Effect of co-morbidities on fracture risk: Findings from the Global Longitudinal Study of Osteoporosis in Women (GLOW)

• DOI: 10.1016/j.bone.2012.02.639
• Publication Date: 2012-03-09T12:30:43Z
• Authors: Elaine M. Dennison; Juliet E. Compston; Julie Flahive; Ethel S. Siris; Stephen H. Gehlbach; Jonathan D. Adachi; Steven Boonen; Roland Chapurlat; Adolfo Díez-Pérez; Frederick A. Ande...; Frederick H. Hooven; Andrea Z. LaCroix; Robert Lindsay; J. Coen Netelenbos; Johannes Pfeilsch...; Maurizio Rossini; Christian Roux; Kenneth G. Saag; Philip Sambrook; Stuart Silverman; Nelson B. Watts; Susan L. Greenspan; Melissa Premaor; Cyrus Cooper
• Keywords: Aging; Clinical Sciences; GLOW Investigators; 610; Clinical sciences; Comorbidity; Medical and Health Sciences; fracture; osteoporosis; co-morbidities; Cohort Studies; Endocrinology & Metabolism; Engineering; Clinical Research; Risk Factors; 80 and over; Humans; Musculoskeletal Diseases; Longitudinal Studies; Bone; Osteoporosis, Postmenopausal; Aged; Proportional Hazards Models; Aged, 80 and over; Biomedical and Clinical Sciences; Prevention; Parkinson Disease; Biological Sciences; Middle Aged; 3. Good health; Osteoporosis; Postmenopausal; Female; Health Services Research; Fractures; Algorithms; Osteoporotic Fractures

Greater awareness of the relationship between co-morbidities and fracture risk may improve fracture-prediction algorithms such as FRAX.We used a large, multinational cohort study (GLOW) to investigate the effect of co-morbidities on fracture risk. Women completed a baseline questionnaire detailing past medical history, including co-morbidity history and fracture. They were re-contacted annually to determine incident clinical fractures. A co-morbidity index, defined as number of baseline co-morbidities, was derived. The effect of adding the co-morbidity index to FRAX risk factors on fracture prevention was examined using chi-squared tests, the May-Hosmer test, c index and comparison of predicted versus observed fracture rates.Of 52,960 women with follow-up data, enrolled between October 2006 and February 2008, 3224 (6.1%) sustained an incident fracture over 2 years. All recorded co-morbidities were significantly associated with fracture, except for high cholesterol, hypertension, celiac disease, and cancer. The strongest association was seen with Parkinson's disease (age-adjusted hazard ratio [HR]: 2.2; 95% CI: 1.6-3.1; P<0.001). Co-morbidities that contributed most to fracture prediction in a Cox regression model with FRAX risk factors as additional predictors were: Parkinson's disease, multiple sclerosis, chronic obstructive pulmonary disease, osteoarthritis, and heart disease.Co-morbidities, as captured in a co-morbidity index, contributed significantly to fracture risk in this study population. Parkinson's disease carried a particularly high risk of fracture; and increasing co-morbidity index was associated with increasing fracture risk. Addition of co-morbidity index to FRAX risk factors improved fracture prediction.