Figure 10.

Adjusted average annualized cost per PTPS NeP subject, overall and by average pain severity.^a

Notes: ^aScores on the BPI-SF Pain Severity were used to classify average pain severity as follows: 0–3 represents mild pain, 4–6 represents moderate pain, and 7–10 represents severe pain; ^baverage annualized total direct cost per subject was significantly different by pain severity (P < 0.0001). Direct costs include physician visits, other health care provider visits, prescription medications, TENS device, outpatient tests/procedures, emergency room visits, hospital outpatient visits, hospitalizations, direct medical costs to subjects, and direct nonmedical costs (child care, help with house and/or yard work, and help with activities of daily living) due to PTPS NeP. ^cAverage annualized total indirect cost per subject was significantly different by pain severity (P < 0.0001). Total indirect costs include overall work impairment, activity impairment, disability, unemployment, early retirement, and reduced work schedule due to PTPS NeP. ^dAdjusted LS mean estimates from multiple linear regression adjusted for confounding demographic and clinical variables – specifically, covariates for direct costs: ethnicity, pain severity (mild/moderate/severe only), prescription coverage, and comorbidities (headache/migraine, major depressive disorder, irritable bowel syndrome, cognitive dysfunction, chronic fatigue syndrome [overall only], sleep disturbance/insomnia, chronic low back pain, and other); and for indirect costs: age, race, pain severity, and comorbidities (major depressive disorder and irritable bowel syndrome).

Abbreviations: PTPS, post-traumatic/post-surgical; NeP, neuropathic pain; BPI-SF, Brief Pain Inventory-Short Form; TENS, transcutaneous electrical nerve stimulation; LS, least squares.