Table 1.

Characteristics and Newcastle-Ottawa scale quality score of included studies.

References	Study type	NOS	Country	Number of patients	Period	Mean age, y	Male, (%)	Outcome
Asai et al. (6)	Case-control study	8	Japan	38	2005–2012	NA	NA	30-day mortality
Chen et al. (7)	Case-control study	8	China	69	2004–2013	39	25 (36.23%)	In-hospital mortality
Hardak et al. (8)	Case-control study	8	Israel	58	2005–2010	56	28 (48.3%)	In-hospital mortality
Kageyama et al. (9)	Case-control study	8	Japan	95	2000–2015	69	57 (60%)	In-hospital mortality
Kim et al. (10)	Case-control study	6	Korea	173	2004–2011	56	116(67.05%)	In-hospital mortality
Kim et al. (11)	Cohort study	7	Korea	76	2014–2015	55	53 (65%)	30-day mortality
Ko et al. (12)	Case-control study	8	Korea	51	2005–2018	52	35 (68.6%)	In-hospital mortality
Ko et al. (13)	Case-control study	7	Korea	48	2005–2011	53	33 (69%)	In-hospital mortality
Kofteridis et al. (14)	Cohort study	8	Greece	62	2004–2013	65	43 (69.35%)	In-hospital mortality
Korkmaz et al. (15)	Cohort study	7	Turkey	43	2009–2015	57	30 (69.8%)	30-day mortality
Lemiale et al. (16)	Case-control study	7	France	139	1988–2011	48	79 (56.8%)	ICU mortality
Li et al. (17)	Case-control study	8	Taiwan	20	2008–2011	50	9 (45%)	In-hospital mortality
Liu et al. (18)	Case-control study	8	China	57	2013–2018	48	29 (50.8%)	In-hospital mortality
Matsumura et al. (19)	Case-control study	7	Japan	82	2005–2010	64	51 (62%)	30-day mortality
Roblot et al. (20)	Case-control study	7	France	102	1995–1999	57	61 (59%)	30-day mortality
Tamai et al. (21)	Case-control study	8	Japan	29	2006–2012	59	14 (48%)	In-hospital mortality
Weng et al. (22)	Case-control study	8	China	82	2012–2015	53	34 (41.5%)	In-hospital mortality
Ye et al. (23)	Case-control study	8	China	47	2003–2012	49	21 (44.68%)	30-day mortality
Zahar et al. (24)	Case-control study	8	France	39	1989–1999	48	20 (52.2%)	30-day mortality

ICU, intensive care unit; NA, not available; NOS, Newcastle-Ottawa Scale.