SAN DIEGO — The treatment has long been used in adults, and frequently in children on the strength of observational evidence.
Prior Research
Most of the studies have been conducted in adults, and these were often in specific settings like the emergency department for status migrainosus, while outpatient studies were generally conducted in chronic migraine, according to presenting author Christina Szperka, MD. “The assumptions were a little bit different,” Dr. Szperka, director of the pediatric headache program at Children’s Hospital of Philadelphia, said in an interview.
Dr. Christina Szperka
Retrospective studies are also fraught with bias. “We’ve tried to look at retrospective data. People don’t necessarily report how they’re doing unless they come back, and so you lose a huge portion of kids,” said Dr. Szperka, who presented the research at the annual meeting of the American Headache Society.
“From a clinical perspective, I think it gives us additional evidence that what we’re doing makes a difference, and I think that will help us in terms of insurance coverage, because that’s really been a major barrier,” said Dr. Szperka.
The study also opens other avenues for research. “Just doing the greater occipital nerves only reduces the pain so much. So what’s the next step? Do I study additional injections? Do I do a study where I compare different medications?”
She previously conducted a study of how providers were using lidocaine injections, and “there was a large amount of variability, both in terms of what nerves are being injected, what medications they were using, the patient population, et cetera,” said Dr. Szperka. Previous observational studies have suggested efficacy in pediatric populations for transition and prevention of migraine, new daily persistent headache, posttraumatic headache, and post-shunt occipital neuralgia.
A Randomized, Controlled Trial
In the new study, 58 adolescents aged 7 to 21 (mean age, 16.0 years; 44 female) were initially treated with lidocaine cream. The patients were “relatively refractory,” said Dr. Szperka, with 25 having received intravenous medications and 6 having been inpatients. After 30 minutes, if they still had pain and consented to further treatment, Dr. Szperka performed bilateral greater occipital nerve injections with lidocaine or a saline placebo, and did additional injections after 30 minutes if there wasn’t sufficient improvement.
There was no significant change in pain after the lidocaine cream treatment, and all patients proceeded to be randomized to lidocaine or placebo injections. The primary outcome of 30-minute reduction in pain score ranked 0-10 favored the lidocaine group (2.3 vs 1.1; P = .013). There was a 2-point reduction in pain scores in 69% of the lidocaine group and 34% of the saline group (P = .009) and a higher frequency of pain relief from moderate/severe to no pain or mild (52% versus 24%; P = .03). There was no significant difference in pain freedom.
After 24 hours, the treatment group was more likely to experience pain relief from moderate/severe to no pain or mild (24% vs 3%; P = .05) and to be free from associated symptoms (48% vs 21%; P = .027). Pain at the injection site was significantly higher in the placebo group (5.4 vs 3.2), prompting a change in plans for future trials. “I don’t think I would do saline again, because I think it hurt them, and I don’t want to cause them harm,” said Dr. Szperka.
Adverse events were common, with all but one patient in the study experiencing at least one. “I think this is a couple of things: One, kids don’t like needles in their head. Nerve blocks hurt. And so it was not surprising in some ways that we had a very high rate of adverse events. We also consented them, and that had a long wait period, and there’s a lot of anxiety in the room. However, most of the adverse events were mild,” said Dr. Szperka.