The more the surface area of the body is covered by psoriasis, the greater the risk of death for the patient suffering from the condition, according to a study published in the Journal of Investigative Dermatology.
The study is the first to link psoriasis severity to an increased risk of death using Body Surface Area (BSA) rather than treatment patterns, such as whether or not a patient was receiving oral, injectable or phototherapy treatment for the condition.
The study found that patients with psoriasis on >10% of their body are at almost double the risk of death.
"It's well established that psoriasis is associated with an increased risk for other comorbidities like chronic kidney disease, diabetes, and cardiovascular disease, but we don't yet understand how the severity of psoriasis impacts future risk of major health problems," said senior author Joel M. Gelfand, MD, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.
Using a database from the United Kingdom, the researchers looked at 8,760 patients with psoriasis and 87,600 people without it. They sent surveys to the patient's general practitioners to determine the BSA affected by psoriasis because this information is not routinely available in medical records. They then looked at the number of deaths in each group by person-years.
The researchers used an average follow-up time of about 4 years. In that time, there was an average of 6.39 deaths per 1,000 person years in patients with psoriasis on >10% of their bodies, compared with 3.24 deaths in patients without psoriasis.
Even when researchers adjusted for other demographic factors, patients with a BSA >10% were 1.79 times more likely to have died -- almost double than other people their age and gender who do not have the condition. This risk persisted even when controlling for other risk factors like smoking, obesity, and other major medical conditions.
"Other studies that have examined this question, including our own prior research, have looked at patients who were receiving treatment for psoriasis, which is not an objective measurement of severity, making it unclear to whom the prior studies apply," said lead author Megan H. Noe, MD, University of Pennsylvania. "By using BSA, which we can evaluate in a patient's clinical visit, we can better understand which patients are at highest risk for future medical problems and need preventative care."
The researchers said more research is needed to better understand the specific causes of death in patients with extensive psoriasis and to see if and how treatment can impact the risk.
SOURCE: Penn Medicine