Association between high titers of glutamic acid decarboxylase antibody and epilepsy in patients with type 1 diabetes mellitus: A cross-sectional study

Exploring the clinical connections between epilepsy and diabetes mellitus: Promising therapeutic strategies utilizing agmatine and metformin

PURPOSE

Diabetes mellitus (DM) and epilepsy and the psychological and socio-economic implications that are associated with their treatments can be quite perplexing. Metformin is an antihyperglycemic medication that is used to treat type 2 DM. In addition, metformin elicits protective actions against multiple diseases, including neurodegeneration and epilepsy. Recent studies indicate that metformin alters the resident gut microbiota in favor of species producing agmatine, an arginine metabolite which, in addition to beneficially altering metabolic pathways, is a potent neuroprotectant and neuromodulant.

METHODS

We first examine the literature for epidemiological and clinical evidences linking DM and epilepsy. Next, basing our analyses on published literature, we propose the possible complementarity of agmatine and metformin in the treatment of DM and epilepsy.

RESULTS

Our analyses of the clinical data suggest a significant association between pathogeneses of epilepsy and DM. Further, both agmatine and metformin appear to be multimodal therapeutic agents and have robust antiepileptogenic and antidiabetic properties. Data from animal and clinical studies largely support the use of metformin/agmatine as a double-edged pharmacotherapeutic agent against DM and epilepsy, particularly in their concurrent pathological occurrences.

CONCLUSION

The present review explores the evidences and available data on possible uses of metformin/agmatine as pertinent antidiabetic and antiepileptic agents. Our hope is that this will stimulate further research on the therapeutic actions of these multimodal agents, particularly for subject-specific clinical outcomes.

Type 1 diabetes and the risk of epilepsy: A meta-analysis

AIMS/INTRODUCTION

An overrepresentation of epilepsy has been suggested in patients with type 1 diabetes (T1D). This meta-analysis was conducted to evaluate if type 1 diabetes is associated with a higher incidence of epilepsy.

MATERIALS AND METHODS

Longitudinal observational studies which are relevant to the purpose of the meta-analysis were screened and obtained by searching PubMed, Embase, and Web of Science databases. Random-effects models were used when significant heterogeneity was observed; otherwise, fixed-effects models were used.

RESULTS

Six observational studies involving 10 datasets of 8,001,899 participants were included, with six datasets including children and only one dataset including older people. Among them, 100,414 (1.25%) had type 1 diabetes. During the follow-up duration of 5.4-15.2 years (mean: 9.5 years), 98,644 cases (1.23%) of epilepsy were observed. Compared with participants with normoglycemia, those with type 1 diabetes were shown to have a higher incidence of epilepsy (risk ratio [RR]: 2.41, 95% confidence interval 1.69-3.44, P < 0.001; I2  = 95%) after adjustment of potential confounding variables including age and sex. Subgroup analysis showed consistent results in nested case-control and retrospective cohort studies, and in studies of children, non-elderly adult, and older participants (P for subgroup difference = 0.42 and 0.07). In addition, a stronger association of type 1 diabetes and epilepsy was suggested in studies with follow-up duration <10 years compared with those ≥10 years (RR: 3.34 vs 1.61, P for subgroup difference < 0.001).

CONCLUSION

Patients with type 1 diabetes may have a higher risk of epilepsy, which was mainly driven by datasets including children.

Electroencephalographic abnormalities in children with type 1 diabetes mellitus: a prospective study

Background/aim

The aim herein was to investigate epileptiform discharges on electroencephalogram (EEG), their correlation with glutamic acid decarboxylase 65 autoantibody (GAD-ab) in newly diagnosed pediatric type 1 diabetes mellitus (T1DM) patients and interpret their medium-term utility in predicting epilepsy.

Materials and methods

Children presenting with T1DM between July 2018 and December 2019 were included in this prospective longitudinal study. Patients with a history of head injury, chronic illness, neurological disorder, seizure, autism, or encephalopathy were excluded. EEGs were obtained within the first 7 days of diagnosis and later reviewed by a pediatric neurologist. All of the children were clinically followed-up in pediatric endocrinology and neurology clinics for 2 years after their diagnosis.

Results

A total of 105 children (46 male, 43.8%) were included. The mean age at the time of diagnosis was 9.6 ± 4.1 years (range: 11 months-17.5 years). At the time of admission, 24 (22.9%), 29 (27.6%), and 52 (49.5%) patients had hyperglycemia, ketosis, and diabetic ketoacidosis, respectively. GAD-ab was positive in 55 children (52.4%). No background or sleep architecture abnormalities or focal slowing were present on the EEGs. Of the patients, 3 (2.9%) had focal epileptiform discharges. The mean GAD-ab levels of the remaining 102 patients were 7.48 ± 11.97 U/mL (range: 0.01-50.54) (p = 0.2). All 3 children with EEG abnormality had higher levels of GAD-ab (3.59 U/mL, 31.3 U/mL, and 7.09 U/mL, respectively). None of the patients developed epilepsy during the follow-up, although 1 patient experienced Guillain-Barré syndrome (GBS).

Conclusion

The prevalence of epileptiform discharges in the patients was similar to those of previous studies, in which healthy children were also included. No relationship was found between the epileptiform discharges and GAD-ab, and none of the patients manifested seizures during the first 2 years of follow-up of T1DM. These data support the findings of previous studies reporting that T1DM patients with confirmed electroencephalographic abnormalities do not have an increased risk of epilepsy. On the other hand, GBS might be considered as another autoimmune disease that may be associated with T1DM in children.

Glycaemic Imbalances in Seizures and Epilepsy of Paediatric Age: A Literature Review

Cerebral excitability and systemic metabolic balance are closely interconnected. Energy supply to neurons depends critically on glucose, whose fluctuations can promote immediate hyperexcitability resulting in acute symptomatic seizures. On the other hand, chronic disorders of sugar metabolism (e.g., diabetes mellitus) are often associated with long-term epilepsy. In this paper, we aim to review the existing knowledge on the association between acute and chronic glycaemic imbalances (hyper- and hypoglycaemia) with seizures and epilepsy, especially in the developing brain, focusing on clinical and instrumental features in order to optimize the care of children and adolescents and prevent the development of chronic neurological conditions in young patients.

Epilepsy, Immunity and Neuropsychiatric Disorders

Several studies have focused on the emerging role of immunity and inflammation in a wide range of neurological disorders. Autoimmune diseases involving central nervous system share well defined clinical features including epileptic seizures and additional neuropsychiatric symptoms, like cognitive and psychiatric disturbances. The growing evidence about the role of immunity in the pathophysiologic mechanisms underlying these conditions lead to the concept of autoimmune epilepsy. This relatively-new term has been introduced to highlight the etiological and prognostic implications of immunity in epileptogenesis. In this review, we aim to discuss the role of autoimmunity in epileptogenesis and its clinical, neurophysiological, neuroimaging and therapeutic implications. Moreover, we wish to address the close relationship between immunity and additional symptoms, particularly cognitive and psychiatric features, which deeply impact clinical outcomes in these patients. To assess these aspects, we first analyzed Rasmussen's encephalitis. Subsequently, we have covered autoimmune encephalitis, particularly those associated with autoantibodies against surface neuronal antigens, as these autoantibodies express a direct immune-mediated mechanism, different from those against intracellular antigens. Then, we discussed the connection between systemic immune disorders and neurological manifestations. This review aims to highlight the need to expand knowledge about the role of inflammation and autoimmunity in the pathophysiology of neurological disorders and the importance to early recognize these clinical entities. Indeed, early identification may result in faster recovery and a better prognosis.

Type 1 diabetes and epilepsy in childhood and adolescence: Do glutamic acid decarboxylase autoantibodies play a role? Data from the German/Austrian/Swiss/Luxembourgian DPV Registry

AIMS

We aimed to analyze the relationship between epilepsy and glutamic acid decarboxylase autoantibodies (GADA) in patients with type 1 diabetes mellitus (T1DM) and the impact of GADA on demographic, clinical, and metabolic data in T1DM patients with epilepsy.

METHODS

We searched for patients with T1DM ≤20 years and GADA measurements, and within this group for patients with epilepsy. We formed groups: T1DM + Epilepsy + GADA positive; T1DM + Epilepsy + GADA negative; T1DM + GADA positive; T1DM + GADA negative. We used logistic regression to analyze the relationship between epilepsy and GADA with odds ratio adjusted for sex, duration of diabetes (DOD), and age at diabetes onset (ADO). We used logistic regression with odds ratio adjusted for DOD and ADO onset using epilepsy as a dependent variable and GADA, HbA1c, ketoacidosis, severe hypoglycemia (SH), sex, celiac disease, and autoimmune thyroiditis as independent variables. We conducted regression analyses adjusted for sex, DOD, and ADO to analyze differences in clinical/metabolic parameters between the groups.

RESULTS

Epilepsy was not more frequent in GADA-positive patients (GPP). Logistic regression including all patients with GADA measurements showed that hypoglycemia with coma (HC) correlated with epilepsy when compared to no SH. We found no differences in clinical and metabolic data between GPP and GADA-negative patients (GNP) with epilepsy. SH occurred more often in GPP with epilepsy in comparison to GPP without epilepsy. GNP with epilepsy had a higher rate of HC than GPP without epilepsy.

CONCLUSION

We found no relationship between epilepsy and GADA. A relationship between T1DM and epilepsy might be explainable by SH.