A growing number of clinical trials of biological and systemic therapies have been conducted within adult atopic dermatitis (AD). No study has yet examined and meta-analysed the pooled placebo response in AD. We performed a systematic review and meta-analysis to examine the placebo response in clinical trials evaluating the effect of systemic and biological therapies in adult AD and compared it to results from clinical trials in psoriasis. Two screeners independently searched the databases ClinicalTrials.gov, Embase, Pubmed and Web of Science. A total of 2058 articles were identified, of which 78 were full-text reviewed. Overall, 25 trials were included in the qualitative analysis, of which 24 were further included in the quantitative analysis. At 12-week follow-up, EASI50, EASI75 and EASI90 placebo responses were 39.9% [95% confidence interval (CI), 36.7-43.2], 20.9% (95% CI, 18.2-23.8) and 9.0% (95% CI, 6.7-11.6), respectively. At week 12, the pooled proportion of placebo-treated AD patients that obtained EASI50, EASI75 and EASI90 was significantly higher than the pooled proportion of placebo-treated psoriasis patients obtaining PASI50, PASI75 and PASI90 (P < 0.05). Our findings emphasize the fluctuating nature of AD and show that correct and consistent use of topical treatments strongly reduces disease severity.

IMPORTANCEFour distinct rosacea subtypes have traditionally been recognized, but the frequency of these subtypes among patients with rosacea remains unknown.OBJECTIVE To assess the frequency of 4 rosacea subtypes.DATA SOURCES This systemic review and meta-analysis included a search of 2 databases, PubMed and Embase, from inception of the databases to November 2, 2021. The search was filtered to include only studies of human participants published in English, French, and German.STUDY SELECTION Studies were screened independently by 2 of the authors and were included if they were original with a sample size of 25 or more patients and reported absolute numbers or frequency of patients affected by rosacea subtypes. Studies that did not report sufficient data to calculate the proportions of subtypes were excluded. DATA EXTRACTION AND SYNTHESISData extraction was performed independently and in duplicate by 2 of the authors, using the search term rosacea, according to the Preferred Reporting items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The search term, objectives, and study protocol methods were defined before the study was initiated. A total of 292 studies were included for full-text assessment. Owing to the heterogeneity of the included studies, a random-effects model was used. MAIN OUTCOME AND MEASURESThe main outcome was the proportion of patients with rosacea in each of the 4 major subtype groups defined by the 2002 National Rosacea Society classification system. Measures were absolute numbers or frequency of patients affected by each of the 4 rosacea subtypes.RESULTS A total of 39 studies examining 9190 patients with rosacea were included. The pooled proportion of erythematotelangiectatic rosacea was 56.7% (95% CI, 51.4%-62.0%), of papulopustular rosacea was 43.2% (95% CI, 38.8%-47.6%), of phymatous rosacea was 7.4% (95% CI, 6.1%-8.9%), and of ocular rosacea was 11.1% (95% CI, 6.7%-16.3%). Subtype distribution occurred equally among men and women except for phymatous rosacea, which was more prevalent in men. Studies from Africa showed the lowest proportion of erythematotelangiectatic rosacea. Differences in frequency of subtypes were observed when stratification by publication year was performed. CONCLUSION AND RELEVANCEIn this systematic review and meta-analysis, differences were found in rosacea subtypes by patient sex and by continent of origin and publication year of included studies. Erythematotelangiectatic and papulopustular rosacea were the most prevalent subtypes, but data should be interpreted with caution. Future studies should use the phenotype-based rosacea approach.

GI transit times and colonic volumes were not correlated to self-reported GI symptoms even in a controlled experimental study and when symptoms were categorized into relevant symptom groups. Thus, both subjective and objective measures must be considered relevant when assessing constipation in clinical and research settings, ensuring that both physiological aspects as well as the severity and impact of symptoms experienced by patients can be assessed.