Formed in the skin from cholesterol reacting with sunlight, vitamin D is not an essential nutrient. However, due to low light levels in some climates and more time spent at indoor activities, deficiencies are not uncommon. Beyond bone formation, vitamin D plays a variety of important roles in maintaining health, including reducing inflammation. Vitamin D deficiency can cause or complicate inflammatory conditions such as psoriatic arthritis. Consult with your doctor before supplementing with vitamin D.
High Correlation
A study published in the December 2009 "Rheumatology International" journal found a high correlation between vitamin D deficiency and inflammatory joint disease in Jews and Arabs living in Israel. Patients with rheumatoid arthritis, psoriatic arthritis or ankylosing spondylitis were included in the study. Vitamin D status was low in 42 percent of the participants, with a 76 percent incidence among Arabs and a 23 percent incidence among Jews. The researchers noted the surprisingly high incidence of vitamin D deficiency in patients with inflammatory joint disease, considering the high annual levels of sunshine the country receives, and called for more research to locate potential genetic variations in vitamin D receptors in these groups of people.
Intestinal Inflammation
Low bone density and intestinal inflammation occur in many psoriatic arthritis and ankylosing spondlylitis patients, according to a study published in the November 2010 "Rheumatology International" journal. In the study, scientists found a high prevalence of an immune marker associated with intestinal inflammation that can lead to decreased vitamin absorption in patients with ankylosing spondylitis but not for patients with psoriatic arthritis. The researchers note that as many as one-third of patients with these conditions experience low bone mass. In the study, reduced bone mass was observed in 57 percent of psoriatic arthritis patients.
Faulty Vitamin D Receptor
A genetic fault in vitamin D receptor function may be a factor in the development of psoriasis in some people, according to a study published in the December 2007 "Archives of Dermatology Research" journal. Vitamin D is used as a treatment for psoriasis and in some patients, vitamin D therapy is ineffective, say the researchers. In this study, the gene for the defective vitamin D receptor occurred in 91 percent of the psoriasis patients and 59 percent of the control group of people without psoriasis. The researchers conclude that the faulty gene may explain the lack of response to vitamin D therapy in some psoriasis patients.
Vitamin D-3 Therapy
Vitamin D-3 alleviated symptoms in psoriatic arthritis patients in a study published in the 2009 "Acta Dermato-Venereologica" journal. In the study, patients took 0.25 mcg of vitamin D-3 twice per day for six months. A statistically significant decrease occurred in the percentage of white blood cells and the blood levels of certain inflammatory immune molecules within the first three months and there was a continued decrease in activity of the disease throughout the six-month follow-up period.
References
- "Rheumatology International"; Vitamin D level: is it related to disease activity in inflammatory joint disease? Braun-Moscovici Y, et al.; 2009
- "Rheumatology International"; Antibodies to human tissue transglutaminase and alterations of vitamin D metabolism in ankylosing spondylitis and psoriatic arthritis. Teichmann J, etal.; 2010
- "Archives of Dermatologic Research"; Polymorphisms of vitamin D receptor gene in Turkish familial psoriasis patients. Dayangac-Erden D, etal.; 2007
- "Acta Dermato-Venereologica"; Immunological and clinical effects of alphacalcidol in patients with psoriatic arthropathy: results of an open, follow-up pilot study. Gaál J, et al.; 2009
