Occipital Nerve Stimulation for Chronic Migraine: Long-Term Outcomes

Over 40% of patients with intractable chronic migraine who received occipital nerve stimulation treatment experienced long-term clinical benefit, according to a study published in The Journal of Headache and Pain.¹

The study team, led by Dr Sarah Miller of the Institute of Neurology and The National Hospital for Neurology and Neurosurgery in London, examined outcomes for a cohort of 53 patients from a single treatment center after a median follow-up of 42 months. All patients received occipital nerve stimulation implants consisting of bilateral ONS electrodes, leads and an implantable pulse generator between 2007 and 2013.Chronic migraine is defined as more than 15 headache days per month over a 3 month period. While many patients with chronic migraine benefit from medical treatment, 5% either cannot tolerate or prove refractory to evidence-based therapies.

In an interview, Dr Matthew S Robbins of Montefiore Medical Center and the Albert Einstein College of Medicine told Clinical Pain Advisor that chronic migraine is difficult to treat.

“Current options consist of therapies all borrowed from other disciplines and are not “designer drugs” for migraine therapy. All such treatments have a latency period to see an effect, and many are difficult to tolerate,” he stated.

The primary outcome measure for the Miller study was a 30% or greater decline in mean monthly moderate-to-severe headache days, defined as days in which pain was more than 4 on the verbal rating score and lasted at least 4 hours. This measure was met by 45.3 % (n=24) of patients. Monthly moderate-to-severe headache days fell by 37.1% across the whole cohort, a fall of 8.51 days (95% CI 5.63, 11.38; P <.001).

In 37.7% of patients (n=20), monthly moderate-to-severe headache days fell by 50 % or more. Significant reductions also occurred in measures of pain intensity, daily pain duration and headache-related disability. The complication rate was lower than previously reported, with no incidents of lead migration and only one minor infection.

Dr Robbins noted that, while neurostimulation devices have reached “primetime” for migraine therapy, their use is associated with a number of drawbacks, including high costs and the potential for procedurally related complications such as lead migration and infection. 

“Many headache specialists have moved away from referring patients with intractable chronic migraine for occipital nerve stimulation because it is an invasive procedure and the evidence from the 3 randomized controlled trials has not been terribly impressive,” he noted. 

“I think with the movement towards non-invasive neurostimulation devices, which are less in total costs, safer, and potentially just as effective, the role of occipital nerve stimulation may be uncertain. As the authors of the current study suggest, studies with a more modest primary end point of a 30% reduction in moderate-to-severe headache days are reasonable, but need to show a demonstrable improvement in quality of life for those with intractable chronic migraine – who are so desperate to get better and have some quality of life restored.”

Summary and Clinical Applicability

“Occipital nerve stimulation may be a safe and efficacious treatment for highly intractable chronic migraine patients even after relatively prolonged follow-up of a median of over 3 years,” the study team concluded.

According to Dr Robbins, the findings of the Miller study verify other work investigating long term use of occipital nerve stimulation for intractable chronic migraine.

“The results are generally positive with modest improvements, which is not a surprise given that there was no control group. However, the 2 previous randomized controlled trials of occipital nerve stimulation designed to assess efficacy showed no benefit over sham stimulation, so we generally do not know if this is an appropriate therapy given its invasiveness.”

Limitations and Disclosures

The authors disclosed the following competing interests: Sarah Miller has received educational and travel grants from St Jude Medical and Medtronic; Laurence Watkins has served on advisory boards for St Jude Medical and Medtronic; Manjit Matharu serves on the advisory board for Allergan, St Jude Medical and Medtronic and has received payment for the development of educational presentations from Allergan, St Jude Medical, Medtronic and electroCore.

Reference

1. Miller S, Watkins L, Matharu M. Long-term outcomes of occipital nerve stimulation for chronic migraine: a cohort of 53 patients. J Headache Pain. 2016;17(1).