TREATMENT OF SUBCLINICAL HYPERTHYROIDISM: EFFECT ON BODY COMPOSITION

Area of Science:

• Endocrinology
• Nuclear Medicine
• Geriatrics

Background:

• Subclinical hyperthyroidism (SHT) poses risks to cardiovascular health, bone metabolism, and can progress to overt hyperthyroidism.
• Weight loss is common in overt hyperthyroidism, particularly impacting elderly patients.

Purpose of the Study:

• To evaluate changes in body composition following radioiodine therapy for SHT caused by toxic nodular goiter.

Main Methods:

• A prospective controlled cohort study compared radioiodine treatment versus delayed treatment for persistent SHT.
• Body composition (lean mass, fat mass, bone mineral content) was assessed using dual-energy X-ray absorptiometry (DEXA) at baseline and 12 months.
• The study included 29 patients (17 treated, 12 controls), with a focus on individuals over 65 years old.

Main Results:

• No significant changes in body composition were observed in the overall cohort, except for a trend towards increased fat mass.
• In patients over 65, radioiodine therapy resulted in significant increases in body weight, BMI, fat mass, lean mass, and skeletal muscle mass index (SMI).

Conclusions:

• Radioiodine therapy for SHT positively impacts body composition in individuals older than 65.
• The observed weight gain in older patients is attributed to increases in both fat and lean mass, suggesting a beneficial effect on muscle health.