Headaches that kill: a retrospective study of incidence, etiology and clinical features in cases of sudden death.

OBJECTIVE: The study objective was to analyze cases of sudden death that presented to the National Deptartment of Clinical Neurosciences, Ireland, over a 10-year period (1997-2006) where headache was the presenting symptom.

BACKGROUND: Headache is a common yet challenging presentation in clinical neurology. In the vast majority of cases, the cause is trivial and reversible-however, in a few patients it may be indicative of a more sinister intracranial process. Recognizing associated "red flag" features and identifying possible life-threatening causes are crucial in ensuring prompt and appropriate intervention.

DESIGN/METHODS: A retrospective study/database of all autopsy cases presenting to the Neuropathology Department in Beaumont Hospital, Dublin, was carried out for the period 1997-2006. Cases were selected with headache as the presenting clinical feature. Traumatic head injuries or known central nervous system (CNS) disorders were excluded. Autopsy and medical reports were reviewed to identify associated red flag features at initial presentation according to the International Classification of Headache Diseases, second edition (ICHD-II) criteria.

RESULTS: Fifty-five autopsy cases out of a total of 499 complying with selection criteria were reviewed. Over the 10-year-study period, the number of cases of fatal headaches over time were negatively correlated. The most commonly associated red flag symptoms included age over 50: loss of consciousness and collapse, and worst/thunderclap character of headache. Cause of death at autopsy comprised vascular events 60.4% (N = 29), primary brain tumours/cysts 16.7% (N = 8) and meningitis 6.25% (N = 3). Aneurysms accounted for the majority of vascular cases 22.9% (N = 11), with loss of consciousness, occipital headache, neck pain and a focal neurological deficit seen more commonly in this subset of cases.

CONCLUSIONS: Sudden-onset headache is a common and often alarming presentation. The majority of cases are of a benign nature; however, a small proportion may be indicative of a catastrophic etiology. Documenting "red flags" on initial presentation is crucial to acutely identify and treat those at highest risk. The results demonstrate an improving trend among clinicians in recognizing and initiating appropriate interventions in these patients, and highlights particular red flag features common in cases of fatal headaches.