Table 1.

Summary of Studies Exploring Association Between RDW and CVDs

Author, Year	Study Design	Study Population	Major Findings	References
Felker et al, 2007	Retrospective cohort	2679 chronic HF patients	Higher RDW in patient with CV event than without CV events (15.2 vs 14.4). HR for morbidity and mortality (1 SD increment of RDW): 1.17 (95% CI, 1.10–1.25, p<0.001)	[21]
Dai et al, 2014	Cross-sectional study	521 patients with acute HF	Higher RDW (16.2% vs 14.4%) in acute HF patients at admission were associated with worse short- and long-term outcomes and RDW values were more prognostically relevant than Hgb levels	[22]
Jenei et al, 2014	Prospective cohort study	195 patients with stable chronic HF	RDW >14.5% was independent predictor of 5-year mortality (HR 1 SD increment 1.46, 95% CI 1.221–1.733, p<0.001)	[23]
He et al, 2014	Prospective cohort	128 patients with acute HF	Both RDW and NT-proBNP are strong independent predictors of cardiovascular events	[24]
Liu et al, 2016	Retrospective study	179 chronic HF patients	RDW was markedly elevated in the mortality group compared with the survival group (15.8±1.8 vs 13.7±1.7, p<0.01). RDW was an independent risk factor for mortality (OR=2.531, 95% CI: 1.371–4.671) during hospitalization with AUC = 0.837	[25]
Huang et al, 2014	Meta-analysis of 17 studies	18,288 patients with HF	RDW on admission and discharge, as well as its variation during treatment are prognostic markers in HF patients. In particular, each 1% increase in baseline RDW was associated with a 10% increased risk of all-cause mortality (OR, 1.10; 95% CI, 1.07–1.13).	[26]
Cemin et al, 2011	Prospective study	1971 patients admitted due to chest pain of suspected cardiac origin	Higher RDW value was obtained in patient with AMI compared to without AMI (14.4 vs 13.7) and RDW cut-off value of 13.7% showed a sensitivity and specificity of 75% and 52%, respectively	[18]
Hu et al, 2017	Case–control study	100 healthy and 300 patients with coronary heart disease	Stenocardia 121 cases, HF 65 cases and acute MI 114 cases were found. The result revealed that the RDW and HCY were both significantly higher in acute MI groups than in the 3 other groups	[19]
Lippi et al, 2009	Prospective study	2304 adult patients admitted for chest pain suggestive of ACS	The combined measurement of cardiac troponin T and RDW increases diagnostic sensitivity to 99% in diagnosing ACS (diagnostic sensitivity of cardiac troponin T alone was 94%).	[20]
Söderholm et al, 2015	Prospective study	26,879 participants without a history of coronary events or stroke	High RDW was associated with increased incidence of total stroke (HR for stroke 1.31 (1.11–1.54 the highest quartile compared to the lowest)	[29]
Ramírez et al, 2013	Case-control study	224 patients with ischemic stroke and 224 control subjects	Subjects who have RDW >14·61% were more likely to have a stroke compared with patients with RDW <13·27%, [OR 4·50; 95% CI: 2·50–8·01, P< 0·0001]	[30]
Wan et al, 2015	Prospective study	300 patients with AF	RDW was independently associated with all-cause mortality (HR: 1.024; 95% CI: 1.012–1.036, P <0.001) and major adverse events (HR: 1.012; 95% CI: 1.002–1.023, P=0.023).	[31]
Ertas et al, 2012	Retrospective	132 patients with no histories of AF undergoing coronary artery bypass grafting	Preoperative RDW levels were significantly higher in patients who developed AF than in those who did not (13.9 ± 1.4 vs 13.3 ± 1.2, p=0.03). Using a cut point of 13.45, the preoperative level correlated with the incidence of AF with a sensitivity of 61% and specificity of 60%.	[32]
Eryd et al, 2014	Prospective study	27,124 subjects from the general population without history of CVDs	HR for incidence of AF was 1.33 [95% CI 1.16–1.53] for the fourth versus first quartile of RDW P <0.001).	[33]
Osadnik et al, 2013	Retrospective	2550 consecutive patients with stable coronary artery disease	4-fold increase (4.3% vs 17.1%, p < 0.0001) in mortality between the group of patients with RDW values <13.1% vs >14.1%). RDW is an independent predictor of mortality in patients with stable coronary artery disease	[34]
Ye et al, 2011	Prospective study	13,039 consecutive outpatients with PAD	Subjects in the highest quartile of RDW (>14.5%) had a 66% greater risk of mortality compared to those in the lowest quartile (RDW <12.8%; P<0.0001). A 1% increment RDW was associated with a 10% greater risk of all-cause mortality (HR: 1.10; 95% CI, 1.08–1.12)	[36]