Explaining The Excess Healthcare Expenditures Associated With Chronic Pain Among Adults With Osteoarthritis: An Application Of Cost Decomposition Analysis

Osteoarthritis (OA) is one of the leading causes of chronic pain that interferes with normal daily activities. Pain Interference with Activity (PIA) and OA are associated with high healthcare expenditures. There is a lack of studies on the evaluation of excess healthcare expenditures of PIA in adults with OA. This study estimated the extent to which differences in characteristics among adults experiencing PIA explain excess expenditures associated with OA. This study adopted a cross-sectional design using 2015 data from the Medical Expenditure Panel Survey (MEPS). Adults 21 years or older who were alive during the calendar year and did not have missing information on PIA status were included in the study (N = 1,849; weighted N = 25.43 million). Total healthcare expenditures included inpatient, outpatient, prescription drugs, dental, vision, home healthcare, and other services. The Blinder-Oaxaca post-linear decomposition on log-transformed total health expenditures was used. All analyses accounted for the complex survey design of MEPS. OA adults with PIA had higher average expenditures ($18,902 vs $8,277, p<0.001; 8.84 vs 7.99 in log-transformed expenditures) compared to those without PIA. Based on pooled regression weights, 60% of excess expenditures were explained by differences in characteristics between the two groups. Number of co-occurring chronic health conditions (diabetes, asthma, chronic obstructive pulmonary disease, anxiety, depression and heart diseases) and prescription medications (NSAIDs, opioids, and polypharmacy) were the main drivers of excess healthcare expenditures of PIA. Our findings suggest that primary, secondary, and tertiary prevention of co-occurring chronic health conditions may be a pathway to reducing excess healthcare expenditures associated with chronic pain in adults with OA.