Vol 6, No 3 (2021)
Original article
Published online: 2021-09-07

open access

Page views 6619
Article views/downloads 538
Get Citation

Connect on Social Media

Connect on Social Media

Study on the utility and efficacy of clinical and instrumental tests in the follow-up of COVID-19 patients

Alberto Preda1, Giorgio Fiore1, Carlo Gaspardone1, Silvana Di Maio1, Davide Romagnolo1, Lorenzo Rampa1, Luigia Brugliera2, Andrea Tettamanti2, Carlo Meloni2, Sandro Iannaccone2
Medical Research Journal 2021;6(3):169-176.


Introduction: The disease caused by the SARS-CoV-2 virus (COVID-19) frequently leads to serious complications and prolonged hospitalizations requiring effective care after discharge.

Aim of the study: Aim of this study was to identify feasible and cost-effective predictors of outcome among clinical characteristics, functional status, laboratory, echocardiographic and lung ultrasound data of COVID-19 patients.

Material and methods: Patients affected by COVID-19 who experienced a prolonged hospitalization due to a severe form of the disease and that have been discharged from the COVID-19 rehabilitation unit (RU) were prospectively enrolled between April 6th and May 22nd, 2020. All the patients underwent a 6-minute walk test (6MWT) at the 30-day follow-up. Baseline characteristics, laboratory, functional exercise tests, echocardiographic and lung ultrasound (LUS) data collected between hospitalization, admission to RU, discharge from RU and follow-up were compared. Correlations with the predicted distance covered at the 6MWT (6MWD) were made.

Results: 40 patients met inclusion criteria and presented to follow-up (13 women [32.5%] and 27 men [67.5%]; mean age 66 ± 10 years). Among all variables analysed, only functional tests at discharge showed a remarkable correlation with the 6MWD. Significant improvement in lung ultrasound score (LUSS) was also observed however without correlation with 6MWD.

Conclusions: functional tests at discharge from RU identified patients with different 30-day outcomes that could deserve a stricter long-term follow-up. This may help in planning a personalized follow-up. The costs and effort were minimal. The severity of the acute phase did not significantly influence functional recovery. LUS was useful to identify subclinical lung damage and its evolution over time, however without clear functional correlation.

Article available in PDF format

View PDF Download PDF file


  1. Huang C, Wang Y, Li X, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet. 2020; 395(10223): 497–506.
  2. Marshall M. The lasting misery of coronavirus long-haulers. Nature. 2020; 585(7825): 339–341.
  3. Rees EM, Nightingale ES, Jafari Y, et al. COVID-19 length of hospital stay: a systematic review and data synthesis. BMC Med. 2020; 18(1): 270.
  4. Iannaccone S, Castellazzi P, Tettamanti A, et al. Role of rehabilitation department for adult individuals with COVID-19: The experience of the San Raffaele Hospital of Milan. Arch Phys Med Rehabil. 2020; 101(9): 1656–1661.
  5. Wade DT. Rehabilitation after COVID-19: an evidence-based approach. Clin Med (Lond). 2020; 20(4): 359–365.
  6. Brugliera L, Spina A, Castellazzi P, et al. Rehabilitation of COVID-19 patients. J Rehabil Med. 2020; 52(4): jrm00046.
  7. Negrini F, de Sire A, Andrenelli E, et al. International Multiprofessional Steering Committee of Cochrane Rehabilitation REH-COVER action. Rehabilitation and COVID-19: a rapid living systematic review 2020 by Cochrane Rehabilitation Field. Update as of October 31st, 2020. Eur J Phys Rehabil Med. 2021; 57(1): 166–170.
  8. Balachandar V, Mahalaxmi I, Subramaniam M, et al. Follow-up studies in COVID-19 recovered patients - is it mandatory? Sci Total Environ. 2020; 729: 139021.
  9. Taboada M, Cariñena A, Moreno E, et al. Post-COVID-19 functional status six-months after hospitalization. J Infect. 2021; 82(4): e31–e33.
  10. Cortinovis M, Perico N, Remuzzi G. Long-term follow-up of recovered patients with COVID-19. Lancet. 2021; 397(10270): 173–175.
  11. Du RH, Liang LR, Yang CQ, et al. Predictors of mortality for patients with COVID-19 pneumonia caused by SARS-CoV-2: a prospective cohort study. Eur Respir J. 2020; 55(5).
  12. Ai T, Yang Z, Hou H, et al. Correlation of chest CT and RT-PCR testing for Coronavirus Disease 2019 (COVID-19) in China: A report of 1014 cases. Radiology. 2020; 296(2): E32–E40.
  13. Lanza E, Profili M, Bolengo I, et al. COVID-19 lung alterations still evident at 60-day follow-up chest CT in asymptomatic patients despite negative rRT-PCR testing. 2020.
  14. Tabata S, Imai K, Kawano S, et al. Clinical characteristics of COVID-19 in 104 people with SARS-CoV-2 infection on the Diamond Princess cruise ship: a retrospective analysis. Lancet Infect Dis. 2020; 20(9): 1043–1050.
  15. Peng QY, Wang XT, Zhang LN, et al. Chinese Critical Care Ultrasound Study Group (CCUSG). Findings of lung ultrasonography of novel corona virus pneumonia during the 2019-2020 epidemic. Intensive Care Med. 2020; 46(5): 849–850.
  16. Soldati G, Smargiassi A, Inchingolo R, et al. Is there a role for lung ultrasound during the COVID-19 pandemic? J Ultrasound Med. 2020; 39(7): 1459–1462.
  17. Gaspardone C, Meloni C, Preda A, et al. Lung ultrasound in COVID-19 a role beyond the acute phase? J Ultrasound Med. 2021; 40(3): 503–511.
  18. Giannitsi S, Bougiakli M, Bechlioulis A, et al. 6-minute walking test: a useful tool in the management of heart failure patients. Ther Adv Cardiovasc Dis. 2019; 13: 1753944719870084.
  19. Dajczman E, Wardini R, Kasymjanova G, et al. Six minute walk distance is a predictor of survival in patients with chronic obstructive pulmonary disease undergoing pulmonary rehabilitation. Can Respir J. 2015; 22(4): 225–229.
  20. Rasekaba T, Lee AL, Naughton MT, et al. The six-minute walk test: a useful metric for the cardiopulmonary patient. Intern Med J. 2009; 39(8): 495–501.
  21. Podsiadlo D, Richardson S. The timed "Up & Go": a test of basic functional mobility for frail elderly persons. J Am Geriatr Soc. 1991; 39(2): 142–148.
  22. Mesquita R, Wilke S, Smid DE, et al. Measurement properties of the Timed Up & Go test in patients with COPD. Chron Respir Dis. 2016; 13(4): 344–352.
  23. Vaidya T, Chambellan A, de Bisschop C. Sit-to-stand tests for COPD: A literature review. Respir Med. 2017; 128: 70–77.
  24. Kidd D, Stewart G, Baldry J, et al. The Functional Independence Measure: a comparative validity and reliability study. Disabil Rehabil. 1995; 17(1): 10–14.
  25. Gillen G. Overview of Cognitive and Perceptual Rehabilitation. Cognitive and Perceptual Rehabilitation. 2009: 1–31.
  26. Sasanuma N, Takahashi K, Tanaka T, et al. Functional independence measure analysis in patients undergoing phase I of cardiac rehabilitation. European Heart Journal. 2013; 34(suppl 1): P5801–P5801.
  27. Pandit R, Vaity C, Mulakavalupil B, et al. Unmasking Hypoxia in COVID 19 - Six Minute Walk Test. J Assoc Physicians India. 2020; 68(9): 50–51.
  28. Fuglebjerg NJ, Jensen TO, Hoyer N, et al. Silent hypoxia in patients with SARS CoV-2 infection before hospital discharge. Int J Infect Dis. 2020; 99: 100–101.
  29. Huang C, Huang L, Wang Y, et al. 6-month consequences of COVID-19 in patients discharged from hospital: a cohort study. Lancet. 2021; 397(10270): 220–232.
  30. Terpos E, Ntanasis-Stathopoulos I, Elalamy I, et al. Hematological findings and complications of COVID-19. Am J Hematol. 2020; 95(7): 834–847.
  31. Guo T, Fan Y, Chen M, et al. Cardiovascular implications of fatal outcomes of patients with coronavirus disease 2019 (COVID-19). JAMA Cardiol. 2020; 5(7): 811–818.
  32. Zangrillo A, Beretta L, Scandroglio AM, et al. COVID-BioB Study Group , COVID-BioB Study Group. Characteristics, treatment, outcomes and cause of death of invasively ventilated patients with COVID-19 ARDS in Milan, Italy. Crit Care Resusc. 2020 [Epub ahead of print]; 22(3).
  33. Szekely Y, Lichter Y, Topilsky Y, et al. Spectrum of cardiac manifestations in COVID-19: A systematic echocardiographic study. Circulation. 2020; 142(4): 342–353.
  34. Mongodi S, Bouhemad B, Orlando A, et al. Modified lung ultrasound score for assessing and monitoring pulmonary aeration. Ultraschall Med. 2017; 38(5): 530–537.
  35. Bouhemad B, Mongodi S, Via G, et al. Ultrasound for "lung monitoring" of ventilated patients. Anesthesiology. 2015; 122(2): 437–447.
  36. ATS Committee on Proficiency Standards for Clinical Pulmonary Function Laboratories. ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med. 2002; 166(1): 111–117.
  37. Enright PL, Sherrill DL. Reference equations for the six-minute walk in healthy adults. Am J Respir Crit Care Med. 1998; 158(5 Pt 1): 1384–1387.
  38. Alemanno F, Houdayer E, Parma A, et al. COVID-19 cognitive deficits after respiratory assistance in the subacute phase: A COVID-rehabilitation unit experience. PLoS One. 2021; 16(2): e0246590.