Disease burden of patients with pemphigus from a societal perspective.

Introduction: Cost-of-illness studies are widely used for healthcare decision-making; however, no such study is available in pemphigus from the societal perspective. The purpose of this analysis was to estimate annual cost-of-illness per patient with pemphigus from a societal perspective. Areas covered: Between 2014 and 2017, a multicenter, cross-sectional study was carried out. Consecutive pemphigus patients aged ≥18 years were recruited at all four university dermatology departments in Hungary. Direct and indirect costs were calculated, including costs for treatments, outpatient visits, hospital admissions, informal care, travel costs and productivity loss. Generalized linear model was used to analyze predictors of costs. Atotal of 109 patients with pemphigus enrolled with amean age of 57.1 (SD 14.8) years. Total cost per pemphigus patient was €3,995 (SD €7,526) peryear, with productivity loss (58%) and informal care (19%) accounting for the majority. Annual means of 189 and 41 working hours were lost due to absence from work and reduced productivity, respectively. Younger age and pemphigus vulgaris were associated with higher costs (p < 0.05). Expert opinion: This is the first cost-of-illness study applying the societal perspective in pemphigus. Our results indicate a substantial economic burden on society, mainly driven by productivity loss and informal care.

DLQI-R scoring improves the discriminatory power of the Dermatology Life Quality Index in patients with psoriasis, pemphigus and morphea.

BACKGROUND: The Dermatology Life Quality Index (DLQI) rates 'not relevant' responses (NRRs) as the item on the questionnaire having no impact on the patients' lives at all. The DLQI-Relevant (DLQI-R) is a recently developed scoring that adjusts the total score of the questionnaire for the number of NRRs indicated by a patient. OBJECTIVES: To compare the discriminatory power of the original and DLQI-R scoring approaches in terms of absolute and relative informativity. METHODS: Cross-sectional data from 637 patients with morphea, pemphigus and psoriasis were used for the analyses. To assess absolute and relative informativity, Shannon's index and Shannon's evenness index were calculated for the 10 items on the questionnaire and for DLQI and DLQI-R total scores. RESULTS: Mean DLQI and DLQI-R scores of patients were 6·13 vs. 6·91. In the subset of patients with NRRs (n = 261, 41%), absolute informativity was higher with the DLQI-R scoring for all eight items with NRR options in all three conditions. The DLQI-R exhibited a better relative informativity in 8, 8 and 6 items in pemphigus, morphea and psoriasis, respectively. The DLQI-R led to an improvement in average item-level informativity in all DLQI score bands up to 20 points. Regarding total scores, the DLQI-R produced both a higher absolute and relative informativity in all three conditions. CONCLUSIONS: In patients with morphea, pemphigus and psoriasis, DLQI-R scoring improves the discriminatory power of the questionnaire by benefiting from the additional information in NRRs. DLQI-R scoring may be useful both in clinical practice and research. A scoring chart has been developed to aid physicians with scoring. What's already known about this topic? The original scoring of the Dermatology Life Quality Index (DLQI) rates 'not relevant' responses as the item of the questionnaire having no impact on the patients' lives at all. DLQI-Relevant (DLQI-R) is a new scoring developed in 2018 that adjusts the total score of the questionnaire for the number of 'not relevant' responses indicated by patients. The discriminatory power of the DLQI-R compared with the DLQI has not yet been investigated. What does this study add? In patients with psoriasis, pemphigus and morphea, DLQI-R scoring improves the discriminatory power of the questionnaire by benefiting from the additional information in 'not relevant' responses. What are the clinical implications of this work? DLQI-R scoring may help to more accurately quantify patients' health-related quality of life both in clinical practice and research. A scoring chart has been developed to aid physicians with scoring.

Patient-assigned health utility values for controlled and uncontrolled pemphigus vulgaris and foliaceus.

BACKGROUND: The assessment of health-related quality of life (HRQoL) in patients with pemphigus is now of increasing interest due to the availability of highly effective new therapies. Preference-based HRQoL values or health utilities required for medical and financial decision-making are not yet available directly from pemphigus patients. OBJECTIVE: To obtain health utility values for current health and hypothetical health states from the perspective of pemphigus patients. METHODS: A cross-sectional questionnaire survey was carried out with pemphigus patients. Disease severity was rated by Autoimmune Bullous Skin Disorder Intensity Score (ABSIS). Patients were asked to evaluate their current health as well as three common hypothetical pemphigus health states [uncontrolled pemphigus vulgaris (PV), uncontrolled pemphigus foliaceus (PF) and controlled PV/PF] by using composite time trade-off (cTTO). Multiple regression was applied to explore determinants of utility values. RESULTS: Responses of 108 patients (64.8% women, mean age 57.4 years) were analysed. Mean ABSIS score was 11.6. The mean utility values for the hypothetical uncontrolled PV, uncontrolled PF and controlled PV/PF health states were 0.41, 0.52 and 0.66 with cTTO. The mean cTTO scores for current health were higher compared with the hypothetical health states (0.76; P < 0.001). Patients with higher ABSIS, worse pain intensity scores and those having a caregiver reported lower utility values for current health (P < 0.05). CONCLUSIONS: In pemphigus, HRQoL impairment expressed in utility values seems to be considerable, especially in comparison with other chronic dermatological conditions (e.g. psoriasis, atopic eczema, chronic hand eczema). These health utilities inform physicians, policymakers and funders about the overall extent of health loss in pemphigus and provide evidence to guide medical decisions and cost-effectiveness analyses of treatment strategies. Future research is needed to evaluate the caregiver burden in pemphigus.

Validity of the EQ-5D in patients with pemphigus vulgaris and pemphigus foliaceus.

BACKGROUND: No studies to date have employed the EuroQoL EQ-5D questionnaire to assess health-related quality of life (HRQoL) in patients with pemphigus. OBJECTIVES: To evaluate the HRQoL of patients with pemphigus by the EQ-5D and to analyse the convergent and known-groups validity of the EQ-5D in this patient population. METHODS: Between 2014 and 2017, a multicentre cross-sectional study was carried out. Outcome measures included the five-level EQ-5D (EQ-5D-5L), Dermatology Life Quality Index (DLQI), Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) and an average pain intensity visual analogue scale (VAS) for the past 3 months. RESULTS: In total, 109 consecutive patients with pemphigus participated in the study (mean age 57 years; 64% women). Among the EQ-5D dimensions, the most problems were reported regarding pain/discomfort (50%), mobility (43%) and anxiety/depression (43%). No significant difference was found in mean EQ-5D index scores between patients with pemphigus vulgaris and those with pemphigus foliaceus (0·81 vs. 0·86, P = 0·14). The mean EQ-5D index scores of patients with limited, moderate, significant and extreme pemphigus were 0·88, 0·82, 0·72 and 0·67, respectively (P = 0·001). The number of comorbidities was associated with greater impairment in EQ-5D index scores (P < 0·001). DLQI (rs = -0·62, P < 0·001) and the average pain intensity VAS (rs = -0·59, P < 0·001) more strongly correlated with the EQ-5D index scores than did ABSIS (rs = -0·40, P < 0·001). CONCLUSIONS: This is the first study employing the EQ-5D questionnaire in pemphigus. The EQ-5D is a valid measure of HRQoL in patients with pemphigus that can be useful both in clinical practice and in economic evaluations to assess the health gains associated with new effective treatments.

Valuation of pemphigus vulgaris and pemphigus foliaceus health states: a convenience sample experiment.

BACKGROUND: Health-related quality of life (HRQoL) in pemphigus has been widely investigated; nevertheless, utility values for economic evaluations are still lacking. OBJECTIVES: To estimate health utilities for hypothetical pemphigus vulgaris (PV) and pemphigus foliaceus (PF) health states in a general population sample. METHODS: Three health states (uncontrolled PV, uncontrolled PF and controlled pemphigus) were developed based on a systematic literature review of HRQoL studies in pemphigus. Utilities were obtained from a convenience sample of 108 adults using a visual analogue scale (VAS) and 10-year time trade-off (TTO). Lead-time TTO was applied for health states regarded as worse than dead with a lead time to disease time ratio of 1 : 1. RESULTS: The mean VAS utility scores for PV, PF and controlled pemphigus were 0·25 ± 0·15, 0·37 ± 0·17 and 0·63 ± 0·16, respectively. Corresponding TTO utilities were as follows: 0·34 ± 0·38, 0·51 ± 0·32 and 0·75 ± 0·31. Overall, 14% and 6% judged PV and PF as being worse than dead. For both VAS and TTO values, significant differences were observed between all health states (P < 0·001). VAS utilities were rated significantly lower compared with TTO in each health state (P < 0·001). CONCLUSIONS: This is the first study that reports health utility values for PV and PF. Successful treatment of pemphigus might result in significant utility gain (0·24-0·41). These empirical findings with respect to three health states in pemphigus may serve as anchor points for further utility studies and cost-effectiveness analyses.