fluid retention

Dr. Bradley was puzzled.  These patients with heart and kidney failure often had something else in common.  Sleep apnea.  Why?

In the most recent edition of HeadWay, we were exploring the connection between sleep apnea (or sleep apnoea) and migraine, headaches and cluster headache.  There’s good evidence for a strong relationship.  It seems many people with headache and migraine also have sleep apnea, and we know that sleep patterns are closely related to an increase in these other attacks.

Sleep apnea interrupts sleep, and can make you drowsy during the day.  It can also lead to serious heart problems and diabetes.

But the underlying cause of sleep apnea is not easy to explain.  We know that, for example, obesity is a risk factor.  But many people with sleep apnea are not obese, and are otherwise fairly healthy.  So what’s the problem?

Dr. Douglas Bradley, who we mentioned earlier, noticed that his patients did have something else in common.  Fluid retention (oedema).

Could fluid retention be causing the sleep apnea?

Dr. Bradley and his team set out to study 23 non-obese men.  When these men got horizontal to sleep, the fluid shifted in their bodies, and the circumference of their necks actually increased.  For the control group, it was an increase of 1/2 a centimetre.  But for those with sleep apnea, it was double that, 1 centimetre.  Why?  You guessed it.  Fluid.

So what’s happening?  Dr Bradley explains:

Gravity forces fluid down to the bottom of the body when you are sitting and your legs are inactive.  Standing and walking cause the calf muscles to contract, pumping fluid from the legs up through the veins toward the heart.

When you lie down to sleep, that "extra" fluid gets redistributed, causing the increase in neck circumference, which may be causing blockage leading to some sleep apnea.  (Read the story at Groundbreaking study results could help reduce the incidence of obstructive sleep apnea)

This surprising turn of events leads to some interesting treatments for sleep apnea, and so for the headaches it causes.

The first, best, and most obvious?  Move around!

If you tend to sit or even stand a lot of the day, try changing position, going for walks, getting your leg muscles working.  This keeps the fluid moving through your body the way it’s supposed to.

Dr. Bradley also suggests that elevating your upper body while you sleep may help, interestingly enough something that was recently discussed in a blog carnival entry Sleeping off my headache….

Other common treatments for fluid retention?  Don’t eat too much salt.  Drink plenty of water.  And how about this – one treatment for decreasing fluid retention that comes with the menstrual cycle is magnesium.  We keep coming back to that, don’t we?

One more interesting note.  Some drugs can increase fluid retention, such as NSAIDs (ie naproxen, oxaprozin and ibuprofen), and calcium channel and beta blockers, all commonly used for migraine, and often various types of headache.

Often sleep apnea is treated with special masks worn at night, implants, and even surgery.  But for many, this discovery may lead to solutions that are much less drastic.  And that means a lot less headaches.