Effect of Hypertension on Left Ventricular Diastolic Dysfunction Associated with Obstructive Sleep Apnea.

PURPOSE: Obstructive sleep apnea (OSA) and hypertension are known cardiovascular risk factors, but the effect of hypertension on OSA-related left ventricular diastolic dysfunction remains unclear.

PATIENTS AND

METHODS

This cross-sectional study enrolled 289 patients from the Second Affiliated Hospital of Fujian Medical University (January 2013-January 2023). Participants were classified as healthy controls (HC), OSA-only (OSA), hypertension only (HTN), and OSA with hypertension (OSA-HTN). Furthermore, based on the AHI (Apnea-Hypopnea Index) values, the OSA group and the OSA-HTN group were further divided into three subgroups: mild (5≤AHI<15 events/hour), moderate (15≤AHI<30 events/hour), and (AHI≥30 events/hour). Participants underwent biochemical testing, echocardiography, and polysomnography. Echocardiographic parameters of diastolic function-interventricular septum thickness (IVST), left ventricular posterior wall thickness (LVPW), left atrial volume index (LAVI), E/A ratio, and E/e' ratio-were compared among the groups. One-way analysis of variance and statistical interaction analysis evaluated the independent and interactive effects of hypertension and OSA severity on E/e'.

RESULTS

Compared with the HC group, the HTN, OSA, and OSA-HTN groups showed significantly higher IVST, LVPW, LAVI, and E/e' ratio (p<0.05), with the OSA-HTN group exhibiting the greatest impairment. The E/e' ratio increased with OSA severity and correlated positively with systolic blood pressure and diastolic blood pressure, most strongly in the OSA-HTN group. Hypertension (mean difference=-1.784, 95% CI: -2.868 to -0.701, p=0.001) and OSA severity independently affected E/e' with a significant multiplicative interaction (p<0.05).

CONCLUSION

Both hypertension and severe obstructive sleep apnea are independently associated with impaired left ventricular diastolic function, and their coexistence may have a potential synergistic effect.