What is the prevalence and impact of osteoporotic vertebral fractures in older women with back pain? Vfrac: Population-based cohort study

Problem

Osteoporotic vertebral fractures (OVF) are one of the most important fractures in older people. Such fractures are associated with a reduced quality of life and are an indication that affected individuals have high risks for future fracture. Despite this, less than one-third are diagnosed and managed appropriately, largely because of an absence of guidance about what clinical factors should trigger referral for diagnostic spinal radiographs. To help healthcare professionals particularly in primary care refer patients for investigation, the ‘Vfrac’ study is developing a simple clinical checklist to identify which older women with back pain should have a spinal radiograph to diagnose or exclude OVF. To date we have recruited and analysed data from the first 380 women to identify the prevalence of OVF in community-dwelling older women with back pain, and to identify the impact on health-related quality of life (HRQOL).

Approach

Women aged 65 and older registered with a GP in Bristol and Stoke-on-Trent were invited to take part by mail-out from primary care. Those who self-reported back pain in the previous 4 months were eligible. Participants completed a questionnaire, received a simple physical examination by a trained research nurse and had a spinal radiograph using standard NHS techniques. All radiographs were assessed for the presence or absence of OVF by a trained clinician. Self-reported HRQOL was assessed by a sub-section of the EQ-5D (a scale of 0=bad to 100=good). A sample size of 1633 was required to estimate the sensitivity and specificity of the checklist with adequate precision (5% margin of error around values >80%), based on a literature review that identified an assumed prevalence of OVF of 12%. Univariable associations between OVF and categorical variables were assessed using Ch-squared tests. Linear regression was used to assess association between OVF and HRQOL, and multivariable analyses were used to adjust for potential confounders.

Findings

Of 380 participants, the prevalence of OVF was 15.5%. Those with OVF were older (77.8 years ± 7.1 vs 72.9 ± 5.5) and reported higher use of walking aids (48.3% vs 22.2%) compared with those without OVF. No differences were seen in walking distance, falls or smoking between those with and without OVF. No differences were identified in health-related quality of life between those with and without OVF (66 ± 24 vs 70 ±22) even after adjustment for age and mobility.

Consequences

15% of older women in the community with back pain have OVF. However, this is not associated with a reduction in health-related quality of life when compared to women with back pain due to other reasons. Further analysis is required once the full sample size has been collected.