Yuliya Semenova

Background: Clinical and survival data on pulmonary arterial hypertension (PAH) from Central Asia remain limited. This study aimed to characterize the clinical profile, survival outcomes, and prognostic value of baseline COMPERA 2.0 risk stratification in patients with PAH in Kazakhstan. Methods: This retrospective observational study included 206 adult patients with right heart catheterization-confirmed PAH hospitalized at the largest pulmonary hypertension referral center in Kazakhstan between 2020 and 2024. Patients were categorized into idiopathic PAH (IPAH), congenital heart disease-associated PAH (CHD-PAH), and other PAH subgroups. Kaplan–Meier survival was assessed from the index hospitalization, and Cox regression used patients with complete data for the variables included in each model. The multivariable model included 182 patients (39 deaths). Baseline risk stratification was assessed retrospectively using the COMPERA 2.0 four-strata model. Results: Etiological groups comprised 121 (58.7%) with IPAH, 73 (35.4%) with CHD-PAH, and 12 (5.8%) with other forms of PAH. The mean age was 39.5 ± 13.7 years, and 80.6% were female. At baseline, 62.6% were classified as WHO functional class III–IV. Overall survival did not differ significantly according to PAH etiology (log-rank p = 0.407). Baseline COMPERA 2.0 four-strata risk stratification differentiated survival (log-rank p < 0.001). In multivariable Cox regression analysis, baseline COMPERA 2.0 four-strata risk category remained associated with mortality (overall p = 0.006), with an adjusted HR of 4.67 (95% CI 1.22–17.86) for high-risk versus low-risk patients. Higher tricuspid annular plane systolic excursion (TAPSE) was independently associated with lower mortality hazard (HR 0.89 per mm increase, 95% CI 0.8–0.99; p = 0.026). Conclusions: In this hospitalized, single-center cohort from Kazakhstan, patients were predominantly young women with advanced functional impairment at baseline. Baseline COMPERA 2.0 four-strata risk assessment and lower TAPSE were associated with mortality after multivariable adjustment. These findings support multidimensional risk assessment in patients with PAH and highlight the need for prospective regional PAH registries.

Background: Tuberculosis (TB) mortality remains an important indicator of disease burden, health system performance, and progress toward global TB control targets. This study aimed to assess long-term trends in TB mortality in Kazakhstan from 1998 to 2024 and to examine regional differences and population-level factors associated with mortality. Methods: A retrospective descriptive study with a documentary analysis component was conducted using official national statistical data. TB mortality rates were analyzed at the national and regional levels, and associations with health system indicators, clinical TB characteristics, and population health factors were assessed using correlation and regression analyses. Results: TB mortality in Kazakhstan declined from 38.4 per 100,000 population in 1998 to 1.0 per 100,000 in 2024, corresponding to an overall reduction of approximately 97.4%. Despite this marked decline, regional differences persisted. The steepest reductions were observed in Mangystau (AAPC −16.38%), Aktobe (−15.65%), and Pavlodar (−15.28%) regions. By 2024, mortality was below 3 per 100,000 nationwide, although East Kazakhstan, Karagandy, West Kazakhstan, and North Kazakhstan retained comparatively higher rates. TB mortality was negatively associated with the number of physicians and positively associated with hospital service utilization indicators, the proportion of fibrocavitary TB among newly registered cases, and alcohol dependence. Conclusions: The long-term decline in TB mortality coincided with major national TB control reforms, including the expansion of DOTS/DOTS-Plus, wider access to rapid molecular diagnostics, and the introduction of all-oral treatment for drug-resistant TB. Further efforts are warranted to reduce persistent regional disparities and sustain progress in TB mortality reduction.

Background: Kazakhstan is among the most highly endemic countries for hepatic echinococcosis worldwide, yet no study systematically characterised the national hepatobiliary surgical burden of cystic (CE) and alveolar (AE) echinococcosis using administrative health data. Methods: National operative data from the Guaranteed Volume of Free Medical Care (GOBMP) and Compulsory Social Health Insurance (OSHI) Systems (1 January 2023–31 December 2025) were combined with institutional case series from the National Research Oncology Center (NROC), Astana (2021–2025). Cases were identified using ICD-10 diagnosis codes and ICD-9-CM procedure codes. Regional and species-specific differences in surgical approach were assessed using Pearson’s chi-square test; continuous variables were compared using the Mann–Whitney U test. Results: A total of 143 hepatic echinococcosis surgeries were performed nationally over the three-year period, with a 12.8% increase in annual volume (47 in 2023, 43 in 2024, 53 in 2025), though this year-to-year variation was not statistically significant (χ² = 1.06, df = 2, p = 0.59). CE accounted for 74.8% of cases (n = 107), AE for 18.9% (n = 27), and unspecified hepatic echinococcosis for 6.3% (n = 9); the proportion of AE rose from 17.0% in 2023 to 26.4% in 2025. Astana performed 46.2% of all operations nationally, with its share increasing from 34.0% to 58.5% over the study period; together with Almaty, it accounted for 92.6% of all AE cases. Partial hepatic resection was the predominant procedure overall (81.1%), while AE was managed exclusively by resectional or lobar procedures (χ² = 15.37, p = 0.004), with no percutaneous approaches used. In the NROC case series (n = 63), AE patients were older (median 43.5 vs. 33 years, p = 0.036) and had longer postoperative hospital stays (median 12 vs. 10 days, p = 0.015) than CE patients. Conclusions: Surgical management of hepatic echinococcosis in Kazakhstan is increasingly centralised in Astana and Almaty, with AE consistently requiring more extensive resectional surgery and greater healthcare resource use than CE. These findings support the development of a national echinococcosis registry and formal referral pathways to guide resource allocation and surgical planning.

Background: Static cold storage (SCS) remains the conventional standard for liver graft preservation; however, ischemia–reperfusion injury during storage may contribute to graft dysfunction, particularly with extended criteria and marginal donors. Machine perfusion (MP) has emerged as a promising alternative, yet existing systematic reviews are limited by their focus on individual perfusion modalities or selected donor populations. We performed a comprehensive systematic review and meta-analysis with pre-specified modality-specific subgroup analyses comparing all MP strategies with SCS in adult liver transplantation. Methods: This study was conducted in accordance with PRISMA 2020 guidelines and registered in PROSPERO (CRD420261355605). MEDLINE, Embase, and PubMed were systematically searched for comparative studies published between 2015 and 2025. Primary outcomes were early allograft dysfunction (EAD), primary non-function (PNF), and 1-year graft survival. Secondary outcomes included biliary complications, hepatic artery thrombosis (HAT), and postoperative transaminase levels. Pre-specified subgroup analyses were performed according to perfusion modality (NMP versus HMP/HOPE). Results: A total of 1448 records were identified. After removal of 309 duplicates and screening, 21 studies comprising 3665 patients were included. Compared with SCS, MP was associated with a significantly lower risk of EAD (RR 0.67, 95% CI 0.48–0.94; p = 0.020), PNF (RR 0.31, 95% CI 0.11–0.84; p = 0.020), and graft loss at one year (RR 0.54, 95% CI 0.36–0.81; p = 0.003; I² = 0%). Subgroup analysis demonstrated that reductions in EAD and PNF were driven by HMP/HOPE strategies (EAD: RR 0.66, 95% CI 0.45–0.98; PNF: RR 0.23, 95% CI 0.07–0.79), whereas NMP did not achieve statistical significance for these endpoints. No significant differences were observed in biliary complications or HAT. Conclusions: Machine perfusion is associated with improved early graft function, reduced primary non-function, and superior 1-year graft survival compared with static cold storage. The benefit for early graft outcomes is driven by hypothermic strategies. These findings provide modality-specific evidence to guide preservation strategy selection in clinical practice.

Taurine, a sulfur-containing amino acid, has been shown to exhibit various biological activities, including antioxidant, anti-inflammatory, and anti-cancer properties. This review provides a comprehensive summary of current preclinical and clinical evidence regarding taurine’s role in cancer prevention and treatment. in vitro studies have demonstrated that taurine induces apoptosis, suppresses cell proliferation, and inhibits angiogenesis and metastasis. Animal studies support these findings, indicating that taurine supplementation has anti-cancer effects in vivo. Epidemiological studies have reported mixed results on the association between taurine intake and cancer risk, while clinical studies on taurine supplementation have reported promising outcomes in cancer patients. Limitations of current studies include small sample sizes, lack of standardization in study design, and inconsistent dosages of taurine supplementation. Future research directions involve elucidating the underlying mechanisms of action and conducting rigorously designed clinical trials with larger cohorts. In conclusion, the available evidence suggests that taurine may have potential as a complementary or alternative therapy for cancer; however, further research is needed to establish its safety and efficacy.

Background/Objectives: Few studies have examined how health policies may influence antibiotic consumption at a global level, particularly with respect to the World Health Organization (WHO) “Access” group antibiotics. Our present study aims to address this gap by investigating how health policies affect the availability of “Access” antibiotics in a middle-income country of Kazakhstan. Methods: This study employed a mixed-methods approach: the quantitative component consisted of a time series analysis of “Access” antibiotic consumption within the period 2017–2024; the qualitative component involved an analysis of health policies centered on regulating the availability of “Access” antibiotics and their prescription at the primary care level. Results: A declining trend in the consumption of “Access” antibiotics was observed during the period from 2017 to 2023; however, in 2024 there was a rebound in consumption. The consumption of “Access” antibiotics did not reach the 60% threshold recommended by the WHO. A total of 50 “Access” antibiotics were found to be unavailable in the country, of which 9 are included in the WHO Essential Medicines List. Analysis of health policies highlighted that the registration of medicines may only be initiated by the manufacturer or its representative. Furthermore, analysis of national standards of care for common infections in primary care indicated a preference for prescribing “Watch” antibiotics, or prescribing antibiotics where their use would not be indicated. Conclusions: A coordinated policy response is needed in Kazakhstan to strengthen antimicrobial stewardship, including improving the availability of “Access” antibiotics, decentralization, revising national standards of care, and addressing regulatory barriers to medicine registration.

This study explores the relationship between vitamin E and Alzheimer's disease (AD), a neurodegenerative disorder characterized by cognitive decline, memory loss, and language impairment. Vitamin E is a fat-soluble antioxidant crucial in protecting cells from oxidative damage. The biochemistry and bioavailability of vitamin E are discussed, including its absorption, transport, and storage in the body. The section on interactions between vitamin E and other nutrients and herbals highlights how combining vitamin E supplements with other supplements or medications can affect its absorption, metabolism, and effectiveness. This study also discusses the potential therapeutic effects of vitamin E on AD, including its ability to reduce oxidative stress and inflammation, which are thought to play a role in the pathophysiology of AD. It explores the synergistic effects of vitamin E with pharmaceuticals and potential side effects, and covers the use of vitamin E in combination with other drugs for AD treatment, such as cholinesterase inhibitors and memantine, as well as the possible adverse effects of vitamin E supplementation. Overall, this study highlights the importance of vitamin E in preventing and managing AD and underscores the need for further research in this area.

Breast cancer (BC) is the most common cancer in Kazakhstan, and a population-based breast cancer screening program was introduced in 2008, initially targeting women aged 50–60 years. It was subsequently expanded in 2018 to include women aged 40–70 years. This study evaluates the national BC screening program from its introduction in 2008 onward, focusing on program outputs, outcomes, and associated expenditures. Several administrative datasets and official sources were analyzed, including the legislative acts database, analytical reports on cancer screening programs, and cancer reporting forms. Trends in key indicators were summarized using the average annual percent change (AAPC). From the program’s inception, the absolute number of women screened increased steadily, with an AAPC of 6.23%. In contrast, the proportion of eligible women covered by screening declined over time, particularly following the expansion of the target age groups in 2018. Stage I BC detected through screening accounted for only about 50% of all stage I BC cases diagnosed nationwide, while the contribution of screening to stage II cancers was below 30%. Neither the introduction nor the subsequent expansion of the BC screening program was associated with statistically significant immediate or trend changes in national BC incidence or mortality rates. These findings may inform evidence-based discussions on potential refinements to BC screening policy and practice in Kazakhstan.

Background: Male infertility (MI) has become an important public health concern in Central Asia (CA), where declining fertility coincides with limited integration of male reproductive health into national strategies. This study analyzed trends in the prevalence and burden of MI in CA countries and assessed associations with selected modifiable behavioral risk factors. Methods: A longitudinal analysis of Global Burden of Disease (GBD) 2023 data was conducted to estimate the age-standardized prevalence and incidence of MI among men aged 15–49 years in five CA countries from 1990 to 2023. Trends were examined, and fixed-effects panel regression models were applied to evaluate associations between MI burden and alcohol use, drug use, and sexually transmitted infections (excluding HIV). Results: From 1991 to 2023, the age-standardized prevalence increased in four CA countries, whereas Tajikistan showed a decline; the incidence rose across all countries. The peak incidence was most commonly observed at ages 35–39 years, although Tajikistan shifted toward a younger age group, and regression analyses revealed heterogeneous country-specific associations with sociobehavioral risk factors. Conclusions: MI represents a significant demographic and public health challenge in CA, highlighting the need to strengthen surveillance, standardize diagnostics, improve access to care, and integrate male reproductive health into national prevention strategies.