The use of thyroid hormone therapy in nonpregnant individuals with subclinical hypothyroidism was not associated with improvements in general quality of life or thyroid-related symptoms, according to study results published in JAMA.
“These findings do not support the routine use of thyroid hormone therapy in adults with subclinical hypothyroidism,” wrote the investigators.
Although subclinical hypothyroidism is common in the general population, evidence is limited and inconclusive regarding therapy, and clinical practice guidelines vary in recommendations for managing subclinical hypothyroidism.
To evaluate whether thyroid hormone therapy was beneficial in a population with subclinical hypothyroidism, the researchers conducted a meta-analysis that included 21 randomized clinical trials with a combined cohort of 2192 participants. The primary outcomes were improvements in general quality of life and thyroid-related symptoms after a minimum follow-up period of 3 months.
Thyroid hormone therapy was associated with a reduced mean thyrotropin value, lowering it into the normal reference range vs placebo/no intervention groups (0.5 to 3.7 mIU/L vs 4.6 to 14.7 mIU/L, respectively). However, treatment was not associated with any benefit regarding general quality of life (n = 796; standardized mean difference, -0.11; 95% CI, -0.25 to 0.03; I2 = 66.7%) or thyroid-related symptoms (n = 858; standardized mean difference, 0.01; 95% CI, -0.12 to 0.14; I2 = 0.0%).
Treatment was “not associated with benefit regarding general quality of life, thyroid-related symptoms, depressive symptoms, fatigue/tiredness, cognitive function, muscle strength, blood pressure, or body mass index,” the researchers concluded.
Feller M, Snel M, Moutzouri E, et al. Association of thyroid hormone therapy with quality of life and thyroid-related symptoms in patients with subclinical hypothyroidism: a systematic review and meta-analysis. JAMA. 2018;320(13):1349-1359.