Analysis of health-related quality of life and costs based on a randomised clinical trial of escitalopram for relapse prevention in patients with generalised social anxiety disorder

BACKGROUND Social anxiety disorder (SAD) is associated with substantial reduction in health-related quality of life (HRQoL). Escitalopram has proven efficacy in the short-term treatment of SAD and prevention of relapse. OBJECTIVES To determine whether the clinical effects of treatment translated into HRQoL benefits and to investigate costs of SAD treatment. METHODS Data on HRQoL and resource utilisation were collected in a previously published clinical trial of escitalopram in relapse prevention. Among 517 patients, 371 responded to 12 weeks of open-label treatment with escitalopram and were randomised to escitalopram or placebo for 24 weeks. HRQoL was assessed using the short form (SF)-36 instrument and SF-6D utilities (preference-based index scores for overall HRQoL) were calculated. Costs were calculated for responders over the acute phase and for non-relapsed patients over the continuation phase, applying UK unit costs. RESULTS Health-related quality of life was significantly improved after the acute phase when compared with baseline. The SF-6D utility increased by 0.047 in responders (p < 0.0001) and 0.021 in non-responders (p = 0.0005). Healthcare costs were non-significantly lower in acute phase than during prestudy phase (p = 0.0587 from NHS perspective), as were productivity costs (p = 0.1440). HRQoL at last visit was lower in relapsed than non-relapsed patients. The difference in utility was -0.026 (p = 0.0007). Healthcare and productivity costs were non-significantly lower in the escitalopram group than in the placebo group. CONCLUSIONS Both effective acute treatment of SAD and prevention of relapse with escitalopram are associated with significant HRQoL benefits. Despite some limitations, the cost analysis suggests that savings in physician-visits and inpatient care may offset drug acquisition costs.