Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2022 Aug 1;113(5):946-959.
doi: 10.1016/j.ijrobp.2022.04.043. Epub 2022 May 7.

Low-Dose Whole Lung Irradiation for Treatment of COVID-19 Pneumonia: A Systematic Review and Meta-Analysis

Kasra Kolahdouzan  1 , Mohammadreza Chavoshi  2 , Reyhaneh Bayani  3 , Nima Mousavi Darzikolaee  4
Affiliations
Meta-Analysis

Low-Dose Whole Lung Irradiation for Treatment of COVID-19 Pneumonia: A Systematic Review and Meta-Analysis

Kasra Kolahdouzan et al. Int J Radiat Oncol Biol Phys. .

Abstract

Purpose: Studies dating back to a century ago have reported using low-dose radiation therapy for the treatment of viral and bacterial pneumonia. In the modern era, since the COVID-19 pandemic began, several groups worldwide have researched the applicability of whole lung irradiation (WLI) for the treatment of COVID-19. We aimed to bring together the results of these experimental studies.

Methods and materials: We performed a systematic review and meta-analysis searching PubMed and Scopus databases for clinical trials incorporating WLI for the treatment of patients with COVID-19. Required data were extracted from each study. Using the random-effects model, the overall pooled day 28 survival rate, survival hazard ratio, and intubation-free days within 15 days after WLI were calculated, and forest plots were produced.

Results: Ten studies were identified, and eventually, 5 were included for meta-analysis. The overall survival hazard ratio was calculated to be 0.85 (0.46-1.57). The pooled mean difference of intubation-free days within 15 days after WLI was 1.87, favoring the WLI group (95% confidence interval, -0.02 to 3.76). The overall day 28 survival rate of patients receiving WLI for the 9 studies with adequate follow-up data was 74% (95% confidence interval, 61-87). Except for 2 studies, the other 8 studies were assessed to have moderate to high risk of bias, and there were many differences among the designs of the studies, included patients, primary endpoints, outcome measurement methods, and reporting of the results.

Conclusions: Despite a mild improvement in intubation-free days, WLI had no significant effect on patients' overall survival. Currently, we cannot recommend routine use of WLI for the treatment of patients with moderate-to-severe COVID-19.

PubMed Disclaimer

Figures

Fig 1
Fig. 1
Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram.
Fig 2
Fig. 2
Risk of bias assessment for overall survival and intubation-free days. The 5 domains of RoB 2 (Cochrane risk-of-bias tool for randomized trials) (top) and the 7 domains of the ROBINS-I (Risk of Bias in Non-randomized Studies - of Interventions) tool (bottom).
Fig 3
Fig. 3
Forest plot depicting pooled overall survival rate on day 28 after whole lung irradiation. Abbreviations: CI = confidence interval; RE = random effects.
Fig 4
Fig. 4
Forest plots for intubation-free days (top) and overall survival hazard ratio (bottom). Abbreviations: CI = confidence interval; IV = weighted mean difference; SD = standard deviation; WLI = whole long irradiation.
See this image and copyright information in PMC

Comment in

  • In Regard to Kolahdouzan et al.
    Li Z, Hu Y, Li Q. Li Z, et al. Int J Radiat Oncol Biol Phys. 2023 Jan 1;115(1):251-252. doi: 10.1016/j.ijrobp.2022.09.051. Int J Radiat Oncol Biol Phys. 2023. PMID: 36526387 Free PMC article. No abstract available.

References

    1. Ruan Q, Yang K, Wang W, Jiang L, Song J. Clinical predictors of mortality due to COVID-19 based on an analysis of data of 150 patients from Wuhan, China. Intensive Care Med. 2020;46:846–848. - PMC - PubMed
    1. Mehta P, McAuley DF, Brown M, et al. COVID-19: Consider cytokine storm syndromes and immunosuppression. Lancet. 2020;395:1033–1034. - PMC - PubMed
    1. Arenas M, Sabater S, Hernandez V, et al. Antiinflammatory effects of low-dose radiation therapy. Indications, dose, and radiobiological mechanisms involved. Strahlenther Onkol. 2012;188:975–981. - PubMed
    1. Rödel F, Kamprad F, Sauer R, Hildebrandt G. Funktionelle und molekulare aspekte der antiinflammatorischen wirkung niedrig dosierter radiotherapie [Functional and molecular aspects of anti-inflammatory effects of low-dose radiotherapy] Strahlenther Onkol. 2002;178:1–9. [in German] - PubMed
    1. Calabrese EJ, Kozumbo WJ, Kapoor R, Dhawan G, Lara PC, Giordano J. Nrf2 activation putatively mediates clinical benefits of low-dose radiation therapy in COVID-19 pneumonia and acute respiratory distress syndrome (ARDS): Novel mechanistic considerations. Radiother Oncol. 2021;160:125–131. - PMC - PubMed