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Background and Purpose: The International Movement Disorder Society revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) is widely used in the assessment of the severity of Parkinson’s disease (PD). This study aimed to validate the Kazakh version of the MDS-UPDRS, explore its dimensionality, and compare it to the original English version. Methods: The validation was conducted in three phases: first, the English version of the MDS-UPDRS was translated into Kazakh and thereafter back-translated into English by two independent teams; second, the Kazakh version underwent a cognitive pretesting; third, the Kazakh version was tested in 360 native Kazakh-speaking PD patients. Both confirmatory and exploratory factor analyses were performed to validate the scale. We calculated the comparative fit index (CFI) for confirmatory factor analysis and used unweighted least squares for exploratory factor analysis. Results: The CFI was higher than 0.90 for all parts of the scale, thereby meeting the pre-set threshold for the official designation of a validated translation. Exploratory factor analysis also showed that the Kazakh MDS-UPDRS has the analogous factors structure in each part as the English version. Conclusions: The Kazakh MDS-UPDRS had a consistent overall structure as the English MDS-UPDRS, and it was designated as the official Kazakh MDS-UPDRS, which can reliably be used in the Kazakh-speaking populations. Presently, Kazakhstan stands as the sole country in both Central Asia and Transcaucasia with an MDS-approved translated version of the MDS-UPDRS. We expect that other Central Asian and Transcaucasian countries will embark on the MDS Translation Program for MDS-UPDRS in the near future.

ABSTRACT Background Knowledge of the genetic background of many human diseases is currently lacking from genetically undiscovered regions, including Central Asia. Kazakhstan is the first Central Asian country where the genetic studies of Parkinson's disease (PD) have been emerging since it had become a member of the International Parkinson Disease Genomics Consortium. Here we report on the results of whole‐exome sequencing (WES) in 50 young‐onset PD (YOPD) cases from Kazakhstan. Methodology WES was performed on 50 unrelated individuals with YOPD from Kazakhstan. Exome data were screened for novel/ultra‐rare deleterious variants in known and candidate PD genes. Copy number variants and small indels were also called. Results Only three cases (6%) were found to be positive for known PD genes including two unrelated familial PD cases with LRRK2 p.(Arg1441Cys) and one case with a homozygous pathogenic PRKN p.(Arg84Trp) variant. Four cases had novel and ultra‐rare variants of uncertain significance in LRRK2, DNAJC13, and VPS35. Novel deleterious variants were found in candidate Mendelian PD genes including CSMD1, TNR, EIF4G1, and ATP13A3. Eight cases harbored the East Asian‐specific LRRK2 p.(Ala419Val) variant. Conclusions The low diagnostic yield in our study might imply that a significant proportion of YOPD cases in Central Asia remains unresolved. Therefore, a better understanding of the genetic architecture of PD among populations of Central Asian ancestry and the pathogenicity of numerous rare variants should be further investigated. WES is a valuable technique for large‐scale YOPD genetic studies in Central Asia.

Background. LRRK2 mutations have emerged as the most prevalent and potentially treatable determinants of Parkinson’s disease (PD). Peculiar geographic distribution of these mutations has triggered an interest in genotyping PD cohorts of different ethnic backgrounds for LRRK. Objective. Here, we report on the results of LRRK2 screening in the first Central Asian PD cohort. Methods. 246 PD patients were consecutively recruited by movement disorder specialists from four medical centers in Kazakhstan, and clinicodemographic data and genomic DNA from blood were systematically obtained and shipped to the Institute of Neurology University College London together with DNAs from 200 healthy controls. The cohort was genotyped for five LRRK2 mutations (p.Gly2019Ser, p.Arg1441His, p.Tyr1699Cys, p.Ile2020Thr, and p.Asn1437His) and three East Asian disease-associated variants (p.Gly2385Arg, p.Ala419Val, and p.Arg1628Pro) via Kompetitive allele-specific polymerase chain reaction assay analysis. Results. None of the study subjects carried LRRK2 mutations, whereas the following Asian variants were found with insignificant odds ratios (OR): p.Gly2385Arg (1.2%, minor allele frequency (MAF) 0.007, OR 1.25, p=0.8), p.Ala419Val (3.7%, MAF 0.02, OR 1.5, p=0.4), and p.Arg1628Pro was found only in 1% of controls. p.Gly2385Arg was positive in a big family with PD and tremor, although with incomplete segregation. One early-onset PD subject was homozygous for p.Ala419Val who developed fast progression and severe dyskinesias. p.Ala419Val was associated with early-onset PD. Conclusions. We showed that East Asian LRRK variants could be found in Central Asian populations but their pathogenicity remains to be elucidated in larger PD cohorts.

Purpose: to estimate efficiency of pathogenetic therapy of diabetic polyneuropathy with including of benfotiaminby means of an electroneuromyography. Materials: assessment of efficiency of pathogenetic therapy of diabetic polyneuropathy with including of benfotiaminat patients with various experience of a diabetes mellitus 2 types was carried out. The research included three groups of patients with an experience of diabetes 2 type – 1-3 years (1 group), 3-7 years (the 2nd group), 7-10 years (the 3rd group). The conduction research on nerves of the lower extremities by an electroneuromyography method was the main criterion of efficiency (primary final point). Results: according to ENMG-control statistically significant improvement of conduction on peripheric nerves against the background of therapy by benfotiamin within 12 weeks was shown. More faster improvement of conduction was reached in groups with a smaller experience of a diabetes mellitus (up to 7 years) and at the patients who were earlier receiving courses of pathogenetic therapy. Conclusions: Including of benfotiamin in a complex of therapy of diabetic polyneuropathy allows to achieve reliable improvement of a condition of peripheric nerves from patients with various experience of a diabetes mellitus 2 types.

Our understanding of Parkinson’s disease (PD) has significantly accelerated over the last few years, but predominant advances have been made in developed, Western countries. Little is known about PD in the Central Asian (CA) and Transcaucasian (TC) countries. Here, we review the clinical characteristics, treatments used, epidemiology, and genetics of PD in CA and TC countries via a methodological search in MEDLINE, EMBASE, Scopus, Web of Science, and Google Scholar databases. For the acquisition of PD care-related data, the search was extended to the local web resources. Our findings showed that PD prevalence in the region is averaging 62 per 100,000 population. The mean age of onset is 56.4 ± 2.8 in females and 63.3 ± 3.5 in males. Large-scale national studies on PD prevalence from the region are currently lacking. A limited number of genetic studies with small cohorts and inconclusive results were identified. The G2019S LRRK2 mutation, the commonest mutation in PD worldwide, was found in 5.7% of patients with idiopathic PD and 17.6% of familial cases in 153 Uzbek patients. Our review highlighted systematic deficiencies in PD health care in the region including lacks of neurologists specializing in PD, delays in PD diagnosis, absence of specialized PD nurses and PD rehab services, limited access to PD medications and surgery, and the unavailability of PD infusion therapies. Overall, this article demonstrated the paucity of data on this common neurological disorder in CA and TC countries and identified a number of healthcare areas that require an urgent consideration. We conclude that well-designed large-scale epidemiological, genetic, and clinical studies are desperately needed in this region. Healthcare professionals, local and national institutions, and stakeholders must come together to address deficiencies in PD healthcare systems in CA and TC countries.