In this retrospective study, we evaluated whether baseline medication profiles may be associated with survival or hospitalization due to any reason after COVID-19-related hospitalization in an Austrian population. Hospitalized COVID-19 patients had a higher drug prescription load prior to COVID-hospitalization and increased long-term mortality, especially in patients > 75 years old. Pre-COVID prescription of antipsychotic drugs, antiepileptic drugs, chemotherapy, iron/FA/ B12, beta-blockers, and anticoagulants was significantly associated with increased mortality, whereas patients who were prescribed NSAIDs and other anti-inflammatory drugs prior to COVID-19 hospitalization had a significantly lower risk of all-cause death. Due to our study design, we were able to present the “real life” prescription and mortality rate of patients hospitalized with the diagnosis of COVID-19 in Austria, as well as in a matched control population that was followed from 2020 for up to a maximum of 880 days.
Polypharmacy frequently occurs in patients with COVID-1915 and may be associated with increased morbidity and mortality.15,16 Analyzing the prescription data in the control population, we detected no drug prescription in the investigated medication groups in 77% (19–40 years), 69% (41–64 years), 56% (65–74 years), and 41% (≥ 75 years) of controls. In contrast, 30% (19–40 years), 15% (41–64 years), 6% (65–74 years), and 4% (≥ 75 years) of COVID-19-hospitalized patients had no drug prescription.
We found that the intake of antipsychotic drugs was associated with a significant increased risk of death. The estimated mortality for patients with prescribed antipsychotic drugs was 56.3% (CI: 54.7–57.9) within a two-years follow up in the age group ≥ 75 years as compared to 40.83% (CI: 42.5–39.1) for patients without antipsychotic drugs. The mortality rate for controls with prescribed antipsychotic drugs was 32.9% (CI: 32.1–33.7) as compared to patients not receiving these drugs (11.4%, CI: 11.7–11.1) within two years follow-up for patients ≥ 75 years.
The association of anti-inflammatory medication, such as NSAIDs, with lower mortality could be attributed to the pathophysiology of COVID-19, with a high pro-inflammatory state in the second phase of the disease, also referred to as the cytokine storm phase,19,20 which could be attenuated by anti-inflammatory medication. In patients with high pro-inflammatory state in need of oxygen therapy and SARS-CoV-2-associated lung infiltration, anti-inflammatory therapy (e.g., dexamethasone) was the only pharmacological intervention to reduce mortality.21 However, we cannot exclude the possibility of bias by indication with the selection of possibly healthier patients using NSAIDS on a regular basis because more comorbid patients (e.g., with chronic kidney disease, diabetes, cardiovascular disease, or heart failure) are regularly advised to avoid NSAIDs.
The pronounced association of antipsychotic medication with higher mortality is assumed to be related to the comorbidities in a population that has high prescription rates of such medication, especially at higher ages. Antipsychotic drugs are associated with severe COVID-19 morbidity and mortality.16 Antipsychotic medication is mainly prescribed to patients in resident or nursing homes with dementia or behavioral disorders.22,23 The number of antipsychotic prescriptions is higher in nursing homes (57,1%) compared to residential homes (29,5%),24 emphasizing more frequent prescriptions in a more morbid population. Therefore, chronic psychotic medication use at more advanced ages is most probably indicative of patients with severe impairments.25–27
Among nursing home residents, a significant positive association was found between the total number of medications and 30-day COVID-related adjusted mortality.17 After additional correction for dementia and use of Proton pump inhibitors (PPI), vitamin D, antipsychotics, and antithrombotics, this effect was no longer significant, suggesting that polypharmacy itself may not be the problem, but the type of medication. In our analyses, polypharmacy did not remain significant after correcting for several medication groups.
In patients who were discharged alive from a COVID-19-related hospitalization, the risk of post discharge death of patients > 64 of age within 180 days was nearly twice that observed in historical controls admitted to the hospital with influenza. 12 Although readmission after COVID-19-related hospitalization was common, the frequency by 180 days was similar to the frequency of patients discharged alive from influenza-related hospitalization. Furthermore, crude differences in drug use between COVID-19 patients and the general population were found in antithrombotic agents, antiepileptics, anti-gout preparations, and cardiac therapy. 14
Scant data are available on clinical outcomes in patients discharged alive from COVID-19 hospitalization. Data from a large study with patients discharged after COVID-19 reported an increased risk of readmission and mortality during a follow-up of 140 days.10 In a German cohort of hospitalized COVID-19 patients, 30-day all-cause mortality was 23,9% and 180-day all-cause mortality 29,6%. Another study after COVID-19 hospitalization among patients in Italy reported an 8% age-related overall relative increase in all-cause death after 6 months of follow-up.13 However, age was the only independent predictor of mortality after multivariate analysis. Another report from the US investigated the 12-month mortality after recovery from the initial episode of COVID-19 and reported a significantly higher 12-month adjusted all-cause mortality risk for patients with severe COVID-19 compared to both COVID-19-negative patients and mild COVID-19 patients. A large retrospective long-term outcome cohort study indicated an overall 2-year mortality risk that was worse by day 180 among those infected with COVID-19 compared to matched uninfected comparators, but there was no excess mortality during the subsequent 1,5 years.28 In our study, we observed increased long-term mortality and increased risk of hospitalization due to any reason after surviving COVID-19 hospitalization. Mortality was more pronounced within the first 50 days after index-hospitalization.
The main strength of this study is the use of a large, representative, real-world national database. The retrospective design, however, is a limitation, which we sought to mitigate by including several potential confounding factors in the statistical models and performing propensity score matching to support meaningful comparisons. Yet, as in any observational research, even with the large sample size and long-term follow-up, unmeasured confounding leading to bias is still possible. The study population was drawn exclusively from the Austrian Health Insurance Funds, raising potential concerns about the generalizability and external validity of the findings to a broader patient population. Furthermore, no information was available from the Austrian Insurance Fund on vaccination or intensive care in hospitals. However, vaccination was first available in the very end of 2020 and therefore, it may not be an important factor for patients hospitalized with COVID-19 in 2020.
In conclusion, this large Austrian cohort of COVID-19-hospitalized patients and matched controls an increased short- and long-term risk of mortality was observed. Patients hospitalized with COVID-19 had a higher drug prescription load (polypharmacy). Antipsychotics were significantly associated with poor survival in patients > 40 years old. Our findings may help identify the most vulnerable patients at higher risk of mortality after COVID-19 discharge regardless of age by screening prescribed medication groups, with implications for preventive measures. Antipsychotics are assumed to be an underrecognized medication group linked to worse patient outcomes after COVID-19 hospitalization.