Relação entre Hipotiroidismo Subclínico e Doença Coronária: um Estudo com Angiografia

INTRODUCTION: The definition of subclinical hypothyroidism (SH) is an asymptomatic state in which free thyroxine (T4) is normal and thyroid-stimulating hormone (TSH) levels are elevated. Its relationship with coronary disease is not clear and has been the subject of recent interest. Current evidence is conflicting and there is a lack of studies supported by coronary angiography. OBJECTIVE: To assess the relationship between SH and the presence and extent of coronary disease diagnosed by angiography. METHODS: We prospectively studied 354 consecutive patients referred for elective coronary angiography. Those with known thyroid disease, documented coronary disease or previous myocardial infarction were excluded. Fasting blood specimens were collected to measure thyroid hormones, lipid profile, high-sensitivity C-reactive protein, fibrinogen and NT-proBNP. Patients with SH were compared with those without to assess differences in clinical characteristics and biochemical and angiographic results. Significant coronary disease was defined as the presence of at least one lesion with > or = 50% luminal stenosis. Lesions with <50% stenosis were considered minimal. RESULTS: SH was diagnosed in 32 (9%) patients. Mean age was similar between the groups. There were more women (66% vs. 39%; p=0.003) and atrial fibrillation was more frequent (25% vs. 11%; p=0.016) in the group of patients with SH. There were no significant differences in the other baseline clinical parameters, and blood biochemistry results were similar in the two groups, with the exception of higher levels of NT-proBNP in SH patients, although without statistical significance. The angiographic results were as follows: significant coronary disease (SH 28.1% vs. non-SH 43.8%; p=0.087); three-vessel disease (9.4% vs. 9.9%; p=0.919); two-vessel disease (12.5% vs. 13.4%; p=0.892); single-vessel disease (6.3% vs. 29.5%; p=0.051); minimal lesions (9.4% vs. 10.9%; p=0.794); and no coronary disease (62.4% vs, 45.3%; p=0.064). CONCLUSION: In this population SH was not associated with the presence or extent of coronary disease diagnosed by coronary angiography.

Intraocular Pressure Correlates with Optic Nerve Sheath Diameter in Patients with Normal Tension Glaucoma

PURPOSE: 1. Identify differences in optic nerve sheath diameter (ONSD) as an indirect measure of intracranial pressure (ICP) in glaucoma patients and a healthy population. 2. Identify variables that may correlate with ONSD in primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) patients. METHODS: Patients with NTG (n = 46) and POAG (n = 61), and healthy controls (n = 42) underwent B-scan ultrasound measurement of ONSD by an observer masked to the patient diagnosis. Intraocular pressure (IOP) was measured in all groups, with additional central corneal thickness (CCT) and visual field defect measurements in glaucomatous patients. Only one eye per patient was selected. Kruskal-Wallis or Mann-Whitney were used to compare the different variables between the diagnostic groups. Spearman correlations were used to explore relationships among these variables. RESULTS: ONSD was not significantly different between healthy, NTG and POAG patients (6.09 ± 0.78, 6.03 ± 0.69, and 5.71 ± 0.83 respectively; p = 0.08). Visual field damage and CCT were not correlated with ONSD in either of the glaucoma groups (POAG, p = 0.31 and 0.44; NTG, p = 0.48 and 0.90 respectively). However, ONSD did correlate with IOP in NTG patients (r = 0.53, p < 0.001), while it did not in POAG patients and healthy controls (p = 0.86, p = 0.46 respectively). Patient's age did not relate to ONSD in any of the groups (p > 0.25 in all groups). CONCLUSIONS: Indirect measurements of ICP by ultrasound assessment of the ONSD may provide further insights into the retrolaminar pressure component in glaucoma. The correlation of ONSD with IOP solely in NTG patients suggests that the translaminar pressure gradient may be of particular importance in this type of glaucoma.