Beyond waist circumference in an adult male population of Southern Italy: Is there any role for subscapular skinfold thickness in the relationship between insulin-like growth factor-I system and metabolic parameters?

Background: Apart from waist circumference, other adiposity measures, such as subscapular skin fold (SST), arouse growing interest due to their relationship to metabolic complications and cardiovascular risk. The IGF-I system is deregulated in obese subjects in proportion to their degree of visceral adiposity.
Aim: To examine the association among IGF-I, IGF-binding protein (BP)-1 and -3 levels and different measures of adiposity in a sample of adult male population in Southern Italy.
Materials and Methods: A complete database for this analysis was available for 229 (age range 50-82 yr) participating at 2002-2004 Olivetti Heart Study follow-up.
Results: After adjustment for age, IGF-I was inversely associated with body mass index (BMI) and waist circumference (p<0.05). IGFBP-1 was inversely associated with BMI, waist circumference, SST, homeostasis model assessment (HOMA) index, fat mass. HOMA index, age, and SST significantly predicted the IGFBP-1 plasma levels, with 24% of IGFBP-1 variability explained at a linear regression analysis.
Conclusions: IGFBP-1 inversely correlated to adiposity and HOMA index. Among adiposity indexes, SST was the best predictor of IGFBP-1 levels. The evaluation of some components of the IGF system, and simple measures of body adiposity, such as SST, may represent a further tool to better evidence phenotype profiles associated to the pathogenetic mechanism of cardiovascular risk factor clustering in male adults.