Relationships between serum IGF1 levels, blood pressure, and glucose tolerance: an observational, exploratory study in 404 subjects

Abstract

BackgroundIn the general population, low IGF1 has been associated with higher prevalence of cardiovascular disease and mortality.ObjectiveTo investigate the relationships between IGF1 levels, blood pressure (BP), and glucose tolerance (GT).SubjectsFour-hundred and four subjects (200 men aged 18–80 years). Exclusion criteria: personal history of pituitary or cardiovascular diseases; previous or current treatments with drugs interfering with BP, GT, or lipids, corticosteroids (>2 weeks), estrogens, or testosterone (>12 weeks); smoking of >15 cigarettes/day and alcohol abuse (>3 glasses of wine/day).ResultsTwo hundred and ninety-six had normal BP (73.3%), 86 had mild (21.3%), and 22 had severe (5.4%) hypertension; 322 had normal GT (NGT (79.7%)), 53 had impaired glucose tolerance (IGT (13.1%)), 29 had diabetes mellitus (7.2%). Normotensive subjects had significantly higher IGF1 levels (0.11±0.94 SDS) than those with mild (−0.62±1.16 SDS, P<0.0001) or severe (−1.01±1.07 SDS, P<0.0001) hypertension. IGF1 SDS (t=−3.41, P=0.001) independently predicted systolic and diastolic BP (t=−2.77, P=0.006) values. NGT subjects had significantly higher IGF1 levels (0.13±0.90 SDS) than those with IGT (−0.86±1.14 SDS, P<0.0001) or diabetes mellitus (−1.31±1.13 SDS, P<0.0001). IGF1 SDS independently predicted fasting glucose (t=−3.49, P=0.0005) and homeostatic model assessment (HOMA)-R (t=−2.15, P=0.033) but not insulin (t=−1.92, P=0.055) and HOMA-β (t=−0.19, P=0.85).ConclusionIGF1 levels in the low normal range are associated with hypertension and diabetes in subjects without pituitary and cardiovascular diseases.