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Climate, Pollution, and Pemphigus Associated

Clin Exp Dermatol; ePub 2018 Jun 1; Ren, et al

Increasing temperature, UV exposure, and small particle air pollution are associated with increased hospitalization for pemphigus, according to a recent study. Therefore, patients with pemphigus may benefit from avoidance of these potential environmental triggers. The analysis used data from the 2002-2012 National Inpatient Sample, including 68,476,920 children and adults, and measurements of relative humidity (%), UV index, outdoor air temperature, and particulate matter of ≤ 2.5 or ≤ 10 μm (PM2.5 and PM10). Researchers found:

  • Higher rates of admission primarily for pemphigus occurred during the summer and autumn months (June-November), with the highest admission rates in July and October (both 19.7 per million).
  • There was significant statewide variation of the prevalence of hospitalization for pemphigus, with apparent hotspots located in the southwest and northeast states.
  • Hospitalization for a primary diagnosis of pemphigus vs other diagnosis was associated with significantly lower humidity, analysis of variance, and higher temperature, UV index, PM2.5, and PM10.
  • All associations remained significant in multilevel regression models that controlled for age, sex and race/ethnicity, except for ultraviolet index, which was associated with pemphigus hospitalization only for Hispanic patients.


Ren Z, Hsu D, Brieva J, Silverberg JI. Association between climate, pollution and hospitalization for pemphigus in the USA. [Published online ahead of print June 1, 2018]. Clin Exp Dermatol. doi:10.1111/ced.13650.