Thursday, October 25, 2018

Glucose in Tears

About 20 years ago, shortly after I was diagnosed with type 2 diabetes, I read an article that described measuring blood glucose (BG) levels in tears. I thought that was wonderful, as it would avoid what popular press articles like to call "painful finger pricks" but which are actually not-very-painful but annoying tests one has to do multiple times a day if one wants good control.

So I mentioned the article to an endocrinologist who was in charge of a clinical study I was in. She laughed and said so many novel ways of measuring BG had been proposed, but none of them had ever made it to the market. "I'll be interested when it becomes commercially available," she said.

Well now, 20 years later, a company based in The Netherlands has proposed measuring BG levels in tears. This version involves putting a tiny sensor under the lower eyelid. The sensor measures BG levels continuously and broadcasts them to a smartphone.

The company has published the results of studies in six patients and says the device is accurate, with no adverse events reported. They are planning a study in 24 people with type 1 diabetes.

Well, it does sound nice, but I'll be interested when it becomes commercially available.

Friday, October 19, 2018

Beta Cell Rest

For many years, some people have been saying that if you can rest your beta cells by decreasing their workload, they can recover some function.

Richard Bernstein, the author of Dr Bernstein's Diabetes Solution, who promotes low-carbohydrate diets for people with diabetes, is one of them. He cites experiments with the Biostator, developed in the 1970s, a machine that kept blood glucose (BG) levels close to normal levels. After only 2 weeks on the machine, he said some people had normal BG levels for up to 2 years, despite eating a standard American diet. [I can't locate a reference for this study.]

The Biostator is large and bulky, and the patients had to be admitted to a research lab for the study, so it's not yet a practical solution, although so-called closed-loop insulin pumps are being developed. But it illustrates the concept. Keeping BG levels normal is good for your beta cells.

A similar effect is often seen in type 1 patients who have a "honeymoon period" shortly after they are started on insulin. However, that effect doesn't last.

There hasn't been much experimental evidence on this topic, although there is some, see here and here. So it was nice to see a recent study that supports the concept. Although, like so many studies, it was done in mice, the results are interesting.

The authors say that improving glucose levels with various diabetes drugs not only increased the insulin content of the beta cells, but restored normal biphasic insulin secretion.

Normally, beta cell secretion of insulin occurs in two phases. After eating carbohydrate, the first phase is very rapid, and it doesn't last long. But it keeps BG from going very high, in part by stopping the liver from releasing glucose. The second phase occurs later and persists until no more carbohydrate is coming into the intestine, and it is able to keep the BG down for a long time.

People with type 2 diabetes almost always lose the first-phase insulin response. This means the BG goes very high after a carbohydrate load, and because it's so high, if they're still able to secrete insulin, the beta cells secrete a lot of it. This is often so much that the person later goes low. In fact, going low about 4 hours after a carbohydrate-rich meal is one of the warning signs of future diabetes. I had this about 5 or 10 years before I was diagnosed with type 2.

So the fact that the first-phase insulin response was restored is promising. I also learned that my first-phase insulin response was restored to about 70% of normal when I was in a study of high-dose aspirin at Joslin. I assume I lost it again when the study was over, although I had no way of testing that.

These authors conclude, "Thus, this study provides evidence that alleviation of metabolic demand on the beta cell, rather than targeting the beta cell itself, could be effective to delay the progression of T2D."

And how can people alleviate the metabolic demand on the beta cell? By eating less carbohydrate, of course. In fact, the "normal" BG levels reported for the Biostator  are not as good as those reported by type 1 patients on the Type1Grit Facebook page. (If you're not on Facebook, you can see results here.) The Biostator was set for BG levels of 90, but they actually fluctuated a lot.

 Low-carb diets have been anathema among some diabetes organizations like the American Diabetes Association, but they are slowly gaining acceptance even by these groups.

Another way to reduce the load on the beta cell is to inject insulin. The standard treatment of type 2 used to be to tell people to lose weight and exercise and come back in three months. Now some say it's better to start right out on insulin. This will reduce the workload on your beta cells and let them recover somewhat at a time when you still probably have a lot of them. Here is an example of that. Then when they have recovered a bit, you can phase out the insulin.

Waiting for three months, especially if given a high-carb low-fat diet, will just burn out more of these precious cells. And most overweight patients have been trying unsuccessively to lose weight for decades, so telling them to lose weight isn't very helpful.

One problem is that some people don't like needles, and they see using insulin as a sign of failure. It's not. It's taking charge of your health. And if you use it from the get-go so your beta cells recover and you then stick to a sensible diet, you may be able to go off all drugs in the future.

Rest your beta cells, and your beta cells will thank  you.