Demographics and Patient Characteristics
Our study included 1,572,815 individuals, with 22,230 (1.4%) in the PTX group and 1,550,585 (98.6%) in the non-PTX group (Table 1). The PTX group consisted of more Hispanic patients (31.8% vs. 21.3%) and fewer White patients (44.2% vs. 51.1%) than the non-PTX group (p < 0.001). The PTX group also had a higher proportion of males (65.8% vs. 51.6%, p < 0.001). Patient ages differed between both groups and sexes. There were more patients 50-69 years old in the PTX group (46.7% vs. 37.0%, p < 0.001). Additionally, the average age for females was slightly higher in the PTX group (65.9 years vs. 63.1 years), while it was almost identical for males across both groups.
There was a small difference in patient income between the two groups and no difference in insurance. There were more individuals earning less than $49,999 a year in the PTX group than in the non-PTX group (36.4% vs. 34.1%, p = 0.004). However, there were no substantial differences in insurance status between the two groups (p = 0.113).
There were differences in hospital division distribution, bed size, and teaching status between the two groups. The West South-Central hospital division saw a significantly higher percentage of PTX cases (18.1% vs. 14.2%, p < 0.001). There was also a higher proportion of PTX patients at large hospitals (50.4% vs. 46.6%, p < 0.001) and urban, teaching hospitals (76.3% vs. 71.5%, p < 0.001).
Comorbidity profiles differed between the two groups. PTX patients were less likely to have coronary artery disease (15.0% vs. 17.9%, p < 0.001), myocardial infarction (3.1% vs. 4.2%, p < 0.001), hypertension (62.6% vs. 64.9%, p = 0.001), smoking history (19.6% vs. 25.6%, p < 0.001), chronic kidney disease (10.6% vs. 12.6%, p < 0.001), hypothyroidism (10.5% vs. 13.3%, p < 0.001), depression (7.6% vs. 11.0%, p < 0.001), and dementia (5.8% vs. 12.2%, p < 0.001). They were more likely to have Type 2 diabetes (41.6% vs. 40.1%, p = 0.032), cancer (5.0% vs. 4.2%, p = 0.010), and obesity (28.6% vs. 26.4%, p = 0.001). There were no significant differences in drug abuse, chronic pulmonary disease, peripheral vascular disease, autoimmune disease, or AIDS prevalence. All demographics and patient characteristics from the multivariate analysis are in Table 1, with the PSM results in Table 3.
In-Hospital Morbidity and Mortality
In-hospital mortality between PTX and non-PTX COVID-19 patients differed significantly. Of the 1,550,585 non-PTX patients, 12.6% died in the hospital. This was markedly lower than the 65.8% mortality rate among the 22,230 PTX patients. The adjusted odds ratio (AOR) for in-hospital mortality was significantly high at 15.9 (95% CI 14.9–17.0), indicating a substantially higher risk of in-hospital death for PTX patients (Table 2). PSM of 44,460 COVID-19 patients (half with PTX, half without) revealed the in-hospital mortality rate was 14.4% for non-PTX patients but 65.8% for PTX patients.
PTX patients experienced a significantly higher rate of in-hospital complications. For example, the AOR for acute liver failure and sudden cardiac arrest were 7.2 (95% CI 6.4–8.1) and 7.0 (95% CI 6.5–7.6), respectively. Additionally, these patients experienced acute kidney injury (AKI) (AOR 4.4, 95% CI 4.1–4.6), venous thromboembolism (AOR 3.5, 95% CI 3.2–3.8), cardiogenic shock (AOR 4.2, 95% CI 3.5–5.1), hemodialysis (AOR 4.0, 95% CI 3.6–4.3), cerebrovascular accident (AOR 2.9, 95% CI 2.5–3.3), and tracheostomy placement (AOR 14.1, 95% CI 12.8–15.5). PSM yielded similar results. PTX patients experienced a higher prevalence of acute liver failure (AOR 6.7, 95% CI 5.0–9.0), sudden cardiac arrest (AOR 7.4, 95% CI 6.0–9.2), and vasopressor use (AOR 7.5, 95% CI 6.2–9.1). PTX patients had greater incidences of cerebrovascular accidents (AOR 3.0, 95% CI 2.3–4.0) and an increased need for mechanical circulatory support (AOR 11.5, 95% CI 6.4–20.6). They also showed a greater incidence of AKI (AOR 4.1, 95% CI 3.7–4.5), venous thromboembolism (AOR 3.2, 95% CI 2.7–3.8), cardiogenic shock (AOR 5.1, 95% CI 3.3–7.9), and hemodialysis (AOR 3.7, 95% CI 3.2–4.4) (Table 4).
Of note, the need for chest tube placement was remarkably higher among PTX patients at 59.8% compared to 0.6% in non-PTX patients, with an AOR of 244.9 (95% CI 226.3–265.1) (Table 2). Results from PSM showed increased rates of both tracheostomy placement (AOR 14.2, 95% CI 10.5–19.0) and chest tube placement (AOR 231.3, 95% CI 163.1–328.0) (Table 4). PSM showed similar trends for mechanical ventilation, with PTX patients having much higher rates of mechanical ventilation, even when separated into invasive (AOR of 23.1; 95% CI 20.4–26.2) and non-invasive (AOR 3.8; 95% CI 3.3–4.5) support (Table 4).
In-Hospital Quality Measures
The in-hospital quality measures of total charges for each patient and LOS were compared between the PTX and non-PTX cohorts. PTX patients required considerably more resources as reflected in total charges. The mean total hospitalization charge for PTX patients was notably higher than for non-PTX patients ($435,508 vs. $86,822), with a difference in adjusted total charge for PTX patients being $336,782 greater. The mean LOS was also extended for PTX patients at 23.6 days, compared to 7.8 days for non-PTX patients; the adjusted LOS was 15.3 days longer for PTX patients (Table 2). Data from PSM corroborated this trend: PTX patients had a significantly higher mean total hospitalization charge at $435,508 compared to $96,668 for non-PTX patients, which is an adjusted total charge of $320,978 more. Similarly, the mean LOS for PTX patients was 23.6 days, compared to 8.6 days for non-PTX patients, marking an adjusted LOS 14.9 days longer (Table 4).
Disposition
Hospital dispositions between the two groups differed significantly. More non-PTX patients left against medical advice (1.1% vs. 0.3%), were discharged to home health care (13.1% vs. 5.4%), were discharged routinely (51.5% vs. 7.6%), or were transferred to another care facility (18.6% vs. 16.4%). In contrast, more PTX patients were transferred to a short-term hospital (3.0% vs. 4.5%). PSM produced similar results in outcomes. For example, 0.9% of non-PTX patients left against medical advice compared to 0.3% of PTX patients. These differences, reflected in both AOR and PSM data, highlight the impact of PTX on the course of recovery in COVID-19 patients (Tables 2 and 4).