Body Composition, IGF1 Status, and Physical Functionality in Nonagenarians: Implications for Osteosarcopenia

Eleonora Poggiogalle, Pennington Biomedical Research Center, Baton Rouge, LA; Department of Experimental Medicine- Medical Pathophysiology, Food Science and Endocrinology Section, Sapienza University, Rome, Italy. Electronic address: eleonora.poggiogalle@uniroma1.it.
Katie E. Cherry, Department of Psychology, Louisiana State University, Baton Rouge, LA.
L Joseph Su, Department of Epidemiology, University of Arkansas for Medical Sciences, Little Rock, AR.
Sangkyu Kim, Tulane Center for Aging and Department of Medicine, Tulane University Health Sciences Center, New Orleans, LA.
Leann Myers, Department of Global Biostatistics and Data Science, School of Public Health and Tropical Medicine, Tulane University Health Sciences Center, New Orleans, LA.
David A. Welsh, Department of Medicine, Louisiana State University Health Sciences Center, New Orleans, LA.
S Michal Jazwinski, Tulane Center for Aging and Department of Medicine, Tulane University Health Sciences Center, New Orleans, LA.
Eric Ravussin

Abstract

OBJECTIVES: Body composition alterations occur during aging. The purpose of the present analysis was to explore the functional consequences of the overlap of sarcopenia and osteoporosis, and the potential role of insulin-like growth factor 1 (IGF1) in their development in the oldest old. SETTING AND PARTICIPANTS: Eighty-seven nonagenarians from the Louisiana Healthy Aging Study were included. MEASURES: The definition of sarcopenia was based on appendicular lean mass (ALM). Osteoporosis was diagnosed based on bone mineral density (BMD) T score. Four phenotypes were compared: (1) healthy body composition, that is, nonosteoporotic nonsarcopenic (CO, control group), (2) osteoporotic (O, low BMD T score), (3) sarcopenic (S, low ALM), and (4) osteosarcopenic (OS, low BMD T score and low ALM). Sex- and age-specific IGF1-Standard Deviation Scores (SDS) were calculated. The Continuous Scale-Physical Functional Performance (CS-PFP) test was performed. RESULTS: In OS men, IGF1-SDS values (-0.61 ±0.37 vs -0.04 ± 0.52, P = .02) were lower than those in CO males (control group), whereas IGF1-SDS were similar in the 4 body composition phenotypes in women. In men only, ALM was positively associated with IGF1-SDS values (P = .01) independent of age and C-reactive protein concentration. Regarding bone health, we found no association between IGF1-SDS values and BMD. IGF1-SDS was not associated with functional performance (CS-PFP) in men and women. CONCLUSIONS/IMPLICATIONS: IGF1 sensitivity in skeletal muscle and bone may differ by sex in the oldest old. IGF1 status did not appear to affect physical functionality. Determinants and clinical and functional characteristics of osteosarcopenia need to be further investigated in order to define conclusive diagnostic criteria.