Among the numerous tasks performed by the human brainstem, one of the most vital is that of regulating the body’s cardiovascular system, which relies on neurons based in the brainstem to maintain a low resting heart rate. According to a new study published in the Journal of Physiology, individuals suffering from obstructive sleep apnea (OSA) frequently experience a diminishing of this neural activity. In turn, the study concludes, these individuals are at a higher risk of developing health complications such as elevated heart rate and high blood pressure, as well as of experiencing adverse cardiovascular events.
OSA is characterized by repeated interruptions of breathing during sleep, creating a series of oxygen deficits that propel the patient into lighter sleep states or moments of wakefulness in order that normal breathing may be restored. In severe cases of sleep apnea, pauses in breathing and arousal from sleep can occur as often as once per minute, leaving the patient mentally and physically exhausted. A significant portion of the population suffers from this cardiovascular disease, with 9% of adult females and a remarkable 24% of adult males experiencing sleep apnea. This being the case, the present study represents a vital step in the medical community’s endeavors both to explore the long-term effects of OSA on the human body and to promote cardiovascular health.
Employing rats as their test subjects, researchers developed their conclusions by replicating OSA conditions for a four-week period. During this time, they monitored the synaptic activity of the parasympathetic neurons that control heart rate, as well as recording changes in the rats’ blood pressure and heart rate. In summarizing the researchers’ findings, study leader Dr. David Mendelowitz of the George Washington University USA explains that the inhibition of brainstem neurons responsible for maintaining a low resting heart rate can lead to a sustained dulling of cardiovascular reflexes. This means that in the long-term, untreated OSA may increase one’s risk of developing irregular heartbeat and high blood pressure. Moreover, the study also has implications for individuals who regularly use sleep medicines, suggesting that these, too, may elevate one’s risk of experiencing an exaggerated reduction of the neural activity that controls heart rate.
While the present study sheds light on some of the serious health complications to which OSA sufferers may be subject, this research also gives new hope to doctors and patients seeking to mitigate the long-term effects of sleep apnea, and perhaps especially the established correlation between sleep disorders and stroke. Utilizing these findings as a foundation, future research in this area will likely focus on exploring possible approaches to the restoration of functionality among the neurons responsible for maintaining heart rate with the aim of reducing the risks of hypertension, elevated heart rate, arrhythmias, and other conditions that accompany OSA.
At Rowe Neurology Institute, we have the most current diagnostic tools for the diagnosis of sleep disorders, and a staff of neurologists and integrated caregivers who specialize in sleep disorders. We perform 1,500 in lab sleep studies annually in our nationally accredited sleep disorders center. We believe it’s extremely important for patients to see their sleep studies in detail. So they can be their best selves and have a full understanding of their sleep disorders. We show them how.