Nationwide Assessment of Cause-Specific Mortality in Patients with Rosacea: A Cohort Study in Denmark

Background Emerging data suggest that rosacea is associated with several comorbidities; however, the causes of mortality in patients with rosacea have not yet been investigated. Objective We evaluated all-cause and cause-specific death rates in patients with rosacea in a population-based Danish cohort study. Methods All Danish individuals aged aeyen18 years between 1 January 1997 and 31 December 2012 with rosacea diagnosed by hospital dermatologists were linked in nationwide registers and compared with age- and sex-matched general-population subjects (1:5 ratio). Death rates were calculated per 1000 person-years, and hazard ratios (HRs) were estimated using Cox regression models. Results The total cohort (n = 35,958) included 5993 patients with rosacea and 29,965 age- and sex-matched individuals from the general population. During the maximum 15 years of follow-up, 664 (11.1 %) patients with rosacea and 3121 (10.4 %) patients in the reference population died. The risk of all-cause mortality was similar in patients with rosacea and the reference population [HR 1.06, 95 % confidence interval (CI) 0.98-1.15]. Analyses of cause-specific mortality revealed a significantly increased risk of death due to gastrointestinal diseases in patients with rosacea (HR 1.95, 95 % CI 1.31-2.89), primarily related to hepatic disease. No increased risk of death due to other major disease categories, e.g. cancer, cardiovascular, neurological, or infectious diseases was observed. Conclusion We observed a significantly increased risk of death due to gastrointestinal diseases (primarily hepatic disease) in patients with rosacea; however, we found no increased risk of death due to other causes such as cardiovascular or neurological diseases. Although this does not necessarily imply a causal link, the findings underscore the association between rosacea and gastrointestinal disease, but also that rosacea may be associated with increased risk factors, including alcohol consumption.