Biomedical subjects

Chul Ahn

Publications and source records attributed to Chul Ahn.

43 records · Page 3Linked to original sources

PubMed2002

Prevalence and association of ventricular tachycardia and complex ventricular arrhythmias with new coronary events in older men and women with and without cardiovascular disease.

BACKGROUND: We report the prevalence of ventricular tachycardia (VT) and of complex ventricular arrhythmias (VA) and their association with new coronary events in older men and women. METHODS: The prevalence of VT and of complex VA detected by 24-hour ambulatory electrocardiograms and the incidence of new coronary events in older persons with coronary artery disease (CAD), with hypertension, valvular disease, or cardiomyopathy without CAD, and with no cardiovascular disease was investigated in 915 men (mean age 80 +/- 8 years) and in 1,874 women (mean age 81 +/- 8 years) in a long-term health care facility. Follow-up was 45 +/- 30 months in men and 47 +/- 30 months in women. RESULTS: The prevalence of VT was 16% in men and 15% in women with CAD, 9% in men and 8% in women with hypertension, valvular disease, or cardiomyopathy without CAD, and 3% in men and 2% in women with no cardiovascular disease. The prevalence of complex VA was 69% in men and 68% in women with CAD, 54% in men and 55% in women with hypertension, valvular disease, or cardiomyopathy without CAD, and 31% in men and 30% in women with no cardiovascular disease. In men and in women with CAD or with hypertension, valvular disease, or cardiomyopathy, VT and complex VA increased the incidence of new coronary events (p <.0001). Within each of the groups of patients, the incidences of new coronary events in men and in women with and without VT or complex VA were similar. CONCLUSIONS: The prevalence of VT and of complex VA were similar in older men and women. VT and complex VA were associated with a higher incidence of new coronary events in men and women with CAD or with hypertension, valvular disease, or cardiomyopathy without CAD, but not in men and women with no cardiovascular disease.

Aged↗

PubMed2002

Incidence of new atherothrombotic brain infarction in older persons with prior myocardial infarction and serum low-density lipoprotein cholesterol >or=125 mg/dl treated with statins versus no lipid-lowering drug.

BACKGROUND: We report the incidence of new atherothrombotic brain infarction (ABI) in older men and women with prior myocardial infarction and a serum low-density lipoprotein (LDL) cholesterol of >or=125 mg/dl treated with statins and with no lipid-lowering drug. METHODS: The incidence of new ABI was investigated in an observational prospective study of 1410 men and women, mean age 81 +/- 9 years, with prior myocardial infarction and a serum LDL cholesterol of >or=125 mg/dl treated with statins (679 persons or 48%) and with no lipid-lowering drug (731 persons or 52%). Follow-up was 36 +/- 21 months. RESULTS: At follow-up, the stepwise Cox regression model showed that significant independent predictors of new ABI were age (risk ratio = 1.04 for a 1-year increase in age), cigarette smoking (risk ratio = 3.5), hypertension (risk ratio = 3.1), diabetes mellitus (risk ratio = 2.3), initial serum LDL cholesterol (risk ratio = 1.01 for each 1 mg/dl increase), initial serum high-density lipoprotein cholesterol (risk ratio = 0.97 for each 1 mg/dl increase), prior stroke (risk ratio = 2.5), and use of statins (risk ratio = 0.40). The Cochran-Armitage test showed a trend in the reduction of new ABI in persons treated with statins as the level of serum LDL cholesterol decreased ( p <.0001). CONCLUSIONS: Use of statins caused a 60%, significant, independent reduction in new ABI in older men and women with prior myocardial infarction and a serum LDL cholesterol of >or=125 mg/dl.

Aged↗

PubMedDate not supplied

Reduction of coronary events with aspirin in older patients with prior myocardial infarction treated with and without statins.

In an observational prospective study of 1,410 patients (mean age, 81 +/- 9 years) with prior myocardial infarction, no contraindications to aspirin, and a serum low-density lipoprotein cholesterol level of 125 mg/dL or higher, 832 (59%) were treated with aspirin. At the 36-month follow-up evaluation, the incidence of new coronary events was 52% in persons treated with aspirin versus 70% in those who were not treated with aspirin (P < 0.0001). The stepwise Cox regression model showed that significant independent predictors of new coronary events were age (risk ratio, 1.05 for each 1-year increase), current cigarette smoking (risk ratio, 2.7), hypertension (risk ratio, 1.7), diabetes mellitus (risk ratio, 2.2), initial serum low-density lipoprotein cholesterol level (risk ratio, 1.01 for each 1-mg/dL increase), initial serum high-density lipoprotein cholesterol level (risk ratio, 0.96 for each 1-mg/dL increase), use of statins (risk ratio, 0.46), and use of aspirin (risk ratio, 0.48).

Aged↗

PubMedDate not supplied

Prevalence of left ventricular hypertrophy in persons with and without obstructive sleep apnea.

We investigated the prevalence of left ventricular hypertrophy (LVH) in persons with and without obstructive sleep apnea (OSA). Fifty-three persons had a nocturnal polysomnogram to diagnose OSA and 2-dimensional echocardiograms to measure left ventricular mass. OSA was considered mild if the respiratory disturbance index (RDI) was 5 to 15, moderate if the RDI was 15 to 30, and severe if the RDI was >30. LVH was diagnosed if the left ventricular mass index was >110 g/m in women and >134 g/m in men. LVH was present in 21 of 27 persons (78%) with moderate or severe OSA, in 6 of 13 persons (46%) with mild OSA, and in 3 of 13 persons (23%) with no OSA (P < 0.001 comparing moderate or severe OSA with no OSA and P < 0.05 comparing moderate or severe OSA with mild OSA). OSA was a significant independent predictor of LVH after controlling the confounding effects of hypertension with an odds ratio of 3.579 (95% confidence interval, 1.589-8.058).

Adult↗

PubMedDate not supplied

Association of diet alone, insulin, sulfonylureas, metformin, and thiazolidinediones with the severity of coronary artery disease in patients with diabetes mellitus.

Coronary angiography was performed in 152 men and 163 women with diabetes mellitus, mean age 55 +/- 8 years, because of chest pain. Of 67 patients with 3-vessel or 4-vessel coronary artery disease (CAD), 17 (25%) were treated with diet alone, 29 (43%) with insulin, 18 (27%) with sulfonylureas, 12 (18%) with metformin, and 6 (9%) with thiazolidinediones. Of 76 patients with 2-vessel CAD, 20 (26%) were treated with diet alone, 36 (47%) with insulin, 21 (28%) with sulfonylureas, 21 (28%) with metformin, and 11 (14%) with thiazolidinediones. Of 40 patients with 1-vessel CAD, 15 (38%) were treated with diet alone, 11 (28%) with insulin, 8 (20%) with sulfonylureas, 12 (30%) with metformin, and 4 (10%) with thiazolidinediones. Of 132 patients with 0-vessel CAD, 18 (14%) were treated with diet alone, 21 (16%) with insulin, 7 (5%) with sulfonylureas, 75 (56%) with metformin, and 35 (26%) with thiazolidinediones. Cochran-Armitage trend tests were used to examine whether the use of treatment significantly increases or decreases as the number of arteries with CAD increases (P = 0.036 for diet alone; P < 0.0001 for insulin, for sulfonylureas, and for metformin; P = 0.002 for thiazolidinediones).

Aged↗

PubMedDate not supplied

Increased fasting plasma insulin concentrations are associated with the severity of angiographic coronary artery disease.

Fasting plasma insulin concentrations were obtained in 82 patients (51 men and 31 women), mean age 60 +/- 11 years, with a body mass index >25 kg/m(2) who had coronary angiography because of suspected symptomatic coronary artery disease (CAD). Obstructive CAD was diagnosed if there was >50% obstruction of > or =1 vessel. Of 82 patients, 37 (45%) had left main or 3-vessel CAD, 22 (27%) had 2-vessel CAD, 9 (11%) had 1-vessel CAD, and 14 (17%) had no obstructive CAD. Among the 4 groups, there was no significant difference in gender, age, dyslipidemia, and smoking. Hypertension (p = 0.0003), diabetes mellitus (p = 0.035), and increased fasting plasma insulin concentration (p < 0.0001) were significantly associated with the severity of CAD. Stepwise ordinal logistic regression analysis identified increased fasting plasma insulin concentrations in these obese subjects as a significant independent risk factor for the severity of angiographic CAD (p < 0.0001).

Coronary Angiography↗

PubMedDate not supplied

Choline deficiency is associated with increased risk for venous catheter thrombosis.

BACKGROUND: Patients with intestinal failure who require long-term parenteral nutrition (PN) develop catheter thrombosis as a complication. This patient group may also develop choline deficiency because of a defect in the hepatic transsulfuration pathway in the setting of malabsorption. This study was undertaken to determine whether choline deficiency is a risk factor for development of catheter thrombosis. METHODS: Plasma free and phospholipid-bound choline concentrations were measured in a group of 41 patients that required long-term PN. Episodes of catheter thrombosis from onset of PN to the time of blood testing were recorded. RESULTS: Sixteen (39%) patients developed catheter thrombosis, and 5 of these had recurrent catheter thrombosis. Plasma free choline was 7.7 +/- 2.7 nmol/mL in patients with no history of catheter thrombosis and 6.2 +/- 1.7 nmol/mL in patients with previous catheter thrombosis (p = .076 by Wilcoxon rank-sum test). The partial correlation between plasma free choline concentration and the frequency of clots after controlling for catheter duration was r = -0.33 (p = .038). The relative risk for catheter thrombosis in subjects with a plasma free choline concentration <8 nmol/mL was 10.0, 95% confidence interval (1.134-88.167). Plasma phospholipid-bound choline concentration was 2191.7 +/- 679.0 nmol/mL in patients with previous catheter thrombosis and 2103.3 +/- 531.2 nmol/mL in patients without history of catheter thrombosis (p = NS). CONCLUSION: Choline deficiency is a significant risk factor for development of catheter thrombosis in patients with intestinal failure who require PN.

Adult↗