Squeaky clean

Method does matter

In user guides and how-to videos, blood glucose meter companies detail every step they want you to take when you check your blood glucose level. Yet study after study has shown that most people skip one or more of the steps.

Maybe you think the steps can’t all be important. Maybe you’ve heard different advice elsewhere. Or maybe you need some evidence of their value in achieving accurate results. Here, we’ll examine the most basic step – washing your hands, which may seem trivial or open to interpretation.

For those of you in a hurry, see the tips below for what’s best, according to research.

TO WASH OR NOT

Do you need to wash your hands before you check your blood glucose? Or is a quick wipe on your jeans good enough?

In a recent study published in Diabetes Care, 123 people had their blood glucose levels checked by fingerstick and handheld meter 1) on unwashed hands 2) after washing their hands with soap and water, drying them and then handling fruit and 3) after handling fruit and then washing and drying their hands again.

The researchers, led by Johanna Hortensius at the Diabetes Center, Isala Clinics, in the Netherlands, considered a reading acceptably accurate if it differed by less than 10 per cent from the control (washed and dried hands).

• Unwashed hands (no fruit): When the first drop of blood was used, in about 1 in 9 tests the reading was more than

10 per cent higher than the readings from washed hands. Wiping away the first drop of blood with a tissue and using the second drop eliminated most of the false increases.

• Handling fruit: Each participant sliced or peeled a piece of fruit and tested without washing. The results from the first drops of blood were, on average, 110mg/dl higher than the readings from washed hands. Again, wiping away the first drop and testing the second helped bring the result closer to the control, but not enough. The researchers concluded that the first drop of blood should be used for self-monitored glucose testing only after washing hands. If washing hands is not possible and they are not soiled or exposed to a sugarcontaining product, use the second drop of blood.

SOAP WINS

Are hand sanitiser and alcohol wipes as good as soap and water?

Cindy Young, a nurse and diabetes educator in Maine, has been getting reports from clients that when they use certain hand sanitisers, they get higher readings. Young, who does not have diabetes, ran her own tests. After she washed with soap and water, her blood glucose reading was 99. After she used plain gel hand sanitiser, it was 98; after hand sanitiser with lotion, it was 115. If you use hand sanitiser, you may want to run some comparisons to see if it’s affecting your readings.

If you’re concerned about germs, soap and water still wins. According to the Centers for Disease Control and Prevention, “Washing hands with soap and water is the best way to reduce the number of germs on them. Alcohol-based hand sanitisers can quickly reduce the number of germs on hands in some situations, but sanitisers do not eliminate all types of germs.”

How about alcohol wipes? In an earlier study by Hortensius’s group and reported in The Netherlands Journal of Medicine, the fingers of 25 people were soiled with glucose, fruit, jam, honey and chocolate. The researchers wiped the soiled fingers with chlorhexidinealcohol solution, an antiseptic used to clean skin before surgery. The readings from the first drops of blood were, on average, 14mg/dl higher than the readings taken from soiled fingers that had been washed with soap and water.

There’s another problem with alcohol wipes. Christopher Stein at the University of Johannesburg, South Africa, found not allowing the alcohol to evaporate before sticking the finger led to an average increase in the reading of about 9mg/dl. That’s fairly insignificant, Stein says, but if you’re concerned, “wipe the first drop of blood off the fingertip and use the second drop, which effectively removes the small error”.

Plain soap and water are best. Hand sanitiser and alcohol wipes may leave residue on your fingers.