**5.6 Cardiovascular disease**

In relation to high BMI, cardiovascular disease (CVD) was the leading cause for death and disability-adjusted life-years (DALY). It accounted for 2.7 million deaths and 66.3 million DALY. Among the obese, 41% of deaths and 34% of DALY were due to CVD [5]. Current adolescent overweight prevalence is estimated to increase future adult obesity by 5–15% by 2035, and this will result in an additional 100,000 CVD cases [84]. Cardiovascular disease associated with obesity is usually secondary to hypertension (already discussed above) and atherosclerosis. Atherogenesis is mainly due to sub-intimal deposition of LDLcholesterol particles. The combined atherogenicity of childhood obesity is an ideal scenario for this to occur. High circulating levels of small LDL-cholesterol particles and decreased clearance of the same by LDL receptors increases risk of their entrapment in the sub endothelial matrix. Further, low levels of HDLcholesterol limit reversal of cholesterol transport. An objective measure of the damaging potential of atherogenicity of combined dyslipidaemia in childhood is the carotid intimal-media thickness (cIMT). The Young Finns study followed up children from childhood for 21 years. Children with combined dyslipidaemia had significant cIMT compared to normo-lipidaemic controls even after adjusting for other factors [85]. The Childhood Cardiovascular Cohort (i3C) was a 23.4 years follow-up of 2893 children aged 12–18 years across three continents. i3C data showed a strong correlation between childhood obesity, hypertension and dyslipidaemia with high cIMT in adulthood. Obesity increased the risk for high cIMT 3.7 (2.0–7.0)-fold and hypertension by 1.9 (1.3–2.9)-fold [86]. Another study showed that 90% of children with high cIMT also had left ventricular hypertrophy [87]. Obesity has been associated with a 50% increase in heart-failure incidence among young adults (18–34 years) from 1987 to 2006 in the US [88]. The frequency of stroke and renal failure are also higher in young adults with history of childhood obesity [89, 90]. In a recent study published in JAMA, positive associations were observed between consumption of artificially sweetened soft drinks and death due to circulatory diseases (>2 drinks/day vs. <1 glass per month; HR 1.52; 95%CI 1.30–1.78, p = 0.001) [91].

Sub-clinical vascular inflammation may also be a contributory factor to development of CVD. In Indian adolescents, raised C-reactive protein (CRP) levels are seen in 13% of all subjects, 22% of overweight and 25% of obese ones. CRP levels have a strong association with percentage body fat, WHR, waist circumference and triceps skin-fold thickness [92].
