| Allahabadia et al., Birmingham, UK, retrospectively analyzed results of I-131 treatment of 800 consecutive patients with hyperthyroidism. Cure was defined as euthyroidism for 6 months or hypothyroidism. There was no difference in cure rate between Graves' disease (GD) and toxic nodular goiter (TNG) (70.4% vs. 69.4%, p = NS). GD patients had higher incidence of hypothyroidism (79% vs. 41%, p < 0.001). Patients with solitary nodules had a higher cure rate than with TNG (77% vs 59%, p = 0.03). The use of antithyroid drugs before or after radioiodine vs no antithyroid drugs, was associated with a lower cure rate (72% vs 80%, p = 0.04). Males had lower cure rates than females (67% vs 77%, p < 0.01). Patients < 40 years had lower cure rates than > 40 years (69.6% vs 79%, p < 0.01) and had a higher incidence of hypothyroidism (75% vs 64%, p < 0.01). Patients with more severe hyperthyroidism and with palpable goiter/nodules were less likely to be cured after one dose I-131, p < 0.0001. Administration of 400 MBq resulted in a higher cure rate as compared to 200 MBq (83% vs 68%, p < 0.0001), but a higher incidence of hypothyroidism at one year (73% vs 63%, p < 0.01). (Comment: The authors conclude that administration of 400 MBq I-131 is highly effective. I fully agree with this and also with the policy of the authors not to give I-131 adjusted to type of hyperthyroidism, size of goiter, and 24h thyroidal I-131 uptake. This regimen has never proven to be of real benefit with regard to achieving cure. Furthermore the adjusted regimen is costly, patient unfriendly, and therefore is to be discouraged.) Woodmansee et al., Denver, CO, USA, examined changes in energy expenditure in 10 patients with overt hyperthyroidism (OH) and 17 with subclinical hyperthyroidism (SH) and compared results to healthy controls. There were no differences in lean body mass measured by DEXA between the three groups. OH patients had higher 24 hour energy expenditures (24 EE) than SH patients and controls, as measured by calorimetry: mean values were 2813.7 kcal/d, 2298 kcal/d, and 2045 kcal/d respectively. When adjusted for lean body mass 24 EE was significantly higher in OH vs the two other groups. In SH this value tended to be different from controls (p = 0.06). Exercise capacity (VO2max) were reduced in both patients groups vs controls. The authors suggest that not only in patients with OH but also SH derangements are present of energy expenditure and exercise capacity. (Comment: Although 24 EE corrected for lean body mass just did not reach the level of significance in patients with SH, the trend towards a real difference is certainly there. The results of this study are an additional reason to seriously consider treatment of patients with SH.) |
