TREM2 R47H variant and risk for Alzheimer's disease: assessment in a Greek population and updated meta-analysis.

INTRODUCTION: Rare coding variants in TREM2 and their association with the susceptibility towards Alzheimer's disease (AD) were recently studied in various ethnic groups with contradictory results. The T allele of the rs75932628 (p.R47H variant) has shown a positive risk association with AD in several studies; however, neither a study in Greece nor an updated meta-analysis have been conducted. OBJECTIVE: To assess the association between TREM2 rs75932628 and late-onset (sporadic) AD in a Greek population, and perform a meta-analysis of current data. MATERIALS AND METHODS: The rs75932628 was genotyped in a total of 327 patients with AD and 700 cognitively healthy controls. A systematic search and meta-analyses of studies presenting data regarding rs75932628 in AD cases and controls were also performed. RESULTS: Three patients vs. none of the controls were found to carry the heterozygous risk allele of the rs75932628, yielding a significant association (p = 0.032), in the Greek sample. In the meta-analysis, the overall odds ratio (OR) under a fixed-effects model was 2.98 (Confidence Interval (CI):2.52-3.53) showing a significant association of the rs75932628-T allele with AD in the overall dataset, based on data from 27 studies (26200 AD cases and 142084controls). Caucasian population-only studies (n = 16) revealed a similar OR of 2.93 (CI:2.45-3.51), whereas Asian population-only studies (n = 5) had a non-significant OR of 0.84 (CI:0.19-3.74). CONCLUSION: The rs75932628 was associated with AD in the Greek sample. Our meta-analysis, covering a total population of over 168,000 people, also showed a significant association of the allele with AD in Caucasian populations.

Medical Studies during the COVID-19 Pandemic: The Impact of Digital Learning on Medical Students' Burnout and Mental Health.

OBJECTIVES: The aim of this ecological study was to investigate what the impact of digital learning due to the COVID-19 pandemic was on the burnout and overall mental health (MH) of medical students. BACKGROUND: During the unprecedented era of the COVID-19 pandemic, the majority of countries worldwide adopted very strong measures. Universities closed their doors, and education continued through digital learning lectures. METHODS: An anonymous questionnaire was administered to all 189 eligible candidates before and during the COVID-19 pandemic. Mental health was assessed via the MH domain of the 36-item Short Form Health Survey (SF-36) and burnout with the Maslach Burnout Inventory-Student Survey (MBI-SS). RESULTS: The overall response rate was 81.5%. The overall burnout prevalence did not differ significantly between the two periods (pre-COVID-19 18.1% vs. COVID-19 18.2%). However, the burnout prevalence dropped significantly in year 4 (pre-COVID-19 40.7% vs. COVID-19 16.7%, p = 0.011), whereas it increased significantly in year 6 (pre-COVID-19 27.6% vs. COVID-19 50%, p = 0.01). When looking at each MBI-SS dimension separately, we found that emotional exhaustion decreased significantly in year 4 but increased in year 6, and cynicism increased in all years. The overall MH deteriorated significantly between the two periods (pre-COVID-19 58.8 ± 21.6 vs. COVID-19 48.3 ± 23, p < 0.001). CONCLUSIONS: Digital learning in medical studies carries significant risks. Not only does the MH deteriorate, but cynicism levels also increase. Emotional exhaustion was found to increase particularly in final year students, who struggle with the lack of clinical experience just before they start working as qualified junior doctors.

Assessment of TREM2 rs75932628 variant's association with Parkinson's disease in a Greek population and Meta-analysis of current data.

BACKGROUND: Α number of genetic variants are considered to confer susceptibility to Parkinson's disease (PD). Rs75392628 (R47H), a rare variant of TREM2 gene, has been linked to PD, although its role on PD remains conflicting. OBJECTIVE: Detection of a possible contribution of rs75392628 variant of TREM2 gene to PD risk. METHODS: A total of 358 PD patients and 358 healthy controls genotyped for rs75392628. In addition, a meta-analysis was performed by merging our results with those from previous studies. RESULTS: The rare variant of rs75932628 (47H) of TREM2 gene was not detected on cohort. Meta-analysis of a total of 9271 PD cases and 9777 controls across 14 independent PD data sets from 9 studies, including the present study, did not show any statistically significant effect of rs75392628 on PD risk (ORFE:1.54 95% CI:0.87-2.73. ORRE: 1.54, 95%CI: 0.71-3.32). CONCLUSIONS: Rs75392628 TREM2 variant is rather unlikely to be a major genetic risk contributor of PD.

Assessment of the reporting quality of double-blind RCTs for ischemic stroke based on the CONSORT statement.

BACKGROUND-PURPOSE: It is critical that Randomized Controlled Trials(RCTs) present complete and transparent reporting. The present study aims to determine the reporting quality of double-blind RCTs for medicinal interventions in patients with ischemic stroke, based on the 2010 CONSORT-statement. METHODOLOGY: MEDLINE was comprehensively searched. The CONSORT period was demarcated between 2000 and 2019, while compliance ≥75 was defined as good-adequate. Possible determinants were univariately and multivariately examined for associations. RESULTS: Overall, 197 articles were considered eligible, 143 published after and 54 before 2000. CONSORT compliance was 68.11% ± 11.56% (standard deviation) and 55.65% ± 11.57% respectively. Among retrieved articles 56/143(39.16%) and 1/54(1.85%) were rated as of good reporting quality correspondingly [p < .001, OR = 34.115, 95%CI = (4.586, 253.762)]. McNemar's test was indicative of consistency regarding the adequately/inadequately reported items before and after the 2010 CONSORT-revision (p = 1.00). Univariate analysis revealed two significant associations with the reporting quality: high impact factor(IF) [high vs. moderate; p = .007, OR = 3.521, 95%CI = (1.396, 8.879), high vs. low; p < .001, OR = 7.583, 95%CI = (3.063, 18.762), moderate vs. low; p = .078, OR = 2.154, 95%CI = (0.911, 5.093)] and sample size [p < .001, OR = 4.297, 95%CI = (2.081, 8.874)]. Publication period (p = .742) and funding (p = .280) were not significantly associated. Multivariate analysis attenuated the impact of sample size providing insignificant results, whereas the effect of high IF remained significant [moderate vs. high; p = .029, OR = 0.337, 95%CI = (0.127, 0.895), low vs. high; p = .012, OR = 0.199, 95%CI = (0.057, 0.699)]. An exploratory analysis demonstrated significant, weak to moderate, positive linear correlation between reporting quality and IF [Pearson's r = 0.418, p < .001]. CONCLUSIONS: Adherence to the CONSORT-statement needs to be further endorsed and incorporated in every journal's instructions-to-authors.

Prevalence and Management Challenges in Central Post-Stroke Neuropathic Pain: A Systematic Review and Meta-analysis.

INTRODUCTION: Central post-stroke pain (CPSP) is defined as the neuropathic pain that arises either acutely or in the chronic phase of a cerebrovascular event and is a result of central lesions of the somatosensory tract. The aim of this systematic review and meta-analysis was to establish the prevalence of CPSP, to describe its characteristics, and to discuss the associated management challenges. METHODS: After a systematic Medline search, we identified 69 papers eligible to be included. RESULTS: The pooled prevalence of CPSP in patients with stroke at any location was 11% (95% CI 7-18%), which can increase to more than 50% in the subgroups of patients with medullary or thalamic strokes. CPSP onset coincides with stroke occurrence in 26% of patients (95% CI 18-35%); CPSP manifests within a month since symptom onset in 31% of patients (95% CI 22-42%), and occurs between the first month and the first year in 41% of patients (95% CI 33.9-49.0%). CPSP develops more than 12 months after stroke onset in 5% of patients (95% CI 3-8%). CONCLUSIONS: Clinicians should look for any evidence of central neuropathic pain for at least 12 months after stroke. Both pharmacological and non-pharmacological interventions can be used for the management of CPSP. Lamotrigine has the strongest evidence (Level II of evidence, derived from small randomized controlled trials) for being effective in the management of CPSP. Future research should focus on well-designed trials of pharmacological and non-pharmacological interventions aiming to relief CPSP, which is a very common but often neglected pain syndrome.

Corrigendum: Precision Medicine and Global Health: The Good, the Bad, and the Ugly.

[This corrects the article on p. 67 in vol. 5, PMID: 29594124.].

Large-scale assessment of polyglutamine repeat expansions in Parkinson disease.

OBJECTIVES: We aim to clarify the pathogenic role of intermediate size repeat expansions of SCA2, SCA3, SCA6, and SCA17 as risk factors for idiopathic Parkinson disease (PD). METHODS: We invited researchers from the Genetic Epidemiology of Parkinson's Disease Consortium to participate in the study. There were 12,346 cases and 8,164 controls genotyped, for a total of 4 repeats within the SCA2, SCA3, SCA6, and SCA17 genes. Fixed- and random-effects models were used to estimate the summary risk estimates for the genes. We investigated between-study heterogeneity and heterogeneity between different ethnic populations. RESULTS: We did not observe any definite pathogenic repeat expansions for SCA2, SCA3, SCA6, and SCA17 genes in patients with idiopathic PD from Caucasian and Asian populations. Furthermore, overall analysis did not reveal any significant association between intermediate repeats and PD. The effect estimates (odds ratio) ranged from 0.93 to 1.01 in the overall cohort for the SCA2, SCA3, SCA6, and SCA17 loci. CONCLUSIONS: Our study did not support a major role for definite pathogenic repeat expansions in SCA2, SCA3, SCA6, and SCA17 genes for idiopathic PD. Thus, results of this large study do not support diagnostic screening of SCA2, SCA3, SCA6, and SCA17 gene repeats in the common idiopathic form of PD. Likewise, this largest multicentered study performed to date excludes the role of intermediate repeats of these genes as a risk factor for PD.

Assessment of the relative effectiveness and tolerability of treatments of type 2 diabetes mellitus: a network meta-analysis.

PURPOSE: The relative effectiveness and tolerability of treatments for type 2 diabetes mellitus (T2DM) is not well understood because few randomized, controlled trials (RCTs) have compared these treatments directly. The purpose of the present study was to evaluate the relative effectiveness and tolerability of treatments of T2DM. METHODS: We performed a network meta-analysis of available RCTs with pharmacologic interventions in T2DM and compared antidiabetic drugs and combination regimens with metformin (the reference drug). Glycemic control (proportion achieving HbA1c goal) and tolerability (risk of hypoglycemia) were the primary outcomes of interest. Direct and indirect relative effects (unadjusted) were expressed as odds ratios and 95% CIs. FINDINGS: Eight treatments (glucagon-like peptide-1 [GLP-1] agonists plus metformin, sulfonylureas plus metformin, dipeptidyl peptidase-4 [DPP-4] inhibitors] plus metformin, colesevelan plus metformin, thiazolidinediones plus metformin, meglitinides plus metformin, α-glucosidase inhibitor plus metformin, and rosiglitazone monotherapy) outperformed metformin (direct effects). Triple combinations of GLP-1, thiazolinedione, insulin, metiglinide, or sulfonylureas added to a metformin backbone improved glycemic control (indirect effects). Higher risk of hypoglycemia was noted for sulfonylureas, α-glycosidases, and metiglinides when added to metformin (direct effects). Across indirect effects, only 17% of comparisons yielded less risk of hypoglycemia (70% were worse and 13% were comparable). IMPLICATIONS: Our results point out the relative superiority of 2- and 3-drug combination regimens over metformin and summarize treatment effects and tolerability in a comprehensive manner, which adds to our knowledge regarding T2DM treatment options.

Assessment of Parkinson's disease risk loci in Greece.

Genome-wide association studies (GWAS) have been shown to be a powerful approach to identify risk loci for neurodegenerative diseases. Recent GWAS in Parkinson's disease (PD) have been successful in identifying numerous risk variants pointing to novel pathways potentially implicated in the pathogenesis of PD. Contributing to these GWAS efforts, we performed genotyping of previously identified risk alleles in PD patients and control subjects from Greece. We showed that previously published risk profiles for Northern European and American populations are also applicable to the Greek population. In addition, although our study was largely underpowered to detect individual associations, we replicated 5 of 32 previously published risk variants with nominal p values <0.05. Genome-wide complex trait analysis revealed that known risk loci explain disease risk in 1.27% of Greek PD patients. Collectively, these results indicate that there is likely a substantial genetic component to PD in Greece, similarly to other worldwide populations, that remains to be discovered.

Epidemiology, impact, and treatment options of restless legs syndrome in end-stage renal disease patients: an evidence-based review.

Restless legs syndrome (RLS) (or Willis-Ekbom disease) is a neurological disorder with high prevalence among the end-stage renal disease population. This is one of the most predominant types of secondary RLS, and it is called uremic RLS. Despite the fact that uremic RLS has been less studied compared to idiopathic RLS, recent studies now shed light in many aspects of the syndrome including clinical characteristics, impact, epidemiology, and treatment options. The current review discusses the above topics with special emphasis given on the management of uremic RLS, including the management of symptoms that often appear during a hemodialysis session. Uremic RLS symptoms may be ameliorated by using pharmacological and nonpharmacological treatments. Evidence so far shows that both approaches may be effective in terms of reducing the RLS symptom's severity; nevertheless, more research is needed on the efficiency of treatments for uremic RLS.