Cost-effectiveness analysis of CTA and LP for evaluation of suspected SAH after negative non-contrast CT

• We model two strategies, CTA and LP, in examining thunderclap headache patients.
• Base case calculation and probabilistic sensitivity analysis are performed.
• We assess and compare costs and utilities of both strategies.
• LP has a lower cost and higher utility than CTA, and should be recommended.

ObjectivesDiagnostic workup of patients presenting with thunderclap headache and negative initial head CT remains a challenge, with most commonly employed strategies being lumbar puncture (LP) and CT angiography (CTA). The objective of this study was to determine the cost-effectiveness of these options.Patients and methodsA decision model was designed using clinical probabilities, costs, and utilities from published values in the literature. Base case analysis and Monte Carlo simulation were performed using the model to determine the cost-effectiveness of both options.ResultsCTA was associated with an expected cost of $747 and an expected utility of 0.798603029. In comparison, LP was associated with a cost of $504 and an expected utility of 0.799259526, making it the optimal strategy from both the cost and the utility perspectives. LP was also the more cost-effective strategy in all iterations in the Monte Carlo simulation. A sensitivity analysis showed that with the 2014 US Medicare reimbursement values, LP would remain the more cost-effective strategy unless its cost exceeded 4 times its current value.ConclusionLP should remain the preferred strategy for evaluation of SAH in patients presenting with thunderclap headache and negative non-contrast head CT. CTA is not an effective replacement, from either a utility or cost perspective.