Background: Psoriasis causes considerable patient morbidity and can seriously affect a patient's quality of life (QoL).
Objectives: To investigate the relationships between changes in QoL and measures of severity and extent of disease, and itch, in patients with chronic plaque psoriasis receiving intermittent short courses of cyclosporin (Neoral).
Methods: This study was performed as part of an international trial investigating the safety, efficacy and total costs of intermittent short courses of cyclosporin (the PISCES study). All patients received cyclosporin until clearance and were then followed up until relapse. On relapsing, patients received another course. Patients were followed up for a minimum of 1 year during which they could receive as many courses of treatment as necessary. In a subgroup (n = 255) of patients in the trial, the Dermatology Life Quality Index (DLQI) was used to assess the impact of psoriasis and its treatment on the patients' health status at the beginning and end of each treatment period. At the beginning and end of each treatment period, as well as at 2-weekly visits, the extent and severity of disease, together calculated into a modified Psoriasis Area and Severity Index (PASI), and itch were recorded. Data were analysed using the Wilcoxon matched pairs test, multivariate Hotelling's T2 tests, and Spearman's rank correlation coefficients (rs).
Results: During treatment, a clear impact on the overall DLQI scores and in the scores in all six DLQI headings was found (i.e. an improvement in QoL; P < 0.001 in all scores). Also, significant decreases in PASI and itch scores were found (P < 0.001). Multivariate analyses confirmed that a decrease in PASI and itch scores was accompanied by an impact on the DLQI scores during and between the two treatment periods (P < 0.0001). Statistically significant but weak correlations were found between changes in QoL and changes in PASI (rs = 0.40 and 0.24 for the first and second treatment periods, respectively) and itch scores (rs = 0.31 and 0.42, respectively).
Conclusions: Intermittent short courses of cyclosporin clearly improve the QoL of the patients and decrease the extent and severity of disease and itch. Changes in clinical outcome scores are accompanied by changes in QoL. The weak correlations between changes in QoL and clinical measures may suggest that no clear relationship between QoL and clinical outcomes exists. However, due to the inclusion and exclusion criteria of the study, both QoL and clinical outcome measures do not show much variation among this homogeneous group of patients. As long as the relationship between clinical outcome parameters and measures of QoL is not completely clear, both measures of health should be considered in adequate, patient-orientated clinical decision making.