Clinical Manifestations and Outcomes of Older Patients with COVID-19: A Comprehensive Review

Article information

Tuberc Respir Dis. 2024;87(2):145-154
Publication date (electronic) : 2024 February 16
doi :
Division of Allergy, Pulmonary, and Critical Care Medicine, Department of Internal Medicine, Chungnam National University Hospital, Chungnam National University College of Medicine, Daejeon, Republic of Korea
Address for correspondence Song I Lee, M.D., Ph.D. Division of Allergy, Pulmonary, and Critical Care Medicine, Department of Internal Medicine, Chungnam National University Hospital, Chungnam National University College of Medicine, 282 Munhwa-ro, Jung-gu, Daejeon 35015, Republic of Korea Phone 82-42-280-6816 E-mail
Received 2023 October 3; Revised 2023 November 17; Accepted 2024 January 13.


The consequences of coronavirus disease 2019 (COVID-19) are particularly severe in older adults with a disproportionate number of severe and fatal outcomes. Therefore, this integrative review aimed to provide a comprehensive overview of the clinical characteristics, management approaches, and prognosis of older patients diagnosed with COVID-19. Common clinical presentations in older patients include fever, cough, and dyspnea. Additionally, preexisting comorbidities, especially diabetes and pulmonary and cardiovascular diseases, were frequently observed and associated with adverse outcomes. Management strategies varied, however, early diagnosis, vigilant monitoring, and multidisciplinary care were identified as key factors for enhancing patient outcomes. Nonetheless, the prognosis remains guarded for older patients, with increased rates of hospitalization, mechanical ventilation, and mortality. However, timely therapeutic interventions, especially antiviral and supportive treatments, have demonstrated some efficacy in mitigating the severe consequences in this age group. In conclusion, while older adults remain highly susceptible to severe outcomes from COVID-19, early intervention, rigorous monitoring, and comprehensive care can play a pivotal role in improving their clinical outcomes.

Key Figure


Coronavirus disease 2019 (COVID-19) is an infectious illness caused by the severe acute respiratory syndrome coronavirus 2. It was initially detected in Wuhan, China in December 2019, and quickly became a global pandemic [1]. As of July 5, 2023, the World Health Organization (WHO) has reported 767,726,861 confirmed cases of COVID-19 globally, with 6,948,764 deaths [2]. Factors associated with COVID-19 mortality include older age; male sex; underlying health conditions; laboratory biomarkers such as lymphocyte count, serum lactate dehydrogenase (LDH), and C-reactive protein (CRP) levels; and a high viral load during hospitalization [3,4]. Among these factors, older age is well recognized to be associated with increased severity and higher mortality rates [5-9].

As of July 5, 2023, the Republic of Korea has reported 32,256,154 confirmed cases of COVID-19, with 35,071 deaths [10]. According to the Korea Disease Control and Prevention Agency, the percentage of deaths has increased in older age groups (60 to 69 years, 11.36%; 70 to 79 years, 22.69%; ≥80 years, 59.64%) accompanied by higher fatality rates (60 to 69 years, 0.11%; 70 to 79 years 0.43%; ≥80 years, 1.85%) [11]. An age range of 60 to 65 years or older is defined as the criterion for older people associated with poor prognosis in COVID-19 patients. Therefore, this review was conducted to explore the characteristics and prognosis of older patients diagnosed with COVID-19.

This review is crucial for a thorough examination of the clinical manifestations, treatments, and prognostic outcomes in older patients infected with COVID-19. It aims to analyze the ways in which the virus impacts this vulnerable age group, focusing on their symptoms, treatment responses, and factors influencing health outcomes. This in-depth analysis is helpful for improving our understanding of COVID-19’s dynamics in older patients, which is essential for developing more effective clinical strategies and public health policies specifically designed for this high-risk group.

Clinical Features and Common Comorbidities

Symptoms such as fever, cough, dyspnea, myalgia, fatigue, diarrhea, and an asymptomatic presentation can manifest in older patients with COVID-19 [12]. Moreover, the frequency of these symptoms varies across studies. In a study conducted by Li et al. [13], focusing on patients with COVID-19 aged ≥60 years, commonly observed symptoms were fever (78.9%), cough (49%), and dyspnea (31.9%). Similarly, a systematic review and meta-analysis by Singhal et al. [14] on older patients with COVID-19 revealed that fever, cough, and dyspnea were common symptoms. Moreover, when comparing younger and older patients, a higher occurrence of dyspnea [15] and shortness of breath [16] was observed among older patients.

Furthermore, the older patient population has a higher prevalence of multimorbidity, characterized by the coexistence of multiple underlying health conditions [17,18]. The prevalence of one or more comorbidities was approximately 81% among older patients, with hypertension, diabetes, and cardiovascular disease being most common [14]. Similarly, in other studies, older patients had a higher prevalence of hypertension, diabetes, coronary heart disease, and chronic obstructive lung disease [16,19].

Laboratory and Radiologic Findings

Older patients with COVID-19 often have different laboratory findings than younger patients. For example, lymphopenia and leukopenia are frequently observed in older patients [12,14], along with elevated CRP levels [12]. In a study by Wei et al. [20], older patients had higher levels of neutrophils, CRP, aspartate aminotransferase, LDH, glucose, blood urea nitrogen, and creatinine, but lower counts of lymphocytes, hemoglobin, and platelets than younger and middle-aged patients. In study of Ibrahim et al. [21], patients with COVID-19 aged ≥65 years had higher neutrophil counts and lower lymphocyte counts. They also showed increased levels of creatinine, creatine kinase MB, glucose, LDH, bilirubin, D-dimer, and erythrocyte sedimentation rate compared with younger patients. Additionally, study of Liu et al. [22] revealed significant variations in lymphocyte decrease and monocyte increase among different age groups, with leukocytosis and lymphopenia being particularly prominent in older patients.

On radiological evaluation, the predominant manifestations of COVID-19 often involve airspace abnormalities such as consolidations or ground-glass opacities (GGO) [23]. Figure 1 illustrates examples of the radiological findings of COVID-19. These are typically bilateral, situated peripherally, and primarily found in the lower lung fields [23]. Specifically, in older patients, bilateral lung infiltration is the most observed feature [14]. In study of Statsenko et al. [24], increasing age was associated with greater lung involvement on radiologic images, and cases with GGO were more frequently observed. In a study by Sano et al. [25], computed tomography scans of patients with COVID-19 aged ≥75 years predominantly showed non-segmental, peripherally dominant GGO. However, when comparing older and younger patients, some studies have highlighted cases wherein unilateral findings were more prevalent [19] or where imaging results showed no significant age-related differences [26].

Fig. 1.

Radiologic findings of older patients with coronavirus disease 2019 (COVID-19). (A, B) Normal lung on radiography and computed tomography (CT), (C, D) ground-glass opacities on chest X-ray and CT, (E, F) consolidation on chest Xray and CT, and (G, H) fibrosis on chest X-ray and CT. L: left; R: right; PA: posterior anterior; AP: anterior posterior.

Treatment and Prevention

Older adults [16,27,28], unvaccinated individuals [29,30], and those with certain medical conditions [31-33] face a higher risk of severe COVID-19. Vaccination reduces this risk, and for vaccinated people who are 65 years of age or older or have other risk factors, it may help them get better.

Figure 2 illustrates an overview of the treatment for patients with COVID-19 [34]. In non-hospitalized patients with mild-to-moderate illness, treatment typically involves symptom management combined with the administration of ritonavir-boosted nirmatrelvir (Paxlovid, Pfizer, New York, NY, USA) [35-37] or remdesivir [38,39]. Cases wherein these two drugs are unfeasible, molnupiravir may be considered [35]. In a study [35] involving patients with COVID-19 residing in nursing homes with an average age of 84.8 years, both molnupiravir and paxlovid reduced hospitalizations, intensive care unit admissions, mortality, and the need for invasive mechanical ventilation (MV) compared to patients not treated with antiviral agents. Furthermore, initiating treatment within 5 days of symptom onset appears to offer greater risk reduction.

Fig. 2.

Treatment of older patients with COVID-19[34]. SARS-CoV-2: severe acute respiratory syndrome coronavirus-2; PO: per oral; IV: intravenous; HFNC: high-flow nasal cannula; NIV: non-invasive ventilation; MV: mechanical ventilation; ECMO: extracorporeal membrane oxygenation.

However, in hospitalized patients, the treatment approach varies according to disease severity. For patients who do not require an oxygen supply, neither dexamethasone nor other systemic corticosteroids are recommended [40]; however, remdesivir may be considered [41]. Moreover, remdesivir can be administered in patients requiring minimal conventional oxygen [41,42], however, most patients requiring conventional oxygen may benefit from either a combination of dexamethasone and remdesivir [42] or dexamethasone monotherapy [40,43]. According to a recent review by the Cochrane Library [41], remdesivir administration in patients with moderate-to-severe COVID-19 resulted in a slight promotion of clinical improvement within 28 days and indicated a potential reduction in the risk of clinical deterioration. On the other hand, the concurrent use of oral baricitinib [44,45] or intravenous tocilizumab [46] should be explored in rapidly deteriorating patients. For those requiring interventions such as high-flow nasal cannula, non-invasive ventilation, MV, or extracorporeal membrane oxygenation (ECMO), the addition of oral baricitinib [44,47] or intravenous tocilizumab [46,48] to dexamethasone [40,43] is feasible. When administered to older patients, both tocilizumab [48] and baricitinib [47] have been observed to reduce the risk of mortality. In a study [40] on inpatients with COVID-19 with a median age of 64 years, the use of dexamethasone reduced all-cause mortality and discharge to hospice care, particularly among patients requiring oxygen support, MV, or ECMO. Furthermore, in the absence of contraindications to anticoagulants, the prophylactic dose of heparin [49,50] is recommended.

Vaccination is recommended for older adults, and the Centers for Disease Control and Prevention (CDC) [51] currently endorses the use of the Pfizer, Moderna (Cambridge, MA, USA), and Novavax (Gaithersburg, MD, USA) vaccines. Moreover currently, the Janssen (Beerse, Belgium) vaccine is not in use. In a study [52] involving patients aged ≥70 years, both the Pfizer and AstraZeneca (Cambridge, UK) vaccines demonstrated efficacy in providing protection. Notably, among patients aged ≥80 years, both vaccines reduced the risk of hospitalization. Whereas the Pfizer vaccine was found to decrease the risk of mortality. Moreover, research [53] assessing the effects of vaccination in relation to mortality and deaths associated with COVID-19 in patients aged ≥60 years revealed that most vaccines had a favorable impact on reducing hospitalizations and deaths. Common side effects of vaccines [54] include local and systemic reactions, such as pain at the injection site, fever, fatigue, and headache. Although severe adverse events related to currently available COVID-19 vaccines are extremely rare, they have shown a minor risk of myocarditis [55,56] (more prevalent in younger individuals) and thrombosis with thrombocytopenia [57,58].

Contribute Factors of COVID-19 Severity

Older age has consistently been linked to more severe COVID-19 outcomes. According to a systematic review and meta-analysis [59], there is a correlation between age and severe outcomes of COVID-19, such as hospitalization, intensive care unit admission, MV, and mortality. Furthermore, in most studies, older age was associated with an increased likelihood of progression to severe or critical conditions [16,32,60,61] and a higher fatality rate [28,62].

Consequently, the mortality rate among older patients was notably higher than younger patients [63,64]. This finding reinforces the notion that advanced age is a significant risk factor for COVID-19 [6-9,65-67]. In addition to age, several other recognized risk factors contribute to disease severity and potentially fatal outcomes. Certain comorbidities have also been highlighted as contributing factors to COVID-19 outcomes. Conditions such as diabetes [68-70], hypertension [7,21,70], cardiovascular diseases [20,68,71], chronic kidney disease [70,72] and respiratory illnesses [7,68,73] have been consistently reported as risk multipliers for severe or fatal outcomes. Furthermore, smoking [7], obesity [68,74], and immunosuppressed states [8,74] have shown a tendency to worsen the prognosis. In addition to these comorbidities, laboratory data have provided further insight into the predictors of COVID-19 outcomes. Elevated levels of inflammatory markers such as CRP [28,75,76], D-dimer [7], intereleukin-6 [71], ferritin, and lactate [77] have been consistently associated with poor outcomes. Moreover, decreased lymphocyte counts [20,71], indicating a compromised immune response, have been observed in many more severe cases. Abnormalities in liver [63] and kidney function tests [76,78] may also be associated with poorer outcomes in COVID-19 patients. Additionally, frailty, which is often assessed using frailty scales [79] or indices [80], has emerged as another significant predictor of adverse outcomes in COVID-19 patients [81-84].

Long COVID-19 Syndrome

Long COVID-19 syndrome, often referred to as “Post-COVID conditions” or “Long COVID,” designates a range of symptoms that continue for weeks or months beyond the acute phase of a COVID-19 infection or appear after the infection has resolved (Table 1). The array of symptoms associated with long-term COVID-19 syndrome is broad, encompassing both physical and neuropsychiatric manifestations. The commonly reported symptoms are shown in Table 1 [85-94]. Management of long-term COVID-19 is currently symptomatic and supportive. Furthermore, given the diverse symptom presentations, a multidisciplinary approach is often required.

Long COVID-19 syndrome

Older patients exhibit a heightened risk of persistent symptoms following COVID-19 [85] as well as the potential exacerbation of chronic conditions [95]. Notably, COVID-19 vaccinations have been suggested to reduce the incidence of long COVID-19 [86,95]. However, given that this syndrome can exacerbate a patient’s frailty, early multidisciplinary interventions [87] coupled with effective symptom management are crucial for older patients [95]. In a study [96] focused on individuals aged ≥65, patients were identified using diagnostic codes corresponding to COVID-19, influenza, and related symptoms. Outpatients with long COVID predominantly exhibited symptoms such as dyspnea, fatigue, palpitations, memory issues, cognitive impairments, sleep disturbances, and loss of taste or smell. The inpatients predominantly experienced dyspnea, fatigue, palpitations, and loss of taste or smell. Based on symptomatology, 16.6% of general patients and 29.2% of inpatients met the criteria for long COVID syndrome, consistent with findings from other studies [88].


Older individuals with COVID-19 exhibit distinct clinical features and face significant prognostic challenges. Therefore, a comprehensive understanding of the clinical profiles and effective management strategies is imperative for healthcare professionals to optimize care and enhance outcomes in this vulnerable population. Moreover, continued research efforts are crucial for refining treatment protocols and preventive measures tailored to older patients.


Authors’ Contributions

Conceptualization: Lee JE, Lee SI. Methodology: Lee SI. Formal analysis: Lee SI. Data curation: all authors. Validation: Lee JE, Lee SI. Investigation: Lee JE, Lee SI. Writing - original draft preparation: Lee JE, Lee SI. Writing - review and editing: all authors. Approval of final manuscript: all authors.

Conflicts of Interest

No potential conflict of interest relevant to this article was reported.


1. Hu B, Guo H, Zhou P, Shi ZL. Characteristics of SARSCoV-2 and COVID-19. Nat Rev Microbiol 2021;19:141–54.
2. World Health Organization. WHO coronavirus (COVID-19) dashboard [Internet]. Geneva: WHO; 2024 [cited 2024 Feb 21]. Available from:
3. Krishnan A, Hamilton JP, Alqahtani SA, Woreta TA. COVID-19: an overview and a clinical update. World J Clin Cases 2021;9:8–23.
4. Booth A, Reed AB, Ponzo S, Yassaee A, Aral M, Plans D, et al. Population risk factors for severe disease and mortality in COVID-19: a global systematic review and meta-analysis. PLoS One 2021;16e0247461.
5. Lim ZJ, Subramaniam A, Ponnapa Reddy M, Blecher G, Kadam U, Afroz A, et al. Case fatality rates for patients with COVID-19 requiring invasive mechanical ventilation: a meta-analysis. Am J Respir Crit Care Med 2021;203:54–66.
6. Ho FK, Petermann-Rocha F, Gray SR, Jani BD, Katikireddi SV, Niedzwiedz CL, et al. Is older age associated with COVID-19 mortality in the absence of other risk factors?: general population cohort study of 470,034 participants. PLoS One 2020;15e0241824.
7. Dessie ZG, Zewotir T. Mortality-related risk factors of COVID-19: a systematic review and meta-analysis of 42 studies and 423,117 patients. BMC Infect Dis 2021;21:855.
8. Kim L, Garg S, O’Halloran A, Whitaker M, Pham H, Anderson EJ, et al. Risk factors for intensive care unit admission and in-hospital mortality among hospitalized adults identified through the US coronavirus disease 2019 (COVID-19)-associated hospitalization surveillance network (COVID-NET). Clin Infect Dis 2021;72:e206–14.
9. Li X, Xu S, Yu M, Wang K, Tao Y, Zhou Y, et al. Risk factors for severity and mortality in adult COVID-19 inpatients in Wuhan. J Allergy Clin Immunol 2020;146:110–8.
10. World Health Organization. WHO coronavirus (COVID-19) dashboard of Republic of Korea [Internet]. Geneva: WHO; 2024 [cited 2024 Feb 21]. Available from:
11. Korea Centers for Disease Control & Prevention. Domestic occurrence status of COVID-19 [Internet]. Cheongju: KCDC; 2023 [cited 2024 Feb 21]. Available from:
12. Lithander FE, Neumann S, Tenison E, Lloyd K, Welsh TJ, Rodrigues JC, et al. COVID-19 in older people: a rapid clinical review. Age Ageing 2020;49:501–15.
13. Li P, Chen L, Liu Z, Pan J, Zhou D, Wang H, et al. Clinical features and short-term outcomes of elderly patients with COVID-19. Int J Infect Dis 2020;97:245–50.
14. Singhal S, Kumar P, Singh S, Saha S, Dey AB. Clinical features and outcomes of COVID-19 in older adults: a systematic review and meta-analysis. BMC Geriatr 2021;21:321.
15. Niu S, Tian S, Lou J, Kang X, Zhang L, Lian H, et al. Clinical characteristics of older patients infected with COVID-19: a descriptive study. Arch Gerontol Geriatr 2020;89:104058.
16. Luo H, Liu S, Wang Y, Phillips-Howard PA, Ju S, Yang Y, et al. Age differences in clinical features and outcomes in patients with COVID-19, Jiangsu, China: a retrospective, multicentre cohort study. BMJ Open 2020;10e039887.
17. Barnett K, Mercer SW, Norbury M, Watt G, Wyke S, Guthrie B. Epidemiology of multimorbidity and implications for health care, research, and medical education: a cross-sectional study. Lancet 2012;380:37–43.
18. Lee TW, Chung J, Song K, Kim E. Incidence and predictors of multimorbidity among older adults in Korea: a 10-year cohort study. BMC Geriatr 2022;22:565.
19. Seong GM, Baek AR, Baek MS, Kim WY, Kim JH, Lee BY, et al. Comparison of clinical characteristics and outcomes of younger and elderly patients with severe COVID-19 in Korea: a retrospective multicenter study. J Pers Med 2021;11:1258.
20. Wei C, Liu Y, Liu Y, Zhang K, Su D, Zhong M, et al. Clinical characteristics and manifestations in older patients with COVID-19. BMC Geriatr 2020;20:395.
21. Ibrahim ME, Al-Aklobi OS, Abomughaid MM, Al-Ghamdi MA. Epidemiological, clinical, and laboratory findings for patients of different age groups with confirmed coronavirus disease 2019 (COVID-19) in a hospital in Saudi Arabia. PLoS One 2021;16e0250955.
22. Liu X, Lv J, Gan L, Zhang Y, Sun F, Meng B, et al. Comparative analysis of clinical characteristics, imaging and laboratory findings of different age groups with COVID-19. Indian J Med Microbiol 2020;38:87–93.
23. Martinez Chamorro E, Diez Tascon A, Ibanez Sanz L, Ossaba Velez S, Borruel Nacenta S. Radiologic diagnosis of patients with COVID-19. Radiologia (Engl Ed) 2021;63:56–73.
24. Statsenko Y, Al Zahmi F, Habuza T, Almansoori TM, Smetanina D, Simiyu GL, et al. Impact of age and sex on COVID-19 severity assessed from radiologic and clinical findings. Front Cell Infect Microbiol 2022;11:777070.
25. Sano T, Kimizuka Y, Fujikura Y, Hisada T, Watanabe C, Suematsu R, et al. COVID-19 in older adults: retrospective cohort study in a tertiary hospital in Japan. Geriatr Gerontol Int 2020;20:1044–9.
26. Guo T, Shen Q, Guo W, He W, Li J, Zhang Y, et al. Clinical characteristics of elderly patients with COVID-19 in Hunan Province, China: a multicenter, retrospective study. Gerontology 2020;66:467–75.
27. Geng MJ, Wang LP, Ren X, Yu JX, Chang ZR, Zheng CJ, et al. Risk factors for developing severe COVID-19 in China: an analysis of disease surveillance data. Infect Dis Poverty 2021;10:48.
28. Lee JY, Kim HA, Huh K, Hyun M, Rhee JY, Jang S, et al. Risk factors for mortality and respiratory support in elderly patients hospitalized with COVID-19 in Korea. J Korean Med Sci 2020;35e223.
29. Briciu V, Topan A, Calin M, Dobrota R, Leucuta DC, Lupse M. Comparison of COVID-19 severity in vaccinated and unvaccinated patients during the Delta and Omicron wave of the pandemic in a Romanian tertiary infectious diseases hospital. Healthcare (Basel) 2023;11:373.
30. Lauring AS, Tenforde MW, Chappell JD, Gaglani M, Ginde AA, McNeal T, et al. Clinical severity of, and effectiveness of mRNA vaccines against, COVID-19 from omicron, delta, and alpha SARS-CoV-2 variants in the United States: prospective observational study. BMJ 2022;376e069761.
31. Wynants L, Van Calster B, Collins GS, Riley RD, Heinze G, Schuit E, et al. Prediction models for diagnosis and prognosis of COVID-19: systematic review and critical appraisal. BMJ 2020;369:m1328.
32. Wu Z, McGoogan JM. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: summary of a report of 72 314 cases from the Chinese Center for Disease Control and Prevention. JAMA 2020;323:1239–42.
33. Williamson EJ, Walker AJ, Bhaskaran K, Bacon S, Bates C, Morton CE, et al. Factors associated with COVID-19-related death using OpenSAFELY. Nature 2020;584:430–6.
34. National Institutes of Health. Coronavirus disease 2019 (COVID-19) treatment guidelines [Internet]. Bethesda: NIH; 2024 [cited 2024 Feb 21]. Available from:
35. Ma BH, Yip TC, Lui GC, Lai MS, Hui E, Wong VW, et al. Clinical outcomes following treatment for COVID-19 with nirmatrelvir/ritonavir and molnupiravir among patients living in nursing homes. JAMA Netw Open 2023;6e2310887.
36. Hammond J, Leister-Tebbe H, Gardner A, Abreu P, Bao W, Wisemandle W, et al. Oral nirmatrelvir for high-risk, nonhospitalized adults with COVID-19. N Engl J Med 2022;386:1397–408.
37. Najjar-Debbiny R, Gronich N, Weber G, Khoury J, Amar M, Stein N, et al. Effectiveness of paxlovid in reducing severe coronavirus disease 2019 and mortality in high-risk patients. Clin Infect Dis 2023;76:e342–9.
38. Gottlieb RL, Vaca CE, Paredes R, Mera J, Webb BJ, Perez G, et al. Early remdesivir to prevent progression to severe COVID-19 in outpatients. N Engl J Med 2022;386:305–15.
39. Basoulis D, Tsakanikas A, Gkoufa A, Bitsani A, Karamanakos G, Mastrogianni E, et al. Effectiveness of oral nirmatrelvir/ritonavir vs. intravenous three-day remdesivir in preventing progression to severe COVID-19: a single-center, prospective, comparative, real-life study. Viruses 2023;15:1515.
40. Mourad A, Thibault D, Holland TL, Yang S, Young AR, Arnold Egloff SA, et al. Dexamethasone for inpatients with COVID-19 in a national cohort. JAMA Netw Open 2023;6e238516.
41. Grundeis F, Ansems K, Dahms K, Thieme V, Metzendorf MI, Skoetz N, et al. Remdesivir for the treatment of COVID-19. Cochrane Database Syst Rev 2023;1:CD014962.
42. Margalit I, Tiseo G, Ripa M, Borghi V, Green H, Prendki V, et al. Real-life experience with remdesivir for treatment of COVID-19 among older adults: a multicentre retrospective study. J Antimicrob Chemother 2023;78:1505–9.
43. RECOVERY Collaborative Group, Horby P, Lim WS, Emberson JR, Mafham M, Bell JL, et al. Dexamethasone in hospitalized patients with COVID-19. N Engl J Med 2021;384:693–704.
44. RECOVERY Collaborative Group. Baricitinib in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial and updated meta-analysis. Lancet 2022;400:359–68.
45. Kalil AC, Patterson TF, Mehta AK, Tomashek KM, Wolfe CR, Ghazaryan V, et al. Baricitinib plus remdesivir for hospitalized adults with COVID-19. N Engl J Med 2021;384:795–807.
46. Kyriakopoulos C, Ntritsos G, Gogali A, Milionis H, Evangelou E, Kostikas K. Tocilizumab administration for the treatment of hospitalized patients with COVID-19: a systematic review and meta-analysis. Respirology 2021;26:1027–40.
47. Abizanda P, Calbo Mayo JM, Mas Romero M, Cortes Zamora EB, Tabernero Sahuquillo MT, Romero Rizos L, et al. Baricitinib reduces 30-day mortality in older adults with moderate-to-severe COVID-19 pneumonia. J Am Geriatr Soc 2021;69:2752–8.
48. Korayem GB, Aljuhani O, Altebainawi AF, Shaya AI, Alnajjar LI, Alissa A, et al. The safety and effectiveness of tocilizumab in older adult critically ill patients with COVID-19: a multicenter, cohort study. Int J Infect Dis 2022;122:252–9.
49. Schulman S, Sholzberg M, Spyropoulos AC, Zarychanski R, Resnick HE, Bradbury CA, et al. ISTH guidelines for antithrombotic treatment in COVID-19. J Thromb Haemost 2022;20:2214–25.
50. Cuker A, Tseng EK, Schunemann HJ, Angchaisuksiri P, Blair C, Dane K, et al. American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis for patients with COVID-19: March 2022 update on the use of anticoagulation in critically ill patients. Blood Adv 2022;6:4975–82.
51. Centers for Disease Control and Prevention. Overview of COVID-19 vaccines [Internet]. Atlanta: CDC; 2024 [cited 2024 Feb 21]. Available from:
52. Lopez Bernal J, Andrews N, Gower C, Robertson C, Stowe J, Tessier E, et al. Effectiveness of the Pfizer-BioNTech and Oxford-AstraZeneca vaccines on COVID-19 related symptoms, hospital admissions, and mortality in older adults in England: test negative case-control study. BMJ 2021;373:n1088.
53. Arregoces-Castillo L, Fernandez-Nino J, Rojas-Botero M, Palacios-Clavijo A, Galvis-Pedraza M, Rincon-Medrano L, et al. Effectiveness of COVID-19 vaccines in older adults in Colombia: a retrospective, population-based study of the ESPERANZA cohort. Lancet Healthy Longev 2022;3e242. –52.
54. Medeiros KS, Costa AP, Sarmento AC, Freitas CL, Goncalves AK. Side effects of COVID-19 vaccines: a systematic review and meta-analysis protocol of randomised trials. BMJ Open 2022;12e050278.
55. Rosenblum HG, Hadler SC, Moulia D, Shimabukuro TT, Su JR, Tepper NK, et al. Use of COVID-19 vaccines after reports of adverse events among adult recipients of Janssen (Johnson & Johnson) and mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna): update from the Advisory Committee on Immunization Practices: United States, July 2021. MMWR Morb Mortal Wkly Rep 2021;70:1094–9.
56. Gargano JW, Wallace M, Hadler SC, Langley G, Su JR, Oster ME, et al. Use of mRNA COVID-19 vaccine after reports of myocarditis among vaccine recipients: update from the Advisory Committee on Immunization Practices: United States, June 2021. MMWR Morb Mortal Wkly Rep 2021;70:977–82.
57. Yamamoto K. Adverse effects of COVID-19 vaccines and measures to prevent them. Virol J 2022;19:100.
58. Warkentin TE, Pai M. The epidemiology of thrombosis with thrombocytopenia syndrome: analogies with heparin-induced thrombocytopenia. Ann Intern Med 2022;175:604–5.
59. Romero Starke K, Reissig D, Petereit-Haack G, Schmauder S, Nienhaus A, Seidler A. The isolated effect of age on the risk of COVID-19 severe outcomes: a systematic review with meta-analysis. BMJ Glob Health 2021;6e006434.
60. CDC COVID-19 Response Team. Severe outcomes among patients with coronavirus disease 2019 (COVID-19): United States, February 12-March 16, 2020. MMWR Morb Mortal Wkly Rep 2020;69:343–6.
61. Yanez ND, Weiss NS, Romand JA, Treggiari MM. COVID-19 mortality risk for older men and women. BMC Public Health 2020;20:1742.
62. Casas-Deza D, Bernal-Monterde V, Aranda-Alonso AN, Montil-Miguel E, Julian-Gomara AB, Letona-Gimenez L, et al. Age-related mortality in 61,993 confirmed COVID-19 cases over three epidemic waves in Aragon, Spain. Implications for vaccination programmes. PLoS One 2021;16e0261061.
63. Gupta S, Hayek SS, Wang W, Chan L, Mathews KS, Melamed ML, et al. Factors associated with death in critically ill patients with coronavirus disease 2019 in the US. JAMA Intern Med 2020;180:1436–47.
64. Harris E. Most COVID-19 deaths worldwide were among older people. JAMA 2023;329:704.
65. Grasselli G, Greco M, Zanella A, Albano G, Antonelli M, Bellani G, et al. Risk factors associated with mortality among patients with COVID-19 in intensive care units in Lombardy, Italy. JAMA Intern Med 2020;180:1345–55.
66. Malhotra V, Basu S, Sharma N, Kumar S, Garg S, Dushyant K, et al. Outcomes among 10,314 hospitalized COVID-19 patients at a tertiary care government hospital in Delhi, India. J Med Virol 2021;93:4553–8.
67. Hoffmann C, Wolf E. Older age groups and country-specific case fatality rates of COVID-19 in Europe, USA and Canada. Infection 2021;49:111–6.
68. Kragholm K, Andersen MP, Gerds TA, Butt JH, Ostergaard L, Polcwiartek C, et al. Association between male sex and outcomes of coronavirus disease 2019 (COVID-19): a Danish nationwide, register-based study. Clin Infect Dis 2021;73:e4025–30.
69. Mayerhöfer T, Klein S, Wernly B, Flaatten H, Guidet B, De Lange DW, et al. Diabetes mellitus is associated with 90-day mortality in old critically ill COVID-19 patients: a multicenter prospective observational cohort study. Infection 2023;51:1407–15.
70. Alves VP, Casemiro FG, Araujo BG, Lima MA, Oliveira RS, Fernandes FT, et al. Factors associated with mortality among elderly people in the COVID-19 pandemic (SARSCoV-2): a systematic review and meta-analysis. Int J Environ Res Public Health 2021;18:8008.
71. Trecarichi EM, Mazzitelli M, Serapide F, Pelle MC, Tassone B, Arrighi E, et al. Clinical characteristics and predictors of mortality associated with COVID-19 in elderly patients from a long-term care facility. Sci Rep 2020;10:20834.
72. Berenguer J, Borobia AM, Ryan P, Rodriguez-Bano J, Bellon JM, Jarrin I, et al. Development and validation of a prediction model for 30-day mortality in hospitalised patients with COVID-19: the COVID-19 SEIMC score. Thorax 2021;76:920–9.
73. Wang L, He W, Yu X, Hu D, Bao M, Liu H, et al. Coronavirus disease 2019 in elderly patients: characteristics and prognostic factors based on 4-week follow-up. J Infect 2020;80:639–45.
74. COVID-ICU Group on behalf of the REVA Network and the COVID-ICU Investigators. Clinical characteristics and day-90 outcomes of 4244 critically ill adults with COVID-19: a prospective cohort study. Intensive Care Med 2021;47:60–73.
75. Liu K, Chen Y, Lin R, Han K. Clinical features of COVID-19 in elderly patients: a comparison with young and middle-aged patients. J Infect 2020;80:e14–8.
76. Gao S, Jiang F, Jin W, Shi Y, Yang L, Xia Y, et al. Risk factors influencing the prognosis of elderly patients infected with COVID-19: a clinical retrospective study in Wuhan, China. Aging (Albany NY) 2020;12:12504–16.
77. Bruno RR, Wernly B, Flaatten H, Fjolner J, Artigas A, Bollen Pinto B, et al. Lactate is associated with mortality in very old intensive care patients suffering from COVID-19: results from an international observational study of 2860 patients. Ann Intensive Care 2021;11:128.
78. Bavaro DF, Diella L, Fabrizio C, Sulpasso R, Bottalico IF, Calamo A, et al. Peculiar clinical presentation of COVID-19 and predictors of mortality in the elderly: a multicentre retrospective cohort study. Int J Infect Dis 2021;105:709–15.
79. Ko RE, Moon SM, Kang D, Cho J, Chung CR, Lee Y, et al. Translation and validation of the Korean version of the clinical frailty scale in older patients. BMC Geriatr 2021;21:47.
80. Quan H, Li B, Couris CM, Fushimi K, Graham P, Hider P, et al. Updating and validating the Charlson comorbidity index and score for risk adjustment in hospital discharge abstracts using data from 6 countries. Am J Epidemiol 2011;173:676–82.
81. Aw D, Woodrow L, Ogliari G, Harwood R. Association of frailty with mortality in older inpatients with COVID-19: a cohort study. Age Ageing 2020;49:915–22.
82. Pranata R, Henrina J, Lim MA, Lawrensia S, Yonas E, Vania R, et al. Clinical frailty scale and mortality in COVID-19: a systematic review and dose-response meta-analysis. Arch Gerontol Geriatr 2021;93:104324.
83. Owen RK, Conroy SP, Taub N, Jones W, Bryden D, Pareek M, et al. Comparing associations between frailty and mortality in hospitalised older adults with or without COVID-19 infection: a retrospective observational study using electronic health records. Age Ageing 2021;50:307–16.
84. Jung C, Flaatten H, Fjolner J, Bruno RR, Wernly B, Artigas A, et al. The impact of frailty on survival in elderly intensive care patients with COVID-19: the COVIP study. Crit Care 2021;25:149.
85. Kim Y, Kim SW, Chang HH, Kwon KT, Bae S, et al. Post-acute COVID-19 syndrome in patients after 12 months from COVID-19 infection in Korea. BMC Infect Dis 2022;22:93.
86. Korea Disease Control and Prevention Agency. COVID-19, long COVID [Internet]. Cheongju: KDCA; 2023. [cited 2024 Feb 21]. Available from:
87. Parker AM, Brigham E, Connolly B, McPeake J, Agranovich AV, Kenes MT, et al. Addressing the post-acute sequelae of SARS-CoV-2 infection: a multidisciplinary model of care. Lancet Respir Med 2021;9:1328–41.
88. Global Burden of Disease Long COVID Collaborators, Wulf Hanson S, Abbafati C, Aerts JG, Al-Aly Z, Ashbaugh C, et al. Estimated global proportions of individuals with persistent fatigue, cognitive, and respiratory symptom clusters following symptomatic COVID-19 in 2020 and 2021. JAMA 2022;328:1604–15.
89. Centers for Disease Control and Prevention. Post-COVID conditions: information for healthcare providers [Internet]. Atlanta: CDC; 2024. [cited 2024 Feb 21]. Available from:
90. Yelin D, Moschopoulos CD, Margalit I, Gkrania-Klotsas E, Landi F, Stahl JP, et al. ESCMID rapid guidelines for assessment and management of long COVID. Clin Microbiol Infect 2022;28:955–72.
91. Halpin S, O’Connor R, Sivan M. Long COVID and chronic COVID syndromes. J Med Virol 2021;93:1242–3.
92. Soriano JB, Murthy S, Marshall JC, Relan P, Diaz JV, ; WHO Clinical Case Definition Working Group on Post-COVID-19 Condition. A clinical case definition of post-COVID-19 condition by a Delphi consensus. Lancet Infect Dis 2022;22:e102–7.
93. COVID-19 rapid guideline: managing the long-term effects of COVID-19. London: National Institute for Health and Care Excellence (NICE); 2020.
94. Greenhalgh T, Knight M, A’Court C, Buxton M, Husain L. Management of post-acute COVID-19 in primary care. BMJ 2020;370:m3026.
95. Mansell V, Hall Dykgraaf S, Kidd M, Goodyear-Smith F. Long COVID and older people. Lancet Healthy Longev 2022;3:e849–54.
96. Fung KW, Baye F, Baik SH, Zheng Z, McDonald CJ. Prevalence and characteristics of long COVID in elderly patients: an observational cohort study of over 2 million adults in the US. PLoS Med 2023;20e1004194.

Article information Continued

Fig. 1.

Radiologic findings of older patients with coronavirus disease 2019 (COVID-19). (A, B) Normal lung on radiography and computed tomography (CT), (C, D) ground-glass opacities on chest X-ray and CT, (E, F) consolidation on chest Xray and CT, and (G, H) fibrosis on chest X-ray and CT. L: left; R: right; PA: posterior anterior; AP: anterior posterior.

Fig. 2.

Treatment of older patients with COVID-19[34]. SARS-CoV-2: severe acute respiratory syndrome coronavirus-2; PO: per oral; IV: intravenous; HFNC: high-flow nasal cannula; NIV: non-invasive ventilation; MV: mechanical ventilation; ECMO: extracorporeal membrane oxygenation.

Table 1.

Long COVID-19 syndrome

Title Contents
Several other terms - Post-acute sequelae of severe acute respiratory syndrome coronavirus 2 infection [87] (PASC)
- Long COVID [89-91]
- Post-COVID syndrome [89,92,93]
- Chronic COVID-19 [91]
- Post-acute COVID-19 [94]
Description A range of symptoms that continue for weeks or months after the acute phase of a COVID-19 infection has resolved.
Definition [86] - World Health Organization (WHO) [92]: Defines “Post-COVID conditions” as symptoms that appear typically within 3 months after the onset of COVID-19 symptoms and persist for at least 2 months, which cannot be explained by an alternative diagnosis.
- U.S. Centers for Disease Control and Prevention (CDC) [89]: Defines “Post-COVID conditions” (also referred to as “Long COVID”) as instances where symptoms continue 4 weeks or more following a COVID-19 infection.
- National Institute for Health and Care Excellence (NICE), UK [93]: Defines “Ongoing symptomatic COVID-19” as COVID-19 symptoms persisting between 4 and 12 weeks. For symptoms continuing after 12 weeks post-diagnosis of COVID-19 that cannot be explained by another diagnosis, they use the term “Post-COVID syndrome.”
- European Society of Clinical Microbiology and Infectious Diseases (ESCMID) [90]: Defines “Long COVID” as symptoms or signs persisting or recurring after 12 weeks from the diagnosis of COVID-19 that cannot be explained by an alternative diagnosis.
- Korea Disease Control and Prevention Agency (KDCA) and Korean Society of Infectious Diseases [86]: Define it as one or more symptoms/signs persisting after 12 weeks from the COVID-19 diagnosis that cannot be attributed to other diseases.
Common symptoms [85,88-90] - Fatigue
- Breathlessness
- Joint pain
- Chest pain
- Memory and concentration issues (brain fog)
- Sleep disorders
- Loss of taste and smell
- Persistent cough
Management and treatment [89,90,94] - Symptomatic treatment
- Physical therapy
- Occupational therapy
- Mental health support

COVID-19: coronavirus disease 2019.