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Biomedical subjects

D Sparrow

Publications and source records attributed to D Sparrow.

At least 127 records · Page 7Linked to original sources
PubMed1982

Factors in predicting blood pressure change.

A total of 1166 male participants (ages 23--80 years) of the Normative Aging Study who had baseline blood pressure less than 140/90 mm Hg were followed prospectively for 10 years. Blood pressures were taken at 5- and 10-year follow-up examinations. Multiple linear regression analysis indicated that baseline levels of systolic pressure, hematocrit, subscapular skinfold thickness and age were significant predictors of systolic pressure change during the follow-up period. Baseline levels of diastolic pressure, hematocrit, and body mass index were significant predictors of diastolic pressure change. Multiple logistic regression analysis revealed that only baseline blood pressure and hematocrit were significant predictors of subsequent blood pressure elevation to more than 159 mm Hg systolic or 94 mm Hg diastolic. Although the mechanisms by which hematocrit and body build affect blood pressure are unknown, these results suggest that identifying hypertension-prone subjects and delaying or preventing hypertension may be possible.

Adult↗
PubMed1982

Fire fighting and coronary heart disease.

Some studies suggest that fire fighters are at a higher risk of developing coronary heart disease than are males in the general population. We followed 1646 men for 10 years to determine the incidence of coronary heart disease. Subjects were participants of the Normative Aging Study, a longitudinal study of aging. Comparison of fire fighters (n = 171) and non-fire fighters (n = 1475) showed no significant difference in the incidence rates of coronary heart disease. Comparison of the groups regarding baseline risk factors revealed no material difference. These data suggest that fire fighters do not have an excess risk of coronary heart disease.

Adult↗
PubMed1982

The effect of occupational exposure on pulmonary function: a longitudinal evaluation of fire fighters and nonfire fighters.

To examine the chronic effect of fire fighting on pulmonary function, we undertook a longitudinal analysis of 168 fire fighters and 1,474 nonfire fighters enrolled in a study of normal aging. Spirometric measurements (FVC and FEV1) were obtained on all subjects over a 5-yr intake period (1963 to 1968) and these subjects were reexamined 5 yr later (1968 to 1973). Questionnaire information about smoking habits, respiratory symptoms, and illness was also obtained. Fire fighters had a greater loss of pulmonary function (FVC and FEV1) than nonfire fighters (p = 0.007 and p = 0.054). This occupational effect could not be explained by differences in age, height, smoking status, or initial level of pulmonary function between the two occupational groups. Although respiratory symptoms were greater among current cigarette smokers, they were not significantly different between either occupational group. However, fire fighters generally reported more symptoms when smoking was controlled for. These results confirm earlier reports of a chronic effect of fire fighting on pulmonary function and suggest an association of this occupational with increased respiratory symptoms and disease independent of cigarette smoke.

Adult↗
PubMed1982

The relationship of pulmonary function to copper concentrations in drinking water.

Copper has been shown to be an important cofactor for certain enzymatic reactions. Specifically, cross-linking of elastin is inhibited by copper deficiency. In animal models, this inhibition leads to weakened connective tissue and pathologic changes in the lungs consistent with emphysema. To explore the potential relationship of copper exposure to level of pulmonary function in humans, we examined copper concentrations in tap water in the homes of 297 adult male subjects involved in the Normative Aging Study. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were obtained by standard techniques. The relationship of tap water copper concentration to pulmonary function was explored using multiple regression analysis, controlling for other potential confounding variables (age, height, smoking status, and educational attainment). Separate regressions were performed for each of 3 smoking status groups: never, former, and current. Among never smokers, tap water copper was significantly and positively related to levels of both FVC (p = 0.014) and FEV1 (p = 0.027). No significant trend was found among former or current smokers. These data suggest that copper intake may be an important determinant of level of pulmonary function and deserves further investigation.

Adult↗
PubMed1982

Age-related failure of volume-pressure-mediated vasopressin release.

Osmoreceptor sensitivity, as estimated by the plasma vasopressin (AVP) response to hypertonic saline infusion, increases with age. We studied volume-pressure sensitivity, as estimated by the plasma AVP response to orthostasis, in healthy young (19-31 yr old; n = 12) and old (62-80 yr old; n = 15) subjects. After remaining recumbent overnight (minimum of 8 h), subjects stood quietly for 8 min. Cardiovascular changes on standing were not influenced by age. The peak plasma AVP response was greater in the young than in the old (P = 0.02, by rank sum test). When categorized as responders (peak AVP response, greater than or equal to 3 pg/ml) or nonresponders (peak response, less than 3 pg/ml), the young group included 11 responders and 1 nonresponder, while the old group included 8 responders and 7 nonresponders (P = 0.03, by Fisher exact test). There was no difference in the marked increase in plasma norepinephrine on standing between old responders (n = 6) and old nonresponders (n = 4). These studies indicate that failure to release AVP in response to orthostasis is more common in the elderly than in the young. The intact norepinephrine response to orthostatis in the elderly, regardless of the AVP response, suggests that the age-related defect is distal to the vasomotor center in the afferent limb of the baroreceptor reflex arc. Insensitivity to the volume and pressure changes accompanying hypertonic saline infusion may contribute to the previously noted augmented AVP response of the elderly to hyperosmolality.

Adult↗
PubMed1981

Effect of aging on the electrocardiogram.

Previous cross-sectional population studies have shown age differences in electrocardiographic wave patterns, including lower wave amplitudes and a leftward shift of the frontal plane axis in older people. However, cross-sectional results may be due to cohort differences and the data imply only that these changes actually occur in persons as they age. In order to examine electrocardiographic changes with aging in the same persons, serial recordings, obtained 10 years apart, were taken in 440 healthy male participants of the Normative Aging Study, who were 23 to 66 years old on their first examination. At examination 1, R and S wave amplitudes were smaller and frontal plane axis measurements were shifted to the left in older men. Longitudinal changes in these same variables were consistent with the cross-sectional results. In addition, the P-R and Q-T interval durations were longer, the QRS duration was shorter and the T wave amplitude was smaller at the second examination. The longitudinal rate of change of S wave amplitude varied among age groups, decreasing more in younger men. Thus, some previously described cross-sectional age differences truly represent longitudinal age trends in electrocardiographic patterns.

Adult↗
PubMed1981

Cross-sectional and longitudinal changes in the erythrocyte sedimentation rate in men.

The erythrocyte sedimentation rate (ESR) was determined on 1480 initially "healthy" male participants of the Normative Aging study on three successive examinations over a ten year period. Cross-sectional analysis revealed a significant correlation between age and ESR (r = 0.20, p less than 0.001) with generally higher ESR values in older individuals. Longitudinal analysis showed significant increases in ESR among "healthy" subjects who continued to pass our criteria for good health over a ten year period (p less than 0.001) and among "excluded" subjects who did not pass these criteria (p less than 0.001). Longistic regression analysis indicated that the ESR was significantly related to risk of death among subjects less than 45 years of age (p = 0.04) but not among subjects 45 + years (p = 0.39).

Adult↗
PubMed1981

Longitudinal effect of age and smoking cessation on pulmonary function.

Although it is well known that pulmonary function declines with age and that this decline is accelerated by cigarette smoking, it is not as clear what effect smoking cessation has on pulmonary function. The Normative Aging Study, a longitudinal aging study of 2,280 men, has assessed this question. Longitudinal data on smoking and pulmonary function were available on 850 healthy men. Of 452 who smoked at entry to the study, 98 quit during a 5-yr period. There were no significant differences between current and ex-smokers in FVC (p = 0.12) and FEV1 (p = 0.66) at entry into the study. However, significant differences were observed during the 5-yr period in FVC and FEV1 decline between current, former, and never smokers, after adjusting for age and initial pulmonary function. The decrease in FVC for men who quit smoking was significantly less than that for current smokers (p = 0.02). Similarly, FEV1 for former smokers decreased significantly less than for current smokers (p less than 0.001). When multiple regression was performed among former smokers, no significant effects of years since quitting on rate of decrease in FVC and FEV1 were seen. This study suggested a definite and rapid beneficial effect of smoking cessation.

Adult↗
PubMed1980

Enhanced plasma norepinephrine response to upright posture and oral glucose administration in elderly human subjects.

Plasma norepinephrine (NE) levels in response to upright posture and to oral glucose ingestion were measured in healthy young and old (greater than 65 yr of age) subjects. Peak plasma NE concentrations with standing were higher in the elderly (1334 +/- 146 pg/ml versus 855 +/- 46; p less than 0.05) and plasma NE remained elevated in the elderly compared with the young subjects even after 15 min of recumbent resting. Following oral glucose plasma NE rose higher in the elderly (79% compared with 32% in the young) and peaked later (120 min after ingestion compared with 60 min in the young). Cardiovascular changes with upright posture and with oral glucose were similar in young and old. Alterations in disappearance of NE from the circulation could not account for the greater elevations in plasma NE concentration in the elderly either, since the rates of fall in circulating NE levels following termination of an NE infusion were the same in both groups. The metabolic clearance rate of NE was unchanged. Thus, the plasma NE responses to stimulation by standing and by oral glucose ingestion are enhanced in elderly subjects.

Adolescent↗
PubMed1980

The influence of age on peripheral lymphocyte count in men: a cross-sectional and longitudinal study.

The peripheral lymphocyte count was determined on 436 carefully screened healthy male participants of the Normative Aging Study on three successive determinations over a ten year period. Cross-sectional analysis revealed no significant differences in absolute lymphocyte count between the age groups 23 to 44, 45 to 54, and 55+ years. Longitudinal analysis also showed no significant change in absolute lymphocyte count over the study period. These results indicate that absolute lymphocyte count in healthy men does not change with age.

Adult↗
PubMed1980

The influence of age, alcohol consumption, and body build on gonadal function in men.

Basal plasma levels of testosterone, dihydrotestosterone, estradiol, and gonadotropins and testosterone-binding capacity (percent radioactive testosterone bound to protein) were measured in health carefully screened young (31-44 yr old; n = 44) and older (64-88 yr old; n = 42) male participants in the Normative Aging Study of the V.A. There was no statistically significant effect of age on testosterone [younger group, 4.16 +/- 0.27 (SEM) ng/ml; older group, 4.62 +/- 0.32 (SEM) ng/ml] or the free testosterone index [younger group, 2.05 +/- 0.14 (SEM) ng/ml; older group, 1.76 +/- 0.11 (SEM) ng/ml]. The testosterone-binding capacity was higher in the older group (younger group, 50.10 +/- 1.18% (SEM); older group, 60.10 +/- 1.18% (SEM); P less than 0.001). Of the two products of testosterone metabolism studied, estradiol did not change with age, while dihydrotestosterone was lower [young group, 0.25 +/- 0.02 (SEM) ng/ml; older group, 0.20 +/- 0.01 (SEM) ng/ml; P = 0.03] in the older group. FSH levels were increased among the older men [older group, 92.9 +/- 6.0 (SEM) ng/ml; younger group, 61.1 +/- 5.0 (SEM) ng/ml; P less than 0.001]. LH levels were not significantly influenced by age. There was no effect of level of chronic stable alcohol intake on gonadal function, as estimated by testosterone levels and the free testosterone index. Analysis of the relationship between body build and hormone levels indicated that estradiol levels were highest in gynandromorphic men and lowest in mesomorphic men.

Adult↗
PubMedDate not supplied

Cigarette smoking, aging, and decline in pulmonary function: A longitudinal study.

Three serial spirometric determinations of forced vital capacity (FVC) and forced expiratory volume in 1 sec (FEV1.0) were performed during a 10-yr period for 268 adult male cigarette smokers, 181 quitters, and 254 who had never smoked. Smokers were further divided into high- and low-tar consumption groups. Spirometric data were analyzed by repeated measures analyses of variance using time (aging) and smoking status as independent variables and age as a covariate. Results indicated that FVC and FEV1.0 were relatd to smoking status. For all age groups, nonsmokers performed best on spirometry, while current smokers performed worst. The decline in FEV1.0 over time was greatest in current smokers, especially the high-tar group. Loss of FVC over time was not influenced by smoking status.

Adult↗
PubMedDate not supplied

The influence of cigarette smoking and age on bone loss in men.

Hand X-rays were examined among 341 healthy male participants (age 40-80 yr) of the Normative Aging Study who had two successive X-rays 3 to 5 yr apart. Bone density was estimated at midshaft of the second metacarpal as percent cortical area. As expected, cross-sectional analysis revealed a decrease in percent cortical area with age. Current smokers tended to have slightly lower percent cortical areas than "never" smokers. When participants were followed longitudinally over a 3 to 5 year period, a trend toward greater bone loss with increasing age was generally observed in both smoking status groups, although smokers' rate of loss after age 55 yr deviated slightly from this pattern. Current smokers under age 55 yr consistently showed greater bone loss than never smokers.

Adult↗
PubMedDate not supplied

Smoking status and the electrocardiogram: a cross-sectional and longitudinal study.

Previous cross-sectional studies have shown age trends in electrocardiographic wave patterns, including leftward shift in frontal plane axis and decreases in R, S, and T wave amplitudes with age. The effects of smoking on electrocardiographic measurements have also been examined. Findings of several studies vary and include possible smoking-induced changes in T wave amplitude and frontal plane axis measurements. To examine both cross-sectionally and longitudinally the effects of cigarette smoking on electrocardiographic measurements, serial recordings obtained 5 yr apart were taken from 702 healthy male participants of the Normative Aging Study, who were 23-74 yr of age at their first examination. These men were classified as current smokers (at both baseline and follow-up examinations, N = 291), former smokers (men who stopped smoking prior to the baseline examination, N = 203), or never smokers (at any time, N = 208). At baseline, P-R interval duration was shorter in current smokers than in former or never smokers. Longitudinal results indicated that R, S, and T wave amplitudes decreased at greater rates in smokers than in nonsmokers. These findings suggest that changes in the electrocardiogram attributed to aging may be modified by smoking.

Adult↗
PubMedDate not supplied

Gender differences in psychophysiological responses to speech stress among older social phobics:: congruence and incongruence between self-evaluative and cardiovascular reactions.

OBJECTIVE: Evidence suggests increased cardiovascular risk and autonomic impairment among individuals with chronic anxiety. Little attention, however, has been paid to the anxiety disorder of social phobia despite its high prevalence. Additionally, gender- and age-related cardiovascular profiles have not been examined in relation to social phobia. This study investigated cardiovascular responses to a socially threatening situation among older men and women with social phobia and control subjects. METHODS: Thirty subjects with social phobia and 30 control subjects (mean age = 65 years) were assessed during baseline, paced breathing, speech preparation, and speech presentation. Electrocardiographic variables, blood pressure, respiration, and emotional state (self-reported) were monitored. Hemodynamic variables included heart rate, blood pressure, cardiac output, and systemic vascular resistance; autonomic measures were respiratory sinus arrhythmia and baroreflex sensitivity, both markers of cardiac vagal control, and 0.10-Hz systolic blood pressure variability, an index of sympathetic vasomotor tone. RESULTS: Subjects with social phobia, in contrast to nonanxious control subjects, manifested more anxiety, embarrassment, and somatic complaints in response to stress; however, physiological measures generally did not distinguish groups. Interaction effects indicated that socially phobic women were hyperresponsive to the stressor with respect to self-reported, hemodynamic, and autonomic parameters. Socially phobic men manifested no physiological differences in comparison with control subjects, but they reported more psychological and somatic complaints. CONCLUSIONS: Gender differences in subjective and physiological responses to a socially threatening situation indicate congruence between perceived social anxiety and physiological responses in older women but not men. We found no evidence of impaired cardiovascular autonomic regulation among socially phobic men despite other reports that phobically anxious men are at greater cardiovascular risk.

Aged↗
PubMedDate not supplied

Is the glass half empty or half full? A prospective study of optimism and coronary heart disease in the normative aging study.

OBJECTIVE: A sense of optimism, which derives from the ways individuals explain causes of daily events, has been shown to protect health, whereas pessimism has been linked to poor physical health. We examined prospectively the relationship of an optimistic or pessimistic explanatory style with coronary heart disease incidence in the Veterans Affairs Normative Aging Study, an ongoing cohort of older men. METHODS AND RESULTS: In 1986, 1306 men completed the revised Minnesota Multiphasic Personality Inventory, from which we derived the bipolar revised Optimism-Pessimism Scale. During an average of 10 years of follow-up, 162 cases of incident coronary heart disease occurred: 71 cases of incident nonfatal myocardial infarction, 31 cases of fatal coronary heart disease, and 60 cases of angina pectoris. Compared with men with high levels of pessimism, those reporting high levels of optimism had multivariate-adjusted relative risks of 0.44 (95% confidence interval = 0.26-0.74) for combined nonfatal myocardial infarction and coronary heart disease death and 0.45 (95% confidence interval = 0.29-0.68) for combined angina pectoris, nonfatal myocardial infarction, and coronary heart disease death. A dose-response relation was found between levels of optimism and each outcome (p value for trend,.002 and.0004, respectively). CONCLUSIONS: These results suggest that an optimistic explanatory style may protect against risk of coronary heart disease in older men.

Adult↗