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Assessment of Dependence in Activities of Daily Living Among Older Patients in an Acute Care Unit
Published on: September 30, 2020
Age-dependence of healthcare interventions for COVID-19 in Ontario, Canada
Irena Papst1, Michael Li2,3, David Champredon4
1Center for Applied Mathematics, Cornell University, Ithaca, USA. ip98@cornell.edu.
Insights
COVID-19 hospitalizations significantly impact middle-aged and younger seniors, not just the elderly. Vaccination strategies should target these groups to prevent serious illness and reduce healthcare system strain.
Area of Science:
- Public Health
- Epidemiology
- Infectious Diseases
Background:
- Patient age is a critical risk factor for COVID-19 severity.
- While COVID-19 deaths are concentrated in older populations, less is known about age distributions for serious medical interventions.
- Understanding these distributions is crucial for healthcare system planning and vaccination strategies.
Purpose of the Study:
- To quantify the relationship between COVID-19 patient age and serious medical outcomes, including hospitalizations and intensive care.
- To analyze the age-specific probabilities of hospitalization and survival following COVID-19 infection.
Main Methods:
- Analysis of 277,555 SARS-CoV-2 infection records in Ontario, Canada (Jan 2020 - Feb 2021).
- Estimation of age distributions for hospitalizations, ICU admissions, intubations, and ventilations.
- Calculation of hospitalization probability given infection and survival probability given hospitalization.
Main Results:
- Hospitalizations peak in a broad range from ages 60-90, contrasting with deaths concentrated in ages 80+.
- The probability of hospitalization reaches 27.8% at age 80.
- Survival probability after hospitalization declines significantly after age 40, with a 54-year-old having a 91.7% chance of survival.
Conclusions:
- Middle-aged individuals and younger seniors show a significant need for hospitalization, a trend not evident from death distributions alone.
- COVID-19 survival rates post-hospitalization are lower than often perceived for individuals over 40.
- Vaccination efforts should extend beyond the elderly to include middle-aged and younger seniors to mitigate serious illness and healthcare system burden.
Background:
Patient age is one of the most salient clinical indicators of risk from COVID-19. Age-specific distributions of known SARS-CoV-2 infections and COVID-19-related deaths are available for many regions. Less attention has been given to the age distributions of serious medical interventions administered to COVID-19 patients, which could reveal sources of potential pressure on the healthcare system should SARS-CoV-2 prevalence increase, and could inform mass vaccination strategies. The aim of this study is to quantify the relationship between COVID-19 patient age and serious outcomes of the disease, beyond fatalities alone.
Methods:
We analysed 277,555 known SARS-CoV-2 infection records for Ontario, Canada, from 23 January 2020 to 16 February 2021 and estimated the age distributions of hospitalizations, Intensive Care Unit admissions, intubations, and ventilations. We quantified the probability of hospitalization given known SARS-CoV-2 infection, and of survival given COVID-19-related hospitalization.
Results:
The distribution of hospitalizations peaks with a wide plateau covering ages 60-90, whereas deaths are concentrated in ages 80+. The estimated probability of hospitalization given known infection reaches a maximum of 27.8% at age 80 (95% CI 26.0%-29.7%). The probability of survival given hospitalization is nearly 100% for adults younger than 40, but declines substantially after this age; for example, a hospitalized 54-year-old patient has a 91.7% chance of surviving COVID-19 (95% CI 88.3%-94.4%).
Conclusions:
Our study demonstrates a significant need for hospitalization in middle-aged individuals and young seniors. This need is not captured by the distribution of deaths, which is heavily concentrated in very old ages. The probability of survival given hospitalization for COVID-19 is lower than is generally perceived for patients over 40. If acute care capacity is exceeded due to an increase in COVID-19 prevalence, the distribution of deaths could expand toward younger ages. These results suggest that vaccine programs should aim to prevent infection not only in old seniors, but also in young seniors and middle-aged individuals, to protect them from serious illness and to limit stress on the healthcare system.
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