Health‐related quality of life and its determinants in pemphigus: a systematic review and meta‐analysis

DEAR EDITOR, The growing interest in exploring the impact of pemphigus on health-related quality of life (HRQoL) is reflected in the increasing number of studies in the area. Two reviews can be found in the literature on HRQoL impairment related to pemphigus; however, neither of them applied a systematic search strategy or meta-analysis. Also, the latest study included was published in 2009. Therefore, the objectives of this paper were to perform a systematic review of the literature on HRQoL in pemphigus, to perform a meta-analysis on the most frequently used instruments, and to identify the possible determinants of HRQoL. We searched in Ovid Medline, Embase, Web of Science, CINAHL, PsycINFO and the Cochrane Library up to 6 October 2014. The search strategy included a combination of terms related to pemphigus, general HRQoL and the names of generic and dermatology-specific instruments. No language limits were applied. Eligible studies were screened by two independent reviewers (F.R. and V.B.), and references were also tracked. Inclusion criteria were (i) the study population included adult patients with pemphigus; (ii) the study reported HRQoL of pemphigus assessed by any instrument (not aggregated results for a group of skin diseases); and (iii) publications were original articles. For all studies the following data were extracted: patient characteristics (sample size, pemphigus type, mean age, disease duration, sex ratio, current therapy and geographical location), applied HRQoL instruments and HRQoL scores. Determinants of general or dermatology-specific HRQoL analysed statistically in the studies were retrieved. For meta-analysis, the number of patients and mean HRQoL scores and SDs were extracted, and 95% confidence intervals (CIs) were calculated. Meta-analysis was performed on Dermatology Life Quality Index (DLQI) total scores or individual domains of HRQoL instruments, on which results were reported in at least three separate studies including patients of similar characteristics. Where significant heterogeneity was detected between studies (Cochran’s Q P < 0 01 or I > 50%), random-effects meta-analysis (inverse-variance method) was applied; otherwise the fixed-effects approach was employed. Sixteen studies from eight different countries were identified assessing HRQoL in 1465 patients with pemphigus with eight different instruments (Table 1). Our systematic search strategy yielded nine further papers published since the former reviews, and two additional studies that were not included in the earlier reviews despite being published before 2009. There were 11 cross-sectional studies, four case–control studies and a prospective cohort with a 4-month follow-up period. The patient populations varied between seven and 380, with only five studies enrolling > 100 participants. Four different generic measures were used: Short Form-36 (SF-36), Activities of Daily Living, World Health Organization Quality of Life-BREF and World Health Organization Disability Assessment Schedule 2.0. Four types of dermatologyor oraldisease-specific tools were applied: DLQI, Skindex-29, Skindex-17 and Chronic Oral Mucosal Diseases Questionnaire. The most frequently used measures were SF-36 (eight of 16), DLQI (five of 16) and Skindex-29 (four of 16). The meta-analysis showed the highest deterioration in the role-physical dimension of SF-36 (38 1, 95% CI 20 4–55 9), followed by role-emotional (47 5, 95% CI 21 9–73 2) and vitality (50 7, 95% CI 43 6–57 7) (Fig. 1a). The mean total DLQI score of patients with pemphigus ranged from 4 0 to 13 8. Newly diagnosed or untreated patients scored on average 12 0 (95% CI 11 1–12 9) (Fig. 1b). The greatest impairments were reported in the symptoms and feelings, and daily activities dimensions of DLQI (2 8–3 0 and 1 9–2 2, respectively). The meta-analysis indicated similar mean scores in the symptoms (35 8, 95% CI 32 7–38 9) and emotions (36 5, 95% CI 33 8–39 2) domains of Skindex-29, whereas they were slightly lower for social functioning (32 8, 95% CI 29 9–35 6) (Fig. 1c). Overall, 41 possible determinants of HRQoL were identified (Table S1; see Supporting Information), of which reduced HRQoL was clearly associated with higher disease severity, anxiety and depression in at least two separate studies. However, the impact of several factors on HRQoL, such as age, sex, type of pemphigus, disease duration, mucocutaneous involvement, clinical activity, itching, skin burning or being treated by adjuvant drugs, cannot be clearly stated. This paper provides the first systematic review and metaanalysis of HRQoL studies in pemphigus. The various HRQoL instruments applied, the different sample sizes and the geographical locations hinder the comparison of the 16 studies. Only five studies used both generic and dermatology-specific measures. The eight different tools capture different aspects of HRQoL and yet do not necessarily explore all the