Evidence of Underdiagnosis of Sleep Apnea and Associated Abnormal Blood Pressure Control Among Minority Populations

Introduction: Obstructive sleep apnea (OSA) remains to be grossly underdiagnosed in the general population. We have recently shown that chemoreflex control of sympathetic nerve activity as measured by the pressor response to voluntary breathholding is exaggerated in patients with obstructive sleep apnea (OSA) and is highly sensitive for diagnosing OSA ([greater than] 0.90). In this study, we used the DSAP during volunteer breathholds to determine the pressor responses in a preliminary group of subjects from family medicine clinics who are not diagnosed with OSA. The population included African-Americans (AA), Hispanics (H) or Caucasians (C), and each subject also completed the EPWORTH sleepiness score (ESS) which is a marker of potential risk of OSA. Methods: Standard auscultatory blood pressure was measured in triplicate during quiet rest and immediately following a 20 sec voluntary end-expiratory breath hold (apnea) in 28 AA subjects, 16 H subjects and 48 C subjects who presented to the family medicine clinic without a diagnosis of sleep apnea. In addition, each subject completed the ESS survey and a score was calculated. Results: The entire cohort of subjects had reported to the clinic without a diagnosis of OSA. However, the ESS was significantly greater in both the AA and H groups when compared to the C subjects (p10 (high risk of OSA) was also significantly greater in the AA and H groups compared with the C cohort (p p Conclusions: These data derived from a general group of patients reporting to the primary care clinic support the premise that both AA and H individuals tend to be underdiagnosed for OSA and that the measurement of both the ESS and the pressor response to voluntary apnea can provide insights into both the risk of OSA and potential risk of underlying cardiovascular disease.