Last week, a 65-year-old gentleman with diabetes was referred due to fluctuations in blood glucose values. His glucose values ranged from 40 to 400 mg/dL on the same day. He had had diabetes for 25 years and was being treated with insulin. Despite frequent dose adjustments, his sugar levels continued to drop, and his HbA1c (a measure of blood sugar control for three months) was high (9 percent versus the usual goal of 7 percent). He also complained of upper abdominal discomfort and occasional nausea and vomiting after meals.
It is not unusual for people with diabetes to complain of nausea and vomiting. One of the causes of nausea and heartburn in diabetes is the commonly used drug metformin. Another is simple GERD (gastro-intestinal reflux disease) which is very common in Indians. All of these factors were excluded in this patient. However the problem persisted.
After a detailed clinical and diagnostic evaluation, the patient was found to have a condition called diabetic gastroparesis, which literally means “partial paralysis” of the stomach and can be seen in long-term diabetes. In this case, the food stays in the stomach longer than it should because the stomach cannot push food into the intestines as it normally does. The condition is more common than we think and is often missed because it is not suspected.
Gastroparesis is caused by damage to the vagus nerve that supplies the stomach muscles due to diabetes. Typical symptoms of gastroparesis include “gastritis”, acidity and bloating after eating. Vomiting of undigested food several hours after a meal is sometimes an important diagnostic clue for the presence of gastroparesis. Some patients experience chronic abdominal pain, while others experience progressive weakness and weight loss. Because of the different transit times through the stomach, there is irregular absorption of nutrients from the stomach and duodenum, and wide fluctuations in blood glucose levels can be observed, as was the case in our patient. Chronic malnutrition may result from frequent vomiting and irregular food absorption.
Dehydration may be caused by severe, uncontrolled vomiting. The quality of life of patients with gastroparesis can be seriously affected.
Several tests are done to confirm the diagnosis of gastroparesis. The most important of these is the study of gastric emptying using a radioactive isotope labeled meal. It is a completely safe, non-invasive test but takes four hours. A breath test is sometimes used for diagnosis. The test can show how quickly your stomach empties after eating by measuring the amount of a certain substance in your breath. Upper GI endoscopy and abdominal ultrasound are also used, in particular to rule out other potential diagnoses such as gallstones.
Recently, electronic capsules have been developed that you can swallow and that can then send signals to an external receiver that can track the speed of movement.
What should you do if you have been diagnosed with gastroparesis? The first thing to do is adjust your diet. Eating small meals at frequent intervals is the key to success. No intermittent fasting or prolonged periods for you. The best way is to eat six to seven small meals a day. This way you will not stretch your abdominal muscles and you will not feel excessive bloating.
Contrary to the advice that is routinely given to diabetic patients, the food should be changed to low in fiber and low in leftovers. It is best to avoid raw fruits and vegetables that are rich in fiber. Instead, cooked vegetables and soups are recommended. Proper chewing, light food and more fluids (including plenty of water) are recommended. Sometimes this can be quite a challenge because a low-fiber food is quickly absorbed and can itself cause a spike in glucose levels. Your doctor will advise you how to deal with this. In addition, high-fat foods, carbonated drinks (“soft or cold drinks”), alcohol, and smoking can increase your symptoms, so it’s best to avoid them. One simple tip that helps many of my patients is to take a short walk after meals and avoid lying down for at least two hours after a meal.
Several medications are used in diabetic gastroparesis. Medicines that improve bowel movement called motility stimulants (eg metoclopramide) are commonly used. The antibiotic erythromycin is also useful in some cases, as it may speed up emptying of the stomach. Symptomatic treatments such as anti-nausea and vomiting medications should be used as recommended.
Surgical intervention can be used in the most advanced cases. The use of gastric stimulators is an interesting method. Gastric bypass surgery is a severe procedure in cases of obesity. Newer endoscopic procedures such as pyloromyotomy may also help some patients. Tube feeding or parenteral nutrition are temporary measures for severe cases.
How can we prevent the development of gastroparesis? Good diabetes control, right from the initial diagnosis of diabetes, is critical. A proper diet accompanied by the appropriate medication as described above will take care of most gastroparesis symptoms. One rarely has to resort to invasive methods.
(Author is Padma Bhushan Award Winner)