Patients with severe psoriasis have an increased risk for mortality compared with matched controls, although evidence of an association is less strong among those with psoriatic arthritis (PsA), according to the results of a retrospective population-based cohort study conducted in Denmark and published in the British Journal of Dermatology.
The investigators sought to explore the risk for and leading causes of mortality among patients with psoriasis and PsA. Persons with a hospital-based diagnosis of either disorder were identified through the Danish National Patient Registry. Matched controls were identified from the general population of Denmark. Main outcome measures of the study were risk for death and cause-specific mortality among patients with psoriasis and PsA.
Mortality rates per 1000 patient-years were as follows: 22.29 (95% CI, 19.71-24.87) in those with psoriasis vs 13.89 (95% CI, 11.75-16.03) among controls and 10.83 (95% CI, 8.90-12.76) in those with PsA vs 11.63 (95% CI, 9.64-13.62) among controls. Survival, based on the use of stratified hazard ratios (HRs), was significantly lower in patients with psoriasis compared with controls (HR 1.74; P <.001) but did not differ significantly among those with PsA vs controls (HR 1.06; P =.190).
The significantly increased risk for death observed among those with psoriasis was associated with a number of causes, including diseases of the digestive system; endocrine, nutritional, and metabolic diseases; and certain infectious and parasitic diseases (HR 3.61, 3.02, and 2.71, respectively). In contrast, in patients with PsA, increased risk for mortality was observed only for certain infectious and parasitic diseases (HR 2.80) and for diseases of the respiratory system (HR 1.46).
Overall, patients with psoriasis died at a significantly younger age than did controls (mean age at death, 70.96 years vs 74.51 years, respectively; P <.0001).
The investigators concluded that patients with a hospital-based diagnosis of psoriasis have an elevated risk for death compared with matched controls, mainly caused by neoplasms and diseases of the digestive, circulatory, and respiratory systems. This increased burden of comorbidity may have implications for the increased mortality risk reported among those with psoriasis.
Skov L, Thomsen SF, Kristensen LE, Dodge R, Hedegaard MS, Kjellberg J. Cause-specific mortality in patients with psoriasis and psoriatic arthritis [published online June 27, 2018]. Br J Dermatol. doi: 10.1111/bjd.16919