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Meta-Analysis
. 2021 Mar;36(3):343-351.
doi: 10.1177/0885066619885838. Epub 2019 Nov 5.

Six-Minute Walk Distance After Critical Illness: A Systematic Review and Meta-Analysis

Selina M Parry  1 , Swaroopa R Nalamalapu  2 , Krishidhar Nunna  3 , Anahita Rabiee  4 , Lisa Aronson Friedman  5   6 , Elizabeth Colantuoni  5   7 , Dale M Needham  5   6   8 , Victor D Dinglas  5   6
Affiliations
Meta-Analysis

Six-Minute Walk Distance After Critical Illness: A Systematic Review and Meta-Analysis

Selina M Parry et al. J Intensive Care Med. 2021 Mar.

Abstract

Background and objectives: Impaired physical functioning is common and long lasting after an intensive care unit (ICU) admission. The 6-minute walk test (6MWT) is a validated and widely used test of functional capacity. This systematic review synthesizes existing data in order to: (1) evaluate 6-minute walk distance (6MWD) in meters over longitudinal follow-up after critical illness, (2) compare 6MWD between acute respiratory distress syndrome (ARDS) versus non-ARDS survivors, and (3) evaluate patient- and ICU-related factors associated with 6MWD.

Data sources: Five databases (PubMed, EMBASE, Cumulative Index of Nursing and Allied Health Literature, PsychINFO, and Cochrane Controlled Trials Registry) were searched to identify studies reporting 6MWT after hospital discharge in survivors from general (ie, nonspeciality) ICUs. The last search was run on February 14, 2018. Databases were accessed via Johns Hopkins University Library.

Data extraction and synthesis: Pooled mean 6MWD were reported, with separate linear random effects models used to evaluate associations of 6MWD with ARDS status, and patient- and ICU-related variables. Twenty-six eligible articles on 16 unique participant groups were included. The pooled mean (95% confidence interval [CI]) 6MWD results at 3- and 12-months post discharge were 361 (321-401) and 436 (391-481) meters, respectively. There was a significant increase in 6MWD at 12 months compared to 3 months (P = .017). In ARDS versus non-ARDS survivors, the mean (95% CI) 6MWD difference over 3-, 6-, and 12-month follow-up was 73 [13-133] meters lower. Female sex and preexisting comorbidity also were significantly associated with lower 6MWD, with ICU-related variables having no consistent associations.

Conclusions: Compared to initial assessment at 3 months, significant improvement in 6MWD was reported at 12 months. Female sex, preexisting comorbidity, and ARDS (vs non-ARDS) were associated with lower 6MWT results. Such factors warrant consideration in the design of clinical research studies and in the interpretation of patient status using the 6MWT.

Keywords: 6-minute walk test; critical illness; intensive care; physical function; physical recovery.

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Conflict of interest statement

Summary Conflict of Interest statements: No authors had any conflict of interests to declare.

Figures

Figure 1:
Figure 1:. PRISMA flow diagram of study selection process
Abbreviations: CINAHL, Cumulative Index to Nursing and Allied Health Literature; EMBASE, the Excerpta Medica Database.
Figure 2:
Figure 2:. Mean Six minute Walk Distance and 95% Confidence Interval across Months 3-60
Legend Descriptor: This figure demonstrates the pooled mean and 95% CI for 6MWD over 3 - 60 month follow-up for survivors of critical illness. Pooled data at each follow up time-point ranging from 6 - 60 months were compared to the initial assessment at 3 months to determine if there was a significant change. There was a significant increase in 6MWD at 12 and 48 months compared to 3 months (p=0.017, and p=0.028 respectively).
See this image and copyright information in PMC

References

    1. Needham DM, Davidson J, Cohen H, Hopkins RO, Weinert C, Wunsch H, Zawistowski C, Bemis-Dougherty A, Berney SC, Bienvenu OJ, Brady SL, Brodsky MB, Denehy L, Elliott D, Flatley C, Harabin AL, Jones C, Louis D, Meltzer W, Muldoon SR, Palmer JB, Perme C, Robinson M, Schmidt DM, Scruth E, Spill GR, Storey CP, Render M, Votto J, and Harvey MA, Improving long-term outcomes after discharge from intensive care unit: report from a stakeholders’ conference. Crit Care Med, 2012. 40(2): p. 502–9. - PubMed
    1. Herridge MS, Tansey CM, Matte A, Tomlinson G, Diaz-Granados N, Cooper A, Guest CB, Mazer CD, Mehta S, Stewart TE, Kudlow P, Cook D, Slutsky AS, and Cheung AM, Functional disability 5 years after acute respiratory distress syndrome. N Engl J Med, 2011. 364(14): p. 1293–304. - PubMed
    1. Latronico N, Herridge M, Hopkins RO, Angus D, Hart N, Hermans G, Iwashyna T, Arabi Y, Citerio G, Ely EW, Hall J, Mehta S, Puntillo K, Van den Hoeven J, Wunsch H, Cook D, Dos Santos C, Rubenfeld G, Vincent JL, Van den Berghe G, Azoulay E, and Needham DM, The ICM research agenda on intensive care unit-acquired weakness. Intensive Care Med, 2017. 43(9): p. 1270–1281. - PubMed
    1. Chan KS, Pfoh ER, Denehy L, Elliott D, Holland AE, Dinglas VD, and Needham DM, Construct Validity and Minimal Important Difference of 6-Minute Walk Distance in Survivors of Acute Respiratory Failure. Chest, 2015. 147(5): p. 1316–1326. - PMC - PubMed
    1. Moher D, Liberati A, Tetzlaff J, Altman DG, and The PG, Preferred reporting items for systematic reviews and meta-analyses: the PRISMA Statement. Open Medicine, 2009. 3(3): p. e123–e130. - PMC - PubMed

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