Predictors of fatal neurological complications among admitted COVID-19 patients with their implication in outcome: A Case Control study.

BACKGROUND: COVID-19 is known to be associated to potentially fatal neurological complications; therefore, it is essential to understand the risk factors for its development and the impact they have on the outcome of COVID-19 patients. AIMS: To determine the risk factors for developing fatal neurological complications and their outcome in hospitalized COVID-19 patients. MATERIAL AND METHODS: Case control study based on hospitalized patients was conducted from July 15th 2021 to December 15th 2021. Cases and controls were COVID-19 confirmed patients with and without severe neurological manifestations. Age, comorbid conditions, vaccination status, Blood Sugar Random (BSR), D-dimers levels, anticoagulation type and dosage were taken as predictors (exposure variables) for developing neurological complications. In the case-only (subgroup) analysis, 28-day mortality were analyzed using the same predictors including admission hypoxemia. Chi square test and regression model were built to calculate OR with 95%CI. RESULTS: Among 383 patients (median age, 56 years [IQR, 24-110]; 49.9% men); 95 had neurological complications (cases) and 288 did not (controls). Development of neurological complications among COVID-19 related hospitalizations was significantly associated with old age >71 yrs. (cases, 23.2%; controls, 13.5%; OR, 3.31; 95% CI, 1.28-8.55), presence of diabetes mellitus (37.9% vs. 24%; OR, 1.9; 95% CI, 1.2-3.1), admission hyperglycemia (BSR 351-600 mg/dl), (29.5% vs. 7.6%; OR, 3.11; 95%CI, 1.54-6.33), raised D-dimer levels 5000-10,000 ng/ml (41% vs. 11.8%; OR, 5.2; 95% CI, 3.02-8.9), prophylactic dose anticoagulation (43.2% vs. 28.1%; OR, 1.9; 95%CI, 1.2-3.1), and unvaccinated status of COVID-19 patients (90.5% vs. 75.6%; OR, 3.01; 95% CI, 1.44-6.25). Neurological complications with COVID-19 were associated with increased likelihood of death or invasive mechanical ventilation by day 28 (86.3% vs. 45.1%; OR, 7.66; 95% CI, 4.08-14.4). In case-only analysis (median age, 56 years [IQR, 27,110]; 50.5% women), 67 (70.5%) had CVE, 21 (22.1%) had Encephalitis, and 7 (7.4%) had GBS as neurological manifestations. 28-day mortality among these patients was strongly associated with a lower likelihood of vaccination. (6.1% cases vs. 30.8% controls; OR, .146; 95%CI, .033- .64), being younger 17-45 yrs. (12.2% vs. 46.2%; OR, .162; 95%CI, .045-.58), having no comorbid condition (19.5% vs. 61.5%; OR, .151; 95%CI, .044- .525), having cerebrovascular events and GBS as type of neurological manifestation (76.8% vs.30.8%; OR, 7.46; 95%CI, 2.06-26.96), (2.4% vs. 38.4%; OR, .04; 95%CI, .007- 0.24) respectively, and presence of hypoxemia at admission (91.5% vs. 15.4%; OR, 58.92; 95%CI, 10.83-320.67). CONCLUSION: Old age, presence of Diabetes Mellitus, unvaccinated status of patients, high BSR at admission, high D-dimers, and prophylactic dose anticoagulation were identifies as increased risk factors for developing serious neurological complications among COVID-19 patients. Neurological problems in COVID-19 patients raised death risk 7.6-fold. The most common neurological complication was cerebrovascular events, followed by encephalitis and GBS. Unvaccinated status, cerebrovascular events, and admission hypoxemia are associated with an increased likelihood of 28-day mortality among these patients.

Association of disease severity and death outcome with vaccination status of admitted COVID-19 patients in delta period of SARS-COV-2 in mixed variety of vaccine background.

To understand the effectual role of COVID-19 vaccination, we must analyze its effectiveness in dampening the disease severity and death outcome in patients who acquire infection and require hospitalization. The goal of this study was to see if there was an association between disease progression in admitted COVID-19 patients and their prior vaccination exposure. A prospective cohort study based on 1640 admitted COVID-19 patients were carried between June 2021 and October 2021. Depending on vaccination exposure they were divided into vaccinated (exposed) and unvaccinated (unexposed) groups, excluding partially vaccinated patients. Disease severity was assessed at admission on severity index scale. Disease progression to mortality or need of mechanical ventilation and survival were taken as outcome. Absolute difference with 95%CI and Risk Ratio were calculated using cross tabulation, Chi square test and multivariable logistic regression analysis. Among 1514 total analyzed cohort (median age, 53 years [IQR, 17,106]; 43.7% from 46 to 65 years of age group, 56.2% males,33.4% with no comorbid factor for disease progression) 369(24.4%) were vaccinated breakthrough cases and 1145(75.6%) were unvaccinated controls. 556(36.7%) progressed to death or mechanical ventilation, 958(63.3%) patients survived and were discharged home. Disease progression to death or mechanical ventilation was significantly associated with decreased likelihood of vaccination (24.9% among vaccinated breakthrough vs 40.5% unvaccinated controls, [Absolute difference -15.6% 95%CI (-10.2% to -20.6%); RR 0.615 95%CI (0.509, 0.744); p <.001]). This association was stronger for old age population and for increase time span between second dose of vaccine and onset of symptoms. There was no statistically significant difference among different types of vaccination and occurrence of outcome when compared to unvaccinated controls (RR 0.607(0.482, 0.763); 0.673(0.339, 1.33) and 0.623(0.441, 0.881) for Inactivated virus vaccine, mRNA and Adenovirus vector-based vaccine respectively. The patients who were fully vaccinated against SARS-COV-2 die or shift to mechanical ventilation less frequently than unvaccinated COVID-19 admitted patients.