TABLE 1

Demographic characteristics of the study population

Characteristics
Patients (male %)	642 (54.4%)
Age (years)	53.4 (42.9–63.1)
BMI (kg·m⁻²)	34.4 (28.9–40.0)
AHI (events·h⁻¹)	16.9 (7.7–36.0)
OSA
None (AHI<5)	107 (16.7%)
Mild (5≤AHI<15)	185 (28.8%)
Moderate (15≤AHI<30)	163 (25.4%)
Severe (AHI≥30)	187 (29.1%)
ODI_3% (events·h⁻¹)	13.6 (4.6–33.1)
Total sleep time (min)	330.3 (287.5–370.0)
All 5-min segments	39 132
Events per 5-min segment
Ev₀	20 873 (53.3%)
Ev_Q1	4663 (11.9%)
Ev_Q2	4997 (12.8%)
Ev_Q3	3752 (9.6%)
Ev_Q4	4847 (12.4%)
Desaturation severity
DesSev₀	23 191 (59.3%)
DesSev_Q1	3985 (10.2%)
DesSev_Q2	3986 (10.2%)
DesSev_Q3	3985 (10.2%)
DesSev_Q4	3985 (10.2%)
Comorbidities
Atrial arrhythmia	56 (8.7%)
COPD	58 (9.0%)
Diabetes mellitus, type 1	3 (0.5%)
Diabetes mellitus, type 2	115 (17.9%)
Hypothyroidism	65 (10.1%)
Hypertension	239 (37.2%)

Data are presented as median (interquartile range) for continuous variables and as n (%) for discrete variables. BMI: body mass index; AHI: apnoea-hypopnoea index; OSA: obstructive sleep apnoea; ODI_3%: oxygen desaturation index based on American Academy of Sleep Medicine 2012 scoring criteria (desaturation ≥3%); Ev₀: reference group with 0 respiratory events starting during the 5-min segment; Ev_Q1–4: severity groups pooled based on the number of respiratory events (apnoeas/hypopnoeas) starting during the 5-min segment (Ev_Q1=1<Ev_Q2≤3<Ev_Q3≤5<Ev_Q4); DesSev₀: reference group with desaturation severity of 0 during the 5-min segment; DesSev_Q1–4: severity groups pooled based on the desaturation severity in the 5-min segment (0%<DesSev_Q1≤0.305%<DesSev_Q2≤0.906%<DesSev_Q3≤2.463%<DesSev_Q4); COPD: chronic obstructive pulmonary disease.