COVID-19 hospitalization linked to long-term organ damage and mortality

By Dr. Priyom Bose, Ph.D.Reviewed by Benedette Cuffari, M.Sc.Mar 7 2025

A large-scale French study finds that patients hospitalized with COVID-19 face a significantly higher risk of long-term organ disorders, hospitalization, and mortality for up to 30 months post-infection.

Study: Long-term health outcomes following hospitalisation for COVID-19: a 30- month cohort analysis.  Image Credit: Ground Picture / Shutterstock.com

A recent Infectious Diseases study determines the risk of long-term health complications following recovery from the coronavirus disease 2019 (COVID-19).

The global impact of COVID-19

Since its emergence at the end of 2019, over 700 million individuals throughout the world have been infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen responsible for COVID-19. SARS-CoV-2 infection can lead to a wide range of symptoms, with some individuals remaining asymptomatic, whereas others may experience severe illness that can lead to death. To date, over seven million deaths have been directly attributed to COVID-19.

Long COVID is characterized by symptoms that persist for over one month following recovery from acute SARS-CoV-2 infection. Current estimates indicate that approximately 70% of patients who required hospitalization due to COVID-19 are at a greater risk of developing long COVID.

In addition to long COVID, SARS-CoV-2 infection also increases the risk of damage to various organs. Moreover, one recent study reported that COVID-19 impacted the affected individual’s health status for at least three years after infection onset; however, the follow-up period of this study was limited.

About the study

The current retrospective cohort study assessed the risk of the long-term health complications of COVID-19 using French medico-administrative data (Système National des Données de Santé-SNDS). This dataset included detailed healthcare records such as medications, procedures, and diagnosis of about 99% of the French population.

The risks of all-cause hospitalization, all-cause mortality, and hospitalization for specific organ disorders within 30 months following COVID-19 hospitalization were quantified and compared with a matched control group from the general population in France.

The study cohort comprised COVID-19-exposed people 18 years of age and older who required hospitalization. These patients were hospitalized for at least one day and were discharged alive between January 1, 2020, and August 30, 2020. The non-exposed general population (GP) control group included adults who did not require hospitalization for SARS-CoV-2 infection during the study period.

All study participants were monitored for up to 30 months after the study commenced or until death if it occurred before this time point. COVID-19 outcomes including all-cause hospitalization, all-cause mortality, and hospitalization for various organ-specific disorders linked to psychiatric, respiratory, neurological, cardiovascular, liver or renal disorders, and diabetes were considered.

Study findings

A total of 63,990 individuals were included in the COVID-19 hospitalized group and 319,891 were matched at a 1:5 ratio in the control group. The mean age of the study participants was 53.1 years, about 53% of whom were male.

Most individuals in the COVID-19 hospitalized group were from deprived areas, obese, smokers, or had a history of alcohol abuse. As comparied to the control group, COVID-19 hospitalized patients were more likely to be diagnosed with pre-existing comorbidities.

During the follow-up period, all-cause mortality was estimated to be 17.7% in the COVID-19 hospitalized group and 8.5% in the GP control group. The all-cause hospitalization was estimated to be 16,334 and 12,095 for every 100,000 person-years in the COVID-19 hospitalized and GP control groups, respectively. These findings indicate that the COVID-19 hospitalization group was at a greater risk of all-cause mortality and all-cause hospitalization for 30 months after the initial infection with SARS-CoV-2.

As compared to the GP control group, those in the COVID-19 hospitalized group were at a significantly greater risk of hospitalization for long-term health events linked to various organ systems disorders. These included cardiovascular disorders like heart failure, other cardiomyopathy, cardiac rhythm, or conduction disorders, as well as respiratory disorders including chronic lower respiratory disorders and thromboembolic events for up to 30 months after hospital discharge.

Study participants from the COVID-19 hospitalized group were also at an increased risk of developing diabetes, neurological disorders, psychiatric disorders, and chronic renal failure than the control group.

Conclusions

Patients who required hospitalization due to SARS-CoV-2 infection are at an increased risk of all-cause mortality and of all-cause hospitalization for 30 months after the initial infection. A greater risk of various organ disorders prevailed for the first six months, followed by a gradual decrease while remaining significantly higher for the next 24 months.

Taken together, the study findings emphasize the importance of closely monitoring patients who have recovered from COVID-19 for extended periods to reduce their risk of developing long-term adverse outcomes. Additional research is also needed to elucidate the pathophysiological changes involved in post-COVID-19 disease.