As I live with the comorbidity of multiple sclerosis and rheumatoid arthritis, I am very interested in learning more about comorbidities in general. The coupling of diabetes and rheumatoid arthritis is one for which there is not a large amount of literature. Normally I write at the MS and RA sites here at HealthCentral and when I was asked to present some of the information I have learned in researching this comorbidity, I was happy to share with the MyDiabetesCentral community.
What is the prevalence rate of an RA and Diabetes comorbidity?
After reading through a number of research studies and literature published by the Centers for Disease Control and Prevention (CDC), National Institutes of Health, American Diabetes Association, and the Arthritis Foundation, I came to the conclusion that there doesn’t seem to be a strong relationships between these two diseases but that they also do not seem to avoid each other.
Read: Is There a Link between Rheumatoid Arthritis and Diabetes? for more on this subject.
"About 53% of people with diabetes also have arthritis" says the Arthritis Foundation.
That seemed to be a HUGE statement. But in looking at how this data was derived, it made much more sense. In 2008, the CDC released an analysis of data collected during phone surveys conducted in 2005 and 2007 as part of the Behavioral Risk Factor Surveillance System (BRFSS). Of nearly 800,000 persons who self-reported living with doctor-diagnosed diabetes, 52% answered yes to the question - “Have you ever been told by a doctor or other health professional that you have some form of arthritis, rheumatoid arthritis, gout, lupus, or fibromyalgia?”
So at least half of the people living with diabetes also need to be concerned with developing arthritis or other rheumatic diseases, such as RA, lupus, or fibromyalgia. That each of these diseases benefit from regular exercise, despite physical difficulties, was the take-home message of the CDC report: Arthritis as a Potential Barrier to Physical Activity Among Adults with Diabetes — United States, 2005 and 2007.
Does Plaquenil, a medication commonly used to treat RA, lower the risk of developing diabetes?
The Journal of the American Medication Association (JAMA) published a study which looked at that very question. (See Hydroxychloroquine and Risk of Diabetes in Patients With Rheumatoid Arthritis) Antimalarial drugs, like hydroxychloroquine (Plaquenil) which is commonly used in autoimmune diseases such rheumatoid arthritis and lupus, have been reported to cause both symptomatic and asymptomatic hypoglycemia and have been explored as an adjunct to insulin and oral hypoglycemic agents for poorly controlled type 2 diabetes.
Results from this 20+ year study showed a reduction in diabetes risk of up to 77% for RA patients taking hydroxychloroquine for more than 4 years, a finding that is comparable or superior to that of other drugs studied in clinical trials: rosiglitazone, combination hormone therapy, estrogen only, metformin, acarbose, and ramipril. Secondly, those who had taken hydroxychloroquine compared with those who had never taken the drug who had prevalent diabetes at enrollment or developed diabetes during the follow-up observation period were less likely to report use of hypoglycemic medication. Antimalarial drugs may have a role in treating rheumatoid arthritis not only to suppress inflammation of the joint-linings but also to reduce the likelihood of developing glucose intolerance and dyslipidemia.
A similar study confirms this connection, but with a 53% reduction rate in diabetes risk. (See Old Malaria Drug Reduces Diabetes Risk in RA, Protects Kidneys in Lupus)
Are there any complications of the RA and Diabetes comorbidity?
Recently a report was released which detailed the complications one diabetes patient had with the treatment used for her rheumatoid arthritis. (See Unstable diabetes in a patient receiving anti-TNF-aï¿¼ for rheumatoid arthritis) Expert below:
"Our case is a 55-yr-old female who has had type 1 diabetes since the age of 30. Aged 33, she developed rheumatoid arthritis. Having failed a number of disease-modifying anti-rheumatic drugs (DMARDs), she was commenced on etanercept (25 mg twice weekly) in April 2003 (Disease Activity Score = 7.06). This led to significant improvement in her joints immediately. Having previously had stable diabetes, within 3 weeks of commencing the drug, she noticed that her blood sugars were erratic. She had a severe hypoglycaemic attack without warning, followed further by one more a few days later. After urgent clinical review, the etanercept was stopped and her glycaemic control stabilized.
Despite commencing subcutaneous methotrexate, her joints remained markedly active, which ultimately led to her admission in October 2004. Her Disease Activity Score (DAS) score was 6.8, and after much consideration the patient was commenced on adalimumab. Within 12 h of administration, she developed severe hypoglycaemia, which recurred again 24 h later. The adalimumab was subsequently stopped.
The patient has continued with severe active joint disease. She has had severe side effects with a number of DMARDs and lack of efficacy with others. She has currently just had her third infusion of infliximab, as yet without complication."
Tumor necrosis factor-alpha (TNF-ï¿¼a) is involved in inflammation, is produced by abdominal fat, and has an effect on glucose homeostasis. It is known that weight loss is associated with reduced levels of TNF-aï¿¼ and improved insulin sensitivity in patients with and without type 2 diabetes. Also, anti-TNF drugs such as infliximab have been shown to improve insulin sensitivity. (See Anti-tumor necrosis factor-alpha blockade improves insulin resistance in patients with rheumatoid arthritis)
The important take-home message is that patients living with diabetes, who also have RA and use anti-TNF drug, should be warned regarding the possible disturbance of glycaemic control.