In a recent video, Dr. Robert Lustig, of UCSF Medical School, called obesity “the gift that keeps on giving.” He was referring to the metabolic effects that “diabesity” in the mother have upon the fetus (aka; epigenetic affect, interuterine effect, metabolic memory of the child, etc.). We know that obesity in many people is likely a condition of insulin resistance and that this insulin resistance may cause a host of metabolic problems linked to obesity: hyperinsulemia and eventually type 2 diabetes, hypertension and stroke, dislipidemia (low HDL, high triglycerides, high small-dense LDL) and inflammation (hyperglycemia, AGE production, and C-reactive protein) leading to heart disease, cancer (many tumors associated with breast and colon, to name a few, feed off of elevated insulin, insulin-like growth factor, and glucose to increase replicative rate and risk of metastasis), Alzheimer’s (Type III diabetes or “brain diabetes”), gout (high uric acid buildup in blood stream), etc.
Now there’s another “gift” of obesity: sleep apnea. There now appears to be an epidemic of sleep apnea among the obese.
I shadowed a wonderful physician on Wednesday May 9th for 5 hours who has transitioned from pulmonology work to running a sleep clinic full-time due to the huge business now found in sleep apnea. He estimated that around 95% of his practice is devoted to sleep apnea while around 70% of these cases are either overweight or obese.
Why does excess body fat cause sleep apnea, i.e. make people awaken at night (“sleep” = at night; “apnea” = to awaken)?
It’s hypothesized that a person’s excess body fat forces their airway closed at night which can cause some individuals to awaken as much as 100 times an hour throughout the night (that’s 800 times during a normal 8 hour night of sleep). This constant awakening stresses their system (can exacerbate CVD, diabetes, acid reflux) and leaves many people exhausted the next day despite the impression, at least in the patient, that they got a full night’s sleep.
The physician explained it to a patient whose obstructive sleep apnea was causing them to awaken 60 times an hour, or, once-a-minute: “Imagine if I snuck into your room and strangled you once a minute. When you wake up, I’m gone. But I’ll be back 59 seconds later and do the same thing again, and again, and again…hundreds of times a night. Thousands of times a week.”
Scary stuff. But accurate.
Not only does sleep apnea place an individual at increased risk of motor vehicle accident, crashing a plane (some pilots suffer from the condition), falling asleep at the job, missing cherished play time with their kids, etc., it also may either generate or exacerbate the conditions of CVD, hypertension, acid reflux, and diabetes.
The stress response causes the body to release adrenaline, which causes the body to dump fatty acids and blood sugar into the system (exacerbating diabetes), raises blood pressure (which worsens hypertension and may eventually lead to stroke), exacerbates acid relux, ie. GERD, by causing the esophageal sphincter to relax and allow stomach acid to enter the esophagus, and all of these conditions likely stress the heart, setting up the individual for increased risk of a heart attack (many obese people also have CHD or CVD…).
A 2005 US Dept. of HHS, AHRQ systematic review estimated that between 2-4 percent of middle-aged adults have sleep apnea. Given the increased awareness and diagnosis of sleep apnea, and increasing prevalence of obesity in adults, it’s likely that the actual current prevalence may be higher.
CPAP machines (“continuous positive airway pressure”) are given to patients with sleep apnea to keep their airway open and prevent the occurence of sleep apnea. Modern CPAP machines monitor the time of use, number of SA events, etc. among patients and it does, at least in patients at this clinic, appear that CPAP works very well to prevent the occurrence of SA.
There are side-effects of CPAP, though they’re minor (drying of the throat being the main one). Still, if patients use the machine faithfully every night, SA diminishes to such an extent that many patients enter the “normal range” of waking 5 or less times and hour.
However, many patients fail to use the machine faithfully. Like so many aspects of preventative medicine, it is up the patient to use the drug or treatment continuously, day in and day out, for the patient to be spared either disease incidence or disease progression.
Patient adherence is another discussion but, CPAP adherence in SA sufferers appears to help these patients tremendously. Many see full cessation of SA symptoms and are able to get a full, healthy night of sleep for the first time in, for many sufferers, DECADES.
Treating SA means increased high-quality, REM sleep, which means a happier, healthier, and less accident-prone wakening life for these patients. Kudos to the doctors who treat this condition and kudos to the marvels of modern medical technology.
However, if the majority of obstructive sleep apnea (and even central sleep apnea- occurring mainly in CVD patients) is due to excess body fat, then most of the SA disease burden in the American adult population could be prevented by not allowing these individuals to become obese in the first place.
This means altering the food environment to make it less “obesegenic” – which is another conversation. Please see my “Diabesity” page for more information.