Cost of illness analysis: Hidradenitis suppurativa

Introduction: Hidradenitis Suppurativa (HS) is defined as chronic, inflammatory, recurring, debilitating skin disease of the hair follicles that usually presents after puberty with painful, deep-seated, inflamed lesions in the apocrine gland-bearing areas of the body, most commonly the axillae, inguinal and anogenital regions and also known as Acne Inversa. Due to the few studies regarding economic burden of HS on patients were conducted up to now in US, Europe and Israel, it is inevitable to prepare such a project in the context of HS disease for Turkey. To the best of our knowledge, there has not been any HS cost of illness (CoI) study conducted in Turkey. Therefore, the aim of this study is to estimate the yearly cost of HS disease in Turkey with the perspective of the Turkish Ministry of Health. Material and Methods: This is a prevalence-based CoI study in focus on direct health care costs with the perspective of Ministry of Health which means the payer. A multipoint data collection procedure has been done based on the literature search regarding HS epidemiological data, treatment choices and direct health care costs in order to obtain the necessary data for the analysis and the structure of CoI of HS. A literature search on studies published in English on HS was performed in PubMed with the key words of "Hidradenitis Suppurativa", "Acne Inversa" and "Verneuil Disease" from 1949 to November 2017. Disease itself and treatment options have been reviewed comprehensively. Results: Total numbers of Turkish people with HS has been estimated as 79.815 according to 0.10 % prevalence rate of Garg and his colleagues' prevalence study. The 12 months cost were estimated as 20.807.609,17 TRY (+/- 1.040.380,46 TRY)for patients on Hurley stage I, 622.988.590,40 TRY (+/- 31.149.429,52 TRY) for Hurley stage II and 88.681.664,65 TRY (+/- 4.434.083,23 TRY) for Hurley stage III for the year 2017. We estimated the total direct cost attributable to HS as 732.477.864,22 TRY (+/-36.623.893,21 TRY) and revealed that average one-year direct cost per patient was 9.177 TRY (+/- 458 TRY) which can translated as 192.757.332,69 USD (+/- 9.637.866,63 USD) and 2.415 USD (+/- 120 USD) respectively.. Discussion and Conclusions: Medications seem to be only the definitive important resources funded by the Turkish public health system. Even though the studies' methods are different, it is possible to compare the results of other available HS CoI studies with our study. Cost per patient seems similar between the studies but source and the proportions of the costs were different. Even though HS is a disease which attributed as 'rare' and 'unknown', it is surprising that it takes an important place in terms of treatment costs.