Hyperthyroidism or hypothyroidism may contribute to the development of systolic heart failure (SHF) or may contribute to the exacerbation of existing SFH. Current guidelines recommend a screening thyroid stimulating hormone (TSH) with the initial evaluation do the SHF patient. However the cost effectiveness of this practice is currently unknown as the prevalence of thyroid disease is associated with SHF has not been well described.
One hundred forty-seven patients referred to our indigent ambulatory SHF clinic over a three-month period were screened for thyroid perturbations with the third generation ultra-sensitive TSH assay. Patients were assigned to one of four groups according tot the assay results: group 1 (TSH<0.4 IU), group II (TSH = 0.4 -4.0 IU)— the normal range at our institution, group III (TSH>0.4 - 10.0 IU), and group IV (TSH>10.0 IU). Patients with group II (normal range) TSH presently on thyroid replacement therapy were deemed hypothyroid.RESULT: The prevalence of depressed TSH (hyperthyroid) (group I) was 1.3% and the prevalence of elevated TSH (hypothyroid) (group III &IV) was 9.5%. Six patients (4%) were on thyroid replacement therapy but all were euthyroid by assay. Including this cohort, the prevalence of hypothyroidism was 13.6%.CONCLUSIONS: In our population, an elevated TSH was uncommon but not rare. A depressed TSH was rare.
It appears that routine TSH screening is justifiable in this patient population, but further studies are warranted to evaluate the cost-effectiveness of such screening.
L.M. Arcement, None.