Background Emotional writing is a short-term psychological intervention that has been successfully used in several controlled studies.
Objectives The overall objective of the study was to test the efficacy of Pennebaker’s emotional writing intervention in patients with psoriasis treated with systemic therapy.
Methods A randomized controlled trial was conducted in seven clinical centres in Italy, over a 2-year period. The main outcome measures were the psoriasis area and severity index and the Physician Global Assessment, as well as generic and dermatology-specific quality of life questionnaires. Such outcomes were measured at 4 weeks, and 6 and 12 months from baseline. The project recruitment time was 12 months, and the total follow-up time for each individual was also 12 months.
Results In total, 202 patients were enrolled and assessed at baseline, 67 of whom completed all three follow-up visits. The writing exercise had little or no effect on patients with psoriasis who were undergoing systemic treatment. In the Generalized Estimating Equations models no statistically significant differences were observed in the Pennebaker intervention group vs. the control group. In subgroup analysis for health status, small effects in favour of patients assigned to the Pennebaker group were documented at the end of the study in women, in overweight individuals, in patients under treatment with biological drugs, and on the Physical Component Summary of the Short Form of the Medical Outcomes Study Questionnaire.
Conclusions The Pennebaker and control groups had similar changes over time for practically all the outcome variables, and also when considering all observations and adjusting for all the variables of interest. The longitudinal analysis confirmed that the intervention had little or no effect on the variables of interest. The implementation of writing exercises requires a careful and ad hoc organization, including dedicated spaces for the writing itself.