The impact of headache disorders on COVID-19 survival: a world population-based analysis

Abstract

Importance: COVID-19 has not impacted people or countries uniformly. This disparity has prompted investigations to identify clinical and genetic predictors of COVID-19 mortality. Headache, a COVID-19 symptom, has been associated with positive disease prognosis. It is logical to consider whether primary headache disorders, among the most prevalent and disabling diseases globally, may also be associated with reduced viral mortality and thereby may have arisen as adaptive host defences. Objective: To study the relationship between COVID-19 mortality and primary headache disorders. Main outcome measure: Using a generalized additive model regression (GAM), we analysed data across 171 nations to identify variables which impact COVID-19 mortality rates (demographics, national wealth and government effectiveness, pandemic management indexes, latitude of the country's capital, prevalence of headache disorders and other diseases). We performed similar analyses of seasonal influenza mortality. Separately, we meta-analysed studies of COVID-19 inpatient survival reporting headache, using PRISMA guidelines. Results: In the global population-level analysis, we observed that a higher prevalence of headache disorders was associated with a higher COVID-19 mortality rate, and represented the main variable contributing to differences in COVID-19 mortality rates between countries (37.8%; F value=10.68). By contrast, we observed a negative trend between the prevalence of headache disorders and influenza death rates. Controversially, when considering headache as a symptom of COVID-19, in the 48 meta-analysed studies we observed a significantly higher risk ratio of survival (RR:2.178 [1.882-2.520], p<0.0001) among COVID-19 inpatients with headache. Conclusions and Relevance: Headache as a primary disorder is more prevalent in nations with higher COVID-19 mortality, whereas headache as a COVID-19 symptom is associated with enhanced survival. Further studies should clarify whether primary headache disorders represent a risk factor for mortality for COVID-19 or, rather, whether this association reflects evolutionary adaptive processes to enhance survival that, in the case of COVID-19, are insufficiently protective.

Living with a vestibular disorder during the Covid-19 pandemic

“…Further, self-ratings of general health and autonomic-anxiety symptoms were worse amongst the 22 respondents who thought they had been infected with Covid-19, compared to those who had not been infected. The changes reported by our sample are consistent with reports of audio-vestibular symptoms in confirmed Covid-19 cases [17], as well as complex interactions between Covid-19 and pre-existing neurological conditions including migraine [16], where there is a higher likelihood of Covid symptomology and reduced wellbeing.…”

“…Signs of peripheral and central nervous system complications (e.g., encephalopathy, stroke, seizures) and neurological symptoms (e.g., anosmia, headache) have been reported during and after the Covid-19 infection [13] with vertigo, dizziness, tinnitus and hearing loss [2,14] commonly described. Another important problem is the finding that those with a history of migraine, a disorder commonly accompanied by vestibular symptomology, appear to have a higher likelihood of Covid-19 infection, and subsequently report more frequent symptoms than those without migraine [15,16]. As yet, the causes and origins of these vestibular problems are unclear; Covid-19 may directly damage the central nervous system and inner ear organs, or trigger systemic immune responses through a viral infection that affects the vestibular system less specifically [17].…”

Headache as a Symptom of COVID-19: Narrative Review of 1-Year Research

“…The presence of headache has been associated with better COVID-19 evolution in terms of 1-week shorter COVID-19 disease duration [13•] and was inversely associated with worse outcomes in one study involving 1000 patients attended at the ER [23]. Two studies also observed that headache was associated with lower mortality [12•], findings confirmed by a recent meta-analysis showing a significantly higher risk ratio of survival COVID-19 in patients with headache [24].…”

“…Investigating primary headache disorders in the context of a viral infection will be even more relevant in the future, considering that COVID-19 studies have observed that headache as a symptom of the acute phase of the infection is associated with lower mortality. It is therefore logical to wonder whether primary headache disorders as well may be protective in viral infections [24]. In that case, questions may raise on whether they have emerged as adaptive responses in human evolution to enhance survival and consequently genetically selected in the population in response to certain stimuli such as viruses [24].…”

“…It is therefore logical to wonder whether primary headache disorders as well may be protective in viral infections [24]. In that case, questions may raise on whether they have emerged as adaptive responses in human evolution to enhance survival and consequently genetically selected in the population in response to certain stimuli such as viruses [24]. Genetic studies on COVID-19 will offer the opportunity to evaluate the risk and severity of the SARS-CoV-2 infection in specific populations such the ones with headache as a symptom of the disease or as a comorbid disorder, thus clarifying their mutual relationships.…”