An Observational Retrospective Matched Cohort Study of Healthcare Resource Utilisation and Costs in UK Patients with Moderate to Severe Osteoarthritis Pain

Abstract

Introduction: Using data from patients residing in Salford, UK, we aimed to compare healthcare resource utilisation (HCRU) and direct healthcare costs between patients with moderate to severe (M-S) or severe osteoarthritis (OA) pain and those without OA.

Methods: Patients with a M-S OA pain event within a period of chronic pain were indexed from the Salford Integrated Record (SIR) between 2010 and 2017. Patients with a severe pain event formed an OA subcohort. Patients in each OA pain cohort were independently matched to patients without OA, forming two control cohorts. HCRU, prescribed analgesic drugs, and total direct costs per UK standardised tariffs were calculated for the year post-index. Multivariable models were used to identify drivers of healthcare cost.

Results: The M-S OA pain and control cohorts each comprised 3123 patients; the severe OA pain and control cohorts each comprised 1922 patients. Patients in both OA pain cohorts had a significantly higher mean number of general practitioner encounters, inpatient, outpatient, and accident and emergency visits, and were prescribed a broader range of analgesic drugs in the year post-index than respective controls. Mean healthcare costs of all types were significantly higher in the M-S and severe OA pain cohorts vs controls (total: M-S £2519 vs £1379; severe £3389 vs £1397). Paracetamol (M-S: 40% of patients had at least one prescription; severe: 50%) and strong opioids (34% and 59%) were the analgesics most prescribed to patients with OA pain. In all cohorts, multivariable models showed that a higher age at index, the presence of gout, osteoporosis, type 2 diabetes, or coronary artery disease, significantly contributed towards higher healthcare costs.

Conclusion: In the population of Salford, UK, patients with M-S OA pain had significantly higher annual HCRU and costs compared with matched controls without OA; generally, these were even higher in patients with severe OA pain.

Keywords: Analgesia; Arthroplasty; Chronic pain; England; Healthcare cost; Hospitalisation; Length of stay; Osteoarthritis; Primary health care; Regional health planning.

Fig. 1

Study design. ^aOA diagnosis defined through International Classification of Disease, 10th revision codes or read codes at any time in the patient’s medical history (see Table S1). Note that surgical interventions were assessed in the 2 years post-index; however, this was a secondary analysis, and patients were not required to have 2 years of follow-up. OA osteoarthritis

Fig. 2

Participants. OA osteoarthritis

Fig. 3

Mean HCRU per patient in the 12 months post-index. Number above the bar (+ SD) indicates the mean in the 12 months post-index. All comparisons with the respective control are p < 0.05. Moderate to severe OA pain and matched control cohorts each comprise 3123 patients. Severe OA pain and matched control cohorts each comprise 1922 patients. A&E accident and emergency, GP general practitioner, HCRU healthcare resource utilisation, OA osteoarthritis, SD standard deviation

Fig. 4

Hazard ratio for the risk of OA-related surgical interventions in the cohort of patients with moderate to severe OA pain. Includes 512 first surgical events that took place after the index date for patients with a full set of covariates. Global p = 0.01 from log-rank test. n = 3123 except for comparison groups: female, n = 1903; male, n = 1220; current smoker, n = 518; former smoker, n = 982; never smoked, n = 1198. Data for unknown/missing smoking status not shown (hazard ratio 1.47 vs current smoker; 95% CI 0.20, 10.62). *p < 0.05. BMI body mass index, CCI charlson comorbidity index, CI confidence interval

Fig. 5

Direct healthcare costs in the 12 months post-index. Bar annotations indicate means in the 12-months post-index. All comparisons with the respective control are p < 0.001. Moderate to severe OA pain and matched control cohorts each comprise 3123 patients. Severe OA pain and matched control cohorts each comprise 1922 patients. A&E accident and emergency, GP general practitioner, OA osteoarthritis