Results
Patients with OSA-I and OSA-II represented 6% (n=84, 71% males) and
10% (n=144, 72% males) of the national cohort (n=1449) respectively.
OSA-II patients were older at CPAP/NIV initiation (mean age 11.0 ± 4.0
vs 6.8 ± 4.5 years, p<0.001) (Table 1). OSA-II patients were
treated with CPAP/NIV for a longer time than OSA-I patients (mean
duration 2.3 ± 2.6 vs 1.3 ±1.5 years, p=0.008). A minority of patients
were treated with NIV as compared to CPAP, with no difference between
patients with OSA-I and OSA-II (6% of OSA-I vs 13% of OSA-II patients,
p=0.142). For both groups, the overall duration of ventilatory support
was greater for patients treated with NIV as compared to patients
treated with CPAP (4.0 ± 3.0 vs 1.7 ± 2.1 years, p<0.001)
(Table 1). The objective adherence was similar for both groups (mean
adherence 6.8 ± 2.6 hours/night and 5.9 ± 3.0 hours/night for OSA-I and
OSA-II patients, respectively, p=0.054). However, in both groups, the
objective adherence was greater with NIV as compared to CPAP (Table 1).
The 5 OSA-I patients treated with NIV were younger at NIV initiation as
compared to those treated with CPAP, they were treated with NIV for a
longer time, and were also more adherent to treatment as compared to
patients treated with CPAP. The 19 OSA-II patients treated with NIV were
also treated for a longer time than those treated with CPAP.
Nearly all the patients had a polysomnography (PSG) or a respiratory
polygraphy (PG) prior to CPAP/NIV initiation (Table 2), with
approximately half of the patients having a simultaneous recording of
transcutaneous carbon dioxide pressure (PtcCO2), with no
difference between patients with OSA-I and OSA-II. Only a minority of
patients (4%) had only a nocturnal recording of pulse oximetry
(SpO2) and PtcCO2 without a PSG or a PG.
CPAP/NIV was initiated on a high AHI in 68% of the patients, and on a
high AHI with an abnormal SpO2 and
PtcCO2 value in 24% of the patients, with no difference
between patients with OSA-I and OSA-II (Table 2). CPAP/NIV was initiated
on an abnormal SpO2 and PtcCO2 alone in
only 4% of the patients. On note, the 5 patients with OSA-I who were
treated with NIV had all a PtcCO2 recording, whereas the
44 patients who did not have a PtcCO2 recording were all
treated with CPAP. Of the 19 patients with OSA-II who were treated with
NIV, only 2 had no PtcCO2 recording.
Patients with OSA-II were treated more often with a standard device, and
less often with an intermediate and life support device, as compared to
patients with OSA-I (Table 3). Patients treated with a standard device
were older than those treated with an intermediate or life support
device, with a greater age difference for patients with OSA-I as
compared to patients with OSA-II (Table 4). The mean age of the patients
treated with an auto-titrated CPAP was 11.4 ± 3.6 and 14.4 ± 3.3 years
for patients with OSA-I and OSA-II, respectively. Both groups used most
often a nasal interface with around 20% of patients in both groups
using a nasobuccal interface. Patients with OSA-II were treated with a
higher CPAP level in case of CPAP, while the inspiratory and expiratory
pressures were not different between sub-groups in case of NIV even
though they tended to be higher in patients with OSA-II (Table 5).