Study shows cognitive function in elderly not related to thyroid disorders

A recent study published in the Journal of Clinical Endocrinology and Metabolism shows that elderly patients with subclinical hypothyroidism who received thyroxine replacement showed no improvement in cognitive function, Endocrine Today reports.

Researchers from the College of Medical and Dental Sciences at the University of Birmingham conducted a controlled study of 94 patients aged 65 years and older who had subclinical hypothyroidism. They assigned the group to daily placebo or .25 mg of thyroxine (T4) replacement for 12 months. Free thyroxine and thyroid-stimulating hormone were evaluated in 8-week increments and doses were adjusted in one-tablet increases.

After 6 months, 82 percent of patients assigned to T4 replacement achieved euthyroidism - normal levels of thyroid hormone. At 12 months, that percentage rose to 84 percent.

Results show "no improvement in cognitive function both in the short-term and after a substantial period of time has elapsed while rendered euthyroid," according to the news source.

Based on these data, thyroid dysfunction screening in elderly people should not be used if the aim is to identify those with decreased cognitive function, the researchers said.

According to statistics from the American Association of Clinical Endocrinologists, approximately 27 million Americans are experiencing a thyroid disorder. This includes the estimate that about half of these cases remain undiagnosed.