Psoriasis is More Than Skin Deep

Wednesday, August 14, 2019

Rebecca Bremner, MD

The dermatological medical community has known for a long time that psoriasis, a chronic, inflammatory condition of the skin, is extremely common and affects approximately 3 percent of the U.S. population. The classic presentation of psoriasis is thick, red, scaly plaques on the elbows and knees. Other common areas of involvement include the scalp, genitalia, palms and soles, buttocks and fingernails. Mild psoriasis is typically considered to be when the plaques involve less than 3 percent of the total body surface area (TBSA); moderate psoriasis 3-10 percent TBSA; and severe psoriasis >30 percent TBSA. Of course, percentage of skin involved is only one way to measure severity as people with only palm and sole involvement can be completely debilitated by the painful, cracking plaques in those relatively small areas. People of any age can be affected by psoriasis, although the average age of onset is the late twenties.

Psoriasis is not merely a skin disease but rather a multi-system inflammatory disease with negative implications for individuals’ overall health.

What has not been well known until recent years is that psoriasis is not merely a skin disease but rather a multi-system inflammatory disease with negative implications for individuals’ overall health. We have known for a long time that about a third of people with psoriasis will develop psoriatic arthritis. Less well known is that the same inflammation that is involved in psoriasis and psoriatic arthritis wreaks havoc throughout the body, and people with psoriasis have a higher risk of hypertension, high cholesterol, type 2 diabetes, cardiovascular disease, depression, inflammatory bowel disease and fatty liver disease.

Interestingly, there is also a direct correlation between the severity of psoriasis and the risk of heart attack and stroke. This begs the question of whether treatment of psoriasis, like treatment of hypertension or dyslipidemia, can lower this risk. In fact, recent data is emerging which suggests that systemic treatment of psoriasis with biologics not only improves skin disease but might actually lower the risk of cardiovascular events.

This knowledge fortunately coincides with the development of many new safe and effective treatments for psoriasis. Mild disease is still generally managed with topical treatments and ultraviolet therapy. For moderate to severe disease, there are many options including the older systemics such as methotrexate, cyclosporine and acitretin. The first generation of biologics were the TNF-inhibitors such as Humira, Enbrel and Remicade, which are helpful in treating psoriasis and psoriatic arthritis but are also used for many other TNF-mediated diseases such as inflammatory bowel disease and rheumatoid arthritis. The next generations of biologics have become narrower in targeting various psoriasis-specific interleukins. These medications include Stelara, Tremfya, Cosentyx and Taltz among several others, with many others in the development pipeline.

It is imperative that we encourage our patients with psoriasis to stop smoking, lose weight and drink only in moderation. However, we can also offer them systemic treatment which not only clears the rash but further decreases the risk of heart attack and stroke. Psoriasis is not just skin deep, and we finally have treatment options that get to the heart of the matter.