The epidemiology of Helicobacter pylori infection and risk factors associated with its transmission are not well understood. Kazakhstan is country with two ethnic groups, Asian (Kazakhs) and Western (Russians), living under similar socioeconomic conditions. The aim of this study was to examine the seroepidemiologic pattern of H. pylori and hepatitis A among the same individuals from both ethnic groups, with emphasis on water source and household sanitation practices. This was a cross-sectional seroepidemiologic study conducted among unrelated healthy individuals in Kazakhstan. From May through August 1999, individuals between the ages of 10 and 60 years from Almaty, Kazakhstan, were invited to participate. Demographic information, socioeconomic factors, living conditions, and various aspects of the local household environment including access to water were collected. A clean water index (CWI) was created based on combined factors, consistency of boiling water before drinking, frequency of storing and reusing water, and frequency of bathing and showering. H. pylori and hepatitis A antibodies were assessed by enzyme-linked immunosorbent assay. Two hundred eighty-eight individuals between the ages of 10 and 60 years participated. The prevalence of H. pylori infection was almost identical among the two ethnic groups (Russians 79% and Kazakhs 80%). H. pylori infection was inversely correlated with the CWI (i.e., 56%, 79%, and 95% for high, middle, and low, respectively (P < .05). Drinking river water had highest risk of H. pylori infection (OR = 13.6, 95% CI = 1.8-102.4; P < .01, compared with tap water). Crowding showed no significant effect on H. pylori prevalence. Anti-HAV antibodies were found in 86% of the population, 90% among the Russians versus 82% among the Kazakhs (OR = 1.8, 95% CI = 1.1-3.8, P = .05). Although the two infections were highly correlated (P < .001), antibody to both infections were present simultaneously in only 74%. The prevalence of H. pylori infection in Kazakhstan is very high. The data suggest that transmission of H. pylori can be water borne, related to poor sanitary practices, or both. The high prevalence of antibodies to H. pylori and HAV among this population is a marker for poor sanitation and hygienic practices. Reducing the rate of H. pylori transmission will require improvements in overall sanitation including clean water, waste disposal, as well as in household hygienic practices.

Studies are difficult in areas lacking modern facilities due to the inability to reliably collect, store, and ship samples. Thus, we sought to evaluate the use of a dry plasma collection device for seroepidemiology studies. Plasma was obtained by fingerstick using a commercial dry plasma collection device (Chemcard Plasma Collection Device) and serum (venipuncture) from individuals in Kazakhstan. Plasma samples were air dried for 15 min and then stored desiccated in foil zip-lock pouches at 4 to 6°C and subsequently shipped to the United States by air at ambient temperature. Serum samples remained frozen at −20°C until assayed. Helicobacter pylori status was determined by enzyme-linked immunosorbent assay (HM-CAP EIA) for the dry plasma and the serum samples. The results were concordant in 250 of the 289 cases (86.5%). In 25 cases (8.6%), the dry plasma samples gave indeterminate results and could not be retested because only one sample was collected. Five serum samples were positive, and the corresponding dry plasma samples were negative; one serum sample was negative, and the corresponding plasma sample was positive. The relative sensitivity and specificity of the Chemcard samples to serum were 97.6 and 97.9%, respectively, excluding those with indeterminate results. Repeated freeze-thawing had no adverse effect on the accuracy of the test. We found the dry plasma collection device to provide an accurate and practical alternative to serum when venipuncture may be difficult or inconvenient and sample storage and handling present difficulties, especially for seroepidemiologic studies in rural areas or developing countries and where freeze-thawing may be unavoidable.

Background: Coronary artery bypass grafting (CABG) remains a standard revascularization strategy for patients with advanced coronary artery disease (CAD). However, a considerable proportion of patients experience recurrent ischemia requiring repeat revascularization. Residual platelet reactivity (RPR) and dyslipidemia are recognized as key factors contributing to graft failure and disease progression. Methods: This observational study was conducted at a tertiary cardiology center in Kazakhstan. A total of 195 post-CABG patients who underwent repeat coronary angiography between 2023 and 2024 recruitment period for recurrent ischemic symptoms within 6–36 months after surgery were included. Clinical characteristics, comorbidities, lipid profiles, and antiplatelet response were analyzed. RPR was measured using the VerifyNow P2Y12 assay when available. Dyslipidemia was defined according to the 2019 and 2021 European guidelines. Results: Elevated RPR was identified in 45% of patients (n = 90) despite dual antiplatelet therapy (p < 0.01). Poor lipid control was frequent among those who underwent repeat percutaneous coronary intervention (PCI), particularly elevated levels of low-density lipoprotein cholesterol (LDL-C) and total cholesterol (p < 0.05). Both elevated RPR and dyslipidemia were independently associated with native coronary disease progression and graft failure (RPR: OR = 2.8; 95% CI 1.4–5.6; p = 0.003; dyslipidemia: OR = 2.2; 95% CI 1.1–4.3; p = 0.02). The use of ezetimibe was independently associated with a significantly lower risk of repeat stenting (OR = 0.12; 95% CI 0.02–0.75; p = 0.023). Smokers were younger, had lower blood pressure, and less frequently presented with diabetes or chronic kidney disease, demonstrating a pattern consistent with the “smoker’s paradox.” Conclusions: Residual platelet reactivity and dyslipidemia are common and clinically relevant predictors of repeat revascularization after CABG. Optimization of antiplatelet and lipid-lowering therapy should be prioritized in secondary prevention for this high-risk population. These findings are particularly important in Kazakhstan, where post-CABG management strategies warrant further improvement.

Background: Optimal platelet inhibition is essential for minimizing both thrombotic and hemorrhagic complications in patients with coronary artery disease (CAD). Although high on-treatment platelet reactivity (HPR) has been consistently associated with adverse clinical outcomes, the relationship between platelet reactivity—measured as P2Y12 reaction units (PRU)—and cardiovascular mortality remains incompletely characterized. In particular, potential non-linear associations have not been adequately explored. Objective: We aimed to investigate the association between PRU and cardiovascular mortality in patients with CAD, with a specific focus on identifying potential non-linear relationships. Methods: We conducted a retrospective observational cohort study including 1000 patients with angiographically confirmed CAD treated at a tertiary cardiology center in Almaty, Kazakhstan, between 2024 and 2025. Platelet reactivity was assessed using the VerifyNow P2Y12 assay. Multivariable logistic regression models were used to identify independent predictors of cardiovascular mortality. To assess potential non-linear associations between PRU and mortality, restricted cubic spline regression was applied with predefined knot placement. Model performance was evaluated in terms of discrimination (C-statistic) and calibration (Hosmer-Lemeshow goodness-of-fit test). Results: In conventional linear regression models, PRU was not independently associated with cardiovascular mortality (odds ratio [OR] ~1.00; p > 0.05). However, spline-based analyses demonstrated a statistically significant non-linear (U-shaped) relationship between PRU and mortality risk (p for non-linearity = X). Both low and high PRU values were associated with increased mortality, whereas intermediate PRU levels corresponded to the lowest observed risk. Additional independent predictors of mortality included advanced age, diabetes mellitus, and elevated inflammatory markers. Conclusions: Our findings reveal a significant non-linear association between platelet reactivity and cardiovascular mortality in patients with CAD. Both insufficient and excessive platelet inhibition appear to confer increased risk, suggesting that optimal PRU targets may lie within an intermediate therapeutic range. These results support a paradigm shift toward more individualized antiplatelet therapy strategies guided by platelet function testing.

Aim. To investigate the prevalence and characteristics of polyvascular disease in the Eurasian region's population with one or more previously established locations of atherosclerotic arterial damage, and to evaluate the diagnostic importance of the ankle-brachial index (ABI) as a marker for polyvascular disease (PVD).Material and methods. A total of 1837 patients were included in the main branch of the KAMMA registry (patients with PVD), among which 91,6% had coronary artery disease (CAD) (n=1683). For further analysis, the group of patients with CAD was combined with 1222 patients included in the second branch of the registry — KAMMA-cardio, forming a patient population (n=2905), in which all patients had verified CAD. The mean age of patients was 66,0 [59,0; 72,0] years, with 60,3% being male. Peripheral arteries was assessed using ultrasound examination.Results. PVD was present in 95,6% of patients with coronary atherosclerosis: dual-region involvement was observed in 51,3% of patients, three-region involvement in 37,1%, four-region involvement in 3,4%, and five-region involvement in 2,0%. Stenoses of the common carotid artery were observed in 71% of patients, internal carotid artery — in 68%, lower limb artery — in 52%, and renal and mesenteric artery — in 8,3%. There were following diagnostic effectiveness of the ABI for detecting patients with lower limb artery stenosis was: sensitivity — 58,0%, specificity — 83,6%. The quality of antithrombotic and lipid-lowering therapy was insufficient.Conclusion. In the overwhelming majority (95,6%) of patients with CAD in the KAMMA registry, PVD was revealed, with nearly half of the patients having involvement in three or more arterial zones. In the patient population with CAD, there should be an active effort to identify patients with PVD, using at least the ABI determination and active modern antithrombotic and lipid-lowering therapy according to current clinical guidelines.

Background: Coronary artery bypass grafting (CABG) is a standard treatment for ad-vanced coronary artery disease (CAD). Despite its effectiveness, many patients devel-op recurrent ischemia requiring repeat revascularization. Residual platelet reactivity (RPR) and dyslipidemia are considered important contributors to graft failure and dis-ease progression. This study investigated the association of RPR and dyslipidemia with repeat revascularization in post-CABG patients. Methods: A observational cohort study was performed at a tertiary cardiology center in Kazakhstan. A total of 200 patients with prior CABG who underwent repeat coro-nary angiography between 2023 and 2024 for recurrent ischemic symptoms were in-cluded. Clinical data, comorbidities, lipid profiles, and antiplatelet response were ana-lyzed. RPR was measured with the VerifyNow P2Y12 assay where available. Dyslipidemia was defined according to current European guidelines, 2019/2021. Results: Elevated RPR was found in 45% (n = 90) of patients despite dual antiplatelet therapy. Poor lipid control, especially increased low-density lipoprotein cholesterol (LDL-C) and total cholesterol was common among patients undergoing repeat percu-taneous coronary intervention (PCI). Both RPR and dyslipidemia were independently associated with native coronary disease progression and graft failure. Conclusions: RPR and dyslipidemia are frequent and clinically relevant predictors of repeat revascularization after CABG. Optimizing antiplatelet and lipid-lowering ther-apy should be a priority in secondary prevention for this high-risk group. These results are particularly important in the Central Asian setting, where post-CABG management strategies require further improvement.