From the Guidelines
Hypertension (HTN) does not directly cause obstructive sleep apnea (OSA), but rather the relationship works primarily in the opposite direction, with OSA being a known risk factor for developing hypertension, as supported by the most recent guidelines 1. The intermittent hypoxia and frequent arousals from sleep in OSA activate sympathetic nervous system activity, increase oxidative stress, and cause inflammation, all of which contribute to elevated blood pressure. While HTN doesn't cause OSA, there is a bidirectional relationship where poorly controlled hypertension may worsen existing sleep apnea symptoms through fluid retention and redistribution to the neck area when lying down (rostral fluid shift), as noted in studies on resistant hypertension 1. This can increase upper airway collapsibility during sleep. Common risk factors for both conditions include:
- Obesity
- Advancing age
- Metabolic disorders If you have hypertension, especially resistant hypertension that doesn't respond well to multiple medications, it's advisable to be screened for OSA, as treating underlying sleep apnea often helps improve blood pressure control, according to recent guidelines 1 and studies on the treatment of sleep apnea 1.
From the Research
Relationship Between HTN and Obstructive Sleep Apnea
- Obstructive Sleep Apnea (OSA) is recognized as a cause of secondary hypertension, with a high rate of co-occurrence between the two conditions 2, 3, 4.
- The mechanisms underlying OSA-related hypertension include sympathetic activity due to intermittent hypoxia and/or fragmented sleep, leading to elevated blood pressure 2, 3.
- OSA can cause resistant hypertension, nocturnal hypertension, abnormal blood pressure variability, and vascular remodeling, making it essential to screen for OSA in patients with hypertension 2, 3, 5.
Impact of HTN on Obstructive Sleep Apnea
- There is limited evidence to suggest that hypertension (HTN) can directly cause obstructive sleep apnea (OSA) 2, 3, 4, 6, 5.
- However, the relationship between HTN and OSA is complex, and OSA is considered a major modifiable risk factor for hypertension 4, 5.
- The treatment of OSA with continuous positive airway pressure (CPAP) therapy can help lower blood pressure, but the magnitude of the decrease is relatively modest, and patients may still require antihypertensive medications 2, 3, 6.
Treatment and Management
- Antihypertensive medications targeting sympathetic pathways or the renin-angiotensin-aldosterone system may be effective in managing OSA-related hypertension, but current evidence is limited 2, 6.
- Beta-blockers and renin-angiotensin system inhibitors may be effective in the management of OSA-related hypertension, but more research is needed to confirm this 2, 6.
- Screening for OSA is essential in patients with hypertension, especially those with resistant hypertension, to improve blood pressure control and reduce cardiovascular risk 3, 5.