Psoriasis Causes Significant Economic Burden to Patients

Psoriasis is a common chronic inflammatory disease with a prevalence of 1.5–2.8% worldwide [1, 2]. Around 6–30% of patients with psoriasis also have psoriatic arthritis [3‐5]. Psoriasis is a lifelong disease thus leading to considerable burden and expenses [1, 6]. When assessing the health economic consequences of a disease, the perspective of patients is considered important [1, 7].

Psoriasis results in expenses to patients from many cost sources mainly because of medications, topical emollients and balneotherapy [8‐12]. Some psoriasis treatments (mainly phototherapy) are given in hospitals, usually in as a course of treatment, so considerable time and traveling costs can be expected [7, 11, 13]. Studies have estimated that patients have to spend a lot of time each day in home care of psoriasis, but the results have wide variations [11, 12]. Psoriasis also increases the need for cleaning and laundry, and increases the need for assistance at home [11].

Psoriasis has no known curative treatment; therapy aims to reduce symptoms and gain quality of life. Topical steroids and vitamin D analogs are shown to be the most commonly used treatment method [5]. Phototherapy and/or systemic medications are combined if necessary [5]. Countries have varying social/private insurance systems, thus the costs of medications for the patients varies.

The aim of this study was to evaluate the multidimensional economic burden of psoriasis to patients.

The patients had relatively low psoriasis severity (Table 1). The total costs to patients were higher for those receiving traditional systemic medications than not receiving systemic medications (Table 2). Medicine costs, skin care cost and costs of assistance for household chores comprised most of the differences (Table 2). Visit costs were higher for patients not receiving traditional systemic medications, mainly because their costs of phototherapy (217 euro, SD 358) were higher (p < 0.001) than for those who received systemic medications (82 euro, SD 228).

Medications and phototherapy formed 18% of the total economic burden for a patient. Phototherapy and biologic medications (527 euro, SD 280, n = 14) were the costliest therapies for a patient to receive. Travel costs and travel time costs comprised over 60% of the costs of phototherapy (Table 3). Patients receiving phototherapy lived on average 10 km closer to TUH than those who did not receive phototherapy (p < 0.05).

A majority of the total visit costs incurred by patients were from visiting TUH and only a small proportion from visiting all primary health care providers (Table 4). Patients with psoriatic arthritis received more phototherapy and had more visits, thus had higher visiting costs than patients with psoriasis (Table 4). Patients with more severe psoriasis (PASI >5.5) had higher (p < 0.05) total visiting costs (673 euro, SD 848) than patients with less severe psoriasis (PASI ≤5.5) (359 euro, SD 369). Patients who received phototherapy had higher (p < 0.001) total visiting costs (673 euro, SD 658) than the patients who did not receive phototherapy (234 euro, SD 310).

Skin care time (Table 1) was estimated to correspond to almost half of the total economic burden to the patient (Table 2). Patients receiving traditional systemic medications had higher costs for skin care than those who did not (Table 2). Sex, age, diagnosis, the severity of psoriasis or receiving phototherapy did not have a statistically significant effect on skin care costs. A quarter of the study group received assistance for household chores because of psoriasis. For the patients who received assistance, the estimated annual cost was 1,014 euro (SD 1,131).

There is little information concerning the costs of psoriasis incurred by patients. In this study, the co-payments for visits to hospital and for medications and emollients comprised only a minority of the total costs for a patient, while travel costs and lost time were estimated to contribute the majority of the costs to patients. In a recent study in Spain [15], the relationship of travel costs and time costs were similar from the patients’ perspective.

Phototherapy has been estimated to be costly for patients [2, 7, 8, 11]. In this study, biologic therapy and phototherapy had almost equal costs to patients. In studies in the US, lower out-of-pocket costs for patients have been estimated to have led to favoring biologic therapies over phototherapy [16, 17]. This can lead to higher total costs for the society of psoriasis treatment as phototherapy has been estimated to be the most cost-efficient, or one of the most cost-efficient, treatment methods of psoriasis [18‐20]. However, travel costs and travel time costs are rarely included in cost estimations of psoriasis treatments [16, 19‐21], which may have led to underestimation of the actual costs of phototherapy. The current sample included all patients visiting the clinic during 1 year. Thus, all types of phototherapy patients can be assumed to be represented, those in remission as well as those in active treatment; and the costs were based on the actual number of visits during the whole year.

In this study the indirect costs were estimated to comprise the majority of costs of phototherapy for the patients. Earlier studies have estimated that travel costs account for around two-thirds of the total costs of phototherapy [22]. Time lost because of phototherapy has been estimated to be around 110 min/treatment session [22] or take 33 h per year [11]. It has been reported that, from the perspective of patients, travel distance plays a major role in treatment selection [23]. Loss of time, whether working or leisure time, has value to the patients, irrespective of the lost earnings. In this study, the aim was to analyze the burden of the disease to a patient, not to employers, or the society as a whole. Thus, possible productivity losses from absenteeism or presenteeism were not included.

A recent study suggests that patients living further away from UV-treatment facility have lower dermatology life quality index (DLQI) and suffer from lack of treatment [23]. The current study indicated that patients living further away from tertiary level hospital receive less phototherapy, which may be due, in part, to the decisions made by patients and not just the decisions made by treatment providers. Studies are required to determine if patients living further away from service provider suffer from under treatment. Home phototherapy is rarely used in our study area although it seems that, at least for patients living further away from the service provider, it could increase treatment options.

In some earlier studies [16], medication costs were estimated using average prices and average weekly doses. This can be a source for potential overestimates of medication costs as a considerable proportion of psoriasis patients do not necessarily use the medications as prescribed [24]. In the study all medicine and emollient costs were based on reimbursement data of all purchases, irrespective of who had prescribed the medications, which can be expected to produce more reliable medication cost estimates. Countries have varying social security systems and reimbursement rates so direct comparison between studies has been considered problematic [7, 12, 25]. For example, in this study setting, the cut-off level for complete medicine cost reimbursement was based on national policy. Thus, the medication costs to patients in this study may not be directly generalizable to other countries.

As in this study, earlier studies [8, 19] have shown that patients receiving systemic medications and/or phototherapy have higher costs than those who were receiving only topical treatment. Patients with systemic medication or phototherapy also have been estimated to have lower quality of life and a higher likelihood of treatment failure than other patients [19, 26]. In some studies, patients receiving systemic medication or phototherapy have been classified as having severe psoriasis no matter what PASI scores they had [11, 13]. On the other hand, patients receiving systemic treatment or phototherapy have been found to have lower PASI values than other patients [8], possibly due to successful control of psoriasis in patients receiving adequate treatment. In the authors’ previous work [27] topical therapies were most often combined with other forms of treatment. More severe psoriasis patients, who receive systemic medications to control their symptoms, may need more extensive self-care than those who manage with less care, irrespective of PASI values. These issues could explain why, in this study, almost all costs were higher for patients using systemic medications or phototherapy even though the severity of psoriasis was almost the same. However, in our study only 72 patients had PASI values in their medical records, so analyses with PASI values are not as generalizable as other results and should be treated with more caution.

The primary provider of treatment for patients with psoriasis varies between countries [28]. In most studies patients have been treated mainly by dermatologists [28, 29], as in this study. In Finland, patients with well managed and mild psoriasis are usually treated by general practitioners, with referral to a tertiary level dermatological clinic when exacerbations occur. This may have led to selection bias in the sample as only patients from the dermatological clinic were included.

The current study corroborates earlier studies [8, 11, 13, 30] that time devoted to skin care, household chores and assistance for household chores imposes a considerable burden to patients with psoriasis. The estimates for time used for skin care/topical treatment in previous studies, have had a wide range from 4 min/daily [11] to 57.5 min daily [8]. In this study, the use of two different questions regarding skin care—one estimating the time needed for skin care due to psoriasis and one for the hypothetical time needed for skin care if the patient did not have psoriasis, may have produced more reliable results on time needed due to psoriasis. The study suggests that the time devoted to skin care is a considerable burden, contributing to almost half of the total costs for the patient. Laundry and cleaning seemed to have minor role in costs for the patient, with the majority of patients reporting negligible impact of psoriasis. For those needing assistance, it may form a considerable cost burden.

Information concerning the costs of psoriasis from the perspective of patients is still limited. In this study, the co-payments for visits to hospital and for treatments were estimated to play a minor role in the total costs for a patient, with travel costs and lost time contributing most of the costs. These indirect costs of treatments should not be omitted in future studies as they can be a significant factor when choosing treatments, especially for the patients with psoriasis.