2015 ISAKOS Biennial Congress ePoster #202

The Impact of Psychosocial Factors on Pain Severity in Knee Osteoarthritis

Lauren Anne Eberly, MD, Albuquerque, NM UNITED STATES
Dustin Richter, MD, Albuquerque, NM UNITED STATES
George Comerci, MD, Albuquerque, NM UNITED STATES
Gary Mlady, MD, Albuquerque, NM UNITED STATES
Daniel C. Wascher, MD, Albuquerque, NM UNITED STATES
Robert C. Schenck, Jr., MD, Alburquerque, NM UNITED STATES
University of New Mexico Department of Orthopaedics, Albuquerque, New Mexico, USA

FDA Status Not Applicable

Summary: While objective measures of knee osteoarthrtiis such as Kellgren-Lawrence radiographic severity are not related to a patient's reported pain score, psychosocial and sociodemographic factors are potentially the most important determinants of pain in knee OA and warrant further attention in the management of this disease.

Abstract:

Introduction

Osteoarthritis (OA) is the most common joint disease in the United States, with pain being the primary reason patients seek care. The purpose of this study is to characterize the determinants of patient perception of pain in knee OA, with particular focus on the influence of psychosocial and sociodemographic factors.

Methods

Using selected cpt codes, new patients were identified who presented with a primary diagnosis of knee OA to our institution over a one year period. Patients with ligamentous injury or inflammatory arthritis were excluded, leaving 355 patients who met inclusion criteria. A retrospective chart review identified the numeric pain score based on a 0-to-10 point scoring instrument, baseline demographic information, BMI, substance use history, past medical history, current prescriptions, and insurance status. A radiologist (blinded to the patient pain score) rated severity of knee radiographic OA using the Kellgren-Lawrence (K-L) score. Univariate and multivariate analysis was performed to determine whether a relation existed between the numeric pain score and these variables.

Results

The mean pain score was 5.0. In the univariate analysis, higher pain scores were associated with increased BMI (p<0.001), illicit drug use (p=0.004), current smoking history (p=0.02), and a lack of health insurance (p= 0.01). Patients with a diagnosis of depression (p<0.001) or fibromyalgia (p=0.003) reported higher pain scores. Current opioid (p<0.001), gamma-aminobutyric acid (GABA) analog (p<0.001), or anti-depressant (p<0.005) prescription were all associated with higher pain scores. There was also a statistically significant relationship between ethnicity and pain score (p=0.0005), with higher pain scores in the Hispanic and Native American populations. Gender was not associated with differences in pain score (p=0.86), and there was no statistically significant relationship between pain score and radiographic OA severity [K-L score (p= 0.2)]. Depression, current opioid prescription, and ethnicity retained a significant association with pain scores in the multivariate analysis.

Conclusion

Pain in knee OA is multifactorial. Our results in a large, ethnically diverse cohort indicate that while objective measures such as K-L scores are not related to pain severity, psychosocial and sociodemographic factors are potentially the most important determinants of pain in knee OA and warrant further attention in the management of this disease.