Endocrine Abstracts

Up to 90% of patients treated with radioactive iodine treatment for hyperthyroidism develop hypothyroidism, in some cases many years after treatment. The majority of patients receiving RI in our clinic were referred from clinics throughout the northwest of England and attend on one occasion for RI treatment with follow-up by the referring physician. The Royal College of Physicians guidelines recommend centres administering RI have a system for regular patient monitoring to identify hypothyroidism. The aim of the study was to assess the need for such a follow-up system by determining the follow-up status of the 317 patients (mean age 57 years, range 15-88 ) treated with RI for hyperthyroidism in 1991. Questionnaires were sent to patients and their GPs. 170 (54%) patients were under continuing follow-up with their GP and 89 (28%) had died. 58 (18%) patients were no longer with the GP and could not be traced. 78% (132 of 170) of patients were known to be hypothyroid 10 years after RI (median dose 250 MBq, range 112-799) treatment. In conclusion, in the absence of an automated follow-up system, 10 years after treatment, 18% of patients had been lost to follow-up and are at risk of unrecognised hypothyroidism.