{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T05:54:52Z","timestamp":1781589292169,"version":"3.54.5"},"reference-count":26,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,14]],"date-time":"2026-06-14T00:00:00Z","timestamp":1781395200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Background: Post-COVID syndrome represents a significant medical and public health challenge, particularly among older adults and individuals with type 2 diabetes mellitus (T2DM), in whom disturbances in immune and metabolic homeostasis may contribute to the development and persistence of symptoms following SARS-CoV-2 infection. Objective: To investigate the clinical, immunological, and metabolic characteristics of post-COVID syndrome in older adults with T2DM. Methods: A cross-sectional comparative study was conducted involving 141 patients aged \u2265 60 years who were evaluated more than one year after SARS-CoV-2 infection. Clinical data, anthropometric measurements, complete blood count parameters, biochemical markers, glycated hemoglobin (HbA1c), and SARS-CoV-2-specific IgG antibodies were assessed. Statistical analyses were performed using nonparametric methods, while Pearson\u2019s \u03c72 test was applied for categorical variables. A p-value &lt; 0.05 was considered statistically significant. Results: Symptoms consistent with post-COVID syndrome one year after SARS-CoV-2 infection were identified in 53.2% of participants. No significant differences in anthropometric characteristics, hematological parameters, or most biochemical markers were observed between patients with and without post-COVID syndrome. Patients with T2DM exhibited higher fasting glucose, HbA1c, and SARS-CoV-2\u2013specific IgG antibody levels, reflecting underlying metabolic characteristics and differences in humoral immune responses during the late post-COVID period. Conclusions: Post-COVID syndrome symptoms were frequently observed among older adults at the time of assessment, more than one year after SARS-CoV-2 infection, despite normalization of most laboratory parameters. In patients with T2DM, higher glucose, HbA1c, and antibody levels likely reflect underlying metabolic characteristics rather than a direct effect of post-COVID syndrome. Further longitudinal studies are warranted to clarify the long-term clinical significance of the observed metabolic and immunological findings.<\/jats:p>","DOI":"10.3390\/v18060671","type":"journal-article","created":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T05:46:28Z","timestamp":1781588788000},"page":"671","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Clinical and Humoral Immune Features of Post-COVID Syndrome One Year After SARS-CoV-2 Infection in Elderly Patients with Type 2 Diabetes"],"prefix":"10.3390","volume":"18","author":[{"given":"Svetlana","family":"Bolshakova","sequence":"first","affiliation":[{"name":"Department of Endocrinology, Asfendiyarov Kazakh National Medical University, Almaty 050000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saule","family":"Altynbekova","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Asfendiyarov Kazakh National Medical University, Almaty 050000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhangentkhan","family":"Abylaiuly","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Asfendiyarov Kazakh National Medical University, Almaty 050000, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gulim","family":"Aldangarova","sequence":"additional","affiliation":[{"name":"Department of Postgraduate Education, Kazakh\u2013Russian Medical University, Almaty 050004, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,14]]},"reference":[{"key":"ref_1","unstructured":"National Institute for Health and Care Excellence (NICE) (2024, December 19). 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