To achieve good blood sugar control, you must periodically check your blood glucose levels to see how you are doing. Usually every type 2 diabetic is encouraged to take blood glucose readings at home at intervals ranging from once a week to several times a day, especially when changing diet or medication. The doctor who treats your diabetes should recommend a blood glucose testing schedule for you and ask to see your results every time you visit him.
Tens of millions of diabetics spend tens of billions of dollars every year for expensive test strips and glucometers.
But is home testing or self testing of blood glucose levels really reliable? A 2008 test by the US Centers for Disease Control (CDC) suggests that glucometers are good for telling you whether your blood sugar levels are going up or down, but not very reliable for determining absolute blood sugar values.
Scientists at the CDC tested five commonly used glucometers: MediSense Precision Xtra, Ascencia Dex, Prestige Smart System, OneTouch Ultra, and Accu-Chek Advantage. The scientists found that if you were to do a blood test and then try another test a few seconds later, the blood sugar levels would not vary a whole lot. In their studies, readings varied 3 to 11% with the same blood sample.
Different glucometers, however, give very different readings of the same blood sample, with values differing by as much as 32%. Moreover, the higher your blood sugars, the more likely the glucometer is to disagree with lab values. Glucometers are really reliable only for measuring blood sugars below 100 mg/dL (5.5 mmol/L).
Home glucose testing is not perfect, but is the best system diabetics have for keeping track of blood sugar levels. Diabetics should be sure to wash their hands before taking a reading. It's also helpful to take a blood sugar reading at home before having your blood tested at your doctor's office, so you can compare glucometer readings with the values that come back from the lab. The real blood glucose level is almost always higher than the blood glucose level you get at home.
Meters that can give you an accurate reading on your blood glucose without you having to prick your finger are in the development stage... they are not yet available. No-stick glucose meters will probably be expensive when they first appear on the market, but as with the current testing meters, the prices will drop.
Blood glucose meters usually work well for a long time, however, because they're mechanical devices, few work perfectly.
