Central obesity: predictive value of skinfold measurements for subsequent ischaemic heart disease at 14 years follow-up in the Caerphilly Study.

Abstract

To assess the predictive value of central obesity for risk of ischaemic heart disease (IHD) in a long-term follow-up, measured by skinfold thickness in comparison to general measures of overweight and obesity such as Quetelet's index. A total of 2512 men aged 45-59 y from the general population first examined in 1979-1982. Men were re-examined at approximately 5 y intervals. All fatal and non-fatal cases of IHD during a 14 y follow-up were recorded. Skinfold thickness was measured at four sites. Height (m) and weight (kg) were also measured and Quetelet's index (weight/height(2)) was used as the reference body mass index (BMI). Data were available for 2512 men among whom 411 new cases of IHD (fatal and non-fatal) occurred during 14 y of follow-up. Increasing values of BMI showed a statistically significant trend with increasing risk of new IHD that contributed independently to risk of IHD when adjusted for age, smoking habit and social class. Skinfold thickness measures were entered singly and in combination into this model with and without the additional inclusion of BMI. All individual skinfolds were significantly associated with risk of new IHD when BMI was excluded from the regression model, as was the sum of four skinfolds and the sum of subscapular and abdominal skinfolds. Only the subscapular skinfold measure contributed independently to risk of subsequent IHD when BMI was included in the model although biceps, biceps plus triceps and total sum of skinfolds were close to achieving statistical significance. The relative odds of IHD in the upper quintile of subscapular skinfold compared to the lowest was 1.9 (95% CI 1.3-2.8) when adjusted for age, smoking habit and social class. In general skinfold measurements contribute only marginally to improved prediction of risk of IHD as measured by BMI, but central obesity, as measured by the subscapular skinfold, is predictive of IHD independently of BMI.