Except for cataracts, side effects in PMR patients treated with glucocorticoids and non-PMR patients were not statistically different, new research finds.
By Kathleen Doheny
Interviews with Eric L. Matteson, MD, MPH, and Don L. Goldenberg, MD
Glucocorticoids, primarily prednisone, are the standard treatment for those affected by polymyalgia rheumatica (PMR), a common inflammatory disease of older adults that causes joint pain. Unfortunately, steroid use is known to be associated with adverse effects, including a risk of developing diabetes, osteoporosis, fractures, high blood sugar, cataracts, and other problems.
New research suggests most of those adverse effects are no more common in PMR patients treated with glucocorticoids than in matched control patients without PMR who aren't treated with the drugs.1
"The event rates for the side effects that we often attribute to steroids were actually the same in the control group, except for cataract development," said Eric L. Matteson, MD, MPH, a consultant and professor of medicine at Mayo Clinic Rochester and senior author of the study.
He believes this is the first study to compare side effects in PMR patients treated with steroids and patients without a PMR diagnosis and not on steroids. Besides the finding on side effects, he added, the research shed light on factors such as average doses and length of treatment.1
Study Details
The American College of Rheumatology and European League Against Rheumatism issued joint recommendations in 2015, recommending the lowest starting dose and least duration to manage the condition. It recommends a start dose of 12.5 to 25 mg of prednisone equivalent daily, not to surpass 30 mg.2
Dr. Matteson and his team, all from Mayo Clinic, used a population-based inception cohort, obtaining details of the glucocorticoid therapy from the medical records of 359 patients diagnosed with PMR from 2000 through 2014. Next, they found 359 age- and sex-matched controls without PMR from the same population.
They looked at cumulative and daily doses of steroids, rate of disease relapses, the rate of discontinuation and side effects.1
In the new study, the median time to taper below 5 mg a day for 6 months was 1.44 years (95% CI, 1.36-1.62) and the median time to permanent discontinuation was 5.95 years (95% CI: 3.37-8.88). At 2 years, the mean cumulative dose was 4 g and at 5 years, 6.3 g. The mean daily dose at 2 years was 6.1 mg and 7.2 mg at 5 years. The average initial dose was 16.9 mg daily.
The researchers found no statistically significant differences in the rates of diabetes, hypertension, hyperlipidemia, or fractures of the hip, vertebrae or Colles fractures between PMR patients and controls. (P > 0.2 for all). However, those on steroids were more likely to develop cataracts (hazard ratio 1.72; 95% CI: 1.23-2.41).
Among the noteworthy findings:
A significant proportion of those with the condition were on low-dose steroids for many years.
Those on lengthy treatment do experience a high rate of steroid-related complications, but except for cataracts, these comorbidities are no more common in PMR patients than in non-PMR patients.1
Expert Perspective
Historically, physicians have worried about using higher doses of steroids for longer periods of time, said Don Goldenberg, MD, professor of medicine, emeritus at Tufts University School of Medicine and adjunct faculty, department of medicine and nursing, Oregon Health Sciences University, Portland. He is a member of the Practical Pain Management editorial board and reviewed the new findings.
The findings are mostly reassuring, he said, although those on steroids did have a higher incidence of cataracts The cumulative incidence of cataracts at 5 years after the PMR diagnosis was 41% for those diagnosed compared to 27.3% of those not diagnosed. He, too, pointed to the possibility that those with PMR may have had more eye exams, which the authors of the study also noted.
The initial mean starting dose (16.9 mg daily) and the duration of steroid use was a bit surprising, he said. The average among rheumatologists is about 10 or 15 mg, he said, "I personally seldom had patients on for 6 years.''
Even so, he believed that ''the good news outweighs the bad news here."
More Insights from Dr. Matteson
While the association guidelines do spell out an ideal dose range, they do not specify ideal length of treatment, noted Dr. Matteson, instead specifying the minimum effective duration.
In general, Dr. Matteson told Practical Pain Management, ''it's been thought 2 or 3 years'' might be enough. However, the median in the study was actually 6 years. The study also suggested relapses are common and most often occur in the first 2 or 3 years, he said.
Although the overall event rates were not different, except for cataracts, Dr. Matteson said, some individuals did have troublesome side effects.
The study excluded some, including those who already had diabetes. So the study did not look at whether the steroids led to a worsening of pre-existing conditions, he said. The study also excluded those with giant cell arteritis (GCA), which can occur with PMR.
The higher incidence of cataracts in the steroid-treated group may have been due to concerns about coexistent GCA, and that might have triggered eye exams and the discovery of cataracts soon after the diagnosis, the authors noted in the article.
While the findings are somewhat good news regarding side effects, steroids are often not popular among patients, Dr. Matteson noted, due to other concerns, such as the weight gain associated with steroid use. The researchers did not examine weight gain. Nor did they look at appearance changes due to the drug or mood changes, also problematic for patients.
Dr. Matteson emphasized that these findings do not mean that experts should not continue to look for a better treatment options.
Polymyalgia rheumatica
Polymyalgia Rheumatica- PMR
