Dear Dr. Roach • I was recently prescribed a CPAP machine for mild-moderate obstructive sleep apnea. I have a history of benign paroxysmal positional vertigo and wondered if the pressure of the CPAP might cause the vertigo to kick in. — L.B.
Answer • Benign paroxysmal positional vertigo is believed to be caused by calcium crystals in the organ of balance, the semicircular canals, in the inner ear. The usual presenting symptom is vertigo, commonly described as the room spinning, often associated with nausea. People who have had this type of vertigo once are at risk for getting it again.
Obstructive sleep apnea is caused by relaxation of the soft tissues of the upper palate and the back of the throat, preventing proper breathing. While it is commonly associated with being overweight, OSA can happen in people of any weight. Continuous positive airway pressure, the CPAP machine, helps to keep the airway open and allow for unobstructed breathing.
Some people using CPAP note nasal congestion or swallowing air at night. These symptoms can generally be managed by a provider familiar with this treatment. However, triggering BPPV is not an issue with CPAP. In fact, by improving the oxygen supply to the balance centers of the brain, treatment of OSA has been shown to improve balance problems in some people.
Don’t let fear of vertigo dissuade you from the best treatment for your sleep apnea.
Dear Dr. Roach • I often read that sodium is bad, particularly for blood pressure. But is it much of an issue if your blood pressure is normal? I enjoy salt on many foods and don’t really watch my intake because I’ve had very consistent healthy pressure readings my entire life. I’ve always been between 110 and 120 systolic and between 65 to 75 diastolic. I’m now over 60 and fairly active but not as much as I used to be. Should I worry about the amount of salt I eat? — B.C.
Answer • High sodium intake does have health consequences, even for people with normal blood pressure, but the overall risk is low.
First, it increases the risk of kidney stones. Increased sodium causes the kidney to excrete more calcium. Reducing sodium is a clear recommendation for people who already have stones.
Second, people who consume more salt are more likely to develop high blood pressure, and need medication for it. Avoiding salt means less risk of needing medication in the future.
Third, there is some evidence that even people with a normal blood pressure are at a higher risk for stroke if they consume excess salt. However, evidence is lacking to say that salt reduction alone leads to lower risk of stroke in people with normal blood pressures. Nonetheless, I believe a lower salt diet is likely to have health benefits, especially when looked at for an entire population — meaning that any given person may have a small benefit, but if enough people do, lives will be saved.
Many high salt foods are also highly processed and have other health harms besides salt and no benefits.
Readers may email questions to ToYourGoodHealth@med.cornell.edu or send mail to 628 Virginia Dr., Orlando, FL 32803.