Differences in risk factor patterns between cervical and trochanteric hip fractures

• Published in: Osteoporosis international Vol. 10; no. 6; pp. 487 - 494
• Main Authors: MICHAËLSSON, K, WEIDERPASS, E, FARAHMAND, B. Y, BARON, J. A, PERSSON, P.-G, ZIDEN, L, ZETTERBERG, C, LJUNGHALL, S
• Format: Journal Article
• Language: English
• Published: London Springer 01.11.1999; Springer Nature B.V
• Subjects: Biological and medical sciences; Cervical; Estrogen; Height; Hip fracture; Injuries of the limb. Injuries of the spine; Medical sciences; MEDICIN; MEDICINE; Traumas. Diseases due to physical agents; Trochanteric; Sweden; Europe; Human; Femoral neck; Femur; Questionnaire; Diseases of the osteoarticular system; Clinical form; Lower limb; Fracture; Case control study; Trauma; Epidemiology; Etiology; Risk factor; Bone; Elderly; Public health; Pertrochanteric fracture
• ISSN: 0937-941X; 1433-2965; 1433-2965
• DOI: 10.1007/s001980050259

The two types of hip fracture - cervical and trochanteric femoral fractures - are generally considered together in etiologic studies. However, women with a trochanteric fracture may be more osteoporotic than those with cervical hip fractures, and have higher post-fracture mortality. To explore differences in risk factor patterns between the two types of hip fracture we used data from a large population-based case-control study in Swedish women, 50-81 years of age. Data were collected by questionnaire, to which more than 80% of subjects responded. Of the cases included, 811 had had a cervical fracture and 483 a trochanteric fracture during the study period; these cases were compared with 3312 randomly selected controls. Height and hormonal factors appeared to affect the risk of the two types of hip fracture differently. For every 5 cm of current height, women with a cervical fracture had an adjusted odds ratio (OR) of 1.23 (95% CI 1.15-1.32) compared with an OR of 1.06 (95% CI 0.97-1.15) for women with trochanteric fractures. Later menopausal age was protective for trochanteric fractures (OR 0.95, 95% CI 0.91-0.99 per 2 years) but no such association was found for cervical fractures. Compared with never smokers, current smokers had an OR of 1.48 (95% CI 1.12-1.95) for trochanteric fractures and 1.22 (95% CI 0.98-1.52) for cervical fractures. Current hormone replacement therapy was similarly protective for both fracture types, but former use substantially reduced risk only for trochanteric fractures: OR 0.55 (95% CI 0.33-0.92) compared with 1.00 (95% CI 0.71-1.39) for cervical fractures. These risk factor patterns suggest etiologic differences between the fracture types which have to be considered when planning preventive interventions.