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O D Williams

Publications and source records attributed to O D Williams.

At least 19 recordsLinked to original sources
PubMed2002

Patterns of lung function in asymptomatic nonsmoking men and women in the People's Republic of China.

PURPOSE: To evaluate patterns of lung function in healthy, working Chinese men and women in different geographic areas of the People's Republic of China (PRC). METHODS: We conducted lung function tests on 2926 asymptomatic, never smoking Chinese men and women aged 35-56 years residing in or around Beijing and Guangzhou. Within each of these locations, separate urban and rural samples were recruited. RESULTS: Age and height adjusted lung function was greater in Beijing than in Guangzhou, and within each city for residents of rural vs. urban areas. Among women, estimated rates of lung aging were greater in Beijing than in Guangzhou, and in urban vs. rural areas. Both FEV(1) and FVC exhibited a curvilinear association with body mass index. CONCLUSIONS: Lung function data from this largely working cohort exhibited marked geographic and urban-rural differences in this never smoking, adult Chinese cohort. Such variation is not uncommon and may reflect differences in body size, diet, and environmental and occupational exposures across these different settings. Caution should be used in applying published reference equations to populations from different parts of the PRC.

Adult↗
PubMed2001

Asthma is associated with weight gain in females but not males, independent of physical activity.

We tested whether asthma diagnosis is associated with weight gain and physical activity in 4,547 18 to 30-yr-old African American and white men and women, followed prospectively for up to 10 yr. Baseline asthma was most frequent in African American men. Incident asthma was more frequent in women. Incident asthma was associated with highest and lowest baseline and change in body mass index (BMI), in a J-shaped curve, after adjustment for other factors. When stratified by sex, this association was seen only in females. Subjects on average decreased physical activity and gained weight over time, but there was no significant difference in asthma prevalence by physical activity at baseline or asthma incidence by change in physical activity. Cigarette smoking in females was significantly associated with asthma incidence, but serum cotinine level at baseline among nonsmokers (reflecting environmental tobacco smoke [ETS] exposure) was not significantly associated with asthma. We conclude that gain in BMI predisposes to new asthma diagnosis in female young adults, but decreased physical activity does not explain the association of weight gain with asthma.

Adolescent↗
PubMed2001

Improving quality improvement using achievable benchmarks for physician feedback: a randomized controlled trial.

CONTEXT: Performance feedback and benchmarking, common tools for health care improvement, are rarely studied in randomized trials. Achievable Benchmarks of Care (ABCs) are standards of excellence attained by top performers in a peer group and are easily and reproducibly calculated from existing performance data. OBJECTIVE: To evaluate the effectiveness of using achievable benchmarks to enhance typical physician performance feedback and improve care. DESIGN: Group-randomized controlled trial conducted in December 1996, with follow-up through 1998. SETTING AND PARTICIPANTS: Seventy community physicians and 2978 fee-for-service Medicare patients with diabetes mellitus who were part of the Ambulatory Care Quality Improvement Project in Alabama. INTERVENTION: Physicians were randomly assigned to receive a multimodal improvement intervention, including chart review and physician-specific feedback (comparison group; n = 35) or an identical intervention plus achievable benchmark feedback (experimental group; n = 35). MAIN OUTCOME MEASURE: Preintervention (1994-1995) to postintervention (1997-1998) changes in the proportion of patients receiving influenza vaccination; foot examination; and each of 3 blood tests measuring glucose control, cholesterol level, and triglyceride level, compared between the 2 groups. RESULTS: The proportion of patients who received influenza vaccine improved from 40% to 58% in the experimental group (P<.001) vs from 40% to 46% in the comparison group (P =.02). Odds ratios (ORs) for patients of achievable benchmark physicians vs comparison physicians who received appropriate care after the intervention, adjusted for preintervention care and nesting of patients within physicians, were 1.57 (95% confidence interval [CI], 1.26-1.96) for influenza vaccination, 1.33 (95% CI, 1.05-1.69) for foot examination, and 1.33 (95% CI, 1.04-1.69) for long-term glucose control measurement. For serum cholesterol and triglycerides, the achievable benchmark effect was statistically significant only after additional adjustment for physician characteristics (OR, 1.40 [95% CI, 1.08-1.82] and OR, 1.40 [95% CI, 1.09-1.79], respectively). CONCLUSION: Use of achievable benchmarks significantly enhances the effectiveness of physician performance feedback in the setting of a multimodal quality improvement intervention.

Aged↗
PubMed2001

Ten-year changes in smoking among young adults: are racial differences explained by socioeconomic factors in the CARDIA study?

OBJECTIVES: This study investigated whether socioeconomic factors explain racial/ethnic differences in regular smoking initiation and cessation. METHODS: Data were derived from the CARDIA study, a cohort of 5115 healthy adults aged 18 to 30 years at baseline (1985-1986) and recruited from the populations of 4 US cities. Respondents were followed over 10 years. RESULTS: Among 3950 respondents reexamined in 1995-1996, 20% of Whites and 33% of African Americans were smokers, as compared with 25% and 32%, respectively, in 1985-1986. On average, African Americans were of lower socioeconomic status. Ten-year regular smoking initiation rates for African American women, White women, African American men, and White men were 7.1%, 3.5%, 13.2%, and 5.1%, respectively, and the corresponding cessation rates were 25%, 35.1%, 19.2%, and 31.3%. After adjustment for socioeconomic factors, most 95% confidence intervals of the odds ratios for regular smoking initiation and cessation in African Americans vs Whites included 1. CONCLUSIONS: Less beneficial 10-year changes in smoking were observed in African Americans, but socioeconomic factors explained most of the racial disparity.

Adolescent↗
PubMed2000

Relationship of hospital teaching status with quality of care and mortality for Medicare patients with acute MI.

CONTEXT: Issues of cost and quality are gaining importance in the delivery of medical care, and whether quality of care is better in teaching vs nonteaching hospitals is an essential question in this current national debate. OBJECTIVE: To examine the association of hospital teaching status with quality of care and mortality for fee-for-service Medicare patients with acute myocardial infarction (AMI). DESIGN, SETTING, AND PATIENTS: Analysis of Cooperative Cardiovascular Project data for 114,411 Medicare patients from 4361 hospitals (22,354 patients from 439 major teaching hospitals, 22,493 patients from 455 minor teaching hospitals, and 69,564 patients from 3467 nonteaching hospitals) who had AMI between February 1994 and July 1995. MAIN OUTCOME MEASURES: Administration of reperfusion therapy on admission, aspirin during hospitalization, and beta-blockers and angiotensin-converting enzyme inhibitors at discharge for patients meeting strict inclusion criteria; mortality at 30, 60, and 90 days and 2 years after admission. RESULTS: Among major teaching, minor teaching, and nonteaching hospitals, respectively, administration rates for aspirin were 91.2%, 86.4%, and 81.4% (P<.001); for angiotensin-converting enzyme inhibitors, 63. 7%, 60.0%, and 58.0% (P<.001); for beta-blockers, 48.8%, 40.3%, and 36.4% (P<.001); and for reperfusion therapy, 55.5%, 58.9%, and 55.2% (P =.29). Differences in unadjusted 30-day, 60-day, 90-day, and 2-year mortality among hospitals were significant at P<.001 for all time periods, with a gradient of increasing mortality from major teaching to minor teaching to nonteaching hospitals. Mortality differences were attenuated by adjustment for patient characteristics and were almost eliminated by additional adjustment for receipt of therapy. CONCLUSIONS: In this study of elderly patients with AMI, admission to a teaching hospital was associated with better quality of care based on 3 of 4 quality indicators and lower mortality. JAMA. 2000;284:1256-1262

Hospital Mortality↗
PubMed2000

Weight gain continues in the 1990s: 10-year trends in weight and overweight from the CARDIA study. Coronary Artery Risk Development in Young Adults.

The prevalence of obesity increased in the United States through the 1980s. The authors examined 10-year aging and secular (time-related) trends in the Coronary Artery Risk Development in Young Adults (CARDIA) cohort for indications of whether these trends are continuing and for ages of peak weight gain in young adults. CARDIA is a population-based, prospective study of 5,115 African-American and White men and women aged 18-30 years at baseline. Body weight and overweight prevalence were measured at five time points from 1985-1986 to 1995-1996. Linear, mixed-model regression was used to partition weight gain into that due to secular trends and that due to aging. Prevalence of overweight (body mass index (BMI) > or = 25.0 kg/m2) increased markedly, and prevalence of severe obesity (BMI > or = 40.0 kg/m2) doubled in all race-sex groups. Each race-sex group experienced significant secular weight gains, ranging from 0.96 kg/year (95% confidence interval: 79, 1.13) in African-American women to 0.55 kg/year (95% confidence interval: 0.41, 0.69) in White women. Significant secular gains were present during each follow-up period. Each race-sex group also experienced significant weight increases related to aging during their early to midtwenties. Secular trends for weight gain are continuing in CARDIA, but the magnitude of weight gain differed among the four race-sex groups.

Adolescent↗
PubMed2000

Weight gain and its correlates in Poland between 1983 and 1993.

BACKGROUND: Weight gain and its unfavorable consequences on coronary heart disease (CHD) risk have been observed worldwide. Determinants of weight gain were studied in a Polish cohort of 1042 men and women age 35-64 at baseline. Participants were randomly selected from an urban population in Warsaw and a rural population in Tarnobrzeg Province surveyed by investigators in Krakow. The surveys, part of the Pol-MONICA project, were conducted in 1983-1984, 1987-1988, and 1992-1993. The purpose of this report is to gain insight into the dynamics of weight gain in this population that could be helpful in identifying high-risk groups for intervention, and to determine if economic changes that took place shortly after the second survey had any impact on weight gain. METHODS: Weight, height and demographic characteristics were measured at each visit according to Pol-MONICA standard protocol. Body mass index (BMI) was calculated as kg/m2. Years of schooling, 7-day alcohol history and smoking history were self-reported. RESULTS: Sixty percent of the cohort gained some weight, averaging 0.3-0.7kg/y. Weight gain was highest in younger rural women, in urban men and in rural women with low education. In multiple linear regression, low education was related to a 1.29 kg greater weight gain (P<0.01), ex-smoking status was related to a 2.54 kg greater weight gain (P<0.001), and younger age was related to a 1.14 kg greater weight gain (P<0.001). CONCLUSION: Our results indicate a need to target intervention programs at young low SES adults. Developing effective means of reaching these vulnerable groups is a critical research goal.

Adult↗
PubMed2000

Comparison of electrocardiographic findings between Northern and Southern Chinese population samples.

BACKGROUND: Cardiovascular disease is rare in China, but there are few data on the prevalence of electrocardiographic (ECG) abnormalities in Chinese populations. METHODS: The ECG surveys were carried out in four Chinese population samples, in a total of 9,666 adults aged 35-54 in Beijing and Guangzhou, China from 1981 to 1984. Twelve-lead resting ECG tracings were coded by the Minnesota Code. RESULTS: Prevalence per 1,000 of abnormal ECG ranged from 77.4 to 209.8, and was higher for men than women and higher for Guangzhou than Beijing. Prevalence per 1,000 of major abnormalities in Guangzhou was 29.8 for men and 78.4 for women, higher than the 18.4 and 29.6 for counterparts in Beijing. The ECG changes attributed in 'Western' populations to coronary heart disease (CHD), such as large Q waves (Minnesota Code 1-1, 1-2) and ST-T abnormalities, were similar between Beijing and Guangzhou men, but Guangzhou women had much higher prevalence of ST-T abnormalities than Beijing women. Other ECG abnormalities such as A-V block, left branch bundle block, and left ventricular hypertrophy were rare in people of both sites. CONCLUSIONS: Compared with similar data from the US, these Chinese populations had a relatively low prevalence of ECG abnormalities putatively related to CHD. This corresponds with the low incidence of CHD in the Chinese population. However, within the Chinese populations of this study, a high abnormality rate appeared in a population with low incidence of CHD and hypertension (Guangzhou women). Reasons why ECG abnormalities do not parallel prevalence levels of CHD and hypertension remain to be elucidated.

Adult↗
PubMed2000

Incidence and correlates of hypertension in the Atherosclerosis Risk in Communities (ARIC) study and the Monitoring Trends and Determinants of Cardiovascular Disease (POL-MONICA) project.

OBJECTIVE: The purpose of this research is to assess short-term blood pressure change and hypertension incidence, and identify correlates of incident hypertension in the USA and Poland. DESIGN AND METHODS: Population-based samples aged 45-64 years at enrollment from the Atherosclerosis Risk in Communities (ARIC) and the Pol-MONICA studies: including 3777 whites from Minneapolis, Minnesota, USA suburbs (urban), 3635 whites from Washington County, Maryland, USA (semi-rural) and 3109 blacks from Jackson, Mississippi, USA surveyed in 1987-1989 and 1990-1992; and 389 persons from Warsaw, Poland (urban) and 322 from Tarnobrzeg Province, Poland (semi-rural) surveyed in 1987-1988 and 1992-1993. RESULTS: Age-standardized systolic and diastolic blood pressures at both screens were 9-20 and 5-9 mmHg higher in the Polish samples than in US blacks, who had higher levels than US whites. Age-adjusted annual hypertension incidence in both Polish male cohorts (6-8%) was higher than that in US white men (4%) and approaching that of US black men (7%); rates were also higher in Polish female cohorts (8-9%) than in US black women (8%), but nearly twice those in US white women (4%). Factors independently related to hypertension incidence included age, family history, smoking, baseline blood pressures and body mass index, and increase in body mass index and alcohol consumption between screenings. After adjustment for these factors, annualized hypertension incidence was similar in US white and Polish men (2.3 and 2.7%) compared with US black men (3.4%), and in US white and Polish women (1.5 and 1.3%) compared with US black women (3.9%). CONCLUSIONS: Despite substantial differences in blood pressure levels and age-standardized hypertension incidence rates, the differences in incidence between Polish and US white men appear to be explained largely by differences in risk factors for hypertension.

Adult↗
PubMed2000

Changes in US health care access in the 90s: race and income differences from the CARDIA Study. Coronary Artery Risk Development in Young Adults.

OBJECTIVE: Health care financing is changing rapidly in the United States. We investigated whether and how health care access is changing concurrently with changes in financing, with special attention to a minority population. METHODS: We examined a longitudinal biracial (half African-American, half White) urban cohort of 3,565 individuals, aged 25-37 years old, in 1992-93 and again in 1995-96. We measured access by self-reported (1) health insurance status, (2) regular source of medical care, and (3) lack of care due to financial problems. RESULTS: In 1992-93, 30.3% of the cohort experienced at least one access barrier, with a decline to 26.8% in 1995-96 (P<.005). However, access improved more for Whites than for African Americans; and access improved for higher, but not for lower, income groups (7% improvement for high income, vs 2% deterioration for lower income, P<.01). In addition, there was an 11% to 19% absolute increase in individuals making co-payments for health care utilization across all race/sex groups, with African Americans having markedly higher proportions of cost-sharing. African-American, low income, and unemployed individuals reported more acute care, but fewer outpatient visits. Income and employment explained racial differences. CONCLUSION: While access has improved or stabilized for higher income groups, there is a widening gap according to income, accompanied by an acute care pattern for low income groups that may be both inadequate and cost inefficient.

Adolescent↗
PubMed1999

Comparison of outcomes research with clinical trials using preexisting data.

Outcomes research using analysis of preexisting data is a relatively new field with the potential to improve the quality and effectiveness of medical care, and may provide a useful complement to randomized studies. Motivated by the growth of this research in the cardiovascular literature, this review offers a framework to identify the core concepts of outcomes research from database analyses by comparing and contrasting it with the randomized clinical trial.

Bias↗
PubMed1999

Interpreting age, period and cohort effects in plasma lipids and serum insulin using repeated measures regression analysis: the CARDIA Study.

Observed changes in health-related behaviours and disease risk factors may arise from physiological or environmental changes, or from biases due to sampling or measurement errors. We illustrate problems in the interpretation of such changes with longitudinal data from the Coronary Artery Risk Development in Young Adults (CARDIA) study. Mean plasma cholesterol was 14 mg/dl higher in 27- than in 20-year-old black men cross-sectionally, but longitudinally it declined by 4 mg/dl during the 7 years. To sort out these contradictory assessments of the effect of age/passage of time, we estimated age and period effects under the assumptions that age effects are a smooth function of age independent of period, and that period effects are changes common to persons across all ages. Simple estimates the age effect, such as the cross-sectional age slopes, may be confounded by cohort effects, by interactions of time and age after baseline, or by the occurrence of non-linearities in response after baseline. We note examples of each potential type of bias. The data and background literature support the assumption that cohort effects do not seriously compromise interpretation for these variables in the CARDIA study. Strong secular decreases in plasma cholesterol, apparently due to population-wide dietary change, mask increases with ageing. Age increases in triglycerides are largely explained by increases in body fatness. For these data, we cautiously accept the cross-sectional age slope as an estimate of ageing and the age-matched time trend as an estimate of secular trend.

Adolescent↗
PubMed1999

Achievable benchmarks of care: the ABCs of benchmarking.

Benchmarking is generally considered to be an important tool for quality improvement. Traditional approaches to benchmarking have relied on subjective identification of 'leaders in the field'. We derive an objective, reproducible and attainable Achievable Benchmark of Care (ABC) by measuring and analysing performance on process-of-care indicators. Three characteristics of the ABC that we deem essential are: (1) benchmarks represent a measurable level of excellence; (2) benchmarks are demonstrably attainable; (3) benchmarks are derived from data in an objective, reproducible and predetermined fashion. From these characteristics it follows that (4) providers with high performance are selected to define a level of excellence in a predetermined fashion, but (5) providers with high performance on small numbers of cases do not influence unduly benchmark levels. We use the 'pared mean' to operationalize the ABC. Roughly, the pared mean summarizes the performance of top-ranked providers whereby at least 10% of the patient pool across all providers is included. Bayesian estimators for adjustment of performance of providers with small sample sizes are used to rank providers. Randomized controlled trials to assess the independent effect of the ABC in quality improvement projects are under way. We have developed a methodology objectively and reproducibly to derive a level of excellent, attainable performance, based on measured performance by a group of providers. The ABC can be applied to groups of providers in communities, to institutions and departments within them, or to individual practitioners.

Bayes Theorem↗
PubMed1999

Heart rate and subsequent blood pressure in young adults: the CARDIA study.

The objective of the present study was to examine the hypothesis that baseline heart rate (HR) predicts subsequent blood pressure (BP) independently of baseline BP. In the multicenter longitudinal Coronary Artery Risk Development in Young Adults study of black and white men and women initially aged 18 to 30 years, we studied 4762 participants who were not current users of antihypertensive drugs and had no history of heart problems at the baseline examination (1985-1986). In each race-sex subgroup, we estimated the effect of baseline HR on BP 2, 5, 7, and 10 years later by use of repeated measures regression analysis, adjusting for baseline BP, age, education, body fatness, physical fitness, fasting insulin, parental hypertension, cigarette smoking, alcohol consumption, oral contraceptive use, and change of body mass index from baseline. The association between baseline HR and subsequent systolic BP (SBP) was explained by multivariable adjustment. However, HR was an independent predictor of subsequent diastolic BP (DBP) regardless of initial BP and other confounders in white men, white women, and black men (0.7 mm Hg increase per 10 bpm). We incorporated the part of the association that was already present at baseline by not adjusting for baseline DBP: the mean increase in subsequent DBP was 1.3 mm Hg per 10 bpm in white men, white women, and black men. A high HR may be considered a risk factor for subsequent high DBP in young persons.

Adolescent↗
PubMed1998

Health care access and seven-year change in cigarette smoking. The CARDIA Study.

OBJECTIVES: To determine associations among health care access, cigarette smoking, and change in cigarette smoking status over 7 years. METHODS: A cohort of 4,086 healthy young adults was followed from 1985-1986 through 1992-1993. Participants were recruited from four urban sites balanced on gender, race (African Americans and whites), education (high school or less, and more than high school), and age (18-23 and 24-30). Outcome measures were smoking status at Year 7, as well as 7-year rates of smoking cessation and initiation. RESULTS: For each of three access barriers reported at Year 7 (lack of health insurance, lack of regular source of medical care, and expense), participants experiencing the barrier had a higher prevalence of smoking, quit smoking less frequently, and started smoking more frequently; e.g., only 15% of participants with health insurance lapses quit smoking over the 7-year period, compared with 26% of those with insurance (P < 0.001). Results were similar for each race/gender stratum, and persisted after adjustment for usual markers of socioeconomic status: education, income, employment, and marital status. CONCLUSIONS: Health care access was associated with lower prevalence of smoking and beneficial 7-year changes in smoking, independent of socioeconomic status. The possibility that this is a causal relationship has implications in the prevention of cardiovascular disease, cancer and multiple other smoking-related diseases, and deserves further exploration.

Adult↗
PubMed1998

Differences in cardiovascular disease risk factors in black and white young adults: comparisons among five communities of the CARDIA and the Bogalusa heart studies. Coronary Artery Risk Development In Young Adults.

PURPOSE: To examine community differences in cardiovascular disease (CVD) risk factors among black and white young adults by combining data from two large epidemiologic studies. METHODS: Data are from participants aged 20-31 years in the Coronary Artery Risk Development In Young Adults (CARDIA) study (1987-1988; N = 4129) and the Bogalusa Heart study (1988-1991; N = 1884), adjusting for data collection differences prior to analysis. CARDIA includes four urban sites: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California. Bogalusa is a semi-rural town in Southeastern Louisiana. CVD risk factors examined were smoking status, body habitus, and blood pressure. RESULTS: In Birmingham and Bogalusa, more white than black women were current smokers; no ethnic differences were observed among men. In Chicago, Minneapolis, and Oakland, more blacks were current smokers than were whites. For all sites, educational level was strongly inversely related to current smoking status; ethnic differences were more apparent among those with up to a high school education. Among white men and women, prevalence of obesity (body mass index > 31.1 kg/m2 in men and 32.3 kg/m2 in women) was greater in Birmingham and Bogalusa than in Chicago. Minneapolis, and Oakland. Mean systolic blood pressures were highest in Bogalusa, and the proportion of black men with elevated blood pressure (> or = 130/85 mmHg) was higher in Bogalusa and Birmingham. CONCLUSIONS: Community and ethnic differences in CVD risk factors were observed among young adults in two large epidemiologic studies. Further studies may enhance our understanding of the relationship of geographic differences in CVD risk to subsequent disease.

Adult↗
PubMed1998

Poland and U.S. collaborative study on cardiovascular epidemiology hypertension in the community: prevalence, awareness, treatment, and control of hypertension in the Pol-MONICA Project and the U.S. Atherosclerosis Risk in Communities Study.

PURPOSE: The objectives of this manuscript are to assess differences in blood pressure levels and in hypertension prevalence, awareness, treatment, and control for selected rural and urban areas in the U.S. and Poland, where ischemic heart disease mortality trends are different. METHODS: Included are white persons aged 45-64 selected in Minneapolis, MN suburbs [urban] and Washington County, MD [semi-rural] from the U.S. Atherosclerosis Risk in Communities Study (ARIC) surveyed in 1987-89, and in Warsaw [urban] and Tarnobrzeg Province [semi-rural] from Poland's Pol-MONICA Project surveyed in 1987-88. Sample sizes were: U.S.--3,696 men, 3,801 women; Poland--875 men, 960 women. RESULTS: Mean blood pressures were > 15% higher for Polish samples than for the U.S. (p < 0.01). In multivariable analysis, hypertension was significantly positively related to age and body mass index (BMI) in both U.S. and Polish samples (except age in Polish men), and to heart rate in Polish samples and U.S. rural women. Smoking was significantly negatively related to hypertension in urban Polish and rural U.S. men. Hypertension awareness, treatment, and control were better in U.S. than in Polish samples. In the U.S. > 80% of subjects with hypertension (systolic blood pressure (SBP) > or = 160 mmHg or diastolic blood pressure (DBP) > or = 95 mmHg or on treatment) were controlled whereas in Polish samples < or = 17% of hypertensive men and 16% of hypertensive women were controlled. When SBP > or = 140 mmHg or DBP > or = 90 mmHg or on treatment defined hypertension, control was about 55% in U.S. samples and about 2% in Polish samples. CONCLUSIONS: Hypertension prevalence is higher and blood pressure levels are less well controlled in Polish than in U.S. samples. These striking differences can be expected to contribute to opposing trends in coronary heart disease (CHD) mortality in the two countries. Hypertension control programs in the U.S. are almost certainly responsible for much of the observed differences. There is a clear need for similar programs in Poland.

Blood Pressure↗