Tuesday, September 30, 2014
Weight Gain From Thyroid Problems
I have been diagnosed with a 2.7 cm complex cystic thyroid nodule in the right lobe. I was first diagnosed in 2004 and reevaluated in April of 2006. The nodule has grown. I have had two ultrasounds and a non-diagnostic biopsy where fluid was drained but not enough tissue was retrieved to make a diagnosis of benign or malignant. I just went to see an endocrinologist who ordered a calcitonin bloodwork test, a TSH and PTH intact and, of course, another biopsy. Over the last two years I have noticed a slow weight gain, and my cortisol level is 30. My T3 has decreased from 353 to 325, my T4 decreased from 1.3 to 1.1 and my TSH was 1.4 a year and a half ago. I don`t have the new results yet. My doctor also ordered a 1-123 Uptake and Scan of the thyroid. My question is: Could all of this be affecting my metabolism in some way or could it be perimenopausal causes? I`m 46 years old. Thank you for your help.
The thyroid cyst has nothing to do with your weight gain. Thyroid hormone deficiency can cause weight gain, but your normal TSH tells us that your thyroid gland is making a normal amount of thyroid hormone. Incidentally, if this next biopsy comes back inadequate for diagnosis again, many endocrinologists would recommend that you have it removed surgically. The cortisol level of 30 seems a bit high, but by itself means nothing. You either need a 24 hour urine for free cortisol, or a dexamethasone suppression test to be sure that your weight gain isn't caused by excessive cortisol secretion (this is called "Cushing's Syndrome.")
If your repeat TSH is normal and you don't have Cushing's Syndrome, then I don't think we will be able to give you a simple explanation for your weight gain. Menopause in and of itself does not cause weight gain. Certainly many people gain weight as they get older. In general, this means that they are eating more calories than their body needs to maintain their metabolic needs at their current level of exercise.
Thomas A Murphy, MD, FACP, FACE
Associate Professor of Medicine
School of Medicine
Case Western Reserve University