IGFBP-1 predicts all-cause mortality in elderly women independently of IGF-I

Previous studies on the insulin-like growth factor (IGF) system and mortality have shown ambiguous results. We investigated the association between IGF-I and insulin- like growth factor binding protein-1 (IGFBP-1) with all-cause mortality in an elderly female Swedish population.

A prospective cohort study of elderly women (n=338) aged between 68 and 79 years (mean age 72 years) with a mean follow-up time of 9.9 years. Baseline data in the PRIMOS (Primary Health Care and Osteoporosis) study were collected between 1999 and 2001. Data of risk factors for cardiovascular disease were collected. Death rates were registered from the Swedish Cause of Death register for the period 1999-2009. Cox regression models were used to calculate hazard ratios. IGF-I and IGFBP-1 levels were separately divided into 3 groups (high, medium and low), with cut offs at the 30th and the 70th percentiles.

In a fully adjusted Cox proportional hazard model, increased risk of mortality was shown for women with high serum levels of IGFBP-1, HR 3.03 (95% CI 1.64-5.63) and also with low serum levels of IGFBP-1, HR 1.98 (95% CI 1.03-3.81), compared to women with moderate levels. No significant association between IGF-I and mortality was observed.

High and low serum insulin-like IGFBP-1 levels were associated with an increased risk of all-cause mortality in elderly women, compared to moderate levels.