ABSTRACT
Background: Cancer patients are at high risk of severe COVID infection and recommended at least three doses of SARS-CoV2 mRNA vaccines. Various anti-neoplastic treatments may affect long-term vaccine immunogenicity. Methods: Patients with solid or haematological cancer were recruited from two Singapore hospitals between July 2021 and March 2022. GenScript cPASS surrogate virus neutralisation assays measured antibody responses, which were correlated with clinical outcomes obtained from medical records and national mandatory-reporting databases. Results: In total, 273 patients were recruited (40 with haematological malignancies and the rest solid tumours). Two-hundred and four patients (74.7%) were receiving active cancer therapy: 98 (35.9%) receiving systemic chemotherapy and the rest targeted or immunotherapy. All patients were seronegative at baseline. After receiving one, two and three doses of SARS-CoV-2-mRNA vaccination, seroconversion rate was 35.2%, 79.4% and 92.4% respectively. After three doses, patients on active treatment for haematological malignancies had lower antibodies (57.3%±46.2) as compared to patients on immunotherapy (94.1%±9.56, p<0.05) and chemotherapy (92.8%±18.1, p<0.05). SARS-CoV-2 infection was reported in 77 (28.2%) patients of which 18 were severe. Conclusion: This study demonstrates high immunogenicity of three doses of vaccines and protection against severe infection in cancer patients.
ABSTRACT
PURPOSE: Serum electrolyte imbalances are highly prevalent in COVID-19 patients. However, their associations with COVID-19 outcomes are inconsistent, and of unknown prognostic value. We aim to systematically clarify the associations and prognostic accuracy of electrolyte imbalances (sodium, calcium, potassium, magnesium, chloride and phosphate) in predicting poor COVID-19 clinical outcome. METHODS: PubMed, Embase and Cochrane Library were searched. Odds of poor clinical outcome (a composite of mortality, intensive-care unit (ICU) admission, need for respiratory support and acute respiratory distress syndrome) were pooled using mixed-effects models. The associated prognostic sensitivity, positive and negative likelihood ratios (LR + , LR-) and predictive values (PPV, NPV; assuming 25% pre-test probability), and area under the curve (AUC) were computed. RESULTS: We included 28 observational studies from 953 records with low to moderate risk-of-bias. Hyponatremia (OR = 2.08, 95% CI = 1.48-2.94, I2 = 93%, N = 8), hypernatremia (OR = 4.32, 95% CI = 3.17-5.88, I2 = 45%, N = 7) and hypocalcemia (OR = 3.31, 95% CI = 2.24-4.88, I2 = 25%, N = 6) were associated with poor COVID-19 outcome. These associations remained significant on adjustment for covariates such as demographics and comorbidities. Hypernatremia was 97% specific in predicting poor outcome (LR + 4.0, PPV = 55%, AUC = 0.80) despite no differences in CRP and IL-6 levels between hypernatremic and normonatremic patients. Hypocalcemia was 76% sensitive in predicting poor outcome (LR- 0.44, NPV = 87%, AUC = 0.71). Overall quality of evidence ranged from very low to moderate. CONCLUSION: Hyponatremia, hypernatremia and hypocalcemia are associated with poor COVID-19 clinical outcome. Hypernatremia is 97% specific for a poor outcome, and the association is independent of inflammatory marker levels. Further studies should evaluate if correcting these imbalances help improve clinical outcome.