The results of a study of older adults suggest that people who have an under active thyroid, or hypothyroidism, but with no symptoms, have an increased the risk of congestive heart failure, but not other cardiovascular disease or death.
Asymptomatic hypothyroidism is characterized by an increased level of thyroid stimulating hormone (TSH), but a normal level of thyroxine (T4). The prevalence of this condition increases with age, Dr. Nicolas Rodondi from the University of Lausanne, Switzerland and colleagues explain in the November 28th Archives of Internal Medicine.
Asymptomatic hypothyroidism has been associated with higher levels of some cardiac risk factors but data on cardiovascular outcomes and de ath are limited, they also note.
Rodondi’s team therefore examined the risks of heart failure, coronary heart disease, stroke, peripheral artery disease and death compared with TSH levels in a 4-year study of 2,730 men and women between 70 and 79 years old.
Hypothyroidism was detected in 338 (12.4 percent) of study participants.
Compared with adults with normal thyroid function, congestive heart failure was about twice as common in patients with moderate or severe asymptomatic hypothyroidism.