Objective: To analyse the association of direct and indirect costs in patients with medically unexplained symptoms (MUS) with somatic symptom severity (SSS).
Methods: A cross-sectional cost analysis for retrospective 6 months was conducted in 294 primary care patients with MUS. Health care utilisation and loss of productivity were measured by questionnaires. SSS was measured using the "Patient Health Questionnaire 15" (PHQ-15). Direct and indirect costs and the association of costs with SSS were analysed via multiple linear regression analysis.
Results: Patients with MUS had average 6-month direct costs of 1098 EUR and indirect costs of 7645 EUR. For direct costs, outpatient physician visits were the most expensive single cost category (36%), followed by pharmaceuticals (25%) and hospital stays (19%). Indirect costs were predominantly caused by productivity reduction at work (56%) followed by early retirement (29%) and acute sickness absence (14%). As compared to mild SSS, moderate SSS was not significantly associated with direct, but with indirect costs (+2948 EUR; p<.001); severe SSS was associated with increased direct cost (+658 EUR; p=.001) and increased indirect costs (+4630 EUR; p<.001). Age was positively associated with direct cost (+15 EUR for each additional year; p=.015) as well as indirect cost (+104 EUR for each additional year; p<.001).
Conclusions: MUS are associated with relevant direct and even much higher indirect costs that strongly depend on SSS.
Keywords: Direct cost; Indirect cost; Medically unexplained symptoms; Somatic symptom severity; Somatoform disorder.