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Multistage blood pressure screening rules are often used to select subjects for clinical trials. Multiple blood pressure readings are taken over successive visits, and the subject must meet eligibility criteria at each visit. In this paper, the authors present methods which depend on the distribution of the subject's underlying blood pressure values (the predictive value approach) or, alternatively, the subject's observed mean over all screening visits (the empirical predictive value approach) given the observed mean after one or more visits. The authors apply these methods to data from Phase I of the Trials of Hypertension Prevention, which attempts to identify subjects with mean diastolic blood pressures in the range 80-89 mmHg over three screening visits. The estimated efficiency of these rules is evaluated in terms of the number of clinic screening visits needed per eligible subject. Relative to reexamining all subjects at each visit (no screening), these approaches can reduce the number of visits required by 27%. This is in contrast to the standard rule in which a subject must have an observed mean diastolic blood pressure of 80-89 mmHg on each of three consecutive visits, which requires twice as many clinic visits per eligible subject as not screening. Thus, the approach presented is useful in identifying eligible subjects for clinical trials in an efficient manner.

• Data from a community-based study of 3811 persons aged 65 years and older were used to describe the characteristics of headache in the elderly. Subjects were asked whether they experienced headache in the past year, the frequency and severity of their headaches, and whether they experienced three symptoms of migraine: unilaterality, nausea or vomiting, an aura preceding the headache. Prevalence of headache in those aged more than 65 years declined with age in both men and women; women had a higher prevalence in each age group. The same was true for frequent, severe, and migrainous headache. We examined age- and sex-adjusted correlations of headache with several medical and social factors. Prevalence of any headache was strongly associated with joint pain, depression, bereavement, waking during the night, use of eyeglasses, symptoms of temporomandibular joint dysfunction, and self-assessment of health. Similar variables were associated with frequency, severity, and migrainous symptoms, and thus could not be distinguished among these various types.

During the early development of atriopulmonary anastomotic operations (Fontan-Kreutzer), a number of physiologic and anatomical limits were proposed by the Fontan group as selection criteria. Among 167 consecutive patients undergoing modified Fontan procedures from 1973 through 1985, 109 (65%) patients exceeded one or more of the original selection criteria in areas of age, anomalies of systemic or pulmonary venous connection, pulmonary artery distortion, and pulmonary artery pressure. Twenty-six patients had a mean pulmonary artery pressure greater than 15 mm Hg, with 16 operative survivors (62%). Nineteen patients had anomalies of systemic and/or pulmonary venous connection, and 16 survived (84%). There were 44 patients under the age of 4 years, and 26 survived (59%). Twenty-five patients were older than 15 years, and 23 (92%) survived the Fontan procedure. Pulmonary artery distortion, relating to prior palliative operations, was found in 34 patients. Seventeen of these 34 survived a modified Fontan procedure (50%). Twenty-six patients had a pulmonary arteriolar resistance more than 2 Wood units times square meter, and 14 survived (54%), whereas 81 of 93 with a pulmonary arteriolar resistance of less than 2 U X m2 survived (87%). Multivariate analysis showed that pulmonary arteriolar resistance and pulmonary artery distortion had a significant, negative impact on survival, but age and anomalies of systemic and/or pulmonary venous connection did not. Pulmonary artery pressure was not an independent predictor of outcome. The results show that the original criteria may be exceeded in the areas of age and anomalies of pulmonary or systemic venous connection. Pulmonary artery pressure alone should not contraindicate a Fontan procedure if pulmonary arteriolar resistance is low. Pulmonary artery distortion from a prior palliative operation and elevated pulmonary arteriolar resistance increase the risk of a Fontan procedure.

This prospective study directly examines, in a defined community population, the extent to which a wide array of characteristics predict utilization of an important long-term care (LTC) service--medical home care--over a two-year interval among the cohort of 3,706 people aged 65 or older. The overall age-sex adjusted rate of two-year incident home care use was 3.2 per cent. For both men and women, the rates among the aged 85 or older group were approximately 12 times the rates of those aged 65 to 74. The multivariate predictors of incident home care, adjusted for age and sex, were five: receiving help with at least one activity of daily living (ADL), being dependent in Rosow-Breslau functional health areas, being homebound, more errors in mental status items, and no involvement with social groups. The dominance of indicators of frailty in physical function and cognitive function are consistent with the predictors of another group of LTC clients, those who subsequently enter nursing homes. However, in the present study the ratios of medical home care use were similar for those living alone and for those living with others in the multivariate model, suggesting the possibility of differences between home care and institutional LTC clients.

A study of the variability of blood pressure was conducted among a total of 780 Massachusetts children, 335 children in East Boston and 445 children in Brookline, ages 8-18 years. All children had their blood pressure measured with a standard mercury sphygmomanometer in a school setting on four visits one week apart with three measurements per visit. In East Boston, repeat measurements were made for the same children for four consecutive years. A nested random effects model was used to estimate between- and within-visit variance components. For children aged 8-12 years, these were, respectively, 33.1, 12.0 in boys and 31.2, 11.1 in girls for systolic blood pressure and 57.7, 21.3 in boys and 56.6, 22.6 in girls for systolic muffling blood pressure (Korotkoff phase 4). For children aged 13-18 years of age, they were, respectively, 41.1, 11.8 in boys and 35.2, 12.2 in girls for blood pressure and 40.6, 15.5 in boys and 36.1, 11.4 in girls for diastolic blood pressure (Korotkoff phase 5). Within-person variability for systolic pressure was comparable to previously published data for 434 white adults ages 30-49 years not on antihypertensive medications; however, within-person variability for diastolic pressure was considerably higher in the children, accounting for over 75% of total variability among 8-12-year-old children, compared with 27% for adults. No meaningful effects of age, sex, or blood pressure level on variability of systolic pressure were found. However, age and level of blood pressure each had a large and independent inverse association with variability of diastolic pressure; variance components for younger children (ages 8-12 years) and children with low diastolic pressure (less than 60 mmHg) were approximately twice as large as for older children (ages 13-18 years) and children with diastolic pressure greater than or equal to 60 mmHg, respectively. Finally, predictive value estimates of blood pressure are provided for particular age-sex groups to enable one to efficiently identify children whose true mean level of blood pressure exceeds the 90th percentile for their age-sex group with minimum misclassification. Because of the substantial variability of diastolic pressure in young children, resulting in relatively low predictive value estimates, systolic pressure (either alone or in combination with diastolic pressure) may be more useful as the primary tool for screening children under age 13 years for high blood pressure.

A population survey was conducted in 1982-1983 among 3,812 persons aged 65 years and older residing in East Boston, Massachusetts, a geographically defined urban community. Three measurements of peak expiratory flow rate were obtained by using calibrated mini-Wright meters. Peak expiratory flow rate was strongly related to age, sex, smoking, and years smoked. After adjustment for these factors, low peak expiratory flow rate was associated with chronic respiratory symptoms (cough, wheeze, shortness of breath, exertional dyspnea, orthopnea, and paroxysmal nocturnal dyspnea; p less than 0.0001) and with certain cardiovascular variables (history of stroke, p = 0.0014; angina, p = 0.05; and high pulse rate, p = 0.004). No significant associations were found with history of myocardial infarction or systolic and diastolic blood pressures. Peak expiratory flow rate was positively related to education (p less than 0.0001) and income (p less than 0.0001). Peak expiratory flow rate also was strongly related (p less than 0.0001) to measures of functional ability and physical activity, self-assessment of health, and simple measures of cognitive function. The correlations of peak expiratory flow rate with pulmonary symptoms and other indices of chronic disease raise the possibility that peak expiratory flow rate will predict mortality in an elderly population.

Measurements of blood pressure were obtained on 2,673 women from East Boston, Massachusetts, an urban, working class neighborhood, in surveys conducted in both 1973 and 1976-1977. Of these, 927 women participated in a third survey in 1978. The women were 16 to 49 years of age in 1973, premenopausal throughout the study, and not on blood pressure medication. Regression analyses were performed of blood pressure change between the first and second as well as between the second and third surveys on initial blood pressure, age, weight, and patterns of oral contraceptive use. For systolic pressure the effect of starting oral contraceptive use was an increase of 4.1 mmHg (p less than 0.0001), while the effect of discontinuing use relative to continued use was a 4.4 mmHg decrease (p less than 0.0001). These changes were not affected by duration of use or time since last use among past users. For diastolic pressure the average effect of starting use between surveys was an insignificant 1.0 mmHg increase, but diastolic pressure level seemed to increase with duration of use (0.5 mmHg/year, p = 0.0009). The effect of discontinuing use relative to continued use was a drop of 2.7 mmHg in diastolic pressure (p = 0.0004), which was uninfluenced by time since last use.

Pulmonary function of approximately 200 school children in Steubenville, OH was measured before and immediately following air pollution alerts in the fall of 1978 and 1979. TSP concentrations exceeded the National Primary Ambient Air Quality 24 h standards in 1978. SO2 exceeded the standard in 1979. The children were then reexamined in three weekly visits following each alert. Estimated mean Forced Vital Capacity (FVC) was approximately 2% lower following each alert, although the lowest means were observed one to two weeks after the episodes. Forced Expired Volume in 0.75 sec (FEV0.75) did not change during the 1978 study, but was 4% lower immediately following the 1979 alert. The children were measured again in five weekly examinations in the spring and fall of 1980. Air pollution levels did not exceed the standards on either occasion. In the spring of 1980, estimated mean FVC and FEV0.75 showed a decline similar to that observed following the alerts in 1978 and 1979. In the fall of 1980, there were no s...

An increase in vascular responsiveness (increase in diastolic blood pressure) to phenylephrine (PE), noradrenaline (NA) or angiotensin (AII) was seen in pithed SHR when compared with normotensive controls (WKY). This increase in vasoconstrictor effect was not seen with the postsynaptic α2-adrenoceptor agonists BHT 933 or TL 99. In SHR and DOCA-salt hypertensive rats prazosin was significantly more potent as an antagonist of α1-receptor mediated vasoconstriction (PE, or the endogenous release of NA by electrical stimulation of the spinal cord), and was also more potent against NA administered by i.v. injection, compared with normotensive controls. The potency of yohimbine against the postsynaptic α2-receptor mediated pressor responses to TL 99 was not significantly different in SHR or normotensive rats. Although these results indicate an apparent shift in the ratio of postsynaptic α1/α2-receptor mediated effects in hypertension in vivo, these effects were not correlated with any changes in α-receptor densi...

In 1982 and 1983, brief, structured performance tests of selected areas of cognitive function were administered to 3,682 (82.1 per cent) of the residents aged 65 years and older of the geographically defined community of East Boston, Massachusetts, a center of the Established Populations for Epidemiologic Studies of the Elderly program. There was a strong inverse relation between age and performance on all four cognitive tests in analyses adjusted for sex only as well as in those adjusted for the effects of other variables. Similarly, fewer years of formal education, increasing level of disability on the modified Katz Activities of Daily Living Scale, and less prestigious occupations, as measured by the modified Duncan Socioeconomic Index, were each independently related to lower performance on all four tests.

We conducted a case-control study to evaluate the effectiveness of BCG vaccination in preventing childhood tuberculosis (TB) in Cali, Colombia. We ascertained 178 cases aged 0 to 14 years from the respiratory clinics with cough or fever for at least three weeks and a positive chest X-ray for TB, as well as 320 controls who were from the same households but had no symptoms and negative X-rays. Using matched set multiple logistic regression analysis, we found the age- and sex-adjusted relative risk (RR) of TB among vaccinees compared with non-vaccinees to be 0.84 with 95% confidence limits (CL) from 0.43 to 1.62. There was, however, a significantly lowered relative risk of TB with increasing time since vaccination (RR = 0.83 per year since time of vaccination with 95% CL from 0.74 to 0.94.)

Clinically diagnosed Alzheimer's disease and other dementing illnesses were assessed in a geographically defined US community. Of 3623 persons (80.8% of all community residents over 65 years of age) who had brief memory testing in their homes, a stratified sample of 467 persons underwent neurological, neuropsychological, and laboratory examination. Prevalence rates of Alzheimer's disease were calculated for the community population from the sample undergoing clinical evaluation. Of those over the age of 65 years, an estimated 10.3% (95% confidence limits, 8.1% and 12.5%) had probable Alzheimer's disease. This prevalence rate was strongly associated with age. Of those 65 to 74 years old, 3.0% (95% confidence limits, 0.8 and 5.2) had probable Alzheimer's disease, compared with 18.7% (95% confidence limits, 13.2 and 24.2) of those 75 to 84 years old and 47.2% (95% confidence limits, 37.0 and 63.2) of those over 85 years. Other dementing conditions were uncommon. Of community residents with moderate or severe cognitive impairment, 84.1% had clinically diagnosed Alzheimer's disease as the only probable diagnosis. These data suggest that clinically diagnosed Alzheimer's disease is a common condition and that its public health impact will continue to increase with increasing longevity of the population. (JAMA. 1989;262:2551-2556)

Publisher's version (útgefin grein), Aims: There is debate about the optimum algorithm for cardiovascular disease (CVD) risk estimation. We conducted head-to-head comparisons of four algorithms recommended by primary prevention guidelines, before and after 'recalibration', a method that adapts risk algorithms to take account of differences in the risk characteristics of the populations being studied. Methods and results: Using individual-participant data on 360 737 participants without CVD at baseline in 86 prospective studies from 22 countries, we compared the Framingham risk score (FRS), Systematic COronary Risk Evaluation (SCORE), pooled cohort equations (PCE), and Reynolds risk score (RRS). We calculated measures of risk discrimination and calibration, and modelled clinical implications of initiating statin therapy in people judged to be at 'high' 10 year CVD risk. Original risk algorithms were recalibrated using the risk factor profile and CVD incidence of target populations. The four algorithms had similar risk discrimination. Before recalibration, FRS, SCORE, and PCE over-predicted CVD risk on average by 10%, 52%, and 41%, respectively, whereas RRS under-predicted by 10%. Original versions of algorithms classified 29-39% of individuals aged ≥40 years as high risk. By contrast, recalibration reduced this proportion to 22-24% for every algorithm. We estimated that to prevent one CVD event, it would be necessary to initiate statin therapy in 44-51 such individuals using original algorithms, in contrast to 37-39 individuals with recalibrated algorithms. Conclusion: Before recalibration, the clinical performance of four widely used CVD risk algorithms varied substantially. By contrast, simple recalibration nearly equalized their performance and improved modelled targeting of preventive action to clinical need., The work of the co-ordinating centre was funded by the UK Medical Research Council (G0800270), British Heart Foundation (SP/09/ 002), British Heart Foundation Cambridge Cardiovascular Centre of Excellence, UK National Institute for Health Research Cambridge Biomedical Research Centre, European Research Council (268834), and European Commission Framework Programme 7 (HEALTH-F2-2012-279233). The Emerging Risk Factor Collaboration’s website https://www.phpc.cam.ac.uk/ceu/erfc/list-of-studies/ has compiled a list provided by investigators of some of the funders of the component studies in this analysis. I.W. was supported by the Medical Research Council Unit Programme MC_UU_12023/21. M.K. is supported by the Netherlands Organization for Scientific Research (NWO) Veni grant (Veni, 91616079). J.P. is supported by Erasmus Mundus Western Balkans (ERAWEB), a project funded by the European Commission.