Lifestyle Drives Much of Increased Cancer Risk in Psoriasis Patients

By Anne Harding

October 28, 2019

NEW YORK (Reuters Health) - People with psoriasis are more prone to develop and die from several site-specific cancers, but much of their greater risk is related to lifestyle factors such as smoking, alcohol use and obesity, according to a new systematic review and meta-analysis.

"There are multiple messages for those responsible for the care of people with psoriasis from these findings. At the most basic level, the results of this study may provide clinicians with the information required to spot early signs of associated site-specific cancers," said first author Alex M. Trafford of the University of Manchester, in the U.K.

"Another important message arises from the lower cancer risk seen in studies that took lifestyle factors into account," he told Reuters Health by email.

There is evidence for an increased risk of certain cancers in psoriasis patients, which is plausible due to the importance of inflammation in both conditions, Trafford and his colleagues note in JAMA Dermatology, online October 22.

Psoriasis therapies could increase cancer risk, they add, and people with psoriasis also have an increased prevalence of several cancer risk factors such as excessive alcohol use and obesity.

The authors reviewed 58 studies and found both severe psoriasis (relative risk, 1.22; nine studies) and psoriasis of any severity (RR, 1.18; seven studies) were significantly associated with an increased risk of cancer overall.

Risk of several site-specific cancers was also significantly increased, including colorectal (RR, 1.34), kidney (RR, 1.58), laryngeal (RR, 1.79), liver (RR, 1.83), esophageal (RR, 2.05), and pancreatic (RR, 1.41).

In four studies that looked at mortality and psoriasis severity, severe psoriasis was associated with significantly greater overall cancer mortality, as well as increased mortality risks for liver, esophageal and pancreatic cancer.

Subgroup analyses found "marked attenuation" of cancer incidence and mortality when studies controlled for smoking, alcohol consumption and obesity.

"Previous studies have already found that lifestyle changes, such as achieving a healthy weight and exercising, can reduce the severity of psoriasis," Trafford said. "As these results begin to suggest that healthy lifestyle changes may also reduce cancer risk, they reinforce the importance of targeting a holistic approach to psoriasis in care guidelines that incorporates lifestyle-behaviour change."


JAMA Dermatol 2019.