Diabetes and Hypothyroidism: Partners in Ill Health

Patient Expert

What's wrong with you if you have diabetes along with mood fluctuations, if you are anxious, if you often get angry, and if you have a poor memory? Are you just a bad person?

Did you even consider that you might have an underactive thyroid gland? Lots of people have this condition, which doctors call hypothyroidism. And even a greater proportion of people with diabetes have it. I'm one of them.

Few doctors ever check us to see if our thyroid gland is working properly. Even fewer treat it because of  inconsistent standards  regarding what a healthy thyroid is.

Dr. Kesavadev (right) and Me (Photo by Gopika Krishnan)

But one doctor who runs a large diabetes clinic has been concerned for years about hypothyroidism among his patients. I met him three years ago in San Diego at the Scientific Sessions of the American Diabetes Association.   He is Jothydev Kesavadev, M.D., of  Jothydev's Diabetes and Research Center  in Trivandrum, India, which is also known as Thiruvananthapuram and is the capital of the state of Kerala located on the west coast of India near the extreme south of the country.

At the ADA convention three years ago, Dr. Kesavadev  presented preliminary research  that found that almost half of the 1,000 people with diabetes they screened had either hypothyroidism or hyperthyroidism. Yet only 1.8 percent of them knew ahead of time that they had either too high or too low a thyroid level. And only about 4 percent of people who  don't  have diabetes have hypothyroidism.

Dr. Kesavadev told me that what is unique to people with diabetes is that doctors generally miss testing us for hypothyroidism "in 99.99 percent of the cases." Weight gain, tiredness, loss of memory, and lethargy are common to both diabetes and hypothyroidism, and clinicians never think of checking it, he says.

Last month, a research team headed by Dr. Kesavadev presented a much larger study to the  annual meeting of the European Association for the Study of Diabetes  in Vienna, Austria. During the past five years, they screened 7,402 consecutive patients with type 2 diabetes for hypothyroidism.

While approximately 6 percent of their patients reported that they had hypothyroidism, 30 percent had abnormal levels. Of these, 10 percent had subclinical levels (3.04-10 µIU/mL), 17 percent had overt hypothyroidism (>10 µIU/mL), and 2 percent had such low levels (<0.05 µIU/mL) that they probably had  _hyper_thyroidism. The abstract of the researcher's study, "Prevalence of undetected thyroid disorders in subjects with diabetes in South India: a cohort analysis," is  free online.

"Diabetes patients will tremendously benefit from early detection of thyroid disorders," the study concluded. This is especially important because hypothyroidism among people with diabetes is "significantly higher than in the general population," and "many a time symptoms of hypothyroidism in diabetes patients are mistaken for hypoglycemia"and hence goes grossly undetected."

The standard treatment for hypothyroidism is a tiny pill taken the first thing every morning to make up for the thyroid hormone we lack. The generic name of the pill is levothyroxine (or the brand name Synthroid). It was developed way back in the 1950s, and has been thoroughly tested and found to be very effective.

But by coincidence, a task force on thyroid hormone replacement of the American Thyroid Association just studied alternatives to levothyroxine. They reported their finding in a 207-page article in the peer-reviewed journal  Thyroid.  It's free online at "Guidelines for the Treatment of Hypothyroidism" in case you don't have anything else to do this week.

I tried but didn't get far beyond the conclusion that "levothyroxine should remain the standard of care for treating hypothyroidism." Generic levothyroxine is working for me.

In 1996, a lab tested my level for the first time and reported that it was 4.23 µIU/mL. Both the lab and my endocrinologist told me that it was "OK." It wasn't.

Four years ago, when my primary care physician told me that I had a subclinical level of 4.17 µIU/mL, I had increased sensitivity to cold. My feet felt cold most of the time. This physician finally prescribed levothyroxine. My most recent lab test found that my level is low enough and my feet are much happier.

You may also be much happier when you manage your unruly thyroid gland.