific secondary schools in Kogi East, North Central Nigeria participated in the study. METHODS:  A cross-sectional sample of 403 adolescents (202 boys and 201 girls) aged 11 years - 19 years were evaluated for VAI, CRF and CVDr. Using identified risk factors, a clustered CVDr score was generated. The association between VAI, CRF and clustered CVDr was evaluated using regression models that controlled for age, gender and maturity status. RESULTS:  Fitness was negatively associated with CVDr (ß = -0.268, p  0.001), while VAI was positively correlated with CVDr (ß = 0.379, p  0.001). After CRF or VAI adjustment, the independent association with the dependent variable remained significant. The odds of an adolescent with elevated VAI being at risk of CVD was 4.7 times higher than his peers. Unfit adolescents were 2.1 times more likely to develop CVDr. CONCLUSION:  Both VAI and CRF were independently associated with the clustering of CVDr in Nigerian adolescents. The findings suggest that health promotion efforts focusing on healthy diet and aerobic-type physical activity programmes should be encouraged among the youth to reduce the risk of CVD.Contribution: This study shows that improving visceral adipose tissue and fitness may lower CVD risk factors in adolescents, which is significant for public health.

Prevalence of childhood and adolescent overweight and obesity in Benue State, Nigeria.

OBJECTIVE: To evaluate demographic variation in the prevalence of overweight (OW) and obesity (OB) among 3240 children and adolescents (girls: n = 1714; boys: n = 1526) aged 9-16 years attending primary and secondary schools in Benue State of Nigeria. METHODS: Participants' anthropometric characteristics (body weight, stature, body mass index: BMI and lean body mass: LBM) were determined using standard protocols. OW and OB were estimated using International Obesity task Force diagnostic criteria. Data were analysed with one-way anova and binary logistic regression method. RESULTS: Overall, 88.5%, 9.7% and 1.8% of the adolescents had normal BMI and were OW and obese, respectively. Prevalence of OW was higher among girls (20.3%) than boys (16.2%), whereas a relatively higher incidence of OB was noted among the boys (3.5%). Girls in urban areas had a significantly higher BMI (t524 = 3.61, P = 0.002) than their rural peers, but the rural girls were more significantly OW than their urban counterparts (BMI: t1186 = 2.506). Logistic regression models assessing the influence of age, gender and location on OW/OB in children (α(2) (3, N = 1014) = 6.185, P = 0.103) and adolescents (α(2) (3, N = 2226) = 1.435, P = 0.697) did not turn up significant results. In the gender-specific analysis, the younger boys' model was also not significant (α(2) (2, N = 488) = 1.295, P = 0.523) in contrast to the girls' (α(2) (2, N = 526) = 15.637, P = 0.0005), thus discriminating between OW and healthy weight among the children. Overall, the model explained 2.9-4.4% of the variance in weight status and correctly classified 76.8% of the cases. Age wise, the model yielded a significant odds ratio of 1.49, suggesting that the likelihood of being OW increases by a factor of 1.5 with a unit increase in age. Also, the likelihood of an urban girl becoming OW or obese was 0.57 times that of a rural girl. CONCLUSIONS: In general, girls in urban areas had higher prevalence of OW and OB than girls in rural settings. Among the boys, similar but less marked trends were found, except that the rural boys tended to be more OW on average than their peers in urban areas. In view of its public health significance, it is important to periodically evaluate the prevalence of weight disorders in children and adolescents so that appropriate preventative strategies can be instituted.

Association of Fitness and Fatness with Clustered Cardiovascular Disease Risk Factors in Nigerian Adolescents.

Purpose: This study examinedthe independent and joint association of fitness and fatness with clustered cardiovascular disease risk (CVDrs) in 11-18 year-old Nigerian adolescents. Methods: A hundred and ninety seven adolescents (100 girls and 97 boys) were evaluated forfitness, fatness and CVDrs. Fitness was evaluated with the progressive aerobic cardiovascular endurance run test while fatness was assessed using body mass index. A clustered CVDrs was computed from the standardized residuals of total cholesterol, high density lipoprotein cholesterol, Low density lipoprotein cholesterol, triglycerides, plasma glucose, systolic blood pressure, and diastolic blood pressure. Regression models controlling for waist circumference assessed the association of fitness and fatness with CVDrs. Results: Prevalence of clustered CVD risk was 7.1% (girls = 3.0%; boys = 4.1%). Based on risk factor abnormalities, 52.8% of participants had one or more CVD risk factor abnormalities with more boys (27.4%) affected. Low fitness was associated with clustered CVDrs in both girls (R2 = 9.8%, ß = -0.287, p = 0.05) and boys (R2 = 17%, ß = -0.406, p < 0.0005). Fatness was not associated with the CVDrs in both sexes. After controlling for all the variables in the model, only fitness (R2 = 10.4%) and abdominal fat (R2 = 19.5%) were associated with CVDrs respectively. Unfit girls were 3.2 (95% CI = 1.31-7.91, p = 0.011) times likely to develop CVD risk abnormality compared to their fit counterparts. The likelihood of unfit boys developing CVD risk abnormality was 3.9 (95% CI = 1.15-10.08, p = 0.005) times compared to their fit peers. Conclusions: Fitness but not fatness was a better predictor of CVDrs in Nigerian boys and girls. The result of this study suggests that any public health strategies aimed at preventing or reversing the increasing trends of CVD risk in adolescents should emphasize promotion of aerobic fitness.

The effect of a high-intensity interval training program on high-density lipoprotein cholesterol in young men.

This study examined the impact of an 8-week program of high-intensity interval training on high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and the atherogenic index (TC/HDL-C) in 36 untrained men ages 21-36 years. Participants were randomly assigned to an interval training group (n = 20) or a control group (n = 16). Participants in the experimental group performed 3.2 km of interval running (1:1 work:rest ratio) 3 times a week for 8 weeks at an intensity of 90% of maximal heart rate ( approximately 423 kcal per session). Results indicated significant pre- to posttraining changes in HDL-C (1.1 vs. 1.3 mmolxL, p < 0.0001) and TC/HDL-C (3.8 vs. 3.1, p < 0.0001) but no significant changes in TC (3.9 vs. 3.8 mmolxL, p > 0.05) with interval training. It was concluded that an 8-week program of high-intensity interval training is effective in eliciting favorable changes in HDL-C and TC/HDL-C but not TC in young adult men with normal TC levels. Our findings support the recommendations of high-intensity interval training as an alternative mode of exercise to improve blood lipid profiles for individuals with acceptable physical fitness levels.

Cardiorespiratory fitness, fatness, and blood pressure associations in Nigerian youth.

PURPOSE: This study aimed to examine the independent associations of cardiorespiratory fitness (CRF) and body fatness with resting blood pressure (BP) in children (9-11 yr) and adolescents (12-15 yr) in Benue State of Nigeria. METHODS: A total of 3243 children (n = 1017) and adolescents (n = 2226) were evaluated for aerobic fitness, body fatness, resting preexercise BP and recovery BP at minutes 1, 5, and 10 after a progressive aerobic cardiovascular endurance run test. Regression models, controlling for age and recovery BP at 1, 5, and 10 min after the progressive aerobic cardiovascular endurance run, determined the associations of independent variables with the dependent variables. RESULTS: Fatness and fitness were independent predictors of resting BP among participants, and the relationship of fatness with BP was more robust in adolescents than in children. In all cases, the relationships were stronger in boys than in girls. Combined fitness and fatness in predicting BP was modest (R(2) = 1%-3%) after controlling for age and postexercise BP. Postexercise BP was a major determinant of resting BP in both groups (R(2) = 23%-93%). In adolescents, fatter boys had 1.9 times likelihood of systolic HTN compared with leaner peers. Systolic and diastolic BP scores varied by fit-fat groups, the fit-low-fat group demonstrated the most favorable BP profiles, whereas the unfit-high-fat group showed the most adverse profiles. CONCLUSIONS: Irrespective of fatness, participants with higher CRF had more favorable BP profiles compared with their fat-unfit peers.