- Dennison, Elaine M
- Compston, Juliet E
- Flahive, Julie
- Siris, Ethel S
- Gehlbach, Stephen H
- Adachi, Jonathan D
- Boonen, Steven
- Chapurlat, Roland
- Díez-Pérez, Adolfo
- Anderson, Frederick A
- Hooven, Frederick H
- LaCroix, Andrea Z
- Lindsay, Robert
- Netelenbos, J Coen
- Pfeilschifter, Johannes
- Rossini, Maurizio
- Roux, Christian
- Saag, Kenneth G
- Sambrook, Philip
- Silverman, Stuart
- Watts, Nelson B
- Greenspan, Susan L
- Premaor, Melissa
- Cooper, Cyrus
- GLOW Investigators
- et al.
INTRODUCTION:Greater awareness of the relationship between co-morbidities and fracture risk may improve fracture-prediction algorithms such as FRAX. MATERIALS AND METHODS: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. RESULTS: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. CONCLUSION: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.