Cognitive outcomes more than 5 years after temporal lobe epilepsy surgery: Remarkable functional recovery when seizures are controlled

Abstract

Epilepsy surgery can be a successful treatment option for temporal lobe epilepsy but there are concerns about accelerated memory decline in long-term follow-up. Method: 161 adult operated (77 right, 84 left temporal resections) versus a heterogeneous group of 208 nonoperated patients with focal epilepsies were consecutively recruited and re-evaluated focusing on memory, executive functions, and vocational outcome after follow-up intervals of > 5 years (5-22 years, mean 8 ± 3 years). Results: Major losses in the operated group manifest early, at one-year follow-up. Few patients declined further. Long-term changes after surgery did not differ from those observed without surgery. The factor "surgery" caused verbal memory decline, "seizure freedom" (operated 48%, non-operated 17%) was associated with recovery of verbal memory, and "drug reduction" positively affected the course of executive functions. In terms of the critical function of verbal memory, only 3-17% of seizure-free patients showed long-term decline whereas 16-20% showed improvement (operated and non-operated). Persistent seizures were associated with decline in 12-37% and improvement in 4-12% of patients. Improvement was related to longer retest intervals and was stronger in younger patients. Independent of surgery or seizure outcome, the vocational status remained unchanged or change was negative (22%) rather than positive (3%). Conclusions: Patients' cognitive course 5-22 years after surgery is stable and may even be positive if epilepsy is controlled and drug load reduced. Depending on seizure outcome, recovery is more frequently observed than continuing decline. Recovery, however, takes time and age is a limiting factor.

Very long-term outcome in resected and non-resected patients with temporal lobe epilepsy with medial temporal lobe sclerosis: A multiple case-study

“…Besides these differences, comparable scores of the QOLIE were found for the remaining subscales across both patient groups ( Fig. 2A; Grewe, et al Inspecting our individual patient's data revealed that in general, higher QoL-scores for the RP as compared to the NRP were found for the subgroup of the seizure-free patients (ID 7,8,9). In contrast, non-seizure-free RP (ID 4,5,6) had comparable or even lower QoL-scores than the NRP.…”

“…2C). Likewise, cognitive complaints in the FLei (and the QOLIE-32) were particularly low for the seizure-free RP (ID 7, 8,9) who also demonstrated the lowest scores in almost all remaining subscales of the QOLIE-32. Conflicting results between our and Edelvik et al's study may emerge from methodological differences.…”

“…So far, only a limited number of studies report seizure and cognitive outcome at long-term intervals, i.e., > 5 years postoperatively [6]. In spite of recent publications on the very long-term psychosocial [7] and cognitive [8] outcome after epilepsy surgery, the comprehensive very long-term (i.e., ≥15 years) assessment including cognitive, seizure, and subjective (i.e., psychosocial and mood) variables after TLE surgery has been broadly neglected in the literature so far. There are two potential hypotheses: Ongoing seizures may trigger an accelerated cognitive decline in the course of a chronic epilepsy, whereas seizure-freedom (or longer seizure-free intervals) may protect from this [9][10][11].…”

“…The key challenge is, however, to counsel patients who are evaluated for aTLR around the age of 30 years -the typical population in adult presurgical cohorts [6]. This also holds for the aforementioned studies [8,12,13,16] in which the patients' average age at long-term examination was mostly below the age of 40 years. As physiological cognitive decline will usually not be observed before the fifth decade of life, follow-up intervals of at least 15 years should be considered to examine a potential accelerated cognitive decline in TLE.…”

“…We sought to compare the very long-term seizure, cognitive, and psycho-social outcomes in patients after aTLR compared to non-resected patients with TLE. Facing the fact that prospective randomized trials considering very long-term outcome will presumably not be available in the near future due to recall difficulties [8], we had the chance to evaluate very long-term outcome in a case series of older patients with TLE. This offered the opportunity to comprehensively examine individual long-term outcome and trajectories.…”