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Y Liao

Publications and source records attributed to Y Liao.

At least 145 records · Page 8Linked to original sources
PubMed1994

Iron status and coronary heart disease: negative findings from the NHANES I epidemiologic follow-up study.

The potential association between iron status and coronary heart disease has received increased attention recently. The authors examine this hypothesis in the First National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-up Study. The study consisted of 4,237 respondents (1,827 men, 2,410 women) aged 40-74 years at baseline. During the average 13-year follow-up, 489 persons (289 men, 200 women) had an acute myocardial infarction, and 1,151 persons (633 men, 518 women) developed coronary heart disease (included myocardial infarction and other forms of chronic ischemic heart disease). In logistic regression analyses, adjusting for baseline age, systolic blood pressure, serum cholesterol, smoking status, and education, serum iron was inversely associated with the risk of myocardial infarction in women (relative risk = 0.82 for an increase of 5.4 mumol/liter (equivalent to about 1 standard deviation), 95% confidence interval (CI) 0.70-0.95), but not in men. Total iron-binding capacity and transferrin saturation were not related to myocardial infarction in either sex, while serum iron and transferrin saturation were inversely associated with coronary heart disease in both sexes. Among men, the relative risk was 0.92 (95% CI 0.85-1.00) for a 5.4-mumol/liter increase in serum iron, while a relative risk of 0.91 (95% CI 0.83-1.00) was observed for a 10% increase in transferrin saturation. For women, the corresponding relative risks were 0.86 (95% CI 0.77-0.95) and 0.88 (95% CI 0.79-0.98), respectively. Dietary iron intake based on 24-hour recall was not associated with the two disease end points. These findings from a large national sample do not support the hypothesis of a positive iron-coronary heart disease relation.

Adult↗
PubMed1994

Assessment of the intestinal retention of beta-carotene in humans.

OBJECTIVE: Assessment of the intestinal absorption of beta-carotene (BC) in humans as well as plasma clearance of BC has been difficult. We have used the total gut washout method (TGWM) to assess BC retention during transit through the intestine, as well as the effect that different diets and age have on BC retention. METHODS: HPLC was used to quantitate fecal and serum BC concentrations from young and elderly subjects who had undergone the TGWM to remove all intestinal contents prior to ingesting BC or placebo with or without a meal. Meals contained different combinations of calories and fat. RESULTS: In subjects receiving no meal, 83% of ingested BC was recovered in rectal effluent collected within 24 hours post-BC administration. The quantity of BC in feces of individuals receiving meals was 49-71%. There was no significant change in serum concentrations of other carotenoids or retinoids following consumption of BC with any of the different meals. Interestingly, both diet and age influenced the efficiency of BC absorption. An increase in dietary fat content resulted in an higher serum BC concentration in young subjects within 8 and at 24 hours post BC administration, whereas a higher caloric content resulted in a decrease in serum BC concentration in older subjects within 8 hours of BC administration. CONCLUSION: Results indicate that the TGWM provides an accurate means for assessing the intestinal retention of BC in humans.

Adolescent↗
PubMed1994

Factors related to the presence of microalbuminuria in essential hypertension.

The objective of the present study was to assess factors related to the presence of microalbuminuria in essential hypertension. Ninety-five patients with essential hypertension (58 males and 37 females, mean age 38.6 +/- 6.1 years) who had never been treated previously for hypertension were included in the study. Patients with nephropathy or diabetes mellitus, hyperglycemia > 120 mg/dL, glomerular filtration rate < 80 mL/min/1.73 m2, urinary tract infection, or positive dipstick for albumin or glucose were excluded. Blood pressure, echocardiographically determined left ventricular mass, serum biochemistry, and lipid profile were obtained. Twenty-four-hour urinary albumin excretion (UAE) was measured on two separate days using an immunonephelometric assay. Microalbuminuria (UAE 30 to 300 mg/24 h) occurred in 26% of patients and was associated with higher diastolic blood pressure (DBP), left ventricular mass index (LVMI), and a higher prevalence of hypertriglyceridemia and hyperapolipoproteinemia B (apo-B). Logistic regression analysis showed that the risk of microalbuminuria was independently related to diastolic blood pressure and hypertriglyceridemia when controlling for age, sex, body mass index, LVMI, and apo-B. Multiple regression analysis likewise confirmed that both DBP and LVMI were linearly related to UAE independent of age, sex, body mass index, total cholesterol, triglycerides, and apo-B. In conclusion, our study indicates that among hypertensive patients with elevated excretion rates of urinary albumin, even at the subclinical level, an increased cardiovascular risk exists compared to normoalbuminuric patients with a similar blood pressure. Assessment of the presence of microalbuminuria may be useful in the evaluation and management of hypertension.

Adult↗
PubMed1994

Intracoronary ultrasound assessment of morphological and functional abnormalities associated with cardiac allograft vasculopathy.

BACKGROUND: The diffuse nature of cardiac allograft vasculopathy makes early detection of the disease by traditional noninvasive methods or coronary angiography difficult. The aim of this study was to determine if there is a relation between abnormalities in vessel wall morphology, as assessed by intracoronary ultrasound, and a decreased vasodilatory response to the endothelium-dependent vasodilator papaverine hydrochloride and if cardiac allograft vasculopathy detected by coronary angiography is associated with specific intracoronary ultrasound findings. METHODS AND RESULTS: Twenty-three heart transplant recipients underwent 25 intracoronary ultrasound studies and 24 studies of coronary vasomotor tone 10 days to 8.3 years after surgery using a 20-mHz intracoronary ultrasound catheter. The studies were divided in two groups according to the presence (n = 7, group 1) or absence (n = 18, group 2) of angiographically evident cardiac allograft vasculopathy. Qualitative assessment of vessel wall morphology and quantitative analysis of the vasodilator response to the injection of papaverine hydrochloride into the coronary artery distal to the imaging site were performed off-line, and results for the two study groups were compared. A significantly higher percentage of patients with than without angiographic evidence of cardiac allograft vasculopathy had a three-interface vessel wall morphology by intracoronary ultrasound (100% versus 11%, P < .001). In two recipients who underwent two serial studies, the appearance of three interfaces in the vessel wall or a progressive thickening of the inner interface of the vessel wall occurred in conjunction with the appearance of angiographic cardiac allograft vasculopathy. The vasodilator response to papaverine was less in patients with than in those without angiographically evident cardiac allograft vasculopathy both in terms of absolute and relative increases in lumen diameter (+0.1 +/- 0.12 mm versus +0.3 +/- 0.17 mm, P < .05, and +5.1 +/- 5.3% versus +8.2 +/- 5.3%, P = NS) and lumen cross-sectional area (+0.5 +/- 0.6 mm2 versus +1.7 +/- 1.1 mm2, P < .02, and +7.1 +/- 8.8% versus 16.6 +/- 11.0%, P = .055), respectively. CONCLUSIONS: Intracoronary ultrasound assessment of vessel wall morphology and evaluation of vascular response to endothelium-dependent vasodilators are useful techniques for detecting cardiac allograft vasculopathy.

Cardiac Catheterization↗
PubMed1994

[Analysis on various deduction patterns of Yunqi theory in the Seven Major Discourses in suwen (plain questions)].

It is pointed out that in the Seven Major Discourses, there are different patterns of deducing Yunqi theory. The design and method of deduction are then dealt with. In the light of the fact that there was physician in the staff of astronomical organization in the Eastern Han Dynasty as well as the cultural background as a whole, it is concluded that the KYunqi theory was proposed at the turn of middle and later period of Eastern Han Dynasty.

China↗
PubMed1994

Ambulatory blood pressure monitoring in normotensive children.

OBJECTIVE: To assess reference values of ambulatory blood pressure in normotensive children. SUBJECTS AND DESIGN: Twenty-four-hour non-invasive ambulatory blood pressure monitoring (ABPM) was carried out in 241 healthy normotensive children aged from 6 to 16 years (126 boys, mean +/- SD age 11.2 +/- 2.7 years; 115 girls, mean +/- SD age 10.9 +/- 2.9 years). The subjects were subdivided into three age-sex groups: 6-9, 10-12 and 13-16 years. SETTING: Primary care. MAIN OUTCOME MEASURES: ABPM was performed using an oscillometric device (SpaceLabs model 90207) and appropriate cuff size during a regular school day. Blood pressure was measured every 20 min from 0600 to 2400 h, and thereafter every 30 min. At each monitoring session the following parameters were calculated for both systolic (SBP) and diastolic blood pressure (DBP): means and centiles for 24-h, daytime (0800-2200 h) and night-time (2400-0600 h); circadian variability, estimated as the blood pressure fall between the day and the night periods and the day: night ratio; and load, as the percentage of measurements above the age- and sex-specific 95th centile (P95). RESULTS: The upper limits of 'normality' for the mean of 24-h SBP and DBP estimated as the P95 in each age subgroup were 121/71 and 119/71 mmHg, 123/78 and 120/74 mmHg, and 124/78 and 125/75 mmHg, for boys and girls, respectively. A progressive increase in SBP with age was observed in both sexes, in contrast, DBP was similar throughout the age range. A nocturnal blood pressure fall of approximately 11 mmHg was observed for both SBP and DBP in all subgroups. The day:night ratio was 1.12 and 1.22 for SBP and DBP, respectively. The upper limit of blood pressure load, estimated as the P95 in all children, was 39% for SBP and 26% for DBP. A significant positive correlation was observed between casual blood pressure and 24-h ambulatory blood pressure (SBP: r = 0.61, P < 0.0001; DBP: r = 0.31, P < 0.0001). In general, mean ambulatory blood pressure, during the 24-h or the daytime period, was higher than casual blood pressure for both SBP and DBP. CONCLUSION: ABPM is feasible in children, and the values obtained are useful as a departure point in establishing reference values.

Adolescent↗
PubMed1994

Ambulatory blood pressure and microalbuminuria in essential hypertension: role of circadian variability.

OBJECTIVE: To assess the relationship of subclinical urinary albumin excretion with ambulatory and circadian variability of blood pressure. DESIGN AND METHODS: Patients with essential hypertension (82 males and 59 females, mean +/- SD age 38.9 +/- 7.3 years) who had never been previously treated for hypertension were included in the study. Patients with nephropathy or diabetes mellitus, hyperglycemia > 120 mg/dl, glomerular filtration rate < 80 ml/min per 1.73 m2, urinary tract infection and positive dipstick for albumin or glucose were excluded. Twenty-four-hour ambulatory blood pressure monitoring on a regular working day using an oscillometric device was performed. Twenty-four-hour urinary albumin excretion was measured on two separate days using an immunonephelometric assay. RESULTS: Microalbuminuric patients (urinary albumin excretion 30-300 mg/24 h, n = 31) had significantly higher mean ambulatory systolic blood pressure (SBP) and diastolic blood pressure (DBP) than those with normoalbuminuria (urinary albumin excretion < 30 mg/24 h, n = 96) during the 24-h, daytime (0800-2200 h) and night (2400-0600 h) periods, whereas for office blood pressure only DBP was significantly higher. Urinary albumin excretion was positively correlated with the means of SBP and DBP. Multiple regression analysis similarly confirmed that DBP during daytime was positively and day:night ratio of DBP inversely associated with urinary albumin excretion independent of age, sex and other parameters of ambulatory blood pressure. CONCLUSIONS: In conclusion, the present study indicates that, in middle-aged essential hypertensive patients, the presence of microalbuminuria is a marker for the presence of higher values of blood pressure throughout a 24-h period.

Adult↗
PubMed1994

A north-south comparison of blood pressure and factors related to blood pressure in the People's Republic of China: a report from the PRC-USA Collaborative Study of Cardiovascular Epidemiology.

OBJECTIVES: To compare blood pressures in northern (Beijing) and southern (Guangzhou) Chinese population samples aged 35-54 years, males and females, urban and rural, and to assess the role of blood pressure-related traits in explaining north-south differences. DESIGN: Cross-sectional surveys were conducted in 1983-1984 of northern and southern populations employed in industry (urban) or farming (rural). METHODS: In the north samples were selected from the Capital Iron and Steel Complex (urban) and Shijingshan district (rural); in the south samples from the Guangzhou Shipyard (urban) and Panyu County (rural) were used. RESULTS: The number of subjects surveyed in north and south were 4706 and 4179, respectively: 1500 and 1052 urban males, and 717 and 914 rural males; and 1300 and 1061 urban females, and 1189 and 1152 rural females, respectively. Average systolic (SBP) and diastolic (DBP) blood pressures, were consistently higher in the north than in the south. SBP and DBP were significantly and independently related to age, body mass index, heart rate, use of antihypertensive drugs, serum triglycerides level, alcohol use (males only) and inversely to cigarette smoking. Northerners were older, taller, heavier and had higher body mass index and triglycerides level than southerners. With adjustment of SBP and DBP for blood pressure-related traits, north-south blood pressure differences decreased, but remained significant for urban males, rural males and rural females, with sizeable differences for rural samples in particular. CONCLUSIONS: North-south differences in blood pressure in these samples are accounted for only partly by north-south differences in the cited blood pressure-related traits. The role of other traits requires assessment.

Adult↗
PubMed1994

beta-Carotene supplementation results in an increased serum and colonic mucosal concentration of beta-carotene and a decrease in alpha-tocopherol concentration in patients with colonic neoplasia.

The aim of this study was to evaluate the colonic mucosal beta-carotene (BC) concentration following supplementation with BC and to determine if an increase in BC concentration influences vitamin E (alpha-tocopherol) status. The concentration of BC and alpha-tocopherol was assessed in serum and colonic tissue obtained from subjects with a history of colonic polyps or resected cancer (Dukes A, B1, or B2). Serum and mucosal biopsy samples were obtained prior to and following 3 months daily p.o. supplementation with 30 mg of BC or placebo. The concentration of BC was significantly increased in serum and colonic mucosa from both polyp and cancer subjects following supplementation as compared to presupplementation values and values from subjects receiving a placebo. The concentration of alpha-tocopherol in serum from cancer subjects was significantly decreased in samples obtained at the end of 3 months of BC supplementation as compared to placebo-matched controls. In BC-supplemented polyp subjects the tissue concentration of alpha-tocopherol was also significantly decreased relative to presupplementation values. The results indicate that BC supplementation does result in a significant accumulation of BC in the colonic mucosa but that the alpha-tocopherol concentration in both serum and colonic tissue may be compromised by an increased intake of BC. The mechanism for the decrease in alpha-tocopherol in conjunction with the increase in BC will require further study in order to develop strategies which will prevent vitamin E deficiency in BC-supplemented individuals.

Adult↗
PubMed1993

Determinants of incident non-insulin-dependent diabetes mellitus among blacks and whites in a national sample. The NHANES I Epidemiologic Follow-up Study.

The excess incidence of non-insulin-dependent diabetes mellitus noted among African Americans in the past two decades may be attributable to variations in the distribution of specific risk factors, or the impact of these risk factors may differ by ethnicity or sex. Over the 16 years (1971-1987) of the First National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-up Study, 880 incident cases of diabetes mellitus developed among 11,097 white and black participants who were between the ages of 25 and 70 years at baseline. There were substantial differences among the four race/sex groups with respect to age at baseline, as well as marked differences in the distribution of several major risk factors for diabetes, including obesity, subscapular and triceps skinfold thickness, blood pressure, income, activity, and educational level. The age-adjusted incidence of diabetes over the course of the study was 15.0% among black women, while it was 10.9% among black men. White women and men experienced similar, more moderate risks of 7.0% and 6.9%, respectively. The 100% excess risk among black women and the 50% excess among black men can in large measure explain the recent marked increase in diabetes rates in the black community. Furthermore, at nearly every level of obesity, blacks had a higher risk of diabetes than whites, suggesting that other factors contributed to risk. A significant interaction between race and body mass index (weight (kg)/height(m)2) was likewise demonstrated in multivariate analysis. Baseline age, race, body mass index, and ratio of subscapular skinfold to triceps skinfold were significantly related to incident diabetes, both overall and in separate models for men and women; in the entire cohort and in women alone, blood pressure, activity level, and education also contributed to risk. Other interactions were tested but were not found to be important. Despite sampling difficulties and inconsistencies in the data, the NHANES I Epidemiologic Follow-up Study provides evidence that the associations of anthropometric and sociodemographic variables with diabetes may vary among subgroups which have different mean levels and distributions of these risk factors.

Adult↗
PubMed1993

Sex differences in the impact of coexistent diabetes on survival in patients with coronary heart disease.

OBJECTIVE: To evaluate the sex difference in the impact of diabetes on survival in patients with coronary heart disease. RESEARCH DESIGN AND METHODS: Cohort study based on a sample from a hospital registry in Chicago, IL. A total of 974 consecutive patients (585 men and 389 women) with angiographically confirmed coronary artery disease were followed for 4.6 yr. RESULTS: At baseline, 160 men and 155 women had diabetes. The age-adjusted relative risk of death from all causes for patients with diabetes versus patients without diabetes was 0.93 (95% confidence interval 0.65-1.34) in men and 1.99 (95% CI 1.30-3.05) in women. For cardiac death, the corresponding relative risk was 1.00 (95% CI 0.64-1.56) and 1.96 (95% CI 1.19-3.24) in men and women, respectively. Baseline differences in age, hypertension, body mass index, number of diseased vessels, and ejection fraction did not fully explain the excess mortality risk in diabetic women. Excess risk was apparent in both cardiac and noncardiovascular categories. Among nondiabetic patients, the risk of death was significantly lower in women compared with men (multivariate-adjusted relative risk = 0.61, 95% CI 0.41-0.89). However, the mortality risk of diabetic women became similar to men as a whole (relative risk = 1.13, 95% CI 0.80-1.60). CONCLUSIONS: Diabetes confers a substantially higher risk of mortality in women than in men when it occurs in the presence of coronary heart disease.

Age Factors↗
PubMed1993

Hypertension, diabetes, and obesity in Barbados: findings from a recent population-based survey.

A stratified random sample of 464 persons aged 40 to 79 years, drawn from enumeration registers in the Bridgetown area of Barbados, participated in this survey. The prevalence of hypertension (defined as systolic blood pressure of at least 160 mm Hg, diastolic blood pressure of at least 95 mm Hg, or use of antihypertensive medication) was 47% and 43% for women and men, respectively. Diabetes was present in 17% of all subjects (18% of women and 15% of men). Of the 209 hypertensive subjects, 82% were aware of their blood pressure status. The proportion of previously diagnosed hypertensive subjects on medication was 72% for men and 68% for women. Fifty-three percent of men and 42% of women were overweight (body mass indices [weight in kilograms divided by height in meters squared] between 25 and 30). However, 30% of women and 10% of men were obese (body mass indices over 30), supporting the growing recognition of the marked gender disparity in obesity among persons of African origin in the Caribbean. Body mass index was positively associated with hypertension (OR = 1.33; 95% CI: 1.1-1.6). Obese persons experienced a 2.6 times greater risk of hypertension compared to those with body mass indices below 25. Similar statistically significant associations were observed between diabetes and body mass index: OR comparing body mass index over 30 with body mass index under 25 was 2.5 (95% CI: 1.3-5.1) for all subjects, 1.0 (0.3-4.1) for men only, and 5.2 (1.9-14) for women only. Preventing obesity in this population could reduce the incidence of hypertension and diabetes by approximately 30% and 33% among men and women, respectively.

Adult↗
PubMed1993

Risk/benefit ratio of perioperative OKT3 in cardiac transplantation.

This study shows that perioperative OKT3 provides no benefit in terms of the time of onset or frequency of rejection or patient survival. However, it does result in an increased incidence of infection, particularly CMV infection. Thus, the risk/benefit ratio of perioperative OKT3 does not appear favorable. However, a multicenter, randomized trial including a larger number of patients and longer patient follow-up will be required to definitively answer the question.

Azathioprine↗
PubMed1993

Delay between onset of chest pain and arrival to the coronary care unit among minority and disadvantaged patients.

Prehospital delay is an important cause of out-of-hospital coronary mortality. To determine the effects of decision time delay in a patient population comprised mainly of blacks and the underprivileged, 74 consecutive patients with acute chest pain necessitating admission to the coronary care unit in a large urban hospital were studied. Delay time from onset of chest pain to the decision to seek medical care was markedly prolonged in patients with myocardial infarction (n = 24; mean time: 11.3 +/- 18 hours) as well as in patients with chest pain who did not develop myocardial infarction (n = 50; mean time: 20.5 +/- 26 hours). In addition, transfer time from the emergency room to the coronary care unit was likewise unduly long (mean time: 4 +/- 3.8 and 4.1 +/- 6 hours for patients with and without myocardial infarction, respectively). This study documents a significant delay in the decision time among patients with low socioeconomic status, mostly inner-city blacks, and in the transfer time from emergency room to the critical care unit in a large public hospital. These findings must be taken into consideration when planning strategies to improve the health-care delivery system to blacks and the underprivileged and further lend support to the practice of initiating thrombolytic therapy in the emergency room.

Black or African American↗
PubMed1992

The prognostic role of left ventricular hypertrophy in patients with or without coronary artery disease.

OBJECTIVE: To examine the association between echocardiographically determined left ventricular hypertrophy and mortality in patients with and without coronary artery disease. DESIGN: Cohort study with a mean follow-up period of 4 years. SETTING: An inner-city public hospital in Chicago. PATIENTS: A cohort of 785 patients, most of whom were black and had hypertension. INTERVENTIONS: Coronary arteriography for presumed coronary artery disease and echocardiography. MAIN OUTCOME MEASURE: All-cause and cardiac mortality. RESULTS: Left ventricular hypertrophy, based on left ventricular mass corrected for body surface area, was present in 194 of 381 patients (51%) with coronary artery disease and in 162 of 404 patients (40%) without coronary artery disease. Patients with left ventricular hypertrophy had worse survival than those without hypertrophy in both the group with coronary artery disease and the group without coronary artery disease. After adjustment was made for age at baseline, sex, and hypertension, the relative risk for death from any cause in patients with hypertrophy compared with patients without hypertrophy was 2.14 (95% CI, 1.24 to 3.68) among those with coronary artery disease and 4.14 (CI, 1.77 to 9.71) among those without coronary artery disease. CONCLUSIONS: Echocardiographically determined left ventricular hypertrophy is an important prognostic marker in patients with or without coronary artery disease. The effect of reversing ventricular hypertrophy in patients with and without coronary disease deserves further study.

Adult↗
PubMed1992

Survival rates with coronary artery disease for black women compared with black men.

OBJECTIVE: To evaluate the influence of gender on the prognosis of coronary heart disease among black patients. DESIGN: Cohort study based on a consecutive sample from a hospital registry, with a mean follow-up of 4 years. SETTING: An inner-city public hospital in Chicago, Ill. PATIENTS: The study included 1719 consecutive black patients (780 men and 939 women) who had any one of the following events: cardiac catheterization for presumed coronary heart disease, hospitalization for acute myocardial infarction, or coronary artery bypass grafting. RESULTS: Hospital and operative mortality rates following acute myocardial infarction and coronary artery bypass grafting were similar between the two sexes. The relative risks for cardiac death in women vs men were 0.88 (95% confidence interval [CI], 0.60 to 1.28), 0.79 (95% CI, 0.53 to 1.17), and 0.79 (95% CI, 0.34 to 1.85) for coronary artery disease, acute myocardial infarction, and coronary artery bypass grafting, respectively, after adjusting for age, history of diabetes, hypertension, angina pectoris and myocardial infarction, number of diseased vessels, and ejection fraction. Compared with patients of the same sex with normal angiograms, relative risk estimates were 5.0, 10.1, and 6.3 for women and were 1.8, 4.0, and 2.0 for men in the same three groups of patients, respectively. CONCLUSIONS: Survival with coronary artery disease in black women is similar to that observed in black men, but relative to members of the same sex without the disease, the prognosis for women is considerably worse than for men.

Black or African American↗