Gut dysbiosis tied to sleep apnea hypertension

Last Updated: 2016-01-13

By David Douglas

NEW YORK (Reuters Health) - Studies in rats indicate that a high-fat diet coupled with gut dysbiosis can lead to obstructive sleep apnea-induced hypertension, according to Texas-based researchers.

In a December 28 online paper in Hypertension, Dr. David J. Durgan of Baylor College of Medicine in Houston and colleagues note that OSA is a significant risk factor for cardiovascular disease. In fact, as many 80% of patients with drug-resistant hypertension may have OSA.

They further point out that commensal bacteria, particularly the gut microbiota, play a critical role in modulating host metabolism, immunity, and inflammation. Gut dysbiosis has been linked to a variety of pathologies including obesity, diabetes, and atherosclerosis, as well as hypertension.

To examine whether such dysbiosis contributes to OSA-related hypertension, the team modeled the condition in rats by repeatedly inflating and deflating a tracheal balloon during the sleep cycle. When the animals had a normal chow diet, OSA had no effect on blood pressure.

However, when animals were given a high-fat diet, blood pressure increased by 24 mm Hg after 7 days and 29 mm Hg after 14 days of OSA. Examination of fecal pellets isolated before and after 14 days of OSA in chow and high-fat fed rats showed significant alterations of the gut microbiota.

Moreover, transplant of dysbiotic cecal contents from the hypertensive OSA rats to those on a normal chow diet resulted in hypertension similar to that of the donors. There was an increase of 14 mm Hg at 7 days and 32 mm Hg at 32 days.

Commenting on the findings by email, Dr. Durgan told Reuters Health. "Our studies demonstrate that gut dysbiosis plays a causal role in the development of obstructive sleep apnea-induced hypertension. This understanding will allow us to explore methods to manipulate the microbiota as a potential treatment for obstructive sleep apnea-induced, and possibly other forms of hypertension."

The National Institute of Neurological Disorders and Stroke and the Public Health Service supported this research. The authors reported no disclosures.

SOURCE: http://bit.ly/1ZDDJG3

Hypertension 2015.