PERFORMANCE OF SIX SCREENING SCORES FOR OBSTRUCTIVE SLEEP APNOEA IN AN AFRICAN POPULATION.

Introduction: A screening tool for obstructive sleep apnoea (OSA) is useful in low-income countries where it may be difficult to access sleep recordings. The objective of this study was to assess the performance of six screening scores compared with objective sleep recording in an African population sample. Methods: This analysis is based on the "Benin Sleep and Society" (BeSAS) populational study in which respiratory polygraphy (PG) was performed using a type III device and OSA screening questionnaires (STOP, STOP-Bang, Berlin, NOSAS [≥ 8 and ≥ 5), No-Apnea, GOAL) were administered to participants. PG-defined OSA severity categories were defined according to the apnoea-hypopnoea index (AHI): mild (AHI 5 to <15/h), moderate (AHI 15 to <30/h) or severe (AHI≥30/h), and these were compared to score findings. Results: A total of 1810 subjects (mean age 45.4±14.6 years; 57.3% women) were included. For moderate to severe OSA, the area under the receiving operating characteristic (ROC) curve was greatest for GOAL and No-Apnea (0.70), followed by NoSAS5 (0.69). The highest sensitivity values were for NoSAS5 (0.73), No-Apnea (0.72), and GOAL (0.69), while NoSAS8 had the highest specificity (0.91), followed by Berlin (0.88) and GOAL (0.71). All scores performed poorly with respect to the positive predictive value (PPV), which was highest with NoSAS8 (0.38). Conclusion: This study provides the first comparison of the performance of screening scores for OSA in an African population. Although still low, PPV was highest with NoSAS8. Hence, NoSAS8 would be the screening method of choice for OSA in resource-constrained settings where formal sleep recordings are not accessible.

EVALUATION OF A MODIFIED EPWORTH SLEEPINESS SCALE TO RELIABLY ASSESS EXCESSIVE DAYTIME SLEEPINESS IN LOW-INCOME COUNTRIES: RESULTS FROM THE BENIN SOCIETY AND SLEEP (BESAS) STUDY.

Background: The Epworth Sleepiness Scale (ESS) is a tool widely used to assess excessive daytime sleepiness. Unfortunately, it is not reliable in low-income countries where situations such as reading a book, watching TV or driving a car are not common. The aim of this study was thus to assess the performance of a modified version of the Epworth scale in a low-income country. Methods: We used data from the Benin Society and Sleep (BeSAS) study where the ESS and a modified ESS (mESS) were administered to participants. In the mESS, questions four questions over eight were redesigned to reflect common living situations in Benin. The internal coherence of the mESS was assessed using the Cronbach alpha coefficient (CAC). The discriminatory ability of the scale was assessed by comparing the mean scores according to reported sleep quality, insomnia complaints and apnea-hypopnea index (AHI). Results: A total of 2909 participants were recruited, 1129 were male (38.9%) with a mean age (SD) of 44.7 (14.5) y. Overall, 52.4% (1526) completed all the mESS questions while 453 (15.6%) completed the standard ESS. The CAC of the mES was 0.86 showing good internal coherence. Concerning the discriminatory ability, mean scores for mESS were 7.8 for participants with ISI < 8 vs 9.2 for participants with ISI≥8 (p<0.001), 7.8 for participants withPSQI<5 vs 8.3 for participants with PSQI≥5 (p=0.03). No difference was found when comparing the participants participants using different cut-offs of AHI (15 and 30). Conclusion: The mES is more reliable than ES in the Beninese population. mESS shows good internal coherence and differentiates between insomniacs vs non-insomniacs and between good and poor sleepers. Although the mES is not a perfect score, it appears more relevant in the Benin population than the original Epworth scale but needs further validation/improvement in other low-income countries.