White coat hypertension and obstructive sleep apnea

Area of Science:

• Cardiology
• Sleep Medicine
• Hypertension Research

Background:

• White coat hypertension (WCH) is characterized by elevated blood pressure in clinical settings but normal readings outside.
• Obstructive sleep apnea (OSA) is a common sleep disorder associated with cardiovascular complications.
• The interplay between WCH and OSA and their long-term impact on blood pressure progression is not fully understood.

Purpose of the Study:

• To investigate the blood pressure characteristics and long-term progression in patients with co-existing white coat hypertension (WCH) and obstructive sleep apnea (OSA).
• To compare these characteristics with patients having WCH alone and healthy controls.

Main Methods:

• A longitudinal study analyzing 26-month data on systolic blood pressure (SBP), diastolic blood pressure (DBP), and sleep test results.
• Inclusion of three groups: WCH with OSA (n=28), WCH only (n=23), and healthy controls (n=27).
• Utilized 24-h ambulatory blood pressure monitoring to assess diurnal BP patterns and non-dipper status.

Main Results:

• WCH patients with OSA exhibited significantly higher daytime and nighttime BP and a reduced diurnal BP variation compared to WCH and control groups.
• The prevalence of 'non-dipper' status was significantly elevated in WCH patients with OSA.
• Sustained hypertension developed in 42.8% of WCH patients with OSA, a rate significantly higher than in the other groups, and was predicted by non-dipper status.

Conclusions:

• White coat hypertension may serve as a prehypertensive state.
• The presence of obstructive sleep apnea can accelerate the progression of WCH to sustained hypertension.
• Non-dipper status identified via ambulatory blood pressure monitoring is a significant predictor of sustained hypertension in WCH patients with OSA.