Self-reported physical functional health predicts future bone mineral density in EPIC-Norfolk cohort

Abstract

Using a large population sample from the UK, we found that self-reported physical functional health may be used to predict future bone mineral density especially in women. It may be a useful and inexpensive way to identify individuals before further decline in bone mineral density and the risk of fracture.

Purpose: Self-reported physical functional health may predict bone mineral density (BMD) and thus provide a method to identify people at risk of low BMD. In this study, the association between the 36-item short-form questionnaire (SF-36) physical component summary (PCS) score and future BMD in participants aged 40-79 years enrolled in the European Prospective Investigation of Cancer-Norfolk study was investigated.

Methods: Associations between a participant's SF-36 PCS score, measured 18 months after baseline health check, and broadband ultrasound attenuation (BUA-a measure of BMD), measured 2-5 years after baseline, were examined using sex-specific linear and logistic regression analyses adjusting for age, BMI, medical co-morbidities, lifestyle and socioeconomic factors.

Results: Data from 10,203 participants, mean (standard deviation (SD)) age 61.5 (8.9) years (57.4% women), were analysed from 1993 to 2000. For every five points lower PCS score in men and women, there was approximately a 0.5 dB/MHz lower mean BUA. In women, a PCS score of less than one standard deviation (1SD) below the sex-specific mean was associated with having a low BUA (< 1SD below sex-specific mean) and very low BUA (< 2.5SD below the sex specific mean); odds ratio (OR) (95% confidence interval) 1.53 (1.24, 1.88) and 8.28 (2.67, 25.69), respectively. The relationship was lesser so in men; corresponding OR (95% CI) were 1.34 (0.91, 1.98) and 2.57 (0.72, 9.20), respectively.

Conclusions: Self-reported physical functioning predicts BMD in an apparently healthy population, particularly in women. This could potentially provide an inexpensive, simple screening tool to identify individuals at risk of osteoporosis.

Keywords: Bone mineral density; Older adults; Physical functioning; SF-36.