Cost-Effectiveness of Anterior Temporal Lobectomy

ABSTRACT & COMMENTARY
Source: Langfitt J. Cost-effectiveness of anterior temporal lobectomy in medically intractable complex partial epilepsy. Epilepsia 1997;38:154-163.

With more attention being paid to cost-effective medicine, expensive therapies such as epilepsy surgery have come under considerable scrutiny. Langfitt has now published a new model to study the cost-effectiveness of anterior temporal lobectomy for medication-resistant temporal lobe epilepsy.

His model was based on the average expenses for the treatment of seizure disorders for patients of the Comprehensive Epilepsy Program at the University of Rochester, New York. Costs for pre-surgical evaluation, anterior temporal lobectomy, and all subsequent follow-up medical care until death were estimated to be $109,362. For only medical management over the same time interval, the estimated cost was $84,276.

Langfitt also employed a measure called the "marginal cost-effectiveness ratio" (MCER) to compare anterior temporal lobectomy with continuing medical management of seizures. The method for deriving this MCER value is not important to the general neurologist; in essence, it represents the cost difference between surgical and medical treatments, divided by the difference between surgical and medical treatments on a standardized health-related quality of life measure. Lower marginal cost-effectiveness ratios, either due to little difference in costs between the treatments, or due to surgery yielding substantially better quality of life, indicate greater cost- effectiveness. Based on his literature review, Langfitt found that MCERs of $19,000 or less correlate with therapies that are generally viewed by society as treatments that are "worth the expense." The MCER for anterior temporal lobectomy was $15,581 (i.e., definitely falling into the "worth the expense" category).

COMMENTARY

Based on his model, Langfitt concluded that anterior temporal lobectomy is costlier than continuing medical management of seizures but that the quality of life benefits of epilepsy surgery warrant the incremental expenses. Several additional points further strengthen his point of view.

Langfitt’s model only included direct medical costs. While only direct medical costs are of interest to health insurance companies, other additional costs are of interest to patients, health care providers, and society at large. Begley and colleagues (Epilepsia 1994;35:1230-1243) estimated that indirect societal costs for public assistance of a person disabled by epilepsy amount to three times the direct costs of medical care. The indirect costs of severe seizure disorders are reduced by epilepsy surgery, since Sperling and colleagues (JAMA 1996;276:470-475) found that temporal lobectomy for intractable temporal lobe epilepsy significantly improved employment rates post-operatively (see Neuro Alert 1996;15:30-31).

Sperling et al and Vickrey et al (Lancet 1995; 346:1445-1449) reported that epilepsy surgery significantly reduced the high mortality rate associated with persistent medication- resistant seizures. This in and of itself increases the desirability of epilepsy surgery. Furthermore, Langfitt assumed similar life spans for the surgical and medical treatment groups in his model, based on an older study of Guldvog et al (Epilepsia 1991;32:375-388). If longer life spans were to be added into Langfitt’s quality-of-life measures, this would further lower the MCER of anterior temporal lobectomy (i.e., increase desirability and cost-effectiveness).

I believe that, in 1997, anterior temporal lobectomy should be considered the standard of care to treat medication-resistant temporal lobe epilepsy (TLE), based on anti-epileptic effectiveness, long-term reductions in seizure-associated mortality, and cost-effectiveness. However, almost shockingly, even today epilepsy surgery programs operate—on average—on only one patient per month (Commission on Neurosurgery of Epilepsy. Epilepsia 1997;38:249-255). Practicing neurologists need to refer severe TLE patients promptly for temporal lobectomy, rather than persisting with less effective medical management. —drl