Study negates lifestyle factor link in psoriasis, cardiovascular fitness

A new study suggests that patients with psoriasis have poorer cardiorespiratory fitness and provides some intriguing insight: Lifestyle behaviors - such as being unwilling to exercise due to unsightly skin - may not be the culprit.

Study author Patrick Wilson, Ph.D., R.D., an assistant professor of Human Movement Sciences at Old Dominion University in Norfolk, Va., launched the study to better understand the connection between psoriasis and cardiorespiratory health.

RELATED: Meta-analyses clarify psoriasis comorbidities

“There's pretty good evidence to suggest individuals with moderate-to-severe psoriasis are at greater risk for cardiovascular and metabolic diseases like type 2 diabetes compared to otherwise healthy individuals,” he says. “One big remaining question is whether this increased risk is directly related to the disease process itself, lifestyle factors, drug therapies or a combination thereof.”

There’s little known in general about how people with psoriasis react to exercise, he says. “There is reason to believe that they may not tolerate certain types of exercise, and that they have substantial psychosocial barriers to participating in activities that expose their skin.”

For the new study, published Jan. 22 in the Journal of Physical Activity & Health, Dr. Wilson examined statistics about cardiorespiratory fitness (via a treadmill test), psoriasis prevalence and psoriasis severity from the 2003-2004 National Health and Nutritional Examination Survey.

Of 1,093 participants aged 20-59, 26 reported having had psoriasis in their lives. Those reporting psoriasis had lower levels of cardiorespiratory fitness (36.2 vs. 39.1 mL·kg-1·min-1, ρ = .009) than the other subjects.

The difference is statistically significant, the study says, although it’s not clear whether the difference matters on a clinical level. Still, research has suggested that the difference is near a level of improvement that’s been linked to reductions in rates of all-cause mortality and cardiovascular events.

The subjects with psoriasis didn’t seem to be getting less exercise, at least to judge by self-report and accelerometer readings. Severity of psoriasis didn’t appear to affect fitness levels either. And those with psoriasis didn’t have higher BMI levels, unlike patients in the general population.

Dr. Wilson believes more research is needed to better understand the possible connection between psoriasis and poorer cardiorespiratory health.

For now, he says, the study findings come with messages for dermatologists: “Screening for cardiovascular risk is a good idea, especially for those with moderate-to-severe disease,” he says.

And, he adds, dermatologists should remember that severe psoriasis may indeed prevent patients from getting exercise. As a result, “referral to other health professionals such as psychologists and exercise physiologists could be part of the treatment plan.”