Memory performance in older adults before and after temporal lobectomy for pharmacoresistant epilepsy

Role of resective surgery in patients older than 60 years with therapy-resistant epilepsy

OBJECTIVE

Epilepsy surgery for older adults is controversial owing to their longer duration of epilepsy and perceived higher surgical risk. However, because of an aging population and documented benefit of epilepsy surgery, surgery is considered more frequently for these patients. The authors' objective was to analyze the role of resective surgery in patients older than 60 years and to assess outcomes and safety.

METHODS

The authors conducted a retrospective analysis of 595 patients who underwent resective epilepsy surgery at their center from 1999 to 2018. Thirty-one patients aged 60 years or older were identified. Sixty patients younger than 60 years were randomly selected as controls. Population characteristics, results of presurgical evaluations, outcomes, and complications were analyzed.

RESULTS

No significant differences were found between the groups in terms of hemisphere dominance, side of surgery, presence of a lesion, and incidence of temporal lobe epilepsy. Epilepsy duration was greater in the older cohort (p = 0.019), and invasive EEG was more commonly employed in younger patients (p = 0.030). The rates of Engel class I outcome at 6 months, 1 year, and 2 years were 89.7%, 96.2%, and 94.7% for the older group and 75% (p = 0.159), 67.3% (p = 0.004), and 75.8% (p = 0.130) for the younger group, respectively. The proportion of seizure-free patients was greatest among those with temporal lobe epilepsy, particularly in the older group. Neurological complication rates did not differ significantly between groups, however medical and other minor complications occurred more frequently in the older group.

CONCLUSIONS

Patients older than 60 years had equal or better outcomes at 1 year after epilepsy surgery than younger patients. A trend toward a greater proportion of patients with lesional temporal lobe epilepsy was found in the older group. These results suggest that good seizure outcomes can be obtained in older patients despite longer duration of epilepsy.

Resective epilepsy surgery in patients aged 50years and older - a retrospective study regarding seizure outcome, memory performance, and psychopathology

PURPOSE

To assess clinical and demographic characteristics in two cohorts of elderly patients with drug-resistant focal epilepsy, undergoing resective epilepsy surgery (RES). Further, to determine seizure, neuropsychological, and mental health outcomes after RES and evaluate possible influencing factors.

METHODS

Consecutive patients aged ≥50 years with temporal lobe epilepsy (TLE) who underwent curative RES in the Hamburg epilepsy surgery program (2004-2017) were identified. Data were retrospectively analyzed. Seizure outcome was classified according to ILAE and Engel outcome scales in patients with first-time surgeries and with reoperations. Previously reported predictors of the seizure outcome were evaluated using regression analyses. Changes in verbal memory were assessed for patients with complete pre- and postoperative datasets (n=30) using repeated-measures analysis of variance. For evaluation of possible predictors of psychopathologic changes after RES a regression analysis was conducted.

RESULTS

Fifty-one elderly patients underwent RES of the temporal lobe, including twelve aged ≥60 years, and five with reoperations. After one year, 65% of the patients with first-time surgeries were seizure free and 91% had a favorable outcome. At last follow-up, 49% were seizure free since surgery. Three reoperated patients had an Engel I outcome. Seizure outcome was not dependent on age at surgery, duration of epilepsy, or other evaluated variables. There was no significant decline in the memory performance after surgery. Significant improvements in mental health were found.

CONCLUSION

RES for drug-resistant TLE is safe, effective, and improves mental health also in patients aged ≥ 50 years. Thus, it should be evaluated as the treatment of choice also in this age group.

Diagnosing cognitive disorders in older adults with epilepsy

OBJECTIVE

To characterize the nature and prevalence of cognitive disorders in older adults with temporal lobe epilepsy (TLE) and compare their cognitive profiles to patients with amnestic mild cognitive impairment (ie, aMCI).

METHODS

Seventy-one older patients with TLE, 77 aMCI, and 69 normal aging controls (NACs), all 55-80 years of age, completed neuropsychological measures of memory, language, executive function, and processing speed. An actuarial neuropsychological method designed to diagnose MCI was applied to individual patients to identify older adults with TLE who met diagnostic criteria for MCI (TLE-MCI). A linear classifier was performed to evaluate how well the diagnostic criteria differentiated patients with TLE-MCI from aMCI. In TLE, the contribution of epilepsy-related and vascular risk factors to cognitive impairment was evaluated using multiple regression.

RESULTS

Forty-three TLE patients (60%) met criteria for TLE-MCI, demonstrating marked deficits in both memory and language. When patients were analyzed according to age at seizure onset, 63% of those with an early onset (<50 years) versus 56% of those with late onset (≥ 50 years) met criteria for TLE-MCI. A classification model between TLE-MCI and aMCI correctly classified 81.1% (90.6% specificity, 61.3% sensitivity) of the cohort based on neuropsychological scores. Whereas TLE-MCI showed greater deficits in language relative to aMCI, patients with aMCI showed greater rapid forgetting on memory measures. Both epilepsy-related risk factors and the presence of leukoaraiosis on MRI contributed to impairment profiles in TLE-MCI.

SIGNIFICANCE

Cognitive impairment is a common comorbidity in epilepsy and it presents in a substantial number of older adults with TLE. Although the underlying etiologies are unknown in many patients, the TLE-MCI phenotype may be secondary to an accumulation of epilepsy and vascular risk factors, signal the onset of a neurodegenerative disease, or represent a combination of factors.

Surgery for temporal lobe epilepsy in the elderly: Improving quality of life despite cognitive impairment

INTRODUCTION

Temporal lobe epilepsy (TLE) surgery is still underutilized, especially in the elderly population because of concerns related to postoperative complication rate and cognitive deterioration. The aim of the study was to evaluate surgical data, quality of life and neuropsychological outcome in elderly patients, who underwent resective surgery for drug resistant TLE.

METHODS AND MATERIALS

All patients underwent standardized presurgical assessment including clinical, neuroradiological, neuropsychological, and EEG examination. Elderly were considered all patients being 50 years or above (mean 56 yr., range 50-71 yr.). Neuropsychology was assessed before and after surgery, health-related quality of life (HRQOL) only after surgery.

RESULTS

A total of 94 consecutive elderly patients were analyzed. Temporo-mesial resections were performed in 85 patients (90 %). Seizure outcome was available in all patients with a mean follow-up of 5.2 years (1.2-19 ± 3.75 years). 57 patients (60.6 %) were completely seizure free (ILAE 1). The overall morbidity was 10 % including 5 surgical complications and 5 permanent neurological deficits. Neuropsychological assessments in 60 patients showed considerable preoperative impairment, losses in different domains in 25-45 % and gains in about 25 % of the patients. Postoperative HRQOL data was available in 75 patients, revealing significant increase of HRQOL in all domains. Complete seizure freedom was the strongest predictor for postoperative HRQOL (p < 0.001).

CONCLUSION

Surgery for drug resistant temporal lobe epilepsy is a feasible option for elderly patients as seizure control rates are comparable to the younger population. The acceptable rate of permanent neurological deficits and relevant improvements in quality of life, despite considerable postoperative cognitive impairment, justify surgical resection in properly selected elderly patients.

Epilepsy in older people

Globally, as populations age there will be challenges and opportunities to deliver optimal health care to senior citizens. Epilepsy, a condition characterised by spontaneous recurrent seizures, is common in older adults (aged >65 years) and yet has received comparatively little attention in this age group. In this Review, we evaluate the underlying causes of epilepsy in older people, explore difficulties in establishing a diagnosis of epilepsy in this population, discuss appropriate antiseizure medications, and evaluate potential surgical treatment options. We consider cognitive, psychological, and psychosocial comorbidities and the effect that epilepsy might have on an older person's broader social or care network in high-income versus middle-income and low-income countries. We emphasise the need for clinical trials to be more inclusive of older people with epilepsy to help inform therapeutic decision making and discuss whether measures to improve vascular risk factors might be an important strategy to reduce the probability of developing epilepsy.

Time to push the age limit: Epilepsy surgery in patients 60 years or older

Objective

To summarize the existing literature on resective epilepsy surgery (RES) in older adults (≥60 years old) and examine seizure and neuropsychological outcomes in a single‐center large cohort of older adults undergoing RES and their comparison to a consecutive, younger (25‐ to45‐year‐old) adult population who underwent RES in routine clinical practice.

Methods

First, a comprehensive literature review was performed. Then, we identified older adults who underwent RES at our center (2000–2015). Outcome analysis was performed on patients who had ≥1 year of clinical follow‐up. A younger cohort of patients who underwent RES during the same period was selected for comparison. The 2 groups were compared with respect to demographic and disease variables as well as key clinical outcomes.

Results

Seizure outcomes on 58 older patients were reported in existing literature; 72% achieved Engel class I outcome ≥1 year postoperatively. Sixty‐four older adults underwent RES at our center, accounting for 2.8% of all RES during the study period. A total of 51 older adults (M_age = 65) among them had ≥1‐year clinical follow‐up; 80% achieved Engel I outcome after a mean follow‐up of 3.2 years. This was comparable to the 68% Engel class I outcome among 50 consecutive younger adults, despite later age of onset, longer epilepsy duration, and more comorbidities (all p < 0.001) among older adults. The majority (86%) of older adults were referred to our center after years of suffering from drug‐resistant epilepsy. There were no group differences in surgical complications. However, 1 older adult passed away post‐RES. There was no difference in post‐RES neuropsychological outcomes compared to younger adults, except significantly higher number of older adults showed a decline in confrontational naming.

Significance

RES in well‐selected older adults is a safe and effective therapy, and advanced age should not preclude consideration of surgical therapy in older adults with pharmacoresistant epilepsy.

Breaking the age barrier: Epilepsy surgery in septuagenarians

Resective epilepsy surgery (RES) has traditionally been offered to young patients (<50years). The reservation about offering RES to the elderly is multifactorial with their advanced age and comorbidities being the primary reason. The elderly age group (≥65years of age) is one of the fastest growing populations. The arbitrary age limits for RES need reconsideration in the face of an ever increasing elderly population. Considering such changes in demographics, we report the first case series in the literature of seven septuagenarians who underwent RES in the form of anterior temporal lobectomy (ATL). The 10-year median survival probability based on their comorbidities and age was more than 50%. Six patients had good surgical outcome (Engle I/II) with four of them being completely free of disabling seizures after a median follow-up of almost 2years. No significant medical or surgical morbidity was observed. However, three out of the four patients undergoing pre- and post-RES neuropsychological testing showed decline in memory function. Seizure-related injuries were noted in four out of seven patients and may have been a motivation to proceed with RES in our cohort. Our experience suggests that RES can be a safe and effective therapy in well-selected, septuagenarian patients with drug-resistant epilepsy. Neuropsychological outcomes after RES in this population need further evaluation.

Age at surgery as a predictor of cognitive improvements in patients with drug-resistant temporal epilepsy

Temporal lobe epilepsy (TLE) surgery is an effective procedure that can produce cognitive changes. However, the prognostic factors related with cognitive outcomes need to be better understood. The aim of the present study is to know if age at surgery is a reliable predictor of verbal memory competence and considering factors such as: hemisphere; type of surgery; pre-surgical seizure frequency; and epilepsy duration. Sixty-one typically dominant patients with drug-resistant TLE (34 with left TLE [L-TLE] and 27 with right TLE [R-TLE]) underwent a neuropsychological assessment before and a year after surgery. Results showed that R-TLE patients had better evolution in short- and long-term verbal memory and naming than L-TLE patients (for all, p >.04). L-TLE patients also more frequently showed a strong and reliable decline in these functions than R-TLE patients. No effects for gender or type of surgery were found. From a multivariate approach, patients with improvements in verbal competence underwent surgery at earlier ages and suffered epilepsy for less time (for all, p <0.4). The relevance of age at surgery was confirmed as a predictor of long-term verbal memory changes, although the frequency of partial seizures also explains, at least partially, these changes. In addition, the frequency of partial seizures explains short-term verbal memory changes. These results emphasize the importance of early intervention, independently of the resected hemisphere, in order to minimize the cognitive side-effects of epilepsy treatment, as well the need to consider cognitive functions as related processes and network dependent.

Cognitive outcomes of temporal lobe epilepsy surgery in older patients

PURPOSE

To examine the cognitive risks of temporal lobe surgery in patients aged 50 years and older.

METHODS

We analysed data from 55 patients who underwent temporal lobe surgery (26 left-sided:29 right sided) from 1988 to 2012 at our centre. Pre-surgical and one year post-operative memory and naming capacity were compared to data obtained from two younger cohorts; 185 aged 18-30 and 220 aged 31-49.

RESULTS

Pre-operative memory impairments were most marked for the oldest cohort and were associated with a longer duration of epilepsy. Naming capacity improved with age and better performance was associated with a later age at epilepsy onset. Post-operative declines were largest in older patients, achieving statistical significance for verbal memory, naming and subjective ratings. Left temporal lobe resections carried the greatest risk of memory and naming decline. Cognitive outcomes were unrelated to seizure outcome, VIQ or mood.

CONCLUSION

Our findings indicate the cognitive risks of TLE surgery are greater for older patients. Cognitive outcomes need to be considered when assessing the efficacy of epilepsy surgery in older cohorts and pre-operative performance levels need to be taken into account.

Long-term postoperative atrophy of contralateral hippocampus and cognitive function in unilateral refractory MTLE with unilateral hippocampal sclerosis

OBJECTIVE

This study aimed to evaluate long-term atrophy in contralateral hippocampal volume after surgery for unilateral MTLE, as well as the cognitive outcome for patients submitted to either selective transsylvian amygdalohippocampectomy (SelAH) or anterior temporal lobe resection (ATL).

METHODS

We performed a longitudinal study of 47 patients with MRI signs of unilateral hippocampal sclerosis (23 patients with right-sided hippocampal sclerosis) who underwent surgical treatment for MTLE. They underwent preoperative/postoperative high-resolution MRI as well as neuropsychological assessment for memory and estimated IQ. To investigate possible changes in the contralateral hippocampus of patients, we included 28 controls who underwent two MRIs at long-term intervals.

RESULTS

The volumetry using preoperative MRI showed significant hippocampal atrophy ipsilateral to the side of surgery when compared with controls (p<0.0001) but no differences in contralateral hippocampal volumes. The mean postoperative follow-up was 8.7 years (± 2.5 SD; median=8.0). Our patients were classified as Engel I (80%), Engel II (18.2%), and Engel III (1.8%). We observed a small but significant reduction in the contralateral hippocampus of patients but no volume changes in controls. Most of the patients presented small declines in both estimated IQ and memory, which were more pronounced in patients with left TLE and in those with persistent seizures. Different surgical approaches did not impose differences in seizure control or in cognitive outcome.

CONCLUSIONS

We observed small declines in cognitive scores with most of these patients, which were worse in patients with left-sided resection and in those who continued to suffer from postoperative seizures. We also demonstrated that manual volumetry can reveal a reduction in volume in the contralateral hippocampus, although this change was mild and could not be detected by visual analysis. These new findings suggest that dynamic processes continue to act after the removal of the hippocampus, and further studies with larger groups may help in understanding the underlying mechanisms.