The Burden of Pain Associated with Osteoarthritis in the Hip or Knee from the Patient's Perspective: A Multinational Cross-Sectional Study

Abstract

Introduction: To evaluate, from the patient's perspective, the burden of pain associated with hip/knee osteoarthritis (OA) in the USA and selected European Union (EU) countries.

Methods: Data were drawn from the 2017 global Adelphi OA Disease Specific Programme™ (DSP). Patients with hip/knee OA were stratified based on pain intensity and the presence/absence of current opioid use. Outcomes included Western Ontario and McMaster Universities Osteoarthritis Index scores, functional limitations, unmet treatment needs, Charlson Comorbidity Index, relevant comorbid conditions, the 5-dimension 5-level EuroQol, and the Work Productivity and Activity Impairment Questionnaire: Specific Health Problem. Bivariate testing compared outcomes using patients with no/mild pain without opioid use as the reference group.

Results: The study population comprised 2170 patients (US: n = 623 [28.7%]; EU: n = 1547 [71.3%]) with knee (54.9%), hip (24.6%), or knee/hip (20.5%) OA. Mean (SD) age was 66.4 (11.2) years. Patients had no/mild pain without opioid use (39.6%), no/mild pain with opioid use (10.2%), moderate/severe pain without opioid use (30.6%), and moderate/severe pain with opioid use (19.7%). Compared with the reference group, patients with moderate/severe pain reported significantly (p < 0.05) higher functional limitations, greater use of ≥ 3 treatments and treatment dissatisfaction, reduced quality of life, and impaired work productivity and activity. The burden was highest with moderate/severe pain with opioid use. Results were generally similar in the US and EU cohorts.

Conclusions: The results from this multinational cross-sectional study indicate that the impact of OA pain is multidimensional, worsened by increasing pain intensity, and may not be adequately addressed by current treatment strategies.

Keywords: Comorbidity; Daily activity; Health-related quality of life; Opioid; Osteoarthritis; Pain; Physical functioning; Work productivity.

Fig. 1

WOMAC scores in patients with hip and/or knee OA by pain intensity and opioid use. a Physical function scores. b Stiffness scores. Scale ranges from 0 to 10, with higher scores indicating worse condition. ^ap < 0.05 versus no/mild pain without opioid use. EU European Union, OA osteoarthritis, SD standard deviation, WOMAC Western Ontario and McMaster Universities Osteoarthritis Index

Fig. 2

CCI scores in patients with hip and/or knee OA by pain intensity and opioid use. ^ap < 0.05 versus no/mild pain without opioid use. CCI Charlson Comorbidity Index, EU European Union, OA osteoarthritis, SD standard deviation

Fig. 3

EQ-5D-5L scores in patients with hip and/or knee OA by pain intensity and opioid use. a VAS scores. b Utility index scores. Higher scores indicate better quality of life. ^ap < 0.05 versus no/mild pain without opioid use. EQ-5D-5L 5-dimension 5-level EuroQol, EU European Union, OA osteoarthritis, SD standard deviation, VAS visual analog scale

Fig. 4

WPAI:SHP scores in patients with hip and/or knee OA by pain intensity and opioid use. a Percentage of work time missed. b Percentage of impairment while working. c Percentage of overall work impairment. d Percentage of activity impairment. Activity impairment was assessed among all patients; work productivity was assessed among employed patients only. ^ap < 0.05 versus no/mild pain without opioid use. ^bAbsenteeism. ^cPresenteeism. EU European Union, OA osteoarthritis, SD standard deviation, WPAI:SHP Work Productivity and Activity Impairment Questionnaire: Specific Health Problem