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G S Tell

Publications and source records attributed to G S Tell.

At least 55 records · Page 3Linked to original sources
PubMed1993

Ten-year follow-up of the Oslo Youth Study Smoking Prevention Program.

BACKGROUND: The Oslo Youth Study was designed to demonstrate that health education in schools can result in lowered rates of smoking and alcohol consumption, improved eating patterns, and increased physical activity. The study was conducted from 1979 to 1981 in six schools in Oslo, Norway. This article presents the 10-year follow-up outcomes of the Oslo Youth Study Smoking Prevention Program. METHODS: In the fall of 1989, former Oslo Youth Study participants were contacted through the mail and asked to complete a short questionnaire containing questions regarding smoking behavior. A total of 796 subjects participated (participation rate of 74.0%). RESULTS: Overall, there were no significant effects of the Oslo Youth Study Smoking Prevention Program on the onset of experimental smoking (ever having smoked) or regular smoking (weekly smoking). Significant intervention effects were observed, however, among baseline nonsmoking males; intervention students reported 30% less weekly smoking (35% vs 50%) and 25% greater nonsmoking status (58% vs 44%) in 1989 than did males having attended the reference schools. No treatment effects were observed for females. CONCLUSIONS: The results suggest that the smoking prevention program might have contributed to reduced long-term onset of smoking among participating male subjects.

Adolescent↗
PubMed1993

Recruitment of adults 65 years and older as participants in the Cardiovascular Health Study.

Few large-scale epidemiologic studies have enrolled older adults; hence, little is known about the feasibility of recruiting this group for long-term population-based studies. In this article we present the recruitment experience of the Cardiovascular Health Study (CHS), a population-based, longitudinal study of cardiovascular diseases in adults 65 years and older. Participants were sampled from the Health Care Financing Administration's (HCFA) Medicare eligibility lists in four US communities. Letters were mailed to 11,955 sampled individuals. Persons recruited were required to complete an extensive home interview and then a 4-hour in-clinic examination. Excluded were persons who were expected to be able to complete the baseline examination and who were not expected to return for the 3-year follow-up. Some 3654 participants were recruited from those randomly selected from the Medicare sampling frame. In addition, 1547 other age-eligible persons living in the household with the sampled individuals also participated, yielding a total of 5201 participants. Of those who were contacted, 9.6% were ineligible and 34.9% refused participation. Among those eligible, 38.6% refused and 57.3% were enrolled (the remaining did not refuse but were not enrolled before the recruitment ended). Data from a subsample indicate that compared to those who were ineligible or who refused, enrolled participants were younger, more highly educated, more likely to be married, and less likely to report limitations in activity. Compared to those who were eligible but refused, enrolled participants were less likely to have high blood pressure and stroke and more likely to have quit smoking and to perceive their health status as very good or excellent.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

Relation of serum zinc and copper to lipids and lipoproteins: the Yi People Study.

The relations of serum zinc (Zn) and copper (Cu) to serum total cholesterol (TC), low-density-lipoprotein and high-density-lipoprotein cholesterol (LDL-C and HDL-C) and triglycerides were investigated in a population-based sample of 399 men in Southern China. Serum Cu was inversely related to HDL-C (r = -0.21), while Zn/Cu ratio showed a positive association (r = 0.19). These relationships remained significant after adjusting for age, body mass index (kg/m2), physical activity, tobacco smoking and dietary cholesterol, fat, and fiber. While no significant association was observed between serum Cu and serum TC in univariate analysis, a significant negative association was observed in multivariate analysis, after adjustment for the above mentioned independent variables. No significant association between serum Cu and LDL-C was found. These observations, as well as those reported in other studies reviewed herein, suggest that Cu is implicated in the metabolism of HDL-C, although the mechanism involved is not fully understood. No significant associations were found between serum Zn and the lipid variables.

Adolescent↗
PubMed1992

Orthostatic hypotension in older adults. The Cardiovascular Health Study. CHS Collaborative Research Group.

The purpose of the present study was to assess the prevalence of orthostatic hypotension and its associations with demographic characteristics, cardiovascular risk factors and symptomatology, prevalent cardiovascular disease, and selected clinical measurements in the Cardiovascular Health Study, a multicenter, observational, longitudinal study enrolling 5,201 men and women aged 65 years and older at initial examination. Blood pressure measurements were obtained with the subjects in a supine position and after they had been standing for 3 minutes. The prevalence of asymptomatic orthostatic hypotension, defined as 20 mm Hg or greater decrease in systolic or 10 mm Hg or greater decrease in diastolic blood pressure, was 16.2%. This prevalence increased to 18.2% when the definition also included those in whom the procedure was aborted due to dizziness upon standing. The prevalence was higher at successive ages. Orthostatic hypotension was associated significantly with difficulty walking (odds ratio, 1.23; 95% confidence interval, 1.02, 1.46), frequent falls (odds ratio, 1.52; confidence interval, 1.04, 2.22), and histories of myocardial infarction (odds ratio, 1.24; confidence interval, 1.02, 1.50) and transient ischemic attacks (odds ratio, 1.68; confidence interval, 1.12, 2.51). History of stroke, angina pectoris, and diabetes mellitus were not associated significantly with orthostatic hypotension. In addition, orthostatic hypotension was associated with isolated systolic hypertension (odds ratio, 1.35; confidence interval, 1.09, 1.68), major electrocardiographic abnormalities (odds ratio, 1.21; confidence interval, 1.03, 1.42), and the presence of carotid artery stenosis based on ultrasonography (odds ratio, 1.67; confidence interval, 1.23, 2.26). Orthostatic hypotension was negatively associated with weight. We conclude that orthostatic hypotension is common in the elderly and increases with advancing age. It is associated with cardiovascular disease, particularly those manifestations measured objectively, such as carotid stenosis. It is associated also with general neurological symptoms, but this link may not be causal. Differences in prevalence of and associations with orthostatic hypotension in the present study compared with others are largely attributed to differences in population characteristics and methodology.

Aged↗
PubMed1992

Effect of dietary electrolytes upon calcium excretion: the Yi People Study.

OBJECTIVE: To investigate the relations of dietary sodium, potassium, calcium and magnesium with urinary calcium excretion. DESIGN: Cross-sectional epidemiologic study of 417 Chinese men with a wide variation of electrolyte intakes. METHODS: Three consecutive 24-h dietary recall data and three 24-h urinary samples were obtained on the same days. Urinary analyses included calcium, sodium, potassium, magnesium and creatinine. A fasting blood sample was obtained on the first morning, and serum analyses included electrolytes, creatinine and urea nitrogen. Correlation and regression analyses were used to examine the relation between electrolyte intake and calcium excretion. RESULTS: Whilst urinary calcium was not related to dietary calcium, it was significantly correlated with dietary sodium and potassium. A linear relationship was seen between dietary sodium, potassium and urinary calcium. After adjustment for age, body mass index, serum creatinine, dietary calcium intake and other electrolytes, urinary calcium was positively related to dietary sodium and negatively related to dietary potassium. This relation was seen at different levels of dietary calcium intake. The relation between magnesium intake and calcium excretion was inconsistent. CONCLUSION: These results suggest that sodium and potassium intake influence urinary calcium excretion in normotensive men.

Adult↗
PubMed1991

Comparison of hospital and neighborhood controls in a study of coronary artery disease.

Case-control studies of risk factors for coronary artery disease (CAD) have almost invariably employed hospital controls, with minimal or no coronary artery stenosis. Although there is an important advantage in knowing the CAD status of controls, such groups are subject to bias related to hospitalization. To evaluate the generalizability of results obtained from studies using hospital controls, we compared risk factors in 342 hospital controls free of angiographic evidence for CAD, 168 neighborhood controls without symptoms of CAD, and 450 CAD patients. Coronary artery disease in cases and hospital controls was established arteriographically. No significant differences were found between the male control groups for total and low density lipoprotein (LDL) cholesterol, LDL apo-B, pack-years of smoking, body mass index, proportion with hypertension, diabetes and family history of coronary heart disease. Compared with neighborhood controls, male hospital controls had significantly lower high density lipoprotein (HDL) cholesterol, higher triglycerides and uric acid and scored higher on the Framingham Type A behavior pattern scale. Among women, the hospital control group had significantly lower LDL cholesterol and fewer pack-years of smoking, and a greater prevalence of hypertension than the neighborhood group. A greater proportion of both male and female hospital controls had left ventricular hypertrophy, and there were more current smokers among the neighborhood controls in both sexes. Age adjustment did not change these comparisons. While very few neighborhood controls were treated with beta-blockers, 32.7% of male and 41.4% of female hospital controls were so medicated. Control for beta-blocker use eliminated the difference in HDL cholesterol and triglycerides between the two male control groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Case-Control Studies↗
PubMed1991

Perceptions of follow-up care in women with breast cancer.

One hundred one patients with breast cancer, 48 localized and 53 metastatic, were questioned about their perceptions of follow-up examinations. Patients with metastatic disease preferred more frequent follow-up. Most indicated that they wanted their physicians to ask them about pain and nutritional status at each follow-up visit and were aware of the tests they had received. Only a third of the patients recognized the value of the history in detecting recurrence, and two-thirds felt that the physical examination was helpful. Laboratory tests and imaging procedures were rated higher than the history in detecting recurrence. Most patients were unaware of the implications of a normal procedure or test and perceived "normal" as meaning an absence of cancer cells in the organ evaluated. Knowledge of the value and limitations of testing was not related to educational level or disease stage. Patients need to be educated about the effectiveness of follow-up examination. Greater emphasis should be placed on the history and physical examination, and the limitations of more costly laboratory and imaging procedures should be explained carefully.

Adult↗
PubMed1991

Effect of migration on blood pressure: the Yi People Study.

The Yi People Study was conducted in Puge County, Sichuan Province, People's Republic of China. Four population groups were surveyed for risk factors for cardiovascular disease. Included were two groups of Yi farmers living either in a high mountainous area in extremely remote villages at or above 2,750 meters elevation, or in a mountainside area at about 1,800 meters elevation. A third study group consisted of Yi farmers who migrated to the county seat during the 1950s. Local residents of the county seat, the Han people, constituted the fourth group. Blood pressure rises very little with age after puberty in Yi farmers, but there was a trend of increasing blood pressure with age in Yi migrants and Han. Mean body mass index (kg/m2) and heart rate were higher in Yi migrants than in Yi farmers. For men, both systolic and diastolic blood pressure were greater among Yi migrants than among Yi farmers. These differences persisted after adjusting for age and body mass index. Among women, after adjusting for age, BMI, and altitude, only diastolic blood pressure was lower among Yi farmers than Yi migrants. Yi migrants and Han had similar blood pressures. In 1986, a sample of men participated in more detailed studies of diet, serum, and urine. The proportion of energy from fat ranged from less than 10% among high-mountain Yi farmers to almost 40% among Yi migrants and Han. Compared with Yi farmers, Yi migrants consumed more sodium and less potassium, calcium, and magnesium, had lower serum potassium, and a greater sodium/potassium ratio. Urinary excretion of sodium, calcium, and the sodium/potassium ratio were all greater in Yi migrants than in Yi farmers, while the reverse was seen for potassium. These data suggest that changes in life-style, including dietary changes, contribute importantly to the higher blood pressure among Yi migrants.

Adult↗
PubMed1991

Relation of electrolytes to blood pressure in men. The Yi people study.

The relations of sodium, potassium, calcium, and magnesium to blood pressure were investigated in four groups of men (119 high-mountain Yi farmers, 114 mountainside Yi farmers, 89 Yi migrants, and 97 Han people) with a wide range of electrolyte intake in Puge County, Sichuan Province, People's Republic of China. Electrolytes were measured in diet, serum, and urine. Sodium excretion was 73.9 mmol/24 hr in high-mountain Yi farmers, 117.9 mmol/24 hr in mountainside Yi farmers, 159.4 mmol/24 hr in Yi migrants, and 186.0 mmol/24 hr in the Han people. In ecological correlation analysis, dietary and urinary sodium were significantly and positively correlated with both systolic and diastolic pressure, whereas serum sodium showed no relation with blood pressure. In diet, serum, and urine, potassium was negatively related to systolic and diastolic pressure, whereas the sodium/potassium ratio showed a positive association. With regard to calcium, only urinary excretion was significantly and positively related to blood pressure. No relation was found between magnesium and blood pressure. Analyses at the individual level confirmed the results for sodium and potassium seen at the ecological level, but in addition, dietary calcium and magnesium were significantly and negatively correlated to both systolic and diastolic pressure, and urinary magnesium was inversely related to diastolic pressure. These relations persisted after controlling for age, body mass index (kg/m2), heart rate, alcohol, and total energy intake in multiple regression analysis performed separately for electrolytes in diet, serum, and urine. In multiple regression analysis, an increase in sodium intake of 100 mmol/day corresponded to an increase of 2.3 mm Hg systolic blood pressure and 1/8 mm Hg diastolic pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Cigarette smoking cessation and extracranial carotid atherosclerosis.

Using B-mode ultrasonography, cigarette smoking was found to be a strong, independent risk factor for extracranial carotid atherosclerosis in 1692 black and white men and women admitted for diagnostic evaluation of the carotid arteries. We found that the difference in mean plaque thickness was smaller between past smokers and nonsmokers than between current smokers and nonsmokers, suggesting that the rate of progression of carotid atherosclerosis may be slower in people who quit smoking compared with people who continue to smoke.

Adult↗
PubMed1989

Risk factors for site specific extracranial carotid artery plaque distribution as measured by B-mode ultrasound.

The effect of age, sex, diabetes, hypertension, pulse rate and cigarette smoking on extracranial carotid artery plaque thickness evaluated by B-mode ultrasonography was investigated in a cross-sectional study of 698 white men, 730 white women, 77 black men and 76 black women as part of a clinical ultrasound registry. Subjects were between 24 and 98 years of age, with a mean age of 63 years. Arterial locations evaluated were: proximal, mid and distal common carotid; the bifurcation; and the proximal and mid internal and external carotids. In a general linear multivariate analysis with plaque thickness at each site as the outcome variable, cigarette smoking and age were the two most consistent risk factors, and affected plaque thickness at all the investigated sites. Hypertension affected more sites than diabetes, men had more plaques than women, and except for the common carotid, whites had more plaques than blacks. Thus, risk factors were not uniformly associated with atherosclerosis at all sites of the extracranial carotid arteries.

Adult↗
PubMed1988

Physical fitness, physical activity, and cardiovascular disease risk factors in adolescents: the Oslo Youth Study.

Aerobic fitness, resting pulse rate, and self-reported physical activity were examined along with prevalence of cardiovascular disease risk factors in a population-based study of 413 boys and 372 girls, ages 10 to 14 years. Cardiovascular fitness (VO2 max) was predicted from heart rate measured during submaximal bicycle exercise. For both genders, fitness level was significantly and inversely related to body weight, body mass index [weight in kilos/(height in meters)2], triceps skinfold thickness, systolic and diastolic blood pressure, and pulse rate and positively related to high-density lipoprotein/total cholesterol ratio and physical activity. In addition, fitness level was positively related to high-density lipoprotein cholesterol and negatively related to triglycerides in females; it was also negatively related to height, total cholesterol, and hematocrit in males. Analyses of covariance, controlling for sexual maturity ratings, revealed that students in the lowest quartiles of VO2 max had significantly higher body mass index and triceps skinfold thickness than students in the higher quartiles. After adjustment for body mass index and sexual maturity ratings, blood pressure and pulse rate in both genders were significantly higher among students in the lower quartiles of VO2 max than among the groups who scored higher on the fitness test. Higher levels of VO2 max were also associated with a more favorable lipid profile in females. In gender-specific multiple regression analysis, triceps skinfold thickness was the strongest predictor of VO2 max, followed by pulse rate. Our study provides evidence that higher levels of fitness are associated with more favorable risk profiles in adolescents.

Adolescent↗
PubMed1988

Postural changes in blood pressure and pulse rate among black adolescents and white adolescents: the Minneapolis Children's Blood Pressure Study.

Because studies have suggested a possible relation between vascular responsiveness to postural changes and risk of subsequent myocardial infarction, the reactivity of blood pressure and pulse rate to change from supine to standing positions was examined in 158 black males, 144 black females, 342 white males, and 272 white females aged 14-16 years. The study was part of the Minneapolis Children's Blood Pressure Study and was conducted during October to December 1985. Two blood pressure readings and one pulse reading were taken after five minutes of supine rest, immediately upon standing, and five minutes after standing. After adjustment for body mass index, mean systolic blood pressure decreased, and fourth- and fifth-phase diastolic blood pressures and pulse rate increased from supine to standing positions in all race and sex groups. Black males had significantly larger changes in systolic pressure than did white males (-5.9 vs. -4.1 mmHg), and males had significantly larger changes in fourth- and fifth-phase diastolic pressures compared with females of the same race (fourth-phase diastolic pressure, 8.0 vs. 4.1 mmHg for blacks and 10.0 vs. 4.8 mmHg for whites). Fifth-phase diastolic pressure increased more than did fourth-phase diastolic pressure in all groups. No race or sex differences were seen for pulse changes. For all race-sex groups, decreases in systolic pressure were positively correlated with initial levels of supine systolic pressure, whereas increases in fourth- and fifth-phase diastolic pressures were negatively correlated with corresponding initial levels. Measurement of postural changes may provide a clinically simple and reproducible way of testing for abnormalities in blood pressure and may better discriminate those at high risk of hypertension and its cardiovascular complications than would the commonly used single-seated blood pressure measurement.

Adolescent↗
PubMed1988

Relation between blood lipids, lipoproteins, and cerebrovascular atherosclerosis. A review.

Although blood lipids and lipoproteins are strongly related to coronary atherosclerosis, their association with cerebrovascular atherosclerosis is less clear. A review of more than 20 publications in which a relation was sought between plasma lipid and lipoprotein concentrations and cerebrovascular atherosclerosis leads to the general conclusion that such a relation exists and that it is stronger in older than in younger individuals. A relation was found between blood lipids and/or lipoproteins and the extent and/or severity of cerebrovascular atherosclerosis in all but three of 26 reviewed studies. However, the specific nature of the relation is obscure because the various studies cannot easily be compared with one another. Interstudy variations in lipoprotein fraction analyzed, methodology for the analysis of lipids and lipoproteins, arterial segment examined, population sampled, control selection in case-control studies, statistical analytic approach taken, and methodology for the assessment of arterial disease preclude pooled analyses. There is a clear need for further evaluation of this relation using standardized and up-to-date methodologies both for analyses of lipids and lipoproteins and for assessment of cerebrovascular disease in symptom-free volunteers as well as in symptomatic patients.

Arteriosclerosis↗
PubMed1987

Can self-reported body weight be used to evaluate long-term follow-up of a weight-loss program?

The purpose of this study was to determine whether former participants in weight-control programs would provide valid weight data by self-report in telephone interviews. Participants were 39 women and 107 men (aged 28 to 63 years) who were in year 4 or 5 post-treatment. These represented 95% of participants who had completed all annual clinic visits. Self-reported body weights obtained by telephone interview were validated against weight measured directly in a university clinic. Overall, self-reported weight was 5.9 lb (2.7 kg) (standard deviation = 7.0 lb) (2.9%) lower than the measured weight. Using regression analysis, the strongest predictor of measured weight was reported weight, for both men and women. The bias in self-report of weight seen here is of about the same magnitude and direction as that seen in population studies. We conclude that the use of self-reported weight is not adequate for the assessment of long-term weight-loss maintenance unless the magnitude of discrepancy is adjusted for.

Adult↗