Common muscle relaxants associated with increased COPD exacerbation risk

Key takeaways:

• Patients using cyclobenzaprine or methocarbamol had increased relative risk for COPD exacerbations, researchers found.
• Physicians should use caution when prescribing these medications to patients with COPD.

BOSTON — Patients with COPD using the common muscle relaxants cyclobenzaprine or methocarbamol had increased risk for COPD exacerbations at follow-up, according to data presented at the CHEST Annual Meeting.

Irakli Lemonjava

“In our analysis, patients on these medications demonstrated a consistently higher risk — 2% more — of COPD exacerbations at both the 3-year and 5-year follow-up intervals when compared to the control group,” Irakli Lemonjava, MD, of the department of medicine at Jefferson Einstein Hospital, told Healio.

Because previous research has shown an association between use of gabapentinoids and COPD exacerbations, Lemonjava and colleagues investigated whether such an association existed with commonly prescribed muscle relaxants, cyclobenzaprine and methocarbamol.

Researchers used the TriNetX platform to identify the cohorts, which included patients aged older than 18 years who were diagnosed with COPD from 2000 on, who researchers then used propensity score matching to stratify into two groups: the muscle relaxant group (n = 399,886) and the control group with no muscle relaxant use (n = 429,743).

Researchers followed patients to identify COPD exacerbations at 1, 3 and 5 years.

Results showed that at 1-year follow-up, 21,922 (5.482%) patients in the muscle relaxant group experienced a COPD exacerbation vs. 21,513 (5.006%) patients in the control group. These data equated to a 9.5% relative risk (RR = 1.095; 95% CI, 1.075-1.115) increase for developing a COPD exacerbation with muscle relaxant use.

This risk rate increased to 17.6% at year-3 follow-up (10.182% vs. 8.656%; RR = 1.176; 95% CI, 1.161-1.192) and 20.2% at year-5 follow-up (12.385% vs. 10.303%; RR = 1.202; 95% CI, 1.188-1.217).

“Physicians may need to practice with greater caution when prescribing this class of medications, particularly in patients with a known diagnosis of COPD, to mitigate the potential for exacerbations,” Lemonjava told Healio.

Future clinical trials should be performed to validate these results, he added.

For more information:

Irakli Lemonjava, MD, can be reached at irakli.lemonjava@jefferson.edu.