Individuals with immune-mediated diseases, such as psoriasis, are at higher risk for having other immune-mediated diseases. Here’s how psoriasis can lead to other conditions, and the associated costs.
Psoriasis patients can expect to spend as much as $25,796 per year on costs related to the autoimmune disease, according to a study in JAMA Dermatology. That amounts to $135 billion annually for the 7.4 million U.S. adults who have psoriasis.
The study also estimated that medical comorbidities cost $36.4 billion annually.
Individuals with immune-mediated diseases, such as psoriasis, are at higher risk for having other immune-mediated diseases, says Eric Ruderman, MD, associate chief of clinical affairs in the Division of Rheumatology at Northwestern Medical Group in Chicago. They also have a higher likelihood of having metabolic syndrome.
Here’s a look at how having psoriasis can lead to other conditions.
Psoriatic arthritis: Psoriatic arthritis affects about 30% of psoriasis patients, typically within the first eight years of having the disease. The same chemicals and immune response that produce psoriasis in the skin circulate in the blood and can trigger inflammation in the joints, says Matt Lewis, MD, MPH, a dermatologist at Stanford Health Care in Palo Alto, California. Psoriatic arthritis may lead to permanent joint damage and destruction. By contrast, skin doesn’t permanently scar from psoriasis.
Cardiovascular disease: Psoriasis is a risk factor for heart attack, even if other risk factors for heart disease are under control such as diabetes, smoking, obesity, and high blood pressure. Chronic inflammation in the blood is thought to play a key role, Lewis says.
Psychological disorders: While embarrassment due to the thick, raised scaly skin that psoriasis causes may lead to feelings of depression and anxiety, this is probably only part of the reason why psoriasis patients have an increased risk of developing these disorders. Lewis says. It’s probable that the chronic levels of inflammation in the blood directly result in depression. “We see similar phenomena in patients after strokes or major surgery,” he says.
Obesity: A reciprocal relationship most likely exists between obesity and psoriasis. That is, obesity is a risk factor for developing psoriasis and psoriasis may contribute to developing obesity. Psychosocial factors, including isolation and depression, only partially explain how psoriasis may lead to obesity, Lewis says. Furthermore, fat tissue releases inflammatory chemicals similar to those produced by psoriasis, which could be part of the biologic role of fat tissue increasing psoriasis risk. Similarly, weight loss-whether by exercise or gastric bypass-seems to improve psoriasis.
Diabetes: Obesity may play a role in psoriasis patients having an increased risk for developing diabetes. Also, the chronic inflammatory state of psoriasis may produce insulin resistance and increase the likelihood of developing diabetes, Lewis says.
Cancer: Individuals with psoriasis may have a slightly greater risk of getting certain cancers-most notably lymphoma. However, the true relationship between cancer and psoriasis is still being clarified. The risk may partially be due to some psoriasis therapies, which block an immune system chemical called TNF, Lewis says. This chemical may have a role in preventing some cancers. So blocking this chemical may slightly increase the risk for some cancers. The chronic inflammatory state of psoriasis may also play a role in increased cancer risk.
Ruderman says there is also concern for an increased risk of skin cancer in psoriasis patients who receive light therapy, and particularly those who have received light therapy with a photosensitizing medication.