Demographic and clinical characteristics
Table 1 shows the main characteristics by sex and final health outcome. The proportion of women and men were almost equal, 78% of patients were older than 50 years. High mortality was observed in patients older than 65 years, and the association between age and final health outcome was statistically significant (p value 0.03). Most patients had low educational attainment (61% reached just primary school) and women had lower levels of education. High proportion of comorbidities, mostly non-communicable diseases (around 45%), was identified. Women exhibited higher prevalence of comorbidities (57.33%) than men (34.15%). Hypertension had 17.83% prevalence, followed by diabetes with 14.65%, and in the same way these were higher in women than men (p value 0.00). People with comorbidities had a high mortality (36.36%) and it was higher in patients with hypertension 18.18%.
The average time from onset of symptoms until admission was 7.4 days, being longer in men (8.03) than women (6.73). Cough (77.07%) and dyspnea (75.64%) were the most prevalent signs and symptoms, followed by fever (58.60%) and fatigue (55.41%); all of these were higher in men than women. Regard association between symptoms and mortality they had not significant differences. Overall, only fever had statistically significant differences between sex groups (p value 0.00). Anosmia, runny nose, exanthema, and conjunctive injection were almost absent. All patients had tachypnea (respiratory frequency mean 27.17) and the percentage of oxygen saturation was lower than 90% in all patients (mean 76.96%; women 76.85% and men 77.06%), no statistically significant differences were found in these rates. However, patients who died had significantly lower levels of saturation (69.27%) (p value 0.00). Temperature, systolic blood pressure, pulse and Glasgow scale were within normal parameters between sex groups.
In relation to illness severity, NEWS score was 6.68 points on average, and higher in men (6.90) than women (6.44). Most (50.96%) of the patients had a moderate NEWS Score but a high proportion (35.03%) had a severe NEWS score, and both were higher prevalent in men than women.
The final health outcome is displayed in Table 2. A high proportion of patients died 35.03% and this was higher in men (39.02%) than women (32.00%). Mortality in terms of NEWS score was varied, patients with moderate score had higher mortality (54.55%) more prevalent in women (60.87%). Patients with severe score showed a mortality prevalence of 41.82% and it was higher in men group (43.75%); and the differences were statistically significant (p value: 0.02). According to age, high mortality was observed in the more than 65 years group (52.73%) in which women had (56.52%) and men (50.00%); likewise, a high mortality was observed in the 50 to 64 age group in which men had (43.75%) and women (17.39%), besides those differences were statistically significant (p value: 0.02).
Results of the logistic regression analysis with all variables adjusted by age showed that for every day of illness the probability to die increased by 4% (OR 1.04, 95% IC: 0.95-1.12 and women had higher probability to die 96% (OR: 1.96, 95% IC: 0.82-3.22) than men.
The presence of comorbidities more than doubled the probability to die (OR: 2.38, 95% IC: 1.14-4.93); similarly, for diabetes (OR: 2.23, 95% IC: 0.76-6.48) whereas hypertension increased probability by 25% (OR: 1.25, 95% IC: 0.51-3.08). Those who had both pathologies diabetes and hypertension increased the risk to die but not significantly (OR: 2.43, 95% IC: 0.82-7.21). Men with diabetes had higher probability to die (OR: 2.54, 95% IC: 0.38-16.69) compared with women, while women with hypertension had more risk (OR: 2.70, 95% IC: 0.84-8.61).
Table 3 shows laboratory findings separately by sex and final health outcome. Means of leukocytes and neutrophils were higher than expected, while lymphocytes count, showed lymphopenia in men but not women (p value: 0.02). Patients who died had higher levels of leukocytes and neutrophils statistically significant comparing with those survived (p value: 0.00).
Deceased patients had significantly elevated inflammatory and infectious markers (p value: <0.05). In patients who died several blood parameters had higher mean levels, such as fibrinogen, urea, AST, LDH, PCR, D-dimer, troponin, ferritin, and lactate. Men, and patients who died, exhibited significantly worse results (p value: 0.05). Coagulation markers were lower than reference and were significantly different between men and women (p value: < 0.02). Most of the patients presented hypoxia (PO2 mean: 56.58 mmHg (53.45-59.72) but differences were not significant between groups.