. 2018 Dec 19;27(150):180061. doi: 10.1183/16000617.0061-2018

TABLE 3.

Risk factors for overall mortality in patients with mixed-interstitial lung disease (ILD) and idiopathic pulmonary fibrosis (IPF) in the intensive care unit (ICU)

Risk factor	Studies in mixed-ILD patients	Mortality association	Studies in IPF patients	Mortality association
Advanced age	2 positive studies [14, 27], 5 negative studies [12, 18, 22, 26, 28⁺]	Inconclusive: 1 large study in each side	1 positive study [37], 4 negative studies [3, 41, 43^§, 44]	Inconclusive: 1 large study found an association; another large study and four small studies did not
Elevated APACHE score	3 positive studies [12, 14, 18], 3 negative studies [17, 26, 27^ƒ]	Large studies report a significant association	1 positive study [3], 2 negative studies [43^§, 44]	Inconclusive: studies with small sample size
Histology showing diffuse alveolar damage ^#	3 studies [12, 13, 21]	Small studies report high mortality in the univariate analysis; not enough data to assess for an association	3 studies [29, 31, 34]	Small studies report high mortality in the univariate analysis; not enough data to assess for an association
Hypoxaemia	3 positive studies [14, 22^##, 27^¶¶], 1 negative study [18^ƒ]	Large studies report a significant association	3 negative studies [41⁺, 43^§, 44]	No association was found; 2 studies with <20 patients each
Mechanical ventilation ^¶	6 positive studies [12, 14⁺⁺, 17, 18, 26, 27], 2 negative studies [22, 28]	Multiple studies report high mortality in the univariate analysis; 6 studies report a significant association		Multiple studies report high mortality in the univariate analysis; not enough data to assess for an association
Steroids	3 negative studies [14, 26^§§, 28⁺]	No association was found in 3 studies; 1 reported use of steroids was a protective factor	1 negative study [41]	Inconclusive: only 1 study with a small sample size is available

APACHE: Acute Physiology And Chronic Health Evaluation; NIMV: noninvasive mechanical ventilation.^#: no bivariate analysis is provided due to the small sample sizes and high mortality reported in these studies. ^¶: high rates of mortality associated with mechanical ventilation (70–100% for IPF and 27–100% in mixed-ILD) precluded bivariate or multivariate analysis in more studies other than those reported in this table.⁺: an association was found in the bivariate analysis but not in the multivariate. ^§: no direct comparison between survivors and nonsurvivors. The study primary compared NIMV success group versus NIMV failure group. However, no patient died in the former group and all 10 died in the latter group. ^ƒ: a trend towards significance. ^##: this study reported significantly lower arterial oxygen saturation but comparable arterial oxygen tension in nonsurvivors versus survivors (bivariate analysis only). ^¶¶: significantly higher arterial oxygen tension/inspired oxygen fraction ratio in survivors versus nonsurvivors at the start of NIMV but not on admission.⁺⁺: higher positive end-expiratory pressure was associated with increased mortality. ^§§: this study showed that the use of steroids was a protective factor in the multivariate analysis.