What is different about the presentation of COVID-19 in frail or older adults?

Posted on May 10, 2020 by Jennifer Mullowney


Aging adults experience a decline in the responsiveness and effectiveness of their immune system, which makes it more difficult for their body to fight off viruses, infection and  disease.  Additionally, 74% of Canadian older adults , aged 65 and older, live with at least one chronic condition which further impedes the body’s ability to fight and recover from viruses such as SARS-COV-2 (COVID -19). Aging may also complicate diagnosis, as older adults with respiratory viruses may present atypically. The most commonly reported symptoms among older adults is shortness of breath,  fever, and cough.  The definition of fever may need to be altered for older adults, as it is frequently blunted or absent in serious infection.

I.   Background

  • Severe acute respiratory syndrome coronavirus (SARS-CoV-2 ) infection can cause significant morbidity and a higher mortality rate in older adults compared to younger adults. (2)
  • Those with underlying conditions such as hypertension, cardiovascular disease, diabetes, chronic kidney disease are at increased risk possibly due to the alterations in the angiotensin converting enzyme 2 (ACE 2) receptors produced by ACE 1 inhibitors. (2)
  • Infections in older and frail adults often present atypically, confounding identification and management. Contributing factors for adverse outcomes in morbidity and mortality include the physiological processes of aging, comorbidities, polypharmacy, and the impact of congregate living in aged-care facilities. (3)
  • Older adults may present with mild symptoms that are disproportionate to the severity of their illness (7)
  • The etiology of the relationship between age and severity of illness remains a point of discussion. It is proposed that differences in the immune and inflammatory responses to the virus vary with age, as well as host factors. (2)

II.   What is unique about COVID-19 & older adults

  • The immune system of older adults undergo age-related changes (immune senescence) which affect many cellular and molecular processes of both the innate and adaptive immune system, as well as coordinating and mounting an immune response. (3)
  • The median duration from symptom onset to death is 11.5 days in person >70 years vs 14 days in younger persons. (5)
  • Atypical COVID-19 symptoms include delirium, falls, generalized weakness, malaise, function decline, conjunctivitis, anorexia, sputum production, dizziness, headache, rhinorrhea, chest pain, hemoptysis, diarrhea, nausea/vomiting, abdominal pain, nasal congestion, and anosmia. (7,8)
  • Only 20-30% of geriatric patients with infection present with fever (7)
  • The definition of fever may need to be altered for older adults, as it may not be a sufficiently sensitive sign in older adults, as the thermoregulation response is frequently blunted or absent in serious infection. While conclusive  data on fever in COVID-19 in older adults is lacking, data on fever in influenza, another respiratory virus with significant mortality in older adults, sheds some light on the sensitivity of fever in older adults. (5)
  • The threshold for diagnosing fever should be lower, ie 37.5 C or an increase >1.5C from baseline (6)
  • The Infection Disease Society of America recommends modifying the definition of fever for older adults to:
    • A single oral temperature over 100 F or
    • 2 oral repeated temperatures over 99 F
    • An increase in temperature of 2 degrees F over the baseline temperature (5)

III.   Typical clinical presentation

  • The most common presenting symptoms of COVID -19 among the general population are fever (98%), cough (76%), dyspnea (55%), and myalgias or fatigue (up to 44%)  (4)
  • Around 15% of cases may go on to develop acute respiratory distress syndrome for 5 days but may last up to 14 days. Viral shedding may last up to 37 days. (3)
  • Over 95% of hospitalized adults have abnormal chest computer tomography with focal unilateral ground glass opacities with a reticular pattern, fibrotic streaks and air bronchogram.(2)
  • From a laboratory point of view, lymphocytopenia, hypoalbuminemia, increased ferritin, decreased procalcitonin and very high angiotensin II levels are commonly  present. Elevated d-dimer levels are furthermore associated with increased mortality for adults on ventilators. (2)
  • Fever, cough, dyspnea, myalgia and fatigue are all commonly reported symptoms in older adults, with one study on 21 critically ill patients with positive COVID-192 infection with a mean age of 70, found that the three most frequently reported symptoms were shortness of breath (76%), fever (52%), cough (48%) (2)
  • Prevalence rates of community acquired transmission of COVID-19 however remain uncertain as it appears a number of older adults may not show any symptoms at time of diagnosis. Data collected from serial point prevalence surveys in the United States of an outbreak at a skilled nursing facility where 57 of its 89 residents (645) tested positive for SAR-COV-19  27 residents were reported as asymptomatic at the time of testing. Among the 27 residents classified as asymptomatic, 15 reported no symptoms and 12 reported only stable chronic symptoms. In the 7 days after their positive test, 24 of the 27 asymptomatic residents (89%) had onset of symptoms and were recategorized as presymptomatic. The most common new symptoms were fever (71%), cough (54%) and malaise (42%) followed by shortness of breath, confusion, rhinorrhea/congestion, diarrhea, sore throat, dizziness and headache. (1)
  • In practice, anticipate atypical presentation in patients over the age of 75 (1) Older and frail adults with a modified definition of fever and respiratory symptoms (cough) who test negative for influenza should be considered for priority COVID-19 testing. Symptoms may be unreliable, therefore consider early diagnostic testing.  If the individual is hemodynamically stable and no, or only mild, clinical symptoms, it is wise to conduct COVID-19 testing in locations outside the emergency department when possible. (5)

Questions? Comments? Does this need to be updated? Do you have valuable points to add ? Please email ask.reakt@ubc.ca.


  1. Arons M. Hatfield KM. Reddy S. Kimball A. et al. Presymptomatic SARS-COV-2 Infections and Transmission in a Skilled Nursing Facility. NEJM. April 24, 2020 DOI: 10.1056/NEJMoa2008457
  2. Morley, J.E., Vellas, B. COVID-19 and Older Adult. J Nutr Health Aging 24, 364–365 (2020). https://doi.org/10.1007/s12603-020-1349-9
  3. Nikolich-Zugich, J., Knox, K.S., Rios, C.T. et al. SARS-CoV-2 and COVID-19 in older adults: what we may expect regarding pathogenesis, immune responses, and outcomes. GeroScience (2020). https://doi.org/10.1007/s11357-020-00186-0
  4. Zainab S. Kalayanamitra R. Mclafferty B. et al.  COVID‐19 and Older Adults: What We Know. J Am Geriatr Soc.07 April 2020.https://doi.org/10.1111/jgs.16472
  5. Malone, M., Hogan, T., Perry, A., Biese, K.m Bonner, A., Pagel, P. & K. Unroe. (2020). COVID-19 in Older Adults: Key Points for Emergency Department Providers. Journal of Geriatric Emergency Medicine 1(4): 1-11. Retrieved from: https://gedcollaborative.com/article/covid-19-in-older-adults-key-points-for-emergency-department-providers/
  6. Jarrett PG, Rockwood K, Carver D, Stolee P, Cosway S. Illness presentation in elderly patients. Arch Intern Med.1995;155(10):1060-4.
  7. Jung, YJ, Yoon JL, Kim HS, Lee AY, Kim MY, Cho JJ. Atypical clinical presentation of geriatric syndrome in elderly patients with pneumonia or coronary artery disease. Ann of Geri Med and Res. 2017;21(4):158-63.
  8. Dadamo H, Yoshikawa T, Ouslander JG. Coronavirus Disease 2019 in geriatrics and long-term care: The ABCDs of COVID-19. J Am Geriatr Soc. 2020. doi: 10.1111/jgs.16445. [Epub ahead of print]


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