An old and inexpensive drug, hydroxychloroquine, has been found to help prevent type 2 diabetes in people with rheumatoid arthritis.
Hydroxychloroquine, which was first used fifty years ago to prevent and treat malaria, is currently used to reduce the pain, swelling, and disability of rheumatoid arthritis and other auto-immune diseases.
The study’s lead author, Dr. Mary Wasko of the University of Pittsburgh, became curious about hydroxychloroquine’s effect on type 2 diabetes when one of her patients developed low blood sugar while taking it. She was also surprised by the relatively low rates of type 2 diabetes among her arthritic patients, many of whom have multiple risk factors for diabetes.
So she examined a database of nearly 5,000 people with rheumatoid arthritis, of whom about 1,800 had taken hydroxychloroquine.
During the twenty-year period covered by the database, type 2 diabetes was developed by 54 people who had taken hydroxychloroquine and 171 who had not taken it. Overall, then, taking hydroxychloroquine reduced risk of diabetes by 38 percent.
Moreover, the longer patients took hydroxychloroquine, the lower their risk of diabetes: taking the drug longer than four years produced a 77 percent reduced risk of diabetes. And among the patients who did develop diabetes, those who had taken hydroxychloroquine were less likely to need blood sugar-lowering medications to control it.
The researchers note that hydroxychloroquine has also produced improvements in insulin resistance and glucose metabolism in people with lupus and in animals. Unfortunately, they have no idea how the drug does what it does. Before it can be used for prevention of type 2 diabetes, its mechanism of action will need to be understood.
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Sources: JAMA, July 2007; EurekAlert