Vasoconstriction and long-term headache in reversible cerebral vasoconstriction syndrome

Angiographic vasoconstriction in reversible cerebral vasoconstriction syndrome (RCVS) is often undetectable at symptom onset and the diagnosis relies on clinical presentation. Although thunderclap headache is a hallmark feature of RCVS, the incidence and predictors of long-term headaches (LTH) are incompletely understood. Our study aims were twofold: to examine the sensitivity and specificity of a recently developed score (RCVS₂) for vasoconstriction detection in a real-world clinical context and describe the incidence and predictors of LTH beyond the acute phase of RCVS.

Retrospective analysis of consecutive patients with clinical diagnosis of RCVS in a tertiary hospital between 2017 and 2021. We examined associations between demographic factors, comorbidities, medications, imaging characteristics, and LTH (defined as at least one episode present at greater than 6-months follow-up necessitating medication). We separately examined the association between RCVS₂ score and angiographic vasoconstriction and computed its sensitivity, specificity, and negative and positive predictive value based on established cutoffs (certain ≥ 5, negative ≤ 2).

We included 55 patients, 50.5 (± 13.7) years; 41 (75%) female. 25 (49%) patients had LTH; only prior history of headache was significantly associated with LTH [OR 4.3, 95% CI (1.1-16.2), p = 0.03]. We found a significant association between RCVS₂ score and angiographic vasoconstriction [OR 1.49, 95% CI (1.18-1.88), p = 0.001]; sensitivity, specificity, and positive and negative predictive value were 64%, 94%, 95% and 58% respectively.

Approximately 50% of RCVS patients experienced LTH; only prior headache history was associated with its incidence. The RCVS2 score had a significant association with high specificity and positive predictive value for angiographic vasoconstriction in our cohort, validating its utility in improving the accuracy of diagnosis in the clinical setting.