Air pollution and heart failure: Relationship with the ejection fraction

Table 1 Clinical variables of 353 consecutive patients with heart failure: Comparison between patients with heart failure and preserved ejection fraction and patients with heart failure and reduced ejection fraction n (%)

Variables	HF-PEF(n = 124)	HF-REF(n = 229)	P value
Age (yr)	69 ± 8	66 ± 12	0.01
Male gender	56 (45.2)	154 (67.2)	< 0.001
Hypertension	75 (60.5)	84 (36.7)	< 0.001
Hypercholesterolemia	35 (28.2)	52 (22.7)	0.25
Smokers	14 (11.3)	40 (17.5)	0.12
Diabetes	45 (36.3)	104 (45.4)	0.09
LVEF (%)	55 ± 9	33 ± 6	< 0.001

Data are expressed as mean ± SD, and n (%) for categorical variables. HF-PEF: Heart failure with preserved ejection fraction; HF-REF: Heart failure with reduced ejection fraction; LVEF: Left ventricular ejection fraction.

Table 2 Data on atmospheric pollution in ambient air and meteorological variables between the previous day and the 7 d prior to admission for both of the study group

	HF-PEF(n = 124)	HF-REF(n = 229)	P value
Meteorological variables
Wind speedy (m/s)	2.72 ± 0.68	2.62 ± 0.78	0.21
Temperature (°C)	19.76 ± 2.52	20.08 ± 2.82	0.32
Relative humidity (%)	67.68 ± 6.10	66.85 ± 7.02	0.29
Gaseous pollutants (mg/m3)
CO	172.44 ± 23.89	177 ± 27.10	0.11
SO2	8.1 ± 4.40	7.33 ± 3.46	0.06
NO2	12.95 ± 8.22	4.50 ± 2.34	< 0.0001
O3	59.80 ± 12.52	61.25 ± 11	0.26
Atmospheric particles (mg/m3)
PM10	21 (13-30)	25 (17.5-32)	0.02
PM2.5	13.5 (9-21)	16.5 (11-21)	0.12
PM1	8 (6-16)	9.5 (7-13)	0.42

All of the pollutants are expressed as the average concentration of the pollutant. Data are expressed as mean ± SD, and median values (interquartile intervals). HF-PEF: Heart failure with preserved ejection fraction; PM: Particulare material with an aerodynamic diameter; PM10: PM < 10 μm; PM2.5: PM < 2.5 μm; PM1: PM < 1 μm.

Table 3 Multivariate binary logistic regression analysis including nitrogen dioxide as the main independent variable

	OR	95%CI	P value
Model 1 (unadjusted)
NO2	1.428	1.001-2.055	0.04
Model 2
NO2	1.669	1.043-2.671	0.03
Age	1.278	0.912-1.618	0.33
Model 3
NO2	1.429	0.992-2.058	0.05
Gender	0.948	0.111-8.067	0.96
Model 4
NO2	1.403	1.003-2.007	0.04
Hypertension	0.36	0.037-3.482	0.37
Model 5
NO2	1.516	1.005-2.397	0.01
LVEF	1.024	0.791-1.324	0.85
Model 6
NO2	1.489	1.009-2.453	0.01
PM10	1.124	0.997-1.974	0.94

LVEF: Left ventricular ejection fraction; NO₂: Nitrogen dioxide; PM: Particulare material with an aerodynamic diameter; PM10: PM < 10 μm.