0743 Should We Use AHI or RDI to Diagnose Obstructive Sleep Apnea?

Abstract

Abstract Introduction Sleep disordered breathing (SDB) is defined based on clinical complaints and polysomnography events. Obstructive sleep apnea (OSA) was initially diagnosed based on the apnea hypopnea index (AHI), but the ICSD-3 has defined the respiratory disturbance index (RDI) as the actual diagnostic criteria. This study aimed to evaluate and compare clinical outcomes related to daytime function in OSA patients defined by AHI and RDI. Methods This study was derived from the São Paulo Epidemiological Sleep Study (EPISONO), in its 3rd edition (2007) and follow up edition (2015). A total of 557 individuals had polysomnographies evaluated according to the 2012 American Academy of Sleep Medicine Scoring Manual in both editions. The scores of the Epworth Sleepiness Scale (ESS), Chalder Fatigue Scale (CFS), Pittsburgh Sleep Quality Index (PSQI), Beck Anxiety and Depression Inventories (BAI and BDI) and Insomnia Severity Index (ISI) were compared between individuals who sustained the same AHI level in both editions (either AHI<15 or AHI≥15). We did the same comparison between individuals who had either RDI<15 or RDI≥15. Results The grouping by AHI included 348 participants with AHI<15 and 107 with AHI≥15; while the grouping by RDI was composed by 335 with RDI<15 and 118 with RDI≥15. Considering the AHI grouping, there was no statistically significant differences in ESS, PSQI, BDI and ISI scores after 8 years of follow up (p=0.2, p=0.3, p=0.09 and p=0.7 respectively), but a significant increase in the CFS and BAI scores (p=0.05 and p=0.01, respectively) was observed. Considering the RDI grouping, there was no statistically significant difference on ESS, PSQI and ISI scores after 8 years of follow up (p=0.3, p=0.1 and p=0.4 respectively), but there was a significant increased on CFS, BAI and BDI. Conclusion OSA diagnosed by either AHI or RDI is associated with increase in fatigue levels. However, when OSA is diagnosed according to RDI, a worse depression score is observed. Depression complaints can significantly impair quality of life and should be consider an important SDB outcome. Support (If Any) AFIP, CNPq, CAPES.