P6391Major acute cardiovascular events in patients with inflammatory bowel disease

Introduction

Traditional risk factors for coronary heart disease have been reported in around 85% patients who present with myocardial infarction. More recently, inflammation and immune mediated diseases have been associated with ischemic heart disease.

Inflammatory Bowel Disease (IBD) is an immune mediated disorder which comprises of ulcerative colitis and Crohn's disease. Estimated prevalence of IBD in the United States in 2004 was 1.4 million people. These patients have an overall increased risk of thrombotic complications with microvascular thrombosis hypothesized to contribute in disease pathogenesis.

Results from a recent meta-analysis were consistent with increased risk of ischemic heart disease among IBD patients, with risk greater in females and younger patients, although heterogeneity was considerable in overall data. Also, in a recent study, IBD was found to be associated with an increased risk of acute myocardial infarction and heart failure despite lower prevalence of coronary risk factors in IBD patients.

IBD pathogenesis involves sustained activation of immune responses with upregulation of cytokines including but not limited to IL-1 beta, IL-6 and TNF-alpha. Upregulation of these cytokines has also been reported in coronary atherosclerosis.

Based on above information, we explored incidence of MACE (Major Adverse Cardiac Event) in this patient population from our health system data-base.

Methods

Propensity scores were estimated for all 15,292 (0.4%) patients with inflammatory bowel disease from a total patient pool of 3,917,894 patients in our health system to assemble a 1:1 matched cohort balanced for age, gender, race and known cardiovascular risk factors including hypertension, hyperlipidemia, diabetes mellitus and smoking (current and former). ICD-9 and ICD-10 codes were used to identify cardiovascular risk factors and outcomes.

Results

Matched patients (n=30,584) had a mean age of 51 years, with 58% of all being women, and 63% Caucasian. During the median follow up of 4.4 years all-cause mortality was observed in 1.7% and 1.2% of patients from IBD and non-IBD groups respectively (hazard ratio {HR}, 1.31; 95% confidence interval {CI}, 1.08–1.58; p=0.005). Combined outcome for myocardial infarction or all-cause mortality was noted in 4.1% and 3.4% from IBD and non-IBD groups respectively (HR, 1.16; 95% CI, 1.03–1.30; p=0.014) while HRs for cardiovascular mortality, myocardial infarction and unstable angina independently were 1.04 (0.74–1.47; p=0.833), 1.05 (0.89–1.23; p=0.591) and 1.10 (0.83–1.46; p=0.524) respectively.

Conclusion

Inflammatory bowel disease did not show association with myocardial infarction, cardiovascular mortality or unstable angina when matched for known cardiovascular risk factors, but was associated with increased all-cause mortality and combined end-point of all-cause mortality or myocardial infarction.

Effect of lead concentration on the level of glutathione, glutathione S-transferase, reductase and peroxidase in human blood

Incubation of human whole blood for 24 h at 37 degrees C in the presence of 100-400 microg/dl lead chloride or lead acetate caused a concentration-dependent decrease in the level of reduced glutathione up to 40%. Similarly, the activities of glutathione reductase, glutathione peroxidase and glutathione S-transferase were decreased up to 25%, 50%, and 19%, respectively. Moreover, 100 microg/dl lead chloride or lead acetate slowed the process of glutathione regeneration, and delayed the time for complete regeneration from 20 to 40 min. When glutathione S-transferase was purified by affinity chromatography on Sepharose-linked glutathione, incubated with lead chloride or lead acetate, a concentration-dependent inhibition of the enzymatic activity was observed reaching 50% inhibition at a lead salt concentration of 6000 microg/dl.

Lead concentration and the level of glutathione, glutathione S-transferase, reductase and peroxidase in the blood of some occupational workers from Irbid City, Jordan

Blood samples were collected from 263 lead-exposed suspected males living in Irbid area in the northern part of Jordan. The blood lead concentrations in the samples were determined by atomic absorption and were related to the type of work performed by the workers. The blood lead concentration was higher in metal casters, 41.6, and radiator welders, 32,8 micrograms/dl, compared to non-suspected lead-exposed university students, 5.7 micrograms/dl. Workers such as mechanics, bus drivers, car painters and gas station workers showed slightly higher but not significant blood lead. The blood glutathione content and the activities of glutathione reductase, glutathione peroxidase and glutathione S-transferase were also determined in non-suspected subjects and in those with occupational exposure to lead. With increasing blood lead concentration, glutathione content decreases as well as the activities of the glutathione utilizing enzymes.