Introduction: The incidence of sentinel headache (SH) in the days or weeks prior to a aneurysmal subarachnoid hemorrhage (SAH) has been reported to be as high as 10-43% and SH has been linked with early re-bleeding risk.
Hypothesis: We evaluated whether ED visits for headache were more common in the month preceding a hospitalization for SAH and if this was associated with increased mortality after SAH.
Methods: We identified all hospital discharges for SAH at all licensed nonfederal hospitals in California from 2008 -11 using comprehensive data from the Office of Statewide Healthcare Planning and Development. Encounters with invalid or missing record linkage numbers (based on social security number) or for non-California residents, and those with concurrent trauma diagnoses or external injury codes were excluded. We identified the first hospitalization for SAH during the study period for each distinct patient. We then identified any ED encounters for headache without SAH during the month prior to the admission for SAH and during a one-month period exactly one year prior to the index admission for SAH.
Results: A total of 7,723 patients that were hospitalized for non-traumatic SAH during the study period met study eligibility criteria (mean age 59 years [SD 16], 62% female). A majority were white (62%) and non-Hispanic (73%), and 14% were Asian/Pacific Islander and 9% were black. Just 33 (0.4%) SAH patients had had an ED visit for headache in the preceding month compared to 2 ED visits (0.03%) for headache during a month-long period one-year prior to the hospitalization for SAH (RR 16.5, 95% CI 4.0-68, p<0.0001). SAH patients with a recent ED visit for headache had a similar length of hospital stay (10 vs 9.1 days, p=0.27), but were younger (59 vs 49 years, p=0.0002) had lower 30-day mortality (3.0% vs. 22%, p= 0.005), and were more likely to be discharged directly home (81% vs. 44%, p<0.001).
Conclusion: We identified very few ED visits for headache in the month prior to a hospitalization for aneurysmal SAH, and SAH patients who had visited the ED for headache had lower mortality and better outcomes, though SAH patients with sentinel headache who did not visit the ED were not captured in our analysis.