POST-COVID-19 SYNDROME: INCIDENCE, BIOMARKERS, AND CLINICAL PATTERNS IN KAZAKHSTAN

Post-COVID syndrome (PCS) remains a significant challenge in modern medicine due to its diverse clinical manifestations and long-term impact on patients' health. Identifying risk factors and biomarkers associated with PCS can facilitate early diagnosis and improve patient management.

This study aimed to assess the prevalence, diagnostic markers and clinical characteristics of post-COVID syndrome (PCS) in the Abay region.

A retrospective-prospective cohort study was conducted among 639 individuals who had recovered from COVID-19. Participants were divided into two groups: those with PCS (n=300) and those without (n=339). Clinical and demographic data, laboratory biomarkers, and vaccination history were analyzed. Statistical analyses, including logistic regression, were applied to identify key risk factors and clinical subtypes of PCS.

The prevalence of PCS was 47%, with significant differences observed between groups regarding comorbid conditions, and laboratory biomarkers. PCS patients had a higher incidence of hypertension (47% vs. 23.5%, p=0.003) and diabetes mellitus (10.3% vs. 6.7%, p=0.032). Elevated alkaline phosphatase (ALP) levels were associated with PCS (p=0.004), whereas hematocrit (HCT) and immunoglobulin G (IgG) levels were lower in PCS patients. Cluster analysis identified four distinct clinical phenotypes, emphasizing the heterogeneity of PCS manifestations. Vaccination status showed a significant inverse correlation with PCS incidence (p=0.002), suggesting a protective effect of higher vaccine doses.

PCS presents with a broad spectrum of symptoms, necessitating a multidisciplinary approach for optimal patient management. Identified biomarkers, including ALP, HCT, and IgG, may serve as potential indicators for PCS diagnosis. Vaccination ap-pears to reduce PCS risk, highlighting the importance of immunization in mitigating long-term COVID-19 complications. These findings contribute to a better understanding of PCS pathophysiology and provide a foundation for future research and personalized treatment strategies.