Masked hypertension in newly diagnosed hypothyroidism: a pilot study.

PURPOSE: Masked hypertension (MH) is the association of normal office blood pressure (BP) with high ambulatory or home BP. This condition is associated with increased cardiovascular target organ damage, as true hypertension. Because the relation with hypothyroidism is controversial, we investigated it in a pilot longitudinal and controlled study. METHODS: We consecutively enrolled 64 newly diagnosed hypothyroid patients, 38 subclinical (s-HYPO), and 26 overt (o-HYPO). The control group consisted of 50 euthyroid subjects seen at outpatient clinics. All participants underwent office and 24-h ambulatory BP measurement. RESULTS: BP monitoring revealed a higher prevalence of MH both in s-HYPO (26.3 %) and in o-HYPO (15.4 %) than in euthyroid subjects (10 %, p = 0.05); true hypertension also was more frequent in o-HYPO (11.5 %) and s-HYPO (10.5 %) than in controls (8 %, p = 0.03). The odds ratio for hypertension versus normotension confirmed a significantly increased risk of MH in hypothyroid patients versus euthyroid subjects (3.29, 1.08-10.08; p = 0.02). In a subgroup of patients reevaluated after restoration of euthyroidism, an improvement of BP profile was observed, especially in s-HYPO subgroup, with a decreased prevalence of MH (from 25 to 10.7 %) and true hypertension (from 10.7 to 3.4 %). CONCLUSIONS: Hypothyroidism may be an important predictor of higher BP values, with an increased risk of MH. Because MH is a cardiovascular risk and can be reversed by thyroid hormone replacement, its presence should represent an indication for thyroid hormone replacement therapy also in patients with s-HYPO.

Prevalence and natural history of Graves' orbitopathy in a large series of patients with newly diagnosed graves' hyperthyroidism seen at a single center.

BACKGROUND: The prevalence and natural history of Graves' orbitopathy (GO) are poorly documented. METHODS: A large series of 346 patients with newly diagnosed and recent onset Graves' hyperthyroidism seen at a single (nontertiary referral) center over an 8-year period were enrolled in an observational prospective study and evaluated for GO activity and severity according to the EUGOGO (European Group on Graves' Orbitopathy) criteria. After excluding patients immediately treated for moderate-to-severe GO, patients undergoing total thyroidectomy or radioactive iodine treatment, and patients lost to follow-up, 237 patients were submitted to antithyroid drug (ATD) treatment, with ocular evaluation at 6, 12, and 18 months. RESULTS: Among the whole cohort, at presentation 255 (73.7%) had no ocular involvement, 70 (20.2%) had mild and inactive GO, 20 (5.8%) had moderate-to-severe and active GO, and 1 (0.3%) had sight-threatening GO with dysthyroid optic neuropathy. Of the 237 patients who completed the 18-month follow-up during or after ATD treatment, 194 (81.9%) had no GO at baseline. Progression to moderate-to-severe GO occurred in 5 (2.6%) of these patients. Of the 43 (18.1%) patients with mild and inactive GO at baseline, 1 (2.4%) progressed to moderate-to-severe GO, and 25 (58.1%) experienced complete remission. CONCLUSIONS: Most patients with newly diagnosed Graves' disease have no ocular involvement. Moderate-to-severe and active GO or sight-threatening GO are rare at presentation and rarely develop during ATD treatment. Most patients (>80%) with no GO at baseline do not develop GO after an 18-month follow-up period. Remission of mild GO occurs in the majority of cases.

Thyroid autoimmunity and environment.

Autoimmune thyroid disorders (AITDs) are the result of a complex interplay between genetic and environmental factors, the former account for about 70-80% of liability to develop AITDs. However, at least 20-30% is contributed by environmental factors, which include certainly smoking (at least for Graves' disease and orbitopathy), probably stress, iodine and selenium intake, several drugs, irradiation, pollutants, viral and bacterial infections, allergy, pregnancy, and post-partum. Evidence for the intervention of these factors is often limited, and the mechanisms whereby environmental factors may concur to the onset of AITDs are in many instances unclear. Nevertheless, gene-environment interaction seems a fundamental process for the occurrence of AITDs.