EBQ:Worst headache and subarachnoid hemorrhage

Complete Journal Club Article

Linn FH, Wijdicks EF, van der Graaf Y, Weerdesteyn-van Vliet FA, Bartelds AI, van Gijn J.. "Headache Characteristics in Subarachnoid Haemorrhage and Benign Thunderclap Headache". J Neurol Neurosurg Psychiatry. 1998. 65(5):791-793.
PubMed

Clinical Question

Can "worst headache of life" or specific headache characteristics reliably distinguish subarachnoid hemorrhage from benign thunderclap headache?

Conclusion

• No single headache characteristic reliably distinguishes SAH from benign thunderclap headache
• "Worst headache of life" alone has poor specificity for SAH
• Further diagnostic workup (CT, LP) is required regardless of headache characteristics when SAH is suspected

Major Points

• The study compared headache features in patients with confirmed SAH vs benign thunderclap headache
• Headache severity, onset pattern (sudden vs gradual), associated symptoms (nausea, vomiting, LOC) overlapped significantly between groups
• Approximately 12% of patients presenting with "worst headache" had SAH
• Neither the location nor the quality of headache was discriminating
• The study reinforced the need for objective diagnostic testing (CT followed by LP if CT negative) rather than relying on headache phenomenology

Study Design

• Prospective cohort study
• University Medical Center Utrecht, Netherlands
• N = 148 patients with sudden severe headache
• All patients underwent CT and lumbar puncture
• Primary Outcome: headache characteristics that discriminate SAH from benign thunderclap headache

Population

Inclusion Criteria

• Adults presenting with sudden onset severe headache (thunderclap headache)
• Headache reaching maximal intensity within seconds to minutes

Exclusion Criteria

• Headache with obvious secondary cause other than SAH (e.g., meningitis, trauma)
• Recurrent primary headache disorders with typical pattern

Interventions

• No therapeutic intervention; diagnostic accuracy study
• All patients underwent standardized headache assessment, non-contrast CT head, and lumbar puncture
• SAH was confirmed by CT findings or xanthochromia on CSF analysis

Outcomes

Primary Outcome

• No headache characteristic was independently predictive of SAH vs benign thunderclap headache
• Proportion with SAH: approximately 12% of patients with worst headache

Secondary Outcomes

• Overlap in headache features between SAH and benign thunderclap headache:
  • Sudden onset: present in both groups
  • Occipital location: similar frequency
  • Associated neck stiffness: more common in SAH but present in benign thunderclap
  • Vomiting: more common in SAH but not discriminating

Criticisms

• Relatively small sample size limits statistical power for subgroup analyses
• Single-center study in a Dutch referral population
• The definition of "thunderclap headache" may vary between practitioners
• Selection bias: patients with milder headaches who may represent earlier SAH presentations may not have been included
• The study did not evaluate modern risk stratification tools (e.g., Ottawa SAH Rule)

Funding

• Netherlands Heart Foundation

See Also

• Subarachnoid hemorrhage
• Thunderclap headache
• EBQ:Perry Subarachnoid Haemorrhage Study