Fingers Still Crossed - Because We Still Want a Non-Invasive Meter
"It feels like you accidentally pricked yourself with a pin, only it's not accidental and you have to do it over and over again in the same areas."
That's how Maria Beyer describes blood glucose testing. As if insulin injections weren't enough of a pain, Beyer says the finger-stick glucose monitor that she's used since the mid-1990s causes sore, cracked and callused fingertips.
It seems the recent news of a breath test for checking blood glucose would offer her some comfort. According to a study out of the University of California, Irvine, breath analysis testing may prove to be the first effective, noninvasive way for diabetics to track blood sugar levels.
But when the study made headlines in late September, Beyer was neither comforted nor convinced. To someone who has lived with type 1 diabetes for decades, this kind of news is just the same old story.
"Every few years they say they've found the answer, but I'm still waiting," says Beyer, who was diagnosed in 1972, just a few weeks after her 18th birthday.
Despite all of the advancements toward a less painful technology, a completely noninvasive blood glucose meter - one that offers an accurate reading without piercing the flesh - has yet to hit the market.
Granted, some devices do allow patients to lance alternative sites like toes, forearms, thighs or ear lobes. But the pain still exists, and even more so in a highly sensitive spot like the toe. Moreover, alternative site testing isn't always reliable, as readings from these areas may not reflect rapid changes in blood glucose levels.
Hence, the finger-stick method continues to prevail.
A Catch 22
For the more than 200 million diabetics around the world, keeping blood sugar levels under control is vital to preventing kidney failure, heart disease, loss of vision and other complications. Current studies show that keeping these levels as close to normal as possible can reduce complications by up to 60 percent.
Most self-monitoring plans recommend testing before meals, two hours after meals, at bedtime, and anytime symptoms of high or low blood sugar occur. Yet, due to the trauma this daily regimen can bring, many people with diabetes resist testing their blood as often as doctors suggest.
"If poking your finger sounds like no big deal, try doing it four times a day for 10 or 20 years," says Beyer.
Signs of the daily struggle of people with diabetes are scattered throughout Beyer's home in rural Wisconsin: On the nightstand, antibiotic ointment for sore fingers and chocolate mints for midnight hypoglycemic attacks. On the bookshelf, an assortment of religious, inspirational and self-help books. In the pantry, stacks of note cards with low-fat and low-carb recipes. On the counter, post-it notes with reminders like "Must test blood at bedtime."
One morning in December, Beyer's blood glucose tests at 343 mg/dL - more than 200 points above the normal range. Even though she hasn't eaten anything since 7 p.m. the night before, she blames herself for this unusually high reading.
"I didn't feel like testing my blood last night, and this is what happens," she says. "It's hard to follow the rules all the time, especially when you're tired and just want to go to sleep."
The pain factor is just one of many reasons to avoid frequent testing. Beyer says the social stigma of needles and bloody test strips can be even harder to handle. For the past 20 years, she has worked part-time as a waitress at a chain pizzeria. At least once during her shift, she must test her blood in a public bathroom stall.
"It's the only place that gives me any privacy. I would test in the break room, but it makes my coworkers cringe."
Add up these issues, and it's easy to see why people with diabetes would prefer a method that doesn't involve blood.
Hope Against Hype
A former chief executive officer and chief scientific officer with Fovioptics and LifeScan research companies, respectively, Dr. John L. Smith evaluated more than 100 noninvasive meters before writing about the many complexities surrounding them.
In his book, 'The Pursuit of Noninvasive Glucose: Hunting the Deceitful Turkey' published online in 2006, Smith admits that developing a noninvasive meter is among the greatest technical challenges he has ever faced.
"It is not, perhaps, as difficult or fraught with problems as time travel or the absolute, final cure for cancer, but it is the more tantalizing because it has seemed for decades that the solution was always 'just around the corner.'"
Indeed, one needs only to search "noninvasive blood glucose" via Google to find more than a million results on the grab bag of miracle monitors that have come and gone in recent years.
Be it a futuristic laser beam or a color-shifting contact lens, both the scholarly journals and popular media outlets cover each new technology with the same tone: Diabetics, rejoice! Your finger-sticking days may finally be over.
The reality, however, is usually quite different from the advanced press. Take the GlucoWatch G2 Biographer, for example. In the early 21st century, the U.S. Food and Drug Administration approved this noninvasive device to continuously detect glucose trends in children, adolescents and adults with diabetes.
Manufactured by Cygnus Inc., the GlucoWatch measured blood sugar levels transdermally, using an electric current to extract glucose molecules from the skin. Worn like a wristwatch, the device could provide six measurements per hour for 13 hours.
But the GlucoWatch wasn't perfect. It was never intended as a stand-alone unit. Rather, it was to be used along with the conventional finger-stick method.
Evidently, many journalists overlooked this imperfection. In 2001, leads such as the following appeared in newspapers across America:
"People with diabetes are about to get a science fiction-like way to measure their blood sugar painlessly."
This overstatement made it all the way to Hollywood. 'Panic Room', David Fincher's 2002 thriller, centers on a woman and her diabetic daughter who lock themselves in a secret room while burglars invade their New York mansion. As the two ladies hide, the GlucoWatch alerts the daughter to a dangerous drop in her blood sugar.
In response to the film, several people posted questions online, eager to know more about the mysterious movie prop: "Is the wristwatch real? Does is work? If so, what's the make and model? How much does it cost?"
To their disappointment, the GlucoWatch has since been proven to cause skin reddening, burning and blisters, and has been deemed unreliable to boot.
"The product is no longer manufactured, the company went bankrupt, and its assets were eventually sold to…an insulin pump company that had abandoned its own glucose monitoring system a few years before," Smith explains in his book.
Considering the constant flood of announcements claiming the noninvasive problem has been solved, it's no wonder Beyer is cynical about the breath analysis test.
She's not the only one. In a recent report to one of the world's leading consultants for diabetes-related product investment, Smith points out that the breath test has actually been "discovered" several times in the past few years.
"So far, it has never panned out, but it makes a great story and grabs headlines," he says.
In the University of California study, the research team analyzed exhaled gas profiles of plasma glucose levels in 10 children with type 1 diabetes. While the findings suggest that breath analysis has potential, Smith believes this measurement is not likely to be placed into a home monitoring device in the near future.
"Because the gas is an indirect product of hyperglycemia, it is likely to have a significant delay, possibly even longer than the 30 minutes they reported," Smith writes in the report mentioned above. "The [results] need to be both fast and accurate, so this is not something I would invest in."
Smith says the premature announcements are often made to generate publicity and financial support for fledgling companies. Sadly, they also raise false hope in people who really need the technology.
This isn't to say that scientists aren't trying hard to develop a noninvasive technology that works. As of 2007, the home glucose testing industry represents a $6 billion-plus market worldwide. That figure would most likely increase if testing were less painful and no bloodletting was involved.
"A noninvasive monitor has been regarded as the 'holy grail' of medical device venture capital opportunities for many years," says Smith. For these reasons and more, "hope springs eternal in the hearts of scientists, entrepreneurs, opportunists and charlatans alike."
So, What's the Holdup?
Glucose is tricky, to say the least. First, with a normal glucose level, people have only about a teaspoon of dissolved sugar in their bloodstream. Second, it's colorless in most spectrums, making the molecule virtually impossible to see with both the naked eye and the most advanced, light-detecting technology.
Third, the chemical structure of glucose is very similar to many other compounds within the human body. Because the body consists of many glucose-like molecules, most noninvasive monitoring techniques produce overlapping results.
As Smith illustrates time and again in his book, the many difficulties of the measurement process - from calibration of the instruments to validation of the results - have, so far, kept scientists and research companies from finding a noninvasive solution that works.
Yet another cause for concern, he says, is that many technologies have been explored after others have already proven they won't succeed. "Because there has been no accounting of these multiply-investigated approaches, both investigators and investors have no guideposts to direct them."
Maybe something will come of the University of California study, and millions of people with diabetes will finally enjoy some relief. But for now, at least, Beyer's not holding her breath.Click Here To View Or Post Comments