IJCS | Volume 31, Nº5, September / October 2018

501 Table 1 - Clinical characteristics of the groups of patients Parameter CG (n = 54) IG (n = 48) p values Age, years 67.2 ± 6.1 69.3 ± 5.6 p = 0.67 Gender (male: female) 32 : 22 26 : 22 χ 2 = 0.1, p = 0.75 BMI (kg/m 2 ) 26.6 ± 0.9 24.8 ± 0.5 p = 0.07 Smoker (actual) n = 31 (57%) n = 31 (64%) χ 2 = 0.04, p = 0.83 Duration of smoking, years 32.5 ± 5.8 27.7 ± 3.5 p = 0.5 FC II (NYHA) n = 9 (17%) n = 10 (22%) χ 2 = 0.04, p = 0.84 FC III (NYHA) n = 35 (65%) n = 30 (62%) χ 2 = 0.01, p = 0.96 FC IV (NYHA) n = 10 (18%) n = 8 (16%) χ 2 = 0.01, p = 0.96 FEV1/FVC 0.62 [0.55 - 0.66] 0.60 [0.57 - 0.62] p = 0.34 Diabetes mellitus, type 2 n = 12 (22%) n = 9 (19%) χ 2 = 0.01, p = 0.91 Arterial hypertension n = 45 (83%) n = 35 (73%) χ 2 = 1.07, p = 0.3 Hypercholesterolemia n = 28 (52%) n = 27 (56%) χ 2 = 0.06, p = 0.8 History of myocardial infarction n = 35 (65%) n = 35 (73%) χ 2 = 0.05, p = 0.82 CG: control group; IG: intervention group; BMI: body mass index; FC: functional class; NYHA: New York Heart Association; FEV1: forced expiratory volume for 1 second; FVC: forced vital capacity. Babkina et al. Influence of pulmonary rehabilitation Int J Cardiovasc Sci. 2018;31(5)499-504 Original Article with an oximeter (M70; Biolight, China) while the patients were breathing room air. Statistical analysis Processing of the results was performed on a personal computer using statistical analysis package “Statistica 6.0”. The D’Agostinho & Pearson, Shapiro- Wilk and Kolmogorov-Smirnov tests were used to test the normality of data distribution. The paired and unpaired Student t test was used for comparisons of continuous, normally distributed variables between groups. The Mann-Whitney test was used for analysis of continuous variables without normal distribution, and the chi-square statistics for categorical variables (clinical features). Results are shown as mean and standard error for continuous, normally distributed variables, and as median and interquartile range (25 th -75 th percentile) or percentage (as appropriate) for the others. Significant association was defined by p value < 0.05. Results The pre-specified duration of the enrollment period was two years and during that time we interviewed 168 patients. Forty-two did not meet inclusion criteria, 24 declined to participate. A total of 102 patients were enrolled, 54 to CG and 48 to IG. At baseline, there were no significant (p > 0.05) differences between the groups in the patients’ clinical characteristics (Table 1). At admission patients received in both groups standard therapy in comparable doses. By the end of the observation period, a significant reduction in office heart rate (HR), respiratory rate (RR) at rest, severity of dyspnea by the Borg scale, the number of points by CES, and increased 6MWT distance were observed in both groups. Moreover, all these changes were more considerable in the IG as compared with the CG (Table 2). Oxygen saturation increased in both groups (in CG: from 93 (84; 95)% to 94 (83; 97)%, p = 0.01; in IG: from 93 (84; 95)% to 98 (95; 98)%, p < 0.001), more pronounced in IG (p = 0.03). A reduction of CHF FC (NYHA) was observed in 82% of the IG patients and only in 61% of the CG patients ( χ 2 = 4.55, p = 0.03). Average duration of hospitalizationwas shorter in the IG (16.7 ± 3.1 days versus 19.9 ± 3.8 days in CG, p < 0.05).