Although the symptoms and risk factors for migraine and multiple sclerosis (MS) often overlap, it is not known whether these two conditions are independent or share a common biological etiology, such as genetics. Results of a study have now uncovered several genetic variants.
Up to 69% of MS patients also suffer from migraine. In the process, the affected persons indicate their pain with 6 points on the visual analog scale. 15% of them suffer from headaches on at least 15 days per month, but usually an episodic course occurs. Whether migraine and MS have common bases was previously unknown. Therefore, in a recent study, data from 1094 MS patients and 12 176 control participants were analyzed to determine whether genetic variants independently associated with migraine or MS could be identified. Migraine status was determined using self-report and a validated electronic health record algorithm.
The search for variables
Previous genome-wide association studies of MS or migraine have been used to identify variants. After quality control, the researchers analyzed 902 variants with minor allele frequencies greater than 1%. Observed and permuted P for each phenotype was obtained by logistic regression and compared with the identified variants associated with both phenotypes. Logistic regression models were adjusted for sex and ancestry among all variants significantly associated with both phenotypes. The migraine model was adjusted for a propensity score representing the probability of MS case-control status to account for a possible bias in identifying a secondary phenotype from a case-control study.
Common genetics
Among the 1094 patients with MS, the mean age was 49.95 years compared with 49.01 years in controls. The mean MS severity score was 3.21. Migraine incidence was significantly higher in MS patients (40%) than in controls (29%). Preliminary results found five genetic variants (rs6677309, rs10801908, rs1335532, rs62420820, and rs17066096) significantly associated with both MS and migraine. Three of these were protective for MS (rs6677309, rs10801908, and rs1335532), but all variants increased the likelihood of migraine.
MS and Mirgäne share several variants
The study researchers concluded that the prevalence of migraine was significantly higher in people with MS compared with healthy controls. Several genetic variants are shared between both entities. Implicated genes include CD58-which modulates regulatory T cells-and several immune genes (IL20RA, IL22RA2, IFNGR1, and TNFAIP3) within the 6q23 chromosomal region. Because several variants increase the risk of migraine but decrease the risk of MS, this may have implications for targeted therapies and treatments.
Source: ACTRIMS Forum 2020
Further reading:
- Horton M, Robinson S, Shao X, et al: Discovery of shared genetic variants associated with multiple sclerosis and migraine. Presented at: 5th Annual Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) Forum; February 27-29, 2020; West Palm Beach, FL. Abstract P140.
InFo NEUROLOGY & PSYCHIATRY 2020; 18(2): 34 (published 3/25/20, ahead of print).
