Researchers have found that each 1-unit increase in blood total mercury levels may be associated with an increase in the risk of developing psoriasis among U.S. adults, according to a recent study.

In the study, published in PLOS ONE, investigators examined the association between blood total mercury levels and psoriasis in U.S. adults, utilizing data from the 2005 to 2006 and 2013 to 2014 National Health and Nutrition Examination Survey. The analysis included 6,086 participants, with 150 (2.46%) of them self-reporting a diagnosis of psoriasis.

The results indicated a statistically significant positive correlation between blood mercury concentrations and the prevalence of psoriasis. Specifically, each 1-unit increase in blood total mercury was associated with an 8% increase in the risk of developing psoriasis (odds ratio [OR] = 1.08, 95% confidence interval [CI] = 1.03–1.14). Additionally, the participants in the highest quartile of blood mercury exposure had a 45% increased risk of psoriasis compared with those in the lowest quartile (OR = 1.45, 95% CI = 1.10–2.38).

Subgroup analyses revealed a stronger association in nondiabetic adults, with a 5% increase in psoriasis risk per 1-unit increase in blood mercury levels (P for interaction < .05).

The investigators identified a positive relationship between total blood mercury levels and the prevalence of psoriasis among adults in the United States. 

Full disclosures can be found in the published study.