Table 1.
Clinical characteristics of studied population.
| Variable | All n = 184 (100) | no PNX n = 169 (92) | PNX n = 15 [8] | HR (CI 95%) | P |
|---|---|---|---|---|---|
| Age, years (IQR) | 79 (69–86) | 79 (69–86) | 81 (74–84) | 1.007 (0.960–1.050) | >0.05 |
| Male sex, n (%) | 98 (53.3) | 92 (54.4) | 6 (40.0) | 0.619 (0.220–1.743) | >0.05 |
| Smoking abitude, n (%) | 96 (52.2) | 85 (50.2) | 11 (73.3) | 2.606 (0.829–8.194) | >0.05 |
| Obesity, n (%) | 79 (42.9) | 72 (42.6) | 7 (46.6) | 1.170 (0.420–3.260) | >0.05 |
| Comorbidities, n(%) | |||||
| Diabetes | 31 (16.8) | 29 (17.1) | 2 (13.3) | 0.672 (0.149–3.024) | >0.05 |
| Arterial hypertension | 97 (52.7) | 89 (52.6) | 8 (53.3) | 0.903 (0.324–2.513) | >0.05 |
| Heart disease | 44 (23.9) | 41 (24.2) | 3 (20.0) | 0.834 (0.233–2.990) | >0.05 |
| Kidney disease | 14 (7.6) | 12 (7.1) | 2 (13.3) | 1.476 (0.330–6.603) | >0.05 |
| Dementia | 54 (29.3) | 40 (23.6) | 14 (93.3) | 31.181 (4.089–237.793) | 0.0009 |
| Blood gas parameters and ventilatory support | |||||
| PaO2/FIO2(>200), n (%) | 124 (67.4) | 118 (69.8) | 6 (40.0) | 0.338 (0.119–0.959) | 0.041 |
| PaO2/FIO2 mmHg (IQR) | 262 (185–304) | 266 (192–304) | 106 (56–309) | 0.990 (0.986–0.997) | 0.004 |
| NIV, n (%) | 84 (45.4) | 71 (42.0) | 13 (86.6) | 7.970 (1.760–36.088) | 0.007 |
| Outcome | |||||
| Mortality at day 30, n (%) | 69 (37.5) | 56 (33.1) | 13 (86.6) | 5.097 (2.518 10.317) | <.0001 |
| Hospital stay days, n (IQR) | 13 [[8], [9], [10], [11], [12], [13], [14], [15], [16], [17], [18], [19], [20]] | 14 [[8], [9], [10], [11], [12], [13], [14], [15], [16], [17], [18], [19], [20]] | 9 [[2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15]] | >0.05 | |
| Hospital stay days, min-max | (0–73) | (1–73) | (0–41) | >0.05 | |
| Day of PNX diagnosis, n | 9 | 9 | |||
Data are presented as number and percentage for dichotomous values or median and interquartile range (IQR) for continuous values.
Abbreviations: HR, Hazard Ratio; CI, confidence interval; PNX, Spontaneous pneumothorax; NIV, non-invasive ventilation; PaO2, arterial oxygen partial pressure; FiO2, fraction of inspired oxygen.