Common Questions
Is physical inactivity a clinical risk factor for osteoporosis-related fractures?
Physical inactivity is not usually considered a major risk factor for osteoporosis. However, two recent large prospective observational studies have shown that older white women who are sedentary are at significantly higher risk (20 percent to 40 percent increased risk) for future hip fracture as compared to women who are currently moderately physically active (2 to 4 hours of exercise per week) (1, 2). These data are supported by many case-control studies in a variety of populations (3-9).
Data from the Study of Osteoporotic Fractures Research Group (9) showed a significant association between activity level and hip fractures, even after adjusting for other known risk factors for osteoporotic fracture. Some of the findings of this study are summarized below.
| Variable | Patients (%) | Fractures (n) | Multivariate Relative Risk (95% CI) |
|---|---|---|---|
| Quintile of total physical activity: | |||
| Lowest | 20 | 132 | 1.00 |
| Second | 20 | 87 | 0.77 (0.58 to 1.02) |
| Third | 20 | 82 | 0.78 (0.59 to 1.04) |
| Fourth | 20 | 65 | 0.64 (0.47 to 0.88) |
| Highest | 20 | 58 | 0.64 (0.45 to 0.89) |
| P = 0.003 | |||
| Sport or recreational activity: | |||
| None | 20 | 129 | 1.00 |
| Low intensity | 50 | 217 | 0.76 (0.61 to 0.95) |
| Moderate to vigorous intensity | 30 | 80 | 0.58 (0.49 to 0.79) |
| P = 0.0004 | |||
| Hours sitting per day: | |||
| < 6 | 33 | 119 | 1.0 |
| 6 to 8 | 40 | 151 | 0.98 (0.77 to 1.25) |
| > 8 | 27 | 155 | 1.37 (1.08 to 1.76) |
| P= 0.01 |
CI = Confidence Interval. Adjusted for age, weight, smoking, estrogen replacement therapy, dietary calcium, falls, alcohol intake, self-rated health, and functional difficulty.
- Hoidrup S, Sorensen TI, Stroger U, Lauritzen JB, Schroll M, Gronbaek M. Leisure-time physical activity levels and changes in relation to risk of hip fracture in men and women.. Am J Epidemiol 2001; 154(1): 60-8.
- Gregg E, Cauley JA, Seeley DG, et al. Physical activity and osteoporotic fracture risk in older women. Ann Intern Med 1998; 129: 81-8.
- Gregg EW, Pereira MA, Caspersen CJ. Physical activity, falls, and fractures among older adults: A review of the epidemiologic evidence. J Am Geriatr Soc 2000; 48(8): 883-93.
- Boonyaratavej N, Suriyawongpaisal P, Takkinsatien A, Wanvarie S, Rajatanavin R, Apiyasawat P. Physical activity and risk factors for hip fractures in Thai women. Osteoporos Int 2001; 12(3): 244-8.
- Lau EM, Suriwongpaisal P, Lee JK, Das De S, Festin MR, Saw SM, Khir A, Torralba T, Sham A, Sambrook P. Risk factors for hip fracture in Asian men and women: The Asian osteoporosis study.. J Bone Miner Res 2001; 16(3): 572-80.
- Johnell O, Gullberg B, Kanis JA, et al. Risk factors for hip fracture in European women: The MEDOS Study.. J Bone Miner Res 1995; 10: 1802-15.
- Farahmand BY, Persson PG, Michaelsson K, Baron JA, Alberts A, Moradi T, Ljunghall S. Physical activity and hip fracture: A population-based case-control study. Swedish Hip Fracture Study Group. Int J Epidemiol 2000; 29(2): 308-14.
- Paganini-Hill A, Chao A, Ross RK, Henderson BE. Exercise and other factors in the prevention of hip fracture: The Leisure World study. Epidemiology 1991; 2(1): 16-25.
- Cummings SR, Nevitt MC, Browner WS, Stone K, Fox KM, Ensrud KE, et al. Risk factors for hip fracture in white women. Study of Osteoporotic Fractures Research Group. N Engl J Med 1995; 332: 767-73.
- Farmer ME, Harris T, Madans JH, et al. Anthropometric indicators and hip fracture: The NHANES I Epidemiologic Follow-up Study.. J Am Geriatr Soc 1989; 37: 9-16.