Impact of different hypopnea definitions on obstructive sleep apnea severity and cardiovascular mortality risk in women and elderly individuals

Autores de IIS La Fe

• Miguel Ángel Martínez García

  Autor

• María José Selma Ferrer

  Autor

Participantes ajenos a IIS La Fe

• Campos-Rodriguez, F
• Reyes-Nunez, N
• Punjabi, NM
• Farre, R

Grupos

• Neumología

Abstract

Objective: To assess the impact of three hypopnea definitions on the severity classification of obstructive sleep apnea (OSA) and its association with cardiovascular mortality risk in women and elderly individuals. Methods: We analyzed two Spanish clinical cohorts (1116 women and 939 elderly individuals) who were studied for suspicion of OSA between 1998 and 2007. A calibration model was used to apply different definitions of hypopnea to our two cohorts. Hypopnea was defined as a 30-90% reduction in oronasal flow for >= 10 s followed by (1) >= 4% fall in oxyhemoglobin saturationd-AHI(4%); (2) >= 3% fall in oxyhemoglobin saturationd-AHI(3%); or (3) >= 3% fall in oxyhemoglobin saturation or an event-related arousald-AHI(3%a). Results: In both cohorts, the prevalence of an AHI >= 30 events/h increased by 14% with AHI(3%a), compared to AHI(4%) criteria. The percentage of women with an AHI <5 events/h decreased from 13.9% with AHI(4%) to 1.1% with the AHI(3%)a definition. In fully adjusted multivariable analyses, AHI >= 30 events/h was associated with increased cardiovascular mortality risk in women, regardless of the hypopnea definition, and in elderly individuals diagnosed using the AHI(4%) and AHI(3%) but not the AHI(3%a) definition. Conclusions: Our findings suggest that hypopnea definitions substantially influence OSA prevalence and severity classification, and also affect the association with cardiovascular outcomes. With the currently recommended criterion (AHI(3%a)), a threshold of 30 events/h is appropriate to identify women, but not elderly individuals with increased risk of cardiovascular death. (C) 2016 Elsevier B.V. All rights reserved.

Keywords

• Sleep apnea; Apnea-hypopnea index; Hypopnea definition; Cardiovascular mortality; Scoring