Red blood cell distribution width in elderly hospitalized patients with cardiovascular disease

Table 1 Baseline characteristics of the study population

Demographic/clinical
Age (mean ± SD, yr)	77.50 ± 7.41
Female sex, n (%)	94 (46)
Body weight (mean ± SD, kg)	76.28 ± 14.22
Height (mean ± SD, m)	1.66 ± 0.09
Systolic blood pressure (mmHg)	135(34.8)
Diastolic blood pressure (mmHg)	79 (21)
Heart rate (beats/minute)	73.5 (19)
Left ventricular ejection fraction (%) (median, IQR)	53.00 (37.50, 55.00)
Laboratory
RDW1 (mean ± SD)	15.48% ± 2.15%
C-reactive protein2 (mg/L) (median, IQR)	0.48 (0.16, 1.37)
Hemoglobin3 (mean ± SD, g/dL)	12.25 ± 1.92
Hematocrit3 (mean ± SD)	37.89% ± 6.04%
White blood cells3 (K/μL)	8.31 (2.85)
Urea (mg/dL) (median, IQR)	51.70 (38.60, 70.50)
Creatinine3 (mean ± SD, mg/dL)	1.21 (0.49)
SGOT4 (IU/L) (median, IQR)	20.15 (16.55, 25.65)
SGPT4 (IU/L) (median, IQR)	16.75 (11.65, 22.90)
K+4 (mean ± SD, mmol/L)	4.20 ± 0.56
Na+1 (mmol/L) (median, IQR)	140.00 (137.50, 142.00)
Non-cardiac conditions/morbidities, n (%)
Diabetes mellitus	68 (33)
Chronic obstructive pulmonary disease	37 (18)
Chronic kidney disease	84 (41)
Sleep apnea	15 (7)
Anemia	85 (42)
Cardiac conditions/morbidities, n (%)
Acutely decompensated chronic heart failure	104 (51)
Coronary artery disease	133 (65)
Hypertension	152 (75)
Atrial fibrillation	97 (47.5)
Medications (discharge), n (%)
Renin-angiotensin-aldosterone system inhibitors	159 (78)
Beta-blockers	145 (71)
Diuretics	137 (67)

¹Three values missing.

²Fifty-four values missing.

³Two values missing.

⁴Four values missing. RDW: Red blood cell distribution width; SGOT: Serum glutamic oxaloacetic transaminase; SGPT: Serum glutamic pyruvic transaminase.

Table 2 Results obtained from univariate linear regression analysis

Factor	Coefficient	95%CI	P value
Age	0.072	(0.033, 0.111)	< 0.001
Sex (males vs females)	-0.520	(-1.115, 0.075)	0.09
Weight	-0.014	(-0.035, 0.007)	0.18
White blood cell count	0.081	(-0.024, 0.185)	0.13
Urea	0.022	(0.014, 0.030)	< 0.001
C-reactive protein1	0.085	(0.001, 0.169)	0.05
Left ventricular ejection fraction	-0.057	(-0.073, -0.038)	< 0.001
Acutely decompensated chronic heart failure	2.220	(1.708, 2.732)	< 0.001
Coronary artery disease	0.039	(-0.573, 0.650)	0.9
Hypertension	-0.519	(-1.203, 0.165)	0.14
Atrial fibrillation	1.862	(1.322, 2.402)	< 0.001
Diabetes mellitus	0.854	(0.230, 1.477)	0.01
Chronic obstructive pulmonary disease	1.569	(0.810, 2.327)	< 0.001
Anemia	1.682	(1.123, 2.242)	< 0.001
Chronic kidney disease	1.590	(1.022, 2.158)	< 0.001
Sleep apnea	1.448	(0.289, 2.606)	0.02

¹Fifty-four values missing.

Table 3 Results obtained from the model selection procedure

Explanatory factors of RDW	Change in deviance1	P value
Models including 1 factor2
Age	12.84	< 0.001
Urea	26.50	< 0.001
C-reactive protein	4.01	0.05
LVEF	30.42	< 0.001
ADCHF	62.86	< 0.001
Atrial fibrillation	42.01	< 0.001
Diabetes mellitus	7.23	0.007
COPD	16.14	< 0.001
Anemia	32.69	< 0.001
CKD	28.60	< 0.001
Sleep apnea	6.04	0.01
Models including 2 factors3
ADCHF + Age	0.15	0.70
ADCHF + Urea	3.03	0.08
ADCHF + C-reactive protein	0.30	0.59
ADCHF + LVEF	0.06	0.80
ADCHF + Atrial fibrillation	19.33	< 0.001
ADCHF + Diabetes mellitus	3.08	0.08
ADCHF + COPD	2.39	0.12
ADCHF + Anemia	7.74	0.005
ADCHF + CKD	0.85	0.36
ADCHF + Sleep apnea	0.34	0.56
Models including 3 factors3
ADCHF + Atrial fibrillation + Age	0.08	0.78
ADCHF + Atrial fibrillation + Urea	2.10	0.15
ADCHF + Atrial fibrillation + C-reactive protein	0.54	0.46
ADCHF + Atrial fibrillation + LVEF	0.75	0.39
ADCHF + Atrial fibrillation + Diabetes mellitus	2.30	0.13
ADCHF + Atrial fibrillation + COPD	0.89	0.35
ADCHF + Atrial fibrillation + Anemia	8.35	0.004
ADCHF + Atrial fibrillation + CKD	0.73	0.39
Models including 4 factors3
ADCHF + Atrial fibrillation + Anemia + Age	0.50	0.48
ADCHF + Atrial fibrillation + Anemia + Urea	1.16	0.28
ADCHF + Atrial fibrillation + Anemia + C-reactive protein	0.34	0.56
ADCHF + Atrial fibrillation + Anemia + LVEF	1.86	0.17
ADCHF + Atrial fibrillation + Anemia + Diabetes mellitus	0.92	0.34
ADCHF + Atrial fibrillation + Anemia + COPD	0.77	0.38
ADCHF + Atrial fibrillation + Anemia + CKD	0.26	0.61

¹Largest change in deviance indicates the best model in each set (highlighted).

²Models were compared to the null model.

³Models were compared to those indicated as best in the previous set. ADCHF: Acutely decompensated chronic heart failure; CKD: Chronic kidney disease; COPD: Chronic obstructive pulmonary disease; LVEF: Left ventricular ejection fraction.

Table 4 Results obtained from multivariate linear regression analysis

Factor	Coefficient	95%CI	P value
Acutely decompensated chronic heart failure	1.406	(0.830, 1.981)	< 0.001
Atrial fibrillation	1.192	(0.673, 1.711)	< 0.001
Anemia	0.806	(0.256, 1.355)	0.004