Sleep Articles & Research Publications

This pilot study investigated a new simplified OSA screening tool that could be used in primary care/GP settings – the “GPSS” tool – “General Practice Sleep Scale” and compared against common existing OSA screening tools.

A convenience sample of patients attending the respiratory and sleep clinic in the Northern Territory of Australia were included if they completed the GPSS prior to undergoing a diagnostic polysomnography. The GPSS contained 9 questions to provide information on: sex, age, body mass index, neck circumference, snoring, witnessed apnoeas, morning tiredness, daytime sleepiness and presence of hypertension/diabetes/heart disease/depression. Presence of OSA was defined as an apnoea-hypopnoea index of ≥15/hour. The GPSS scoring was developed via log odds of regression predictions for each GPSS question upon OSA.

159 patients (65% male, median age 45 years) were enrolled. A minimum score of 1 was assigned to GPSS questions, up to 5 for the strongest predictor (neck circumference). The median total GPSS score was 13 (IQR 9, 16) (maximum 22) and correlated strongly with OSA (AUC 0.812 (95% CI 0.744, 0.881)). Categorised into low (0–7), moderate (8–13) or high risk (>13), a moderate or severe score had sensitivity 100%, specificity 34.9%. The GPSS significantly outperformed the Epworth Sleepiness Scale, Berlin questionnaire and OSA-50, and was comparable but slightly improved against the STOP-Bang.

Obstructive sleep apnea/hypopnea syndrome (OSAHS) is an important and common public health problem with increasing incidence. Polysomnography (PSG) is the gold standard test in OSAHS diagnosis. Apnea-hypopnea index (AHI) is the main parameter of PSG correlated with OSAHS severity.

The main complaint of OSAHS patients is daytime sleepiness and the Epworth Sleepiness Scale (ESS) is used for evaluation of disease severity. 648 patients presenting with snoring and apnea were evaluated by polysomnography and anthropometric measurements. Cut-off value of ESS was accepted as 10 as an indicator of severe daytime sleepiness. Patients were stratified into groups according to AHI values.

Patients with similar AHI values exhibited significantly divergent ESS scores. BMI and neck circumference were markedly elevated in daytime sleepiness patients. Nocturnal hypoxemia markers (apnea number/index, maximum duration of apnea, minimum SaO2 concentration, duration of SaO2 < 90%) were heavily affected in the group with daytime sleepiness.

To test the hypothesis that obstructive sleep apnea (OSA) can mask concurrent periodic limb movements during sleep (PLMS), which becomes evident or worsens after treatment with continuous positive airway pressure (CPAP).

A total of 142 consecutive patients (29 women, 113 men; mean age 53±10 years; BMI 31±6 kg/m²) referred to PSG for OSA diagnosis (PSG1) and CPAP titration (PSG2) on two different nights were retrospectively evaluated.

The frequency of patients with PLMS index > 5 events per hour of sleep was 13 (9%) in PSG1 and 18 (13%) in PSG2. Only four patients had PLMS index > 5 in both PSGs. A decrease of the PLMS index was observed in two of the four patients who sustained PLMS index > 5 in PSG2 compared to PSG1.