Prevalence and Red Flags Regarding Specified Causes of Back Pain in Older Adults Presenting in General Practice

BACKGROUND: In a small proportion of patients experiencing unspecified back pain a specified underlying pathology is present.OBJECTIVE: To identify the prevalence of physician-specified causes of back pain and to assess associations between red flags and vertebral fractures, as diagnosed by the patients' GP, in older adults presenting with back pain in general practice.METHODS: The BACE study is a prospective cohort study. Patients (aged >55 years) with back pain were included when consulting their general practitioner (GP). A questionnaire, physical examination, and heel bone densitometry were performed and determined back pain and patient characteristics, including red flags. Patients received an X-ray and reports were send to the patients' GP. The final diagnoses established at 1 year were collected from the GPs patient registry.RESULTS: Of the 669 patients included, 6% were diagnosed during 1 year follow-up with a serious underlying pathology. Most of these patients (n=33, 5%) were diagnosed with a vertebral fracture. Multivariable regression analysis showed that age ≥ 75 years, trauma, osteoporosis, a back pain intensity score ≥7, and thoracic pain were associated with a higher chance of getting the diagnosis of a vertebral fracture. Of these variables, trauma showed the highest positive predictive value for vertebral fracture of 0.25 (95%CI 0.09-0.41) and a positive likelihood ratio of 6.2 (95% CI 2.8-13.5). A diagnostic prediction model including the five red flags did not increase these values.LIMITATIONS: Low prevalence of vertebral fractures could have led to findings by chance.CONCLUSIONS: In these older adults with back pain presenting in general practice 6% were diagnosed with serious pathology, mainly a vertebral fracture (5%). Four red flags were associated with the presence of vertebral fracture.