Population characteristics at noninvasive ventilation (NIV) initiation depending on adherence assessment at day 30

Patient characteristics at initiationTotalAdherence >4hAdherence <4hp-value
Anthropometric data
 Patients233153 (66)80 (34)
 Age (years)68±1168.1±10.668±11.20.907
 Male148 (63)101 (66)47 (59)0.274
 BMI (kg·m−2)24±524.4±4.6423±4.130.028
 Smoking greater than 20 pack-years21 (9)12 (7.8)9 (11)0.381
Initiation modality
 At home181 (78)126 (82)55 (69)0.018
 In hospital52 (22)27 (18)25 (31)0.018
 Time from NIV requirement assessment to initiation (days)12.3±16.612.6±19.111.5±10.20.647
 Died before the 30th day12 (5)0 (0)12 (15)
Neurological assessment
 ALSFRS-R score32.9±7.2834.3±6.3630.5±8.210.003
 Time from symptoms onset to NIV initiation (months)28.2±24.128.9±24.726.6±22.90.519
 Time from diagnosis to NIV initiation (months)14.9±18.615.3±18.214±19.50.623
 Bulbar symptoms at NIV initiation122 (52.6)75 (49)47 (59)0.173
 Gastrostomy in the follow-up13 (5.6)8 (5)5 (6)0.747
 Frontotemporal dementia18 (7.7)11 (7)7 (9)0.672
Respiratory assessment
 FVC (L)2.33±0.8712.4±0.8422.17±0.9210.108
 FVC (%)68.7±20.971.5±21.562.9±18.20.007
 Peak flow (L·s−1)4.58±1.994.8±2.044.08±1.810.036
 Peak flow (%)63.2±24.765.6±25.357.6±22.50.053
 MIP (cmH2O)44.7±23.746.6±22.840.2±25.60.178
 SNIP (cmH20)45.4±22.456±24.434.8±15.70.104
SpO2 night-time <90% (%)17.1±21.317.8±20.615.8±22.60.531
SpO2<90% more than 5% of night-time135 (68.2)95 (62)40 (50)0.024
SpO2 minimum80.4±7.8880.8±8.3379.6±7.010.317
SpO2 mean91.9±10.391.8±2.4392.1±2.370.468
PaCO2 (kPa)5.36±15.39±1.045.29±0.90.489

Data are presented as mean±sd or n (%) unless otherwise stated. ALSFRS-R: Amyotrophic Lateral Sclerosis Functional Rating Scale–Revised; BMI: body mass index; FVC: forced vital capacity; MIP: maximal inspiratory pressure; ODI: oxygen desaturation index; PaCO2: arterial carbon dioxide tension; SNIP: sniff nasal inspiratory pressure; SpO2: oxygen saturation measured by pulse oximetry.