Levothyroxine treatment of subclinical hypothyroidism in the elderly does not improve hemoglobin levels

The debate about the clinical usefulness of treating subclinical hypothyroidism in elderly individuals is ongoing (2,3). In clinical practice, patients may commonly present with nonspecific symptoms, such as fatigue or exercise intolerance. In these cases, hypothyroidism and anemia are some of the first items to rule out in the differential diagnosis: clinicians may discover subclinical hypothyroidism and have to decide whether to treat or not with levothyroxine. An earlier meta-analysis of observational data found a clear association between subclinical hypothyroidism and anemia, both in cross-sectional and longitudinal analyses, suggesting a causal relationship (4). However, the interventional study by Du Puy et al.(1) did not confirm these data: no improvement in hemoglobin level was recorded in patients with or without anemia and with different degrees of subclinical hypothyroidism. This result is consistent with previous data from the TRUST (5) and IEMO (6) trials: levothyroxine treatment in older persons did not improve thyroid-specific and generic quality of life, grip strength, blood pressure, and body-mass index. Generally speaking, recent interventional data suggest a cautious approach to levothyroxine treatment in older individuals: benefits are indeed limited, and risks may not be negligible (7,8). Many authors suggest considering treatment only when TSH levels are greater than 7 mIU/L (3) or 10 mIU/L (2). Evidence supporting these recommendations is still weak: in the reported cohort (1), only 151 participants had TSH levels >7 mIU/L, and 21 had baseline TSH >10 mIU/L. Future studies should focus directly on individuals with higher TSH levels to have adequate statistical power to clarify this issue.