A man who simply won’t lose weight

Seasonal delicacies may harbor hidden diet pitfalls.

Issue: December 2008

ByRonald Tamler, MD, PhD, MBA

Last fall, I saw a 25-year-old man with type 2 diabetes for an initial visit. He had been diagnosed with diabetes two years prior and had not tolerated regular metformin or its extended-release version. After a brief period of glimepiride, and then sitagliptin (Januvia, Merck), he was now taking exenatide (Byetta, Amylin) 10 mcg twice daily monotherapy, but was forgetting four injections per week. The patient confessed to eating pizza, ice cream and fast food, which was contributing to his obesity and poor glycemic control. He did not bring his glucometer to the visit. HbA1c was above goal at 7.9%.

Ronald Tamler

There was no other relevant medical history. The patient had no drug sensitivities, did not take any other medications or supplements, was a non-smoker and had one alcoholic beverage per week. He denied use of recreational drugs. He lived with his daughter and his supportive (albeit exasperated) wife, who accompanied him during his visits.

Physical exam was remarkable for an obese 25-year-old white male: heart rate 68, BP 130 mm Hg/80 mm Hg, 5’6” tall, 270 lb and a BMI of 43. The patient had dry skin with acanthosis and large neck circumference. He denied snoring, and his wife denied witnessing episodes of sleep apnea.

Other than the HbA1c, alanine transaminase was increased to 169, aspartate transminase at 63, with normal alkaline phosphatase and bilirubin. Chemistry, lipids and urine microalbumin were otherwise at goal or normal.

The patient vowed to adhere to his medical regimen and, given his poor compliance with diet, agreed to keep a food log. He saw our diabetes educator/nurse practitioner, who found out that the patient was skipping breakfast to then feast on hot dogs and bagels with cream cheese. The patient took her dietary advice to heart, and by the time he saw me for his next visit in early January, he was eating breakfast and logging more sensible food choices. He was consistently taking his exenatide, and his blood glucose levels were generally in the low 100s. HbA1c was 6.9%, and liver function tests were normalized. His weight, however, had increased to 276 lb and was a source of great frustration.

The patient was still keeping a food log and proudly presented a log that was consistent with an intake of approximately 1,800 kcal per day. His wife confirmed that he appeared to have improved his dietary habits, but she too was complaining about the weight gain.

What is the most plausible explanation for this patient’s weight gain, despite improving blood glucose levels and documentation of a more sensible diet?

The patient was not taking his exenatide properly.

His wife was surreptitiously mixing pioglitazone into his supper.

The patient was wearing more clothes and had more change in his pocket.

Improved glycemic control always leads to weight gain.

The patient was consuming calories from a source that he is not logging in his diary.

CASE DISCUSSION

We commonly see this patient in our practice: Obese, poorly compliant with diet and medications, desperate to lose weight. Unfortunately, this patient did not tolerate metformin due to gastrointestinal adverse events — it would have worked very well with the exenatide.

The improved glycemic control, as evidenced by blood glucose levels and HbA1c, indicated that the patient was taking his medication properly and regularly (A). However, it is never wrong to make sure that drugs are taken as prescribed, with the proper technique. While exenatide can lead to weight loss, it is not a certain outcome. That said, it is one example of how glycemic control and weight gain certainly do not go hand in hand. On the contrary: weight loss, be it with diet, with medical or with surgical treatment, will improve glycemic control (D). One scenario when weight gain is indeed compatible with improved glycemia is the addition of thiazolidinediones to the regimen. However, unless the wife has access to pioglitazone, this is a rather unlikely scenario.

One of my favorite excuses for higher weight is when patients claim they are wearing heavier clothes or have more coins in their pockets. This argument can be easily avoided by having patients wear gowns during their appointments. If not, an allowance of 1 lb can be made for the occasional sweater. However, it is impossible to explain a 6-lb weight gain with pocket change (C).

The remaining explanation (E) demands some patience and detective skills. Many people will not perceive “diet” products or beverages as relevant sources of calories. While our patient had heeded my advice and stayed away from beer and regular sodas, he had taken up a new habit: Every November morning, he would pick up a 20 oz Starbucks Pumpkin Spice coffee with whipped cream. On workdays, he would return for a second serving in the afternoon. In December, he switched to the Eggnog latte.

I led him to the excellent Starbucks website and demonstrated the caloric effect of every single drink: 530 kcal for the Pumpkin Spice and 630 kcal for the Eggnog latte — more than 1,000 kcal per day, accounting for an approximate difference in weight of 2 lb per month. It was an eye-opening experience for the patient, who has since switched to espressos and lost weight.

Ronald Tamler, MD, PhD, MBA, is an Assistant Professor in the Division of Endocrinology at Mount Sinai School of Medicine, N.Y.