GianlucaSeveri, Associate Professor, University of Florence
TobiasKurth, Professor, Institute of Public Health Charité - Universitätsmedizin Berlin
Submitted May 30, 2021
We thank Dr. Gupta for the interest in our article. The comment raises questions of the validity of epidemiological studies or of meta-analyses in general, when investigating clinically relevant topics. We respectfully disagree, and advise that rather rigorous application of adequate methods is important. As with all observational studies, confounding should be considered carefully. However, epidemiological studies have been of considerable help since the 19th century for many conditions including understanding cardiovascular diseases.2 Although we cannot exclude that unmeasured confounding may explain the observed associations between migraine and incident hypertension, the replication of these results in other cohorts with a variety of backgrounds and settings makes this possibility unlikely. Associations between migraine and incident hypertension have been reported in prospective studies in the USA, Finland, and the Netherlands.3-5
In our study we found no evidence of a difference in the hazard ratios for hypertension between women with and without aura (MA+/MA-), which is consistent with Dr Gupta’s claim that there are no phenotypical differences. We do, however, believe that in this study MA+ may be less prone to misclassification than MA- migraine. Similarly, no significant difference in the hazard ratios was observed when considering treated versus untreated migraine. The main takeaway for clinicians is that post-menopausal women with a history of migraine appear more likely to be at risk of hypertension, even if the mechanisms behind this are currently unclear.
Disclosure
The authors report no relevant disclosures. Contact journal@neurology.org for full disclosures.
References
MacDonald CJ, El Fatouhi D, Madika AL, et al. Association of Migraine With Incident Hypertension After Menopause: A Longitudinal Cohort Study [published online ahead of print, 2021 Apr 21]. Neurology. 2021;10.1212/WNL.0000000000011986.
Yu E, Rimm E, Qi L, et al. Diet, Lifestyle, Biomarkers, Genetic Factors, and Risk of Cardiovascular Disease in the Nurses' Health Studies. Am J Public Health. 2016;106(9):1616-1623. doi:10.2105/AJPH.2016.303316
Scher AI, Terwindt GM, Picavet HS, Verschuren WM, Ferrari MD, Launer LJ. Cardiovascular risk factors and migraine: the GEM population-based study. Neurology. 2005;64(4):614-620. doi:10.1212/01.WNL.0000151857.43225.49
Rist PM, Winter AC, Buring JE, Sesso HD, Kurth T. Migraine and the risk of incident hypertension among women. Cephalalgia. 2018;38(12):1817-1824. doi:10.1177/0333102418756865
Entonen AH, Suominen SB, Korkeila K, et al. Migraine predicts hypertension--a cohort study of the Finnish working-age population. Eur J Public Health. 2014;24(2):244-248. doi:10.1093/eurpub/ckt141
We thank Dr. Gupta for the interest in our article. The comment raises questions of the validity of epidemiological studies or of meta-analyses in general, when investigating clinically relevant topics. We respectfully disagree, and advise that rather rigorous application of adequate methods is important. As with all observational studies, confounding should be considered carefully. However, epidemiological studies have been of considerable help since the 19th century for many conditions including understanding cardiovascular diseases.2 Although we cannot exclude that unmeasured confounding may explain the observed associations between migraine and incident hypertension, the replication of these results in other cohorts with a variety of backgrounds and settings makes this possibility unlikely. Associations between migraine and incident hypertension have been reported in prospective studies in the USA, Finland, and the Netherlands.3-5
In our study we found no evidence of a difference in the hazard ratios for hypertension between women with and without aura (MA+/MA-), which is consistent with Dr Gupta’s claim that there are no phenotypical differences. We do, however, believe that in this study MA+ may be less prone to misclassification than MA- migraine. Similarly, no significant difference in the hazard ratios was observed when considering treated versus untreated migraine. The main takeaway for clinicians is that post-menopausal women with a history of migraine appear more likely to be at risk of hypertension, even if the mechanisms behind this are currently unclear.
Disclosure
The authors report no relevant disclosures. Contact journal@neurology.org for full disclosures.
References