US Pharm. 2016;41(6):11.

The third most common disease category, after cancer and heart disease, is autoimmune disease (AD), affecting 5% to 8% of the U.S. population. Autoimmunity is the second highest underlying cause of >100 serious chronic illnesses, with >50 million Americans possessing at least one serious chronic illness. The National Institutes of Health’s (NIH) Office of Research on Women’s Health has declared autoimmune disease to be a major women’s health issue because it is one of the 10 leading causes of death in women aged <65 years. It is also the fourth largest cause of disability in women. At least 15 diseases result directly from an autoimmune response, and >80 conditions are associated with autoimmunity. Genetic background is responsible for AD in 30% of cases; inherited factors are the cause in 70% of cases.

Psoriasis: According to the NIH, 2.2% of the U.S. population (7.5 million) has psoriasis. Incidence depends on climate and genetic makeup. It is believed that 10% of people inherit one or more of the 25 genetic variants that could eventually lead to psoriasis. Because psoriasis is less common in tropical climates and in dark-skinned persons, it is thought that sunlight may improve psoriasis by decreasing T cells. Of those with psoriasis, 80% have mild-to-moderate disease and 20% have moderate-to-severe disease affecting >5% of the body surface area. Plaque psoriasis is the most common form of psoriasis, occurring in 80% to 90% of patients with psoriasis. In 2013, the total direct cost of treatment for psoriasis was between $51.7 billion and $63.2 billion. Psoriatic arthritis occurs in 30% to 50% of psoriasis patients.

Psoriasis Comorbidities: The incidence of Crohn’s disease and ulcerative colitis is 3.8 to 7.5 times higher in psoriasis patients than in the general population. Psoriasis patients also have increased incidences of lymphoma, heart disease, obesity, type 2 diabetes, and metabolic syndrome. The prevalence of depression is as high as 50%. Three of every 10 people with psoriasis will get psoriatic arthritis, and four of every 10 with psoriatic arthritis report swollen toes or fingers. In severe cases, joints may be permanently damaged.

Lupus: Lupus is a chronic, complex, and prevalent autoimmune disease affecting >1.5 million Americans. More than 90% of lupus patients are female, and most are aged 15 to 44 years when lupus develops; one in five people with lupus is aged <20 years. Minority women tend to develop lupus at a younger age, experience more serious complications, and have higher mortality rates. Lupus is a leading cause of kidney disease, stroke, and heart disease in women of childbearing age.

To comment on this article, contact rdavidson@uspharmacist.com.