Back pain is the leading cause of years lived with disability in industrialised countries, with the annual prevalence of low back pain (LBP) being estimated at between 15% and 45%. Furthermore, it is estimated that up to 80% of the population will experience back pain in their lifetime, making it a major public health problem. Despite imposing great costs on patients and their families, employers, health care providers and society, incremental healthcare costs attributed to back pain, and characterisation by patient and clinical factors have rarely been documented.
Yet, understanding the economic burden and other costs imposed by back pain is important to ensure the value of interventions to reduce this burden is not inappropriately dismissed. The costs associated with back pain were last estimated over 20 years ago and reported that the direct health care cost of back pain in 1998 was £1.6 billion. The authors of that study suggested that the economic burden of back pain would rise in the future due to a combination of changing methods of healthcare provision, and changes in health-seeking behaviour.
The authors of a recent study therefore aimed to provide a current estimate of annual health care costs attributed to back pain.
Design and Methods of the Study
The researchers analysed data from the IQVIA Medical Research Data (IMRD) primary care database which contains pseudo-anonymised medical records of more than 15 million patients derived from 760 general practices in the UK. This database contains information about symptoms, investigations and diagnoses which is recorded using a clinical hierarchy coding system. The IMRD has been demonstrated to be representative of the UK population in terms of demographic structure and common morbidity prevalence.
The researchers used a retrospective, matched case-control design to isolate resource use and cost associated with back pain in 2015 (the year with the most complete recent data available). They then compared the healthcare costs of consultations and prescription drugs for patients with back pain (cases) with those without back pain (controls). Patients aged 18 or over who had their first diagnosis for back pain in the 10-year observation period (January 2006-December 2015) were included in the analysis. Cases were required to have been prescribed at least one prescription drug for pain in the same year as their diagnosis.
The study focused on primary care healthcare utilisation, including consultations and prescribed drugs. Physiotherapy and secondary care healthcare resource use (including A&E visits) were not included. The annual incremental costs associated with the treatment of back pain in 2015 were calculated as the difference between the total cost for the cases and the controls.
Results of the Study
Initially, a total of 914,461 cases were identified along with 1,862,230 controls. Of these, 133,341 cases met the sample selection and were 1:1 matched with controls. In both groups, the average age of patients was around 57 years old and 62% were female.
Both the main analysis and the sensitivity analysis showed that the annual all-cause healthcare resource use in the back pain group was nearly double that of the control group. The annual incremental costs of consultations associated with back pain were £25.3 million (£27.9 million in 2020 prices), with the cost per patient amounting to £187.7 (£209.5 in 2020) in the main analysis and £223.5 in the sensitivity analysis.
Counts of prescriptions and/or rates of prescriptions were three times higher in back pain patients compared to controls. The annual incremental costs of prescriptions per patient was £54.4 (£60.1 in 2020) in the main analysis while this dropped to £47.0 per patient in the sensitivity analysis.
The total incremental costs of back pain amounted to £32.5 million (£35.9 million in 2020), with a per-patient cost of £244 (£265 in 2020) per year. The sensitivity analysis estimated costs at £270 per patient per year. Around 80% of the total cost difference between the case and control groups was attributed to consultations. It was estimated that the incremental cost associated with back pain cost the healthcare system £3.2 billion in 2015 (£3.5 billion in 2020).
The data assessed in this study indicate the significant economic impact of back pain to the National Health Service. However, the authors note that this only represents the costs attributable to general practice, with the wider costs to the health care service expected to be even higher due to costs incurred in secondary care settings.
Furthermore, conservative cost estimates were used as some antidepressant medication types were excluded based on the prevailing guideline for lower back pain; however, the authors note that these medications may still be relevant for some back pain patients. It is also possible that patients with back pain are prescribed other medications more often than controls due to back pain-related non-painful conditions, which may have led to further underestimation of costs.
The authors accept some limitations in the present study, including the exclusion of the costs of physiotherapy in primary care. Nonetheless, this study provides an important insight into the annual healthcare resource utilisation and costs of back pain in the UK primary care, highlighting cost variations across socio-demographic and clinical factors.