title: Evaluation of insulin like growth factor-1 (IGF-1) level and its impact on muscle and bone mineral density in frail elderly male.
abstract: Decrease in IGF-1 level is a major endocrine dysregulation that has been implicated in frailty, disability, and mortality in older adults. Our aim was to clarify the effect of IGF-1 on muscle and bone mineral density (BMD) in frail males. One hundred elderly males were included and divided into frail group (n=50) and robust group (n=50) based on the study of osteoporotic fractures (SOF) frailty index. Anthropometric measures, femoral BMD, and serum IGF-1 level were measured. Our results showed that the IGF-1 level was significantly lower in the frail males in comparison to the robust with mean value 37.1±24.2 versus 68.5±18.4ng/ml (P<0.05). Receiver operating curve (ROC) analysis of the IGF-1 level revealed that sensitivity was 88.5%, specificity was 100%, cutoff value was 46.5ng/ml and area under the curve (AUC) was 0.897 (P<0.05). Participants with low IGF-1 percentile had significantly higher odds ratio of being frail compared to those with high IGF-1 percentile (odds ratio=12.8, 95% CI: 4.2-38.8, P-value<0.05). Subjects with low IGF-1 percentile had 13.5 times the odds of having an abnormal BMD than those with middle IGF-1 percentile (95% CI: 3.4-53.3, P<0.05). In multivariate analysis BMD, mid arm circumference (MAC), mid calf circumference (MCC), and handgrip strength were significantly affected by IGF-1 percentiles with age and co-morbid diseases adjustment. Male subjects with a low IGF-1 level may be at risk of being frail and having abnormal BMD. 16.8% and 15% of variability in MCC and BMD may be attributed to IGF-1 level respectively.
authors.affiliation: Medical Biochemistry Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt. Electronic address: magdaibrahim_bio@yahoo.com.
authors.forename: Magda I
authors.initials: MI
authors.lastname: Mohamad
authors.affiliation: Geriatrics and Gerontology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Khater
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry; D015519:Bone Density / Q000502:physiology*; D004534:Egypt; D016330:Frail Elderly; D015577:Geriatric Assessment / Q000379:methods; D018737:Hand Strength; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000502:physiology*; D016017:Odds Ratio; D012372:ROC Curve; D012680:Sensitivity and Specificity
chemical_list: D007334:Insulin-Like Growth Factor I
keywords: Anthropometric measures; Bone mineral density; Elderly male; Frailty; IGF-1