Written by Jessica Patella, ND. This study showed that those with high blood levels of vitamin D were 5.15 times less likely to have rheumatoid arthritis.
Autoimmune rheumatic disorders are a group of chronic autoimmune conditions related to significant illness and death (1). Rheumatoid arthritis is the most common disease in this group. Within 10 years, over 50% of people with rheumatoid arthritis become disabled if they are not treated properly (1, 4). The high prevalence of vitamin D deficiency in northern North America, due to long winters and the high prevalence of rheumatoid arthritis, raises a concern about the correlation between the two (1).
Recent research included 116 participants, 60 participants with an autoimmune rheumatic disease (average age 54.5 +/- 13 years) and 56 participants in the control group without autoimmune conditions (average age 65.0 +/- 11.7 years) from Canada. In the autoimmune disease group, the most common disease was rheumatoid arthritis. In the control group, most participants were diagnosed with osteoarthritis and osteoporosis (1). Osteoarthritis is due to wear and tear, where the cartilage in the joint breaks down over time. Rheumatoid arthritis is different, in that it is an autoimmune disease, where the body attacks itself, causing inflammation in the joints, which eventually erodes the joint itself (6).
Vitamin D blood levels were measured in all participants and results were significantly lower in the rheumatoid group (64.8 +/- 29.8 vs. 86.8 +/- 37.7 nmol/L; p<0.05). In the control group, 19.6% of participants were vitamin D deficient, while 34.5% of rheumatoid participants were vitamin D deficient (deficient = plasma 25(OH)D < 50 nmol/L) (1). Interestingly, 83.9% of the control group and 91.7% of the rheumatoid group reported supplementing 1000 IU vitamin D per day (1). This indicates that 1000 IU per day may not be adequate enough to keep vitamin D levels at optimal levels (optimal = greater than or equal to 75 nmol/L) (1).
A disease activity score (DAS 28-ESR) was used to measure disease activity of rheumatoid arthritis. The score is calculated based on the number of tender and swollen joints out of 28 specified joints and the erythrocyte sedimentation rate (ESR), which measures the amount of inflammation in the body (1). A score greater than 5.1 is considered high, a score below 3.2 is considered low and a score of less than 2.6 indicates the disease is in remission (2).
A total of 59.7% of the rheumatoid group had disease activity scores above 2.6 (the cutoff for remission). There was also a significant negative correlation between vitamin D levels and disease activity (r=-.043, p=0.01), which means there was higher disease activity with lower blood levels of vitamin D (1). Overall, the odds of having active rheumatoid disease was 5.15 times higher in participants with low vitamin D levels, compared to those with adequate levels (OR=5.15, 95%CI 1.16, 22.9; p=0.031) (1).
In conclusion, there is a correlation between low levels of vitamin D in the blood and higher rates of autoimmune rheumatoid disease. For this reason, vitamin D levels should be monitored more closely in people with rheumatoid arthritis and autoimmune rheumatoid disease. Researchers also suggested vitamin D supplementation of 1500-2000IU for healthy adults based on this research and previous research (1, 3). Future research with more participants and to determine the ideal supplement amount should still be conducted.
Source: Sabbagh, Zohreh, Janet Markland, and Hassanali Vatanparast. “Vitamin D status is associated with disease activity among rheumatology outpatients.” Nutrients 5.7 (2013): 2268-2275.
© 2013 by the authors; licensee MDPI, Basel, Switzerland Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/).
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Posted August14, 2013.
Jessica Patella, ND, is a naturopathic physician specializing in nutrition and homeopathic medicine and offers a holistic approach to health. She earned her ND from Southwest College of Naturopathic Medicine in Tempe, AZ, and is a member of the North Carolina Association of Naturopathic Physicians. Visit her website at www.awarenesswellness.com.
References:
- Sabbagh Z, et al. Vitamin D Status is Associated with Disease Activity among Rheumatology Outpatients. Nutrients 2013, 5, 2268-2275; doi:10.339/nu5072268
- The DAS28 Score. National Rheumatoid Arthritis Society.
- Holick, M.F. Evidence-based D-bate on health benefits of vitamin D revisited. Dermatoendocrinology 2012, 4, 183–190.
- The Impact of Arthritis in Canada: Today and over the Next 30 Years. Arthritis Network Canada.
- Arthritis. Rheumatoid Arthritis. Centers for Disease Control and Prevention.
- Arthritis. Osteoarthritis vs. Rheumatoid arthritis. Mayo Clinic.
