A significant decline in IGF-I may predispose young Africans to subsequent cardiometabolic vulnerability
Date
2010Author
Schutte, Aletta E.
Huisman, Hugo W.
Van Rooyen, Johannes M.
Malan, Leoné
Malan, Nicolaas T.
Fourie, Catharina M.T.
Louw, Roan
Van der Westhuizen, Francois H.
Schutte, Rudolph
Metadata
Show full item recordAbstract
Objectives: Low serum IGF-I is an independent risk factor for diabetes and cardiovascular disease. These noncommunicable diseases are extremely common in urban black South Africans, but their IGF-I concentration is unknown. We aimed to compare serum IGF-I concentrations of African and Caucasian people, investigate their age-related IGF-I decline, and determine whether IGF-I could account, at least in part, for the high prevalence of noncommunicable diseases in black Africans.
Research Design and Methods: This cross-sectional study involved 211 African and 316 Caucasian men and women (aged 20–70 yr). Fasting glucose, insulin, lipids, albumin, creatinine, liver enzymes, cotinine, high-sensitivity C-reactive protein, reactive oxygen species, IGF-I, blood pressure (BP), and pulse wave velocity were determined.
Results: IGF-I was lower in Africans (P < 0.001) and in both ethnicities declined significantly by age quartiles (P < 0.001). In African men and women, IGF-I declined significantly from age quartile 1 to 2 (r = −0.65, P < 0.001), not seen in young Caucasian men and women (r = −0.08, P = 0.45; r = −0.10, P = 0.34). This was confirmed after adjustment for BP, insulin resistance, high-sensitivity C-reactive protein, cotinine, γ-glutamyl transferase, and reactive oxygen species. Only young Africans showed significant negative correlations of IGF-I with BP, pulse wave velocity, and high-density lipoprotein cholesterol.
Conclusions: Africans presented lower IGF-I levels than Caucasians due to an accelerated decline in serum IGF-I concentration prior to 40 yr of age. Strong associations of low serum IGF-I with blood pressure and arterial stiffness in young Africans suggest that the loss of cardiometabolic protection by IGF-I could predispose them to earlier disease onset
URI
http://hdl.handle.net/10394/5956https://academic.oup.com/jcem/article-lookup/doi/10.1210/jc.2009-2329
https://doi.org/10.1210/jc.2009-2329