Measuring benefits of opioid misuse treatment for economic evaluation: health-related quality of life of opioid-dependent individuals and their spouses as assessed by a sample of the US population

Abstract

Aims: To understand how the general public views the quality of life effects of opioid misuse and opioid use disorder on an individual and his/her spouse, measured in terms used in economic evaluations.

Design: Cross-sectional internet survey of a US population-representative respondent panel conducted December 2013-January 2014.

Setting: United States.

Participants: A total of 2054 randomly selected adults; 51.1% male (before weighting).

Measurements: Mean (95% confidence interval) and median health 'utility' for six opioid misuse and treatment outcomes: active injection misuse; active prescription misuse; methadone maintenance therapy at initiation and when stabilized in treatment; and buprenorphine therapy at initiation and when stabilized. Utility is a numerical representation of health-related quality of life used in economic evaluations to 'adjust' estimated survival to include peoples' preferences for health states. Utilities are determined by surveying the general population to estimate the value they assign to particular health states on a scale where 0 = the value of being dead and 1.0 = the value of being in perfect health. Spouse spillover utility is assigned to a spouse of an individual who is in a particular health state.

Findings: Mean individual utility ranged from 0.574 [95% confidence interval (CI) = 0.538, 0.611] for active injection opioid misuse to 0.766 for stabilized buprenorphine therapy (95% CI = 0.738, 0.795), with other states in between. Female respondents assigned higher utility to the active prescription misuse and buprenorphine therapy at initiation states than did males (P < 0.05); all other states did not differ by respondent gender. Mean spousal utilities were significantly lower than 1.0 but mostly higher than individual utility, and were similar between male and female respondents.

Conclusions: In the opinion of the US public, injection opioid misuse results in worse health-related quality of life than prescription misuse, and methadone therapy results in worse health-related quality of life than buprenorphine therapy. Spouses are negatively affected by their partner's opioid misuse and early treatment.

Keywords: Economic evaluation; health-related quality of life; opioid misuse; spillover effects; utilities.