Psoriasis is widely regarded to be a chronic but non-fatal condition. However, a recently published study has found that severe psoriasis is associated with an elevated mortality rate. Severe psoriasis reduced life expectancy by 3.5 years for men and 4.4 years for women. “That’s significant. It’s 5% of the life span,” says the study’s lead author, Joel Gelfand, MD, an assistant professor of dermatology at the University of Pennsylvania School of Medicine in Philadelphia.
The size of the risk varied with age, but overall, people with severe psoriasis had a 50% higher death rate than those without psoriasis. The elevation in relative death rates was highest for younger patients and declined steadily with age, ranging from a 150% higher death rate at age 35 to a 10% higher death rate at age 95.1 Patients with mild psoriasis had the same rates of death as those without psoriasis.
It is not yet clear why patients with severe psoriasis face an increased risk of dying. The increased risk remained even after taking into account risk factors like obesity and heart disease. Dr. Gelfand’s group is currently analyzing data on the causes of death in psoriasis patients and hopes to report its findings soon.2
An important issue is the impact of psoriasis treatment on psoriasis-related mortality. So far it is unknown whether patients whose psoriasis is well controlled by treatment fare better than others. Although the patients with severe psoriasis in the current study were receiving systemic treatment, the authors collected no data on either the duration of or the effectiveness of that treatment. Methotrexate, for example, only works well for about half of the patients that try it, says Gelfand, and many patients have to stop taking it eventually because of toxic side effects. This study also does not address any potential influence of biologic therapies, as the records analyzed were from 1987-2002, the “pre-biologic era.”
Researchers are actively studying this troubling finding and will hopefully have some good answers for patients in the near future. In the meantime, Dr. Gelfand advises psoriasis patients to seek good medical care. “Patients need to get comprehensive health screens and make sure that problems get picked up and treated at an early stage. That’s the best we can offer right now,” he says.
The study is a reminder that psoriasis patients, perhaps even more than the general population, must work on those challenging health issues where we can have an impact. Each of these has health benefits of particular importance to those with psoriasis:
• Quitting smoking
• Reducing obesity
• Stopping alcohol abuse
• Addressing untreated depression
• Reducing high blood pressure
• Exercising
• Controlling cholesterol
• Complying with your psoriasis treatments
1. How the study was conducted: In the study, which was published in December 2007 in the Archives of Dermatology, Gelfand and his colleagues compared death rates over a 15-year period for people with severe psoriasis, mild psoriasis, or no psoriasis using a database of health information collected by primary care doctors in the United Kingdom. The database contains detailed medical records for more than 9 millions patients, male and female, of all ages, from all over the UK. Patients with psoriasis who had received systemic therapy–for example methotrexate, cyclosporine, or even UV light therapy–were classified as having severe psoriasis. Those who had psoriasis but no history of systemic treatment were classified as having mild psoriasis. The “no psoriasis” group consisted of patients without psoriasis randomly selected from the same medical practices that the psoriasis patients attended. In total, the authors analyzed records from approximately 4000 patients with severe psoriasis, 134,000 patients with mild psoriasis, and more than half a million patients without psoriasis.
2. Previous studies have shown that people with psoriasis are more likely than the general population to have risk factors for premature death, including obesity, cardiovascular disease, and certain types of cancer. However, Gelfand and his colleagues found that the presence of obesity, heart disease, cancer, and a number of other common diseases did not explain the higher death rate of patients with severe psoriasis. Despite this result, says Gelfand, the diseases they considered in their analysis might still be responsible for the excess deaths seen in psoriasis patients, perhaps because, for psoriasis patients, they are not completely identified in routine medical practice before they cause death. For example, a patient with no prior diagnosis of heart disease who dies of a heart attack might have had pre-existing coronary disease that had not come to medical attention. Alternatively, these diseases, once they develop, might be more deadly for psoriasis patients than for those without psoriasis.
