Risk factors for silent myocardial ischemia in patients with well-controlled essential hypertension.

Silent myocardial ischemia (SMI) is frequently observed in patients with essential hypertension (EH). The major risk factor for SMI is uncontrolled blood pressure (BP), but SMI is also observed in patients with well-controlled BP. To evaluate the prevalence of SMI and the factors associated with SMI in EH patients with well-controlled BP. The medical records of 859 EH patients who underwent simultaneous 24-h ambulatory blood pressure monitoring (ABPM) and 24-h ambulatory electrocardiogram recording (AECG) were retrospectively evaluated. Each SMI episode was characterized by: (a) ST segment depression ≥0.5 mm; (b) duration of ST segment depression >60 s; and (c) reversibility of the ST segment depression. Overall 126 EH patients (14.7 %) had at least one episode of SMI. The SMI events were more frequent among patients with poorly controlled compared to those with well-controlled BP [86/479 (17.95 %) vs. 40/380 (10.52 %), p < 0.01]. Among EH patients with well-controlled BP, current and past smoking as well as the presence of an additional metabolic syndrome (MetS) constitutive element (obesity, impaired fasting glucose level or dyslipidemia) were significantly associated with the occurrence of SMI. In all EH patients with well-controlled BP and AECG evidence of SMI, there were one or more coronary artery stenotic lesions greater than 50 % found at coronary angiography. In EH patients who are current smokers, or have one or more additional components of a MetS there is markedly reduced benefit associated with good BP control with regard to the occurrence of myocardial ischemia: in this patient category, an AECG may help detect this condition.

Recombinant Human Thyrotropin Improves Endothelial Coronary Flow Reserve in Thyroidectomized Patients with Differentiated Thyroid Cancer.

BACKGROUND: The role of thyrotropin (TSH) on the cardiovascular system has been poorly investigated. It is unknown whether the changes in the vasculature associated with thyroid diseases result from altered thyroid hormone action or whether they are a consequence of a direct effect of TSH on endothelial cells. The present study was designed to evaluate the endothelial response of coronary flow to TSH in patients with differentiated thyroid cancer (DTC) without cardiovascular risk factors. METHODS: The study population consisted of three men and seven women (Mage = 32.6 ± 8 years) who underwent total thyroidectomy for DTC. All were receiving therapy with L-thyroxine to maintain TSH within the reference range. No patient was obese, or had hypertension, diabetes, or dyslipidemia. Patients underwent standard echo-Doppler examination with evaluation of the coronary flow reserve (CFR) of the distal left anterior descending artery obtained by cold pressure test (CPT) before and 24 h after the second recombinant human TSH (rhTSH) injection. RESULTS: Left ventricular morphology and systolic and diastolic function were normal in all patients. Levels of thyroid hormones and thyroglobulin and antithyroglobulin antibodies did not differ significantly pre- versus post-rhTSH treatment, whereas TSH levels were higher after rhTSH administration. Blood pressure and heart rate were not affected by rhTSH. Coronary flow peak velocity at rest (22.3 ± 6 vs 23.2 ± 8.7; p = 0.66) did not differ between baseline and 24 h after rhTSH, while post-CPT velocity (29.3 ± 6.8 vs 34.4 ± 10.9; p < 0.05) and the CFR were higher after rhTSH administration (1.32 ± 0.2 vs. 1.53 ± 0.2; p < 0.01). CONCLUSIONS: rhTSH administration may improve the CFR after the non-pharmacological stressor CPT in DTC patients. The increase of coronary blood flow after rhTSH suggests that TSH may exert a protective effect on the coronary endothelium.

Habitual salt intake and risk of gastric cancer: a meta-analysis of prospective studies.

BACKGROUND & AIMS: Systematic reviews of case-control studies evaluating the relationship between dietary salt intake and gastric cancer showed a positive association, however a quantitative analysis of longitudinal cohort studies is lacking. Therefore, we carried out a meta-analysis to assess the association between habitual salt intake and risk of gastric cancer in prospective studies. METHODS: We performed a systematic search of published articles (1966-2010). Criteria for inclusion were: original articles, prospective adult population studies, assessment of salt intake as baseline exposure and of gastric cancer as outcome, follow-up of at least 4 years, indication of number of participants exposed and events across different salt intake categories. RESULTS: Seven studies (10 cohorts) met the inclusion criteria (268 718 participants, 1474 events, follow-up 6-15 years). In the pooled analysis, "high" and "moderately high" vs "low" salt intake were both associated with increased risk of gastric cancer (RR = 1.68 [95% C.I. 1.17-2.41], p = 0.005 and respectively 1.41 [1.03-1.93], p = 0.032), with no evidence of publication bias. The association was stronger in the Japanese population and higher consumption of selected salt-rich foods was also associated with greater risk. Meta-regression analyses did not detect specific sources of heterogeneity. CONCLUSIONS: Dietary salt intake was directly associated with risk of gastric cancer in prospective population studies, with progressively increasing risk across consumption levels.