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. 2018 Nov 1;13:3625–3634. doi: 10.2147/COPD.S169951

Table S2.

Prognostic value of baseline variables and NIV settings on survival according to univariate Cox regression analysis

na HR 95% CI P-value
Age (years) 233 1.032 1.008 to 1.056 0.008
BMI (kg/m2) 222 0.938 0.905 to 0.973 0.001
Pack years 169 1.000 0.992 to 1.008 0.981
Gender (female) 233 0.733 0.504 to 1.068 0.106
Living alone 212 0.891 0.548 to 1.448 0.641
NIV started after ARF 233 2.106 1.420 to 3.124 <0.001
PaO2 (kPa) 222 0.920 0.794 to 1.067 0.270
PaCO2 (kPa) 228 1.331 1.151 to 1.538 <0.001
ΔPaCO2 (%)b 104 0.988 0.965 to 1.012 0.320
ΔPaCO2 (kPa)c 104 1.157 0.910 to 1.472 0.234
HCO3− (mmol/L) 221 1.115 1.067 to 1.165 <0.001
FEV1 (% predicted) 217 0.968 0.947 to 0.990 0.005
FEV1/FVC (%) 215 0.993 0.970 to 1.016 0.526
RV/TLC (%) 110 1.036 0.988 to 1.076 0.066
Diuretics 233 1.011 0.695 to 1.471 0.955
SRI, total score 129 0.983 0.966 to 1.000 0.054
Comorbid disease
 Obstructive sleep apnea 192 0.423 0.185 to 0.968 0.042
 Anxiety 209 1.347 0.900 to 2.016 0.148
 Depression 207 0.849 0.567 to 1.273 0.428
 Diabetes mellitus 225 1.369 0.859 to 2.182 0.186
 Hypertension 221 0.864 0.574 to 1.301 0.484
 Coronary artery disease 222 1.086 0.632 to 1.866 0.765
 Congestive heart failure 223 1.206 0.714 to 2.037 0.483
NIV settingsd
 IPAP (cmH2O) 201 1.005 0.951 to 1.062 0.866
 EPAP (cmH2O) 201 0.935 0.812 to 1.076 0.347
 BURR (breaths per minute) 201 1.018 0.949 to 1.092 0.623
Compliance (hours)d 146 0.934 0.812 to 1.074 0.338

Notes:

a

Number of patients included in the analysis;

b

Percentage of change in PaCO2 between baseline and 12 months;

c

Absolute change in PaCO2 between baseline and 12 months;

d

NIV settings and compliance after 3 months. The values in bold are considered statistically significant (P<0.05).

Abbreviations: ARF, acute respiratory failure; BURR, backup respiratory rate; EPAP, expiratory positive airway pressure; HCO3−, arterial bicarbonate; IPAP, inspiratory positive airway pressure; NIV, noninvasive ventilation; PaCO2, arterial carbon dioxide pressure; PaO2, arterial oxygen pressure; RV, residual volume; SRI, severe respiratory insufficiency questionnaire; TLC, total lung capacity.