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Biomedical subjects

B M Psaty

Publications and source records attributed to B M Psaty.

At least 163 records · Page 9Linked to original sources

Overtreatment and undertreatment of hypertension.

Results from a large number of randomized clinical trials document conclusively that treatment of elevated systolic and/or diastolic blood pressure markedly reduces the risk of cardiovascular complications such as stroke and acute myocardial infarction. Detection, treatment and control of hypertension have major public health implications. A review of the literature suggests the existence of both overtreatment (defined as improper or incorrect diagnosis of hypertension, overaggressive and potentially dangerous blood pressure lowering and the use of expensive antihypertensive drugs with unproven mortality/morbidity benefits) and undertreatment (defined as unrecognized, untreated and poorly controlled hypertension). These current major issues in medicine are discussed.

Antihypertensive Agents↗

Temporal patterns of antihypertensive medication use among elderly patients. The Cardiovascular Health Study.

OBJECTIVES: To estimate the incidence of newly treated hypertension and to describe the patterns of antihypertensive medication use among those aged 65 years and older. DESIGN: Medicare eligibility lists from four US communities (Forsyth County, North Carolina; Washington County, Maryland; Sacramento County, California; and Pittsburgh, Pa) were used to obtain a representative sample of 5201 community-dwelling elderly for the Cardiovascular Health Study, a prospective cohort study of risk factors for coronary heart disease and stroke. Participants were examined at baseline and again 1 year later. The two examinations included standardized questionnaires, blood pressure measurements, and the assessment of medication use by medication inventory. In this cohort analysis, we excluded 231 subjects (4.4%) who did not return for follow-up, 69 (1.3%) who had missing data for medications, and another 495 (9.5%) who were taking "antihypertensive" medications for an indication other than high blood pressure. INTERVENTIONS: None. RESULTS: Among the 4406 participants, 1613 used antihypertensive medications at both visits. Between the two visits, 144 started and 115 stopped antihypertensive therapy. Among nonusers at baseline, the annual incidence of newly treated hypertension was 5.2% in women and 5.6% in men. Due to the number of participants who stopped therapy, the overall prevalence of antihypertensive treatment increased only slightly, from 40.7% to 41.1% in women and from 37.1% to 38.2% in men, during 1 year of follow-up. After adjustment for age, systolic blood pressure, number of antihypertensive drugs, diabetes, and cardiovascular disease, the newly treated hypertensives were about half as likely as the previously treated hypertensives to receive diuretics (odds ratio [OR], 0.59; P = .008) or beta-blockers (OR, 0.52; P = .01); and they were about twice as likely to receive calcium channel blockers (OR, 1.88; P < .004) or angiotensin converting enzyme inhibitors (OR, 2.40; P < .001). A similar pattern of within-person changes over time was apparent among the continuous users. CONCLUSIONS: Between June 1990 and June 1991, physicians were increasingly prescribing angiotensin converting enzyme inhibitors and calcium channel blockers in place of diuretics and beta-blockers for the treatment of hypertension in elderly patients, especially for those just starting therapy.

Adrenergic beta-Antagonists↗

Cholesterol reduction and the risk for stroke in men. A meta-analysis of randomized, controlled trials.

OBJECTIVE: Reducing serum cholesterol lowers the risk for ischemic heart disease, but its effects on other vascular diseases are unknown. Published trials were reviewed to determine the effect of cholesterol-lowering interventions on fatal and nonfatal stroke. DESIGN: Meta-analysis of randomized, controlled trials. DATA IDENTIFICATION: A literature search of English-language studies examining the effect of modified diets or medications on cardiovascular end points from 1965 to 1992 using MEDLINE and a review of references of five quantitative overviews of cholesterol reduction and coronary disease. DATA ANALYSIS: Thirteen studies met three eligibility criteria: patients randomized to intervention or control; fatal or nonfatal stroke reported separately; and end points assessed without knowledge of treatment status. Heterogeneity among studies and overall effects of treatment on fatal and nonfatal stroke were estimated using the Mantel-Haenszel-Peto method to combine independent study results. The influence of various study designs and interventions was explored using subgroup comparisons. RESULTS: For fatal stroke, the overall odds ratio associated with cholesterol-lowering interventions in 13 trials was 1.32 (95% Cl, 0.94 to 1.86), and the odds ratio for the 10 single-intervention trials was 1.34 (Cl, 0.91 to 1.96). Among eight trials reporting nonfatal events, the summary odds ratio for nonfatal stroke for treated participants compared with controls was 0.88 (Cl, 0.70 to 1.11), and the odds ratio for total strokes was 0.98 (Cl, 0.80 to 1.19). Among three trials using clofibrate, treatment significantly increased the risk for fatal stroke (odds ratio, 2.64; Cl, 1.42 to 4.92) but not for nonfatal stroke (odds ratio, 0.87; Cl, 0.61 to 1.26). Regression analysis showed no statistical association between the magnitude of cholesterol reduction and the risk for fatal stroke. CONCLUSIONS: Lowering serum cholesterol through modified diets or medications does not reduce stroke mortality or morbidity in middle-aged men. Clofibrate appears to increase the risk for fatal strokes, but the mechanism for this effect is unknown.

Anticholesteremic Agents↗

A review of the association of estrogens and progestins with cardiovascular disease in postmenopausal women.

The purpose of this article was to review, with special attention to the hypothesized mechanisms of atherosclerosis and thrombosis, the literature on the association of estrogens and progestins with cardiovascular disease. The data sources included recent reviews and their citations as well as literature searches of Medline. For coronary heart disease, we relied on a recent meta-analysis; for the lipid effects of estrogens and progestins, we refer to recent reviews and studies; for stroke, we identified all cohort and case-control studies; and for the effects of hormones on coagulation factors, we identified all relevant studies. The lipid effects of estrogens in postmenopausal women probably prevent atherosclerosis, and we would expect long duration of use rather than current use to provide the greatest benefit. Few epidemiologic studies have, however, assessed duration of estrogen use. High doses of estrogens are likely to be thrombogenic during current use, and it is possible that even moderate doses may increase the risk of clotting among women who smoke or who have existing coronary atherosclerosis. Compared with the lipid effects of estrogens alone, the lipid effects of combined therapy with progestins may increase atherosclerosis. The effect of progestins on coagulation factors is largely unknown, and no epidemiologic study has assessed the risk of cardiovascular disease associated with the use of combined hormone therapy in postmenopausal women. Cardiovascular risk or benefit associated with the use of postmenopausal hormones may involve several competing mechanisms, including effects on prostaglandins and vascular tone as well as atherosclerosis and thrombosis.

Aged↗

Prevalence of cardiovascular diseases among older adults. The Cardiovascular Health Study.

The Cardiovascular Health Study is a population-based longitudinal study of 5,201 adults aged 65 years and older. Prevalences of myocardial infarction, angina pectoris, congestive heart failure, peripheral artery disease, stroke, and transient ischemic attack were ascertained between June 1989 and May 1990 in participants recruited from Forsyth County, North Carolina; Washington County, Maryland; Sacramento County, California; and Pittsburgh, Pennsylvania. A medical history was taken to obtain self-reports of prevalent disease. For all participants, use of nitrates was ascertained to document angina, electrocardiograms were used to document prevalent myocardial infarction, and ankle-arm blood pressure studies were used to document peripheral artery disease. Self-reports of disease that were not confirmed by examination findings were further investigated by examination of medical records. Reported disease that was confirmed by examination findings or by medical records was classified as "definite." Disease that was documented by examination, but not reported by the participant, was classified as "unreported." The prevalence rates of definite myocardial infarction and angina were 11% and 15%, respectively, among men aged 65-69 years, 18% and 17% among men aged 80-84 years, 4% and 8% among women aged 65-69 years, and 3% and 13% among women aged 80-84 years. Twenty-three percent of men and 38% of women with electrocardiographic evidence of myocardial infarction did not report it. These results suggest that prevalent disease estimates based only on self-report may underestimate the prevalence of cardiovascular diseases in older Americans.

Age Factors↗

Can measures of the grocery store environment be used to track community-level dietary changes?

BACKGROUND: This article examines whether an in-store unobtrusive survey of grocery store product displays can be used to track community-level dietary behavior. METHODS: The survey was conducted in 12 western communities two different times to measure two aspects of the grocery store environment: (a) the relative availability of low-fat and high-fiber products and (b) the amount of store-provided health-education information. Self-reported dietary intake of residents was obtained in the same 12 communities using a telephone survey. We compared the individual and store-level measures both cross-sectionally and over time. RESULTS: We found positive and statistically significant correlations between the availability of healthful products in stores and the reported healthfulness of individual diets in cross-sectional analyses, but correlations between changes over time in the two measures were weaker and not statistically significant. The variance of the grocery store measures was nonetheless sufficiently small that a grocery store survey of 15 stores in each of 8 communities (n = 120 surveys) had power comparable to that of a telephone survey of 200 individuals/community (n = 1,600) surveys, at a fraction of the cost. CONCLUSION: Although the results provide further validation of cross-sectional measures of the grocery store environment, additional efforts are required to establish the validity of the grocery store survey as a method of measuring dietary change.

Advertising↗

Do communities differ in health behaviors?

Communities differ in the prevalence of various health behaviors, but it is not known to what extent these differences are due to "different types" of people living in them. We used data from the evaluation of the Henry J Kaiser Family Foundation Community Health Promotion Grant Program to study individual-level and community-level variation in health behaviors for 15 communities. Our results show (1) there was significant variation among these communities in prevalences of smoking, consumption of alcohol and dietary fat, and use of seatbelts; (2) these differences persisted after control for demographic, health status, and other health behavioral characteristics of the people in the communities; (3) the community effect on a particular person's behavior, as represented by R2, was very small (less than 1%); and (4) the adjusted differences in prevalences among communities were potentially large (for example, a 7 percentage point difference in the probability of smoking). Unique features of communities may influence health behaviors. These findings affirm the potential importance of contextual effects on individual health behavior and thus support the theory that changing the community environment may offer effective ways to change individual health behavior.

Adolescent↗

School lunch: a comparison of the fat and cholesterol content with dietary guidelines.

OBJECTIVE: To compare the fat and cholesterol content of the foods offered and selected in an elementary school lunch program with current dietary guidelines. DESIGN: For 105 school days we recorded the food items selected by elementary school students in an entire school district (262,851 meals) who were given a choice between two entrees. The nutrient content of foods was assessed with a computerized nutrient data base supplemented by the food manufacturers' data. SETTING: Sixteen elementary schools in the Bellevue (Washington) School District. PARTICIPANTS: The number of students eating school lunch averaged 2500 per day, of whom 25% were from households with incomes less than 185% of poverty. INTERVENTION: None. MAIN OUTCOME MEASURES: We determined the nutritional content of the average meal selected; the proportion of days when one of the two offered entrees met fat and cholesterol guidelines; and the proportion of children selecting the entrees that met the guidelines. RESULTS: The average lunch selected had 35.9% of calories from total fat and 12.6% from saturated fat, exceeding the guidelines of 30% and 10%, respectively. Lunch contained an average of 57 mg cholesterol (106 mg/1000 kcal) and met guidelines. One of the two daily entree choices met guidelines for both total fat and saturated fat on 20% of days, and met both fat and cholesterol guidelines on 14% of days. When available, entrees meeting the fat guidelines were chosen by 37% of students, and entrees meeting both fat and cholesterol guidelines were chosen by 34% of students. CONCLUSIONS: In this school district the average lunch selected did not meet the current guidelines for dietary fat; when given the choice, more than one third of students selected the entrees that met these guidelines.

Child↗

Associations of postmenopausal estrogen use with cardiovascular disease and its risk factors in older women. The CHS Collaborative Research Group.

BACKGROUND: Postmenopausal estrogen replacement therapy has been associated with favorable levels of cardiovascular disease risk factors, but these associations and the relations between estrogen use and subclinical disease have not been examined in large samples of older women. METHODS AND RESULTS: Present and past estrogen use was ascertained in 2955 women > or = 65 years old in the Cardiovascular Health Study, a study of risk factors for coronary heart disease and stroke in the elderly. Present estrogen use was reported by 12% of these women and past use by an additional 26.5%. Estrogen use (past or present) was strongly associated with lower low-density lipoprotein cholesterol, fibrinogen, glucose, insulin, obesity, and age and higher high-density lipoprotein cholesterol and socioeconomic status (all P < .0001). Estrogen users also had lower levels of subclinical disease as measured by carotid intimal-medial thickness, carotid stenosis grade, ECG left ventricular mass, and Doppler mitral peak flow velocities (each P < .02). Relations were similar in younger and older women (65 to 74 versus > or = 75 years) and smokers and nonsmokers and were unchanged after women with poor medication compliance were excluded. After adjustment for other factors, estrogen use was associated with decreased carotid wall thickness, although this association was of borderline significance after further adjustment for lipids. CONCLUSIONS: Postmenopausal estrogen use in this sample of older women was associated with favorable cardiovascular disease risk factor profiles and with lower measures of subclinical disease. These findings suggest that postmenopausal estrogen use may be associated with lower risk of cardiovascular disease in women well into the eighth decade of life.

Aged↗

Activating communities for health promotion: a process evaluation method.

OBJECTIVES: To date, evaluations of community-based prevention programs have focused on assessing outcomes, not the process of organizing communities for health promotion. An approach was developed to analyze community organization efforts aimed at advancing community health objectives. These organizational processes are referred to as community activation. METHODS: Information was gathered from 762 informants through a key informant survey conducted in 28 western communities. The data collected included informant ratings of community activation and information about interorganizational activities analyzed through network analytic techniques. RESULTS: Activation levels, as measured by informant ratings, varied across communities. Program coordination, as measured by network analysis, occurred, on average, approximately 30% of the time. Higher income communities tended to be more activated than lower income communities. CONCLUSIONS: There is a widely recognized need for improved information about health-related community organization activities. It appears possible to gather such information through key informant surveys and to develop measures of community organization status that can be used in the evaluation of community health promotion programs.

Community Participation↗

An environmental intervention to reduce dietary fat in school lunches.

OBJECTIVE: To determine whether making a low-fat entree available as one of two choices in an elementary school lunch program would reduce the fat content of meals selected by children. DESIGN: In this before-after trial, students had a daily choice between two entrees, one of which was sometimes low-fat. For 93% of school days during 14 consecutive school months, daily entree choices were recorded for 619,976 student meals. The fat content of entrees was assessed with a computerized nutrient database supplemented by food manufacturer's data. SETTING: Sixteen elementary schools in the Bellevue (Washington) School District. PARTICIPANTS: The number of students eating school lunch averaged 2440 per day, of whom 25% were less than 185% of poverty. INTERVENTION: After a baseline period of 6 months, the intervention increased the number of days per month when one of the two entrees had 30% or fewer calories from fat. MAIN OUTCOME MEASURES: Data for the entire district were combined to estimate for each month the percent of students who selected low-fat entrees and the percent of calories from fat in the average meal selected by students. RESULTS: During the 6 months before the intervention, a low-fat entree was available on 23% of days; it was selected by 39% of students; and the average meal selected by students had 36% of calories from fat. By the end of the 8-month intervention, a low-fat option was available on 71% of days; it was selected by 29% of students; and the fat content of the average meal dropped from 36% to 30% of calories from fat (P = .02). CONCLUSIONS: In this school district, many students, given the choice, selected low-fat entrees. Recommendations for dietary fat were met simply by the environmental intervention of increasing the availability of low-fat foods.

Child↗

Isolated systolic hypertension and subclinical cardiovascular disease in the elderly. Initial findings from the Cardiovascular Health Study.

OBJECTIVE: To assess the association between isolated systolic hypertension (ISH) and subclinical disease in adults aged 65 years and above. DESIGN: Medicare eligibility lists were used to obtain a representative sample of 5201 community-dwelling elderly persons for the Cardiovascular Health Study, a National Heart, Lung, and Blood Institute--sponsored cohort study of risk factors for coronary heart disease and stroke. In this cross-sectional analysis of baseline data, we excluded 3012 participants who were receiving antihypertensive medications, had clinical cardiovascular disease, or had a diastolic blood pressure of at least 90 mm Hg. MAIN OUTCOME MEASURES: For electrocardiogram: myocardial infarction, left ventricular hypertrophy, and left ventricular mass as measures of myocardial damage and strain; for echocardiography: left ventricular mass, fractional shortening, and Doppler flow velocities as measures of cardiac systolic and diastolic function; and for carotid sonography: carotid arterial intima-media thickness as a measure of atherosclerosis. RESULTS: Among the 2189 men and women in this analysis, 195 (9%) had ISH (systolic blood pressure, greater than or equal to 160 mm Hg) and 596 (23%) had borderline ISH (systolic blood pressure, 140 to 159 mm Hg). Systolic blood pressure was associated with myocardial infarction by electrocardiogram (P = .02). Borderline and definite ISH were strongly associated with left ventricular mass (P less than .001). While there was little association with cardiac systolic function, borderline and definite ISH were associated with cardiac diastolic function (P less than .001). Isolated systolic hypertension was also strongly associated with increased intima-media thickness of the carotid artery (P less than .001). CONCLUSIONS: While cohort analyses of future repeated measures will provide a better assessment of risk, both borderline and definite ISH were strongly related to a variety of measures of subclinical disease in elderly men and women.

Aged↗

Assessing response bias in random-digit dialling surveys: the telephone-prefix method.

Knowledge of the characteristics of survey non-respondents is important to determine generalizability to the population of interest. In a recent random-digit dialling survey of health behaviours only 73 per cent of the households contacted provided any information about household composition, and only 74 per cent of those actually completed the extended interview, for an overall response rate of 54 per cent. To identify possible biases we grouped all attempted phone numbers by their prefix, and looked for the association between the response rate for that prefix and other summary variables known about the prefix. A simulation study showed that the method can identify non-response biases if certain assumptions are correct. The analysis suggested that our survey data under-represent older people and those with a college education. We found no significant biases in health behaviours, possibly because the basic assumptions did not hold. This method may assist in identification of non-response bias in other studies.

Adult↗

Major electrocardiographic abnormalities in persons aged 65 years and older (the Cardiovascular Health Study). Cardiovascular Health Study Collaborative Research Group.

Electrocardiographic abnormalities are often found in older patients, but their prevalence in free-living elderly populations is not well-defined. In addition, the clinical significance of many of these abnormalities is uncertain. The prevalence of major electrocardiographic abnormalities was determined in 5,150 adults aged greater than or equal to 65 years from the Cardiovascular Health Study--a study of risk factors for stroke and coronary heart disease in the elderly. Ventricular conduction defects, major Q/QS waves, left ventricular hypertrophy, isolated major ST-T-wave abnormalities, atrial fibrillation and first-degree atrioventricular block were collectively categorized as major electrocardiographic abnormalities. Prevalence of any major electrocardiographic abnormality was 29% in the entire cohort, 19% among 2,413 participants who reported no history of coronary artery disease or systemic hypertension, and 37% among 2,737 participants with a history of coronary artery disease or hypertension. Prevalence of major electrocardiographic abnormalities was higher in men than in women regardless of history, and tended to increase with age. Major Q/QS waves were found in 5.2%, and more than half were in those who did not report a previous myocardial infarction. Major electrocardiographic abnormalities are common in elderly men and women irrespective of the history of heart disease.

Age Factors↗

Sodium and blood pressure: the puzzling results of intrapopulation epidemiologic studies.

Most intrapopulation epidemiologic studies have been unable to find a significant association between sodium intake and blood pressure. The researchers have offered 2 opposing explanations: the hypothesis of the genetic susceptibility to sodium and the hypothesis of a weak association in general population. The evidence for and against each hypothesis is reviewed. The direction of future research is suggested.

Animals↗

Assessing the use of medications in the elderly: methods and initial experience in the Cardiovascular Health Study. The Cardiovascular Health Study Collaborative Research Group.

The Cardiovascular Health Study (CHS), a cohort study of risk factors for coronary heart disease and stroke, recruited 5201 community-dwelling adults aged 65 years or older. To assess the prevalence of medication use at baseline, we used the method of medication inventory and transcribed information about drug names and doses from prescription bottles. Using a specially-written computer program, persons without a knowledge of drug nomenclature coded 10,511 (89%) of the 11,846 medicines entered. We compared the results of the medication inventory and answers to questions on specific medications for reliability and validity. The use of beta-blockers and beta-agonists assessed by the method of medication inventory, but not by the method of directed recall, was associated with a significant effect on mean heart rate. Among 5197 participants with medication data, 76.1% were taking at least one medicine, and the mean number of drugs per person was 2.28. Among those with a reported history of high blood pressure, participants with cardiovascular disease (CVD) were more likely to be treated, and they were more likely to be taking beta-blockers and calcium-channel blockers than those without CVD. Daily aspirin use was also more common among those with CVD (30.5% of women and 43.2% of men) than among those without CVD (14.0% of women and 14.0% of men). The prevalence of post-menopausal estrogen use differed significantly among the four clinical centers (range = 5.5%-22.5% of women). We conclude that this method of assessing medications was easy to use and provided estimates of exposure to drugs that may affect risk of cardiovascular disease.

Aged↗

The distribution of coagulation factors VII and VIII and fibrinogen in adults over 65 years. Results from the Cardiovascular Health Study.

The Cardiovascular Health Study (CHS) was designed to examine cardiovascular disease and its risk factors in older adults. We report here the distributions of the coagulation factors fibrinogen, factor VII, and factor VIII in a population-based cohort of men and women 65 years or older. In other studies of middle-aged individuals, these factors were shown to be associated with cardiovascular risk. In the CHS cohort, all three factors were elevated, compared to levels reported in middle-aged individuals, and fibrinogen and factor VIII values were higher in each successive age group; factor VII values, in contrast, declined slightly with age in the CHS cohort. Compared to white subjects, blacks had higher values for fibrinogen and factor VIII and lower values for factor VII. While women had markedly higher values for factor VII and factor VIII than men at all ages in the CHS, mean fibrinogen values were not different between men and women.

Age Factors↗

Level of blood pressure and risk of myocardial infarction among treated hypertensive patients.

To examine the association between the level of treated blood pressure and the incidence of myocardial infarction, we conducted a population-based case-control study of 912 members of a health maintenance organization who were receiving standard clinical treatment for hypertension. We found a J-shaped relationship between the most recently measured diastolic blood pressure and the risk of myocardial infarction, the lowest risk occurring at 84 mm Hg. The relative risk of myocardial infarction at 60 mm Hg was 2.07 (95% confidence interval, 0.86 to 5.01), and at 100 mm Hg, 1.45 (95% confidence interval, 1.02 to 2.06). Treated systolic pressure bore a linear relationship to the risk of infarction. We conclude that the optimum target range for diastolic blood pressure in hypertensive patients may be 84 to 90 mm Hg. Levels outside this range may be associated with increased risk of myocardial infarction.

Adrenergic beta-Antagonists↗