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991.
OBJECTIVE: Relationship between adult growth hormone deficiency (AGHD) and increased cardiovascular disease risk is very well known in hypopituitary patients treated with conventional hormone replacement therapy other than growth hormone (GH) administration. Endothelial dysfunction, an early and reversible event in pathogenesis of atherosclerosis, is associated with increased vascular smooth muscle tone, arterial stiffening and intima-media thickness (IMT). Coronary flow reserve (CFR) measurement by transthoracic Doppler echocardiography (TTDE) reflects coronary microvascular and endothelial functions, as a cheaper and an easy screening test. We have used TTDE to evaluate endothelial function and coronary microvascular function in AGHD. DESIGN: Cross-sectional observational study. PATIENTS: A total of 10 GH-deficient adults on conventional replacement therapy other than GH (4 males, 6 females; mean age 37 +/- 11 years) and 15 healthy subjects (7 males, 8 females; mean age 41 +/- 11 years) were studied. Patients and controls were all nonsmokers, normotensive and nondiabetic. MEASUREMENTS: IGF-1, free T4, lipid profile, insulin, glucose, insulin resistance (IR), anthropometrical and physical parameters were recorded. CFR recordings and IMT measurements were performed using the Vivid 7 echocardiography device. RESULTS: IMT were significantly higher in patients than controls (0.70 + 0.19 mm and 0.53 + 0.13 mm, respectively; P = 0.02). CFR was significantly lower in patients than in controls (1.96 +/- 0.35 and 2.62 +/- 0.45, respectively; P < 0.001). CFR was positively correlated with IGF-1 levels (r = 0.54, P = 0.005). CONCLUSION: CFR is significantly lower in adults with GH deficiency than in controls. Direct correlation between CFR and IGF-1 concentrations suggests GH replacement could improve microvascular function and thereby could decrease cardiovascular morbidity and mortality in AGHD.  相似文献   
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Background

Several recent studies have suggested an increased cancer risk among patients with heart failure (HF). However, these studies are constrained by limited size and follow-up, lack of comprehensive data on other health attributes, and adjudicated cancer outcomes.

Objectives

This study sought to determine whether HF is associated with cancer incidence and cancer-specific mortality.

Methods

The study assembled a cohort from the Physicians’ Health Studies I and II, 2 randomized controlled trials of aspirin and vitamin supplements conducted from 1982 to 1995 and from 1997 to 2011, respectively, that included annual health evaluations and determination of cancer and HF diagnoses. In the primary analysis, the study excluded participants with cancer or HF at baseline and performed multivariable-adjusted Cox models to determine the relationship between HF and cancer, modeling HF as a time-varying exposure. In a complementary analysis, the study used the landmark method and identified cancer-free participants at 70 years of age, distinguishing between those with and without HF, and likewise performed Cox regression. Sensitivity analyses were performed at 65, 75, and 80 years of age.

Results

Among 28,341 Physicians’ Health Study participants, 1,420 developed HF. A total of 7,363 cancers developed during a median follow-up time of 19.9 years (25th to 75th percentile: 11.0 to 26.8 years). HF was not associated with cancer incidence in crude (hazard ratio: 0.92; 95% confidence interval: 0.80 to 1.08) or multivariable-adjusted analysis (hazard ratio: 1.05; 95% confidence interval: 0.86 to 1.29). No association was found between HF and site-specific cancer incidence or cancer-specific mortality after multivariable adjustment. Results were similar when using the landmark method at all landmark ages.

Conclusions

HF is not associated with an increased risk of cancer among male physicians.  相似文献   
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OBJECTIVE: To assess whether corpus gastritis due to Helicobacter pylori protects against erosive esophagitis in an area with high prevalence of H. pylori infection. METHODS: Biopsies obtained from gastric corpus and antrum in 151 patients with symptoms of gastroesophageal reflux disease were studied for presence of H. pylori and endoscopic evidence of gastritis. Presence and grade of esophagitis at endoscopy was recorded. RESULTS: Fifty-four (36%) patients had endoscopic esophagitis. Patients with severe esophagitis (>or= grade II) less often had active gastritis (15/45 vs. 55/98; p=0.02) and had a lower density of H. pylori (p=0.0003) than those without esophagitis. CONCLUSION: Active corpus gastritis due to H. pylori infection may protect against erosive esophagitis in patients with gastroesophageal reflux disease in the Middle East.  相似文献   
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