Hypoglycemic Unawareness
Sometimes people who have had diabetes for many years develop hypoglycemic unawareness — blood glucose lows that they don't know about because they don't show any symptoms. This may be caused in part by damage to the sympathetic nervous system (called autonomic neuropathy), in which the typical involuntary reactions to low blood sugars — such as sweating and flushing — don't occur. For some people with this condition, a loss of consciousness is their first and only sign that their blood glucose has dipped dangerously low.
Are there any devices that can wake me up from a low at night?
Today's continuous blood glucose monitoring systems have alarms that can be set to go off if your blood sugar drops too low or climbs too high. Another device called the Sleep Sentry sounds an alarm when it detects perspiration or a drop in skin temperature — two signs of a hypo.
If you experience lows frequently, you're more likely to develop hypoglycemic unawareness. This can be an unintended side effect of a regimen of intensive blood glucose control. These patients are three times more likely to experience hypoglycemic unawareness than those on a nonintensive treatment program. And if you have a hypo, your risk of having yet another low is higher for up to two days following the episode.
If you're trying to keep your blood sugars in tight control, you have a fine line to walk, and sometimes you end up in a vicious cycle of low after low. Eventually, hypoglycemic unawareness may result. This is another reason testing your blood sugar levels frequently is so important.
Fact
Several studies have found that moderate intake of caffeine may be useful in heightening sensitivity to symptoms of blood glucose lows in those patients with hypoglycemic unawareness. Be sure to check with your doctor first, as too much caffeine can have negative consequences, particularly if you have high blood pressure.
If you develop hypoglycemic unawareness while on an intensive control program, your doctor will probably recommend increasing your target blood glucose levels slightly to avoid dangerous lows. Some clinical studies have shown that loosening control to allow blood glucose levels to run slightly high for two to three weeks can restore hypoglycemia awareness in some patients.
Blood glucose awareness training may also be an option for you if you have hypoglycemic unawareness. Frequent monitoring, increased awareness of hypo triggers, and recognition of some of the subtler signs of a low are the focus of this type of training.
Anyone who experiences blood glucose readings of 50 mg/dl or less without any signs of hypoglycemia should let their doctor know immediately. It is probably a sign of hypoglycemic unawareness, and some adjustments to treatment may be in order.
