Major depressive episode, cognition, and epilepsy

Systematic literature review of the humanistic and economic burden of focal epilepsy and primary generalized tonic-clonic seizures in adults

This systematic literature review (SLR) assessed the humanistic and economic burden of focal epilepsy and primary generalized tonic-clonic seizures (PGTCS) in adults to evaluate these domains in both populations and identify evidence gaps to inform future research. A search was conducted on December 7, 2022, using MEDLINE and Embase to identify studies published from 2012 onwards reporting humanistic burden (patient-reported or caregiver-reported outcomes or utilities, qualitative evaluations), economic burden (productivity loss, caregiver and societal costs of epilepsy), and sleep-related outcomes. Of the 2830 citations identified, 136 were included. Most studies were in the focal epilepsy population; very few studies reported outcomes in the PGTCS population. The presence of epilepsy-specific instruments varied based on the domain evaluated. Epilepsy exerted considerable humanistic and economic burden. Indicators of poor disease control (e.g., high seizure frequency, resistance to anti-seizure medications, polypharmacy) increased epilepsy burden. Seizure frequency and type, disease severity, and polypharmacy also affected work productivity. Adults with epilepsy, particularly focal epilepsy, reported higher indirect costs, more sick days accrued, and early entry into retirement. Caregivers similarly reported high productivity loss and absenteeism related to caregiving duties. The results of this SLR highlight the high humanistic and economic burden of focal epilepsy and PGTCS, although limited data were available for the PGTCS population. The results include patient-reported outcome data specific to focal epilepsy and PGTCS, expanding the limited humanistic burden evidence identified in previous reviews, and show the effect of poor disease control on individuals' lives and as a driver of indirect costs. PLAIN LANGUAGE SUMMARY: Our systematic literature review identified studies that evaluated the impact of focal epilepsy and primary generalized tonic-clonic seizures on patients and their caregivers. We found that focal epilepsy negatively impacted patients' mental health and sleep and was associated with higher indirect costs and lower work productivity in people with more severe disease. The impact of primary generalized tonic-clonic seizures on patients was rarely reported, and future research is needed.

Evaluating the prevalence and risk factors for depression in patients with temporal lobe epilepsy with hippocampal sclerosis: A cross-sectional multicenter study

BACKGROUND

Epilepsy frequently accompanies Major Depressive Disorder (MDD). Notably, people with temporal lobe epilepsy and hippocampal sclerosis may face an increased susceptibility to MDD, as evidence indicates the involvement of the limbic system in the development of emotional symptoms.

OBJECTIVES

To determine the prevalence and predictors of depression in temporal lobe epilepsy with hippocampal sclerosis (TLE-HS) and compare them to those of other epilepsy types.

METHODS

A sample of 293 epilepsy patients, including 159 non-TLE-HS and 134 TLE-HS, were recruited from three hospitals. Of these, 215 completed a two-section electronic survey. The first section collected demographic and epilepsy data, while the second used the Arabic version of the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E).

RESULTS

Of 215 patients, 104 (48%) had TLE-HS-38 with right TLE-HS (37%), 56 with left TLE-HS (54%), and 10 with bilateral TLE-HS (10%). The prevalence and severity of depression was assessed with an NDDI-E score of 15 or higher identified 35 patients (16%) with MDD. Valproic acid and lamotrigine were associated with higher NDDI-E scores. No such associations were found for levetiracetam or carbamazepine. Polytherapy in TLE-HS showed a significant correlation with daily poor concentration.

CONCLUSION

We explored the differences in depression prevalence between TLE-HS and other epilepsy types and concluded they are minimal but slightly higher in TLE-HS. Predictors of depression such as seizure frequency and disease duration influenced MDD prevalence in TLE-HS. Lamotrigine and valproate were linked to higher NDDI-E scores.

Sex differences in the association of plasma cytokines and neurocognition in first-episode major depressive disorder

BACKGROUND

Peripheral cytokines were found to be involved in the pathophysiology of neurocognition in individuals with major depressive disorder (MDD). However, whether there are sex differences in this association between cytokines and cognition in MDD remains unknown. Our aim is to examine sex differences in the relationship between plasma cytokines and cognition in MDD.

METHOD

One hundred and twenty-seven first episode drug naïve patients with MDD and sixty healthy controls (HCs) were recruited for present study. The MATRICS Consensus Cognitive Battery was administered to measure the cognition. Plasma concentrations of nineteen cytokines were measured using high sensitivity multiplex bead-based assays.

RESULTS

Both female and male patients with MDD had significant cognitive impairment in verbal learning and visual learning and had higher levels of a range of cytokines than HCs (all p < 0.05). Female patients performed worse in trail making (F = 4.442, p = 0.018) and had higher concentration of interleukin (IL)-4 (F = 7.775, p = 0.006) than males. In female MDD, a significant positive association between category frequency and level of IL-4 was observed (B = 8.040, p = 0.031). However, this association was not present in male MDD or HCs (p > 0.05).

LIMITATION

Present study used a cross-sectional design.

CONCLUSION

Female MDD patients had worse trail making performance and higher level of IL-4 than males. The elevated IL-4 in female MDD was positively associated with category fluency, suggesting that IL-4 may be involved in the pathophysiology related to specific cognitive domain in female MDD patients.

Cognitive decline and quality of life after resective epilepsy surgery

OBJECTIVES

The objectives of this study were to examine the association between cognitive decline and quality of life (QoL) change in a large sample of individuals with drug-resistant epilepsy who underwent resective surgery and to examine whether the association between cognitive decline and QoL is differentially affected by seizure classification outcome (Engel Class 1 vs. 2-4) or side of surgery (left vs. right hemisphere).

MATERIALS AND METHODS

The sample comprised 224 adults (ages ≥ 18) with drug-resistant focal epilepsy treated with resective surgery who underwent comprehensive pre-operative and post-operative evaluations including neuropsychological testing and the Quality of Life in Epilepsy Inventory - 31 between 1991 and 2020. Linear mixed-effects models were fit to examine subject-specific trajectories and assess the effects of time (pre- to post-operative), cognitive decline (number of measures that meaningfully declined), and the interaction between time and cognitive decline on pre- to post-operative change in QoL.

RESULTS

Increases in QoL following resection were observed (B = -10.72 [SE = 1.22], p < .001; mean difference between time point 1 and time point 2 QoL rating = 8.11). There was also a main effect of cognitive decline on QoL (B = -.85 [SE = .27], p = .002). Follow-up analyses showed that the number of cognitive measures that declined was significantly associated with post-surgical QoL, (r = -.20 p = .003), but not pre-surgical QoL, (r = -.04 p = .594), and with pre-to post-surgery raw change in QoL score, (r = -.18 p = .009). A cognitive decline by time point interaction was observed, such that those who had greater cognitive decline had less improvement in overall QoL following resection (B = .72 [SE = .27], p = .009). Similar results were observed within the Engel Class 1 outcome subgroup. However, within the Engel Class 2-4 outcome subgroup, QoL improved following resection, but there was no main effect of cognitive decline or interaction between cognitive decline and time point on QoL change. There was no main effect of resection hemisphere on overall QoL, nor were there interactions with hemisphere by time, hemisphere by cognitive decline, or hemisphere by time by cognitive decline.

CONCLUSIONS

Quality of life improves following epilepsy surgery. Participants who had cognitive decline across a greater number of measures experienced less improvement in QoL post-operatively overall, but there was no clear pattern of domain-specific cognitive decline associated with change in QoL. Our results indicate that cognitive decline in a diffuse set of cognitive domains negatively influences post-operative QoL, particularly for those who experience good seizure outcomes (i.e., seizure freedom), regardless of the site or side of resection.

One-Year Analysis of Risk Factors Associated With Cognitive Impairment in Newly Diagnosed Epilepsy in Adults

Cognitive impairment (CI) occurs in people with epilepsy, affecting their quality of life. This study aimed to identify factors associated with CI in adult patients with newly diagnosed epilepsy. Additionally, we sought to determine whether any particular cognitive function is impaired predominantly by anti-seizure medications or by other factors. We enrolled 229 patients with newly diagnosed epilepsy and 191 participants were followed up for 1 y. We used the Montreal Cognitive Assessment as a tool to quantify CI. The sub-item scores were also collected to assess whether any aspects of CI are predominantly affected by anti-seizure medication treatment. Subjective memory decline due to anti-seizure medications was also recorded. One-hundred-and-two participants (44.5%) had CI onset before anti-seizure medication treatment. Aging, low education level, stroke or brain surgery etiology, and anxious symptoms were identified as risk factors for CI before anti-seizure medications use. Brain surgery for the young, anxious status for the middle-aged, and depressive status for the elderly were risk factors for CI at different ages. The elderly PWE had worse memory than the others. PWE with TLE had worse cognition, especially in memory and naming. The overall impact of anti-seizure medications on cognition was mild. Refractory epilepsy was a predictor of cognitive decline. Subjective memory decline was predicted by high-risk treatment and by a finding of refractory epilepsy. Clarifying the risk factors for CI can help the physician to assess the probable risk of CI for each individual before the start of anti-seizure medication treatment, which may lead to better compliance.

Depression could modulate neuropsychological status in epilepsy

While cognition and depression have often been studied in patients with epilepsy, only a few studies have so far attempted to link these two domains, and more specifically to investigate the specific impact of depression on cognition in epilepsy. In this review, we performed an extensive search of the literature database to provide a better understanding of this subject. Using several inclusion criteria (adult population, quantitative depression/neuropsychological assessment, statistical analyses of the impact of depression on cognitive scores, patients with epilepsy (PWE) and no other neurological disease, and studies including at least 20 patients), we identified 20 articles (out of 712 search results) that investigated both depression and cognition in PWE. Their results were summarized using a narrative and descriptive approach. This review highlights a variable impact of depression on cognition in PWE, depending on the laterality of the seizure onset zone, the type of epilepsy and the surgical context. We emphasize the need for a systematic depression assessment in these patients, especially since depressed PWE will benefit from prompt and appropriate care to help them avoid cognitive decline, particularly in a surgical context.