More than 9 million ESIs each year
Each year, more than 9 million ESIs are administered to patients in the United States to relieve radicular back and leg pain that may be caused by a herniated disc or spinal stenosis (a gradual narrowing of the open spaces in the spinal column, which is common in older adults), the researchers explained.
Some patients experience sufficient pain relief with ESIs. Others may not be eligible for surgery and may receive multiple ESIs annually for many years because they provide pain relief.
It is well established that oral and intravenous glucocorticoids profoundly suppress bone formation and transiently increase bone resorption, causing substantial bone loss and increased fracture risk within 3 months of administration, Ms. Clare explained in the session.
Long-term use of high-dose inhaled glucocorticoids has been associated with bone loss and fractures. However, the effect of ESIs on bone has been less well studied.
The researchers hypothesized that ESIs are systemically absorbed and cause suppression of bone formation without a compensatory decrease in bone resorption.
They enrolled 24 patients who had undergone lumbar ESIs and 8 control patients. The mean age of the patients in the two groups was 63 years and 68 years, respectively. Most patients were White (88% and 100%, respectively). The mean body mass index was 27 kg/m2 and 28 kg/m2, respectively. On average, the patients had entered menopause 12 and 16 years earlier, respectively.
In the group that received steroid injections, almost two-thirds (15 patients, 63%) received triamcinolone. The rest received dexamethasone (six patients, 25%) or betamethasone (three patients, 12%) at doses that were equivalent to 80 mg triamcinolone.
The patients’ baseline serum levels of 25-hydroxy vitamin D, parathyroid hormone, cortisol, P1NP, osteocalcin, and CTX were within the reference ranges and were similar in the two groups.
The researchers also determined serum levels of cortisol (to assess suppression of endogenous glucocorticoids), osteocalcin, P1NP, and CTX in the patients and control persons at 1, 4, 12, 26, and 52 weeks after patients had received the ESI.
The researchers acknowledged that the small sample is a study limitation. In addition, the first serum samples were taken 1 week after the injection, and so any earlier changes in analyte levels were not captured. The patients also received different types of steroids, although the doses were similar when converted to triamcinolone equivalents.
The study was supported by a Spine Service grant from the Hospital for Special Surgery. The authors disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.