ALCOHOL WITHDRAWAL-INDUCED CHANGE IN LIPOPROTEIN(A) - ASSOCIATION WITH THE GROWTH HORMONE INSULIN-LIKE GROWTH-FACTOR-I (IGF-I)/IGF-BINDING PROTEIN-1 (IGFBP-1) AXIS/

Lipoprotein(a) [Lp(a)] is an important risk factor for cardiovascular disease. Alcohol is one of the few nongenetic factors that lower Lp(a) levels, but the metabolic mechanisms of this action are unknown. Alco hol inhibits the growth hormone (GH)/insulin-like growth factor-I (IGF -I) axis. Alcohol might also affect IGF-binding protein-1 (IGFBP-1), w hich is an acute inhibitor of IGF-I. We studied how alcohol withdrawal affects Lp(a) levels and the GH/IGF-I/IGFBP-1 axis. Male alcohol abus ers (n=27; 20 to 64 years old) were monitored immediately after alcoho l withdrawal for 4 days. Twenty-six healthy men, mainly moderate drink ers, served as control subjects. Fasting blood samples were drawn to d etermine Lp(a), IGF-I, and IGFBP-1 (by ELISA, RIA, and immunoenzymomet ric assay, respectively). Nocturnal (12 hours) urine collection was pe rformed in 9 alcoholics and 11 control subjects for GH analyses (RIA). The groups were similar in age and body mass index. Lp(a), GH, and IG F-I tended to be lower and IGFBP-1 higher in the alcoholics immediatel y after alcohol withdrawal than in the control subjects. During the 4- day observation in alcoholics, Lp(a) levels increased by 64% and IGF-I levels by 41%, whereas IGFBP-1 levels decreased by 59% (P<.001 after ANOVA for all comparisons). Urinary GH levels tended to decline. The i ncrease in Lp(a) correlated inversely with the changes in IGFBP-1 (r=- .63, P<.001, n=27) and GH (r=-.70, P<.05, n=9), but not with IGF-I. In multiple regression analysis, the main predictors for the increase in Lp(a) were IGFBP-1 and urinary GH. In conclusion, alcohol withdrawal induces interrelated and potentially atherogenic changes in Lp(a) and IGFBP-1 levels.