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D Sparrow

Publications and source records attributed to D Sparrow.

At least 55 records · Page 3Linked to original sources
PubMed1997

Effects of obesity and fat distribution on ventilatory function: the normative aging study.

OBJECTIVE: Although the influence of obesity on ventilatory function has long been recognized, the nature of the relationship and the mechanisms are not yet clear. The purpose of this report was to examine the effects of overall obesity and fat distribution on ventilatory function. METHODS: Multiple measurements over > 30 years from 507 subjects with lifelong tobacco consumption of < or = 1 pack-year were analyzed separately in five age decades from 30 to 79 years. FVC, FEV1, ratio of FEV1 to FVC, and maximal midexpiratory flow rate (MMEF) were each adjusted for age and stature. Relative adiposity (or obesity) was assessed using the body mass index (BMI). Subscapular skinfold thickness, abdominal girth, and the ratio of abdominal girth to hip breadth (AG/HB) were used as measures of body fat distribution. Multiple linear regression was used to explore the effects of overall adiposity and body fat distribution on ventilatory function. RESULTS: BMI was positively associated with the ratio of FEV1 to FVC at all ages (p < 0.01), and negatively with FVC and MMEF between 40 and 69 years (p < 0.01). After adjustment for BMI, subscapular skinfold thickness was negatively associated with both FVC and FEV1 (p < or = 0.02) among men aged 30 to 59 years, whereas AG/HB was negatively associated with FVC and FEV1 in men aged 50 to 59 years only (p < or = 0.0004). CONCLUSIONS: Body fat distribution has independent effects on ventilatory function after adjustment for overall obesity in men. The finding that age modifies this association has implications for future research.

Adipose Tissue↗
PubMed1996

A prospective study of anger and coronary heart disease. The Normative Aging Study.

BACKGROUND: Recent laboratory and epidemiological studies have suggested that high levels of anger may increase the risk of coronary heart disease (CHD). METHODS AND RESULTS: We examined prospectively the relationship of anger to CHD incidence in the Veterans Administration Normative Aging Study, an ongoing cohort of older (mean age, 61 years) community-dwelling men. A total of 1305 men who were free of diagnosed CHD completed the revised Minnesota Multiphasic Personality Inventory (MMPI-2) in 1986. Subjects were categorized according to their responses to the MMPI-2 Anger Content Scale, which measures the degree to which individuals have problems controlling their anger. During an average of 7 years of follow-up, 110 cases of incident CHD occurred, including 30 cases of nonfatal myocardial infarction hostility. (MI), 20 cases of fatal CHD, and 60 cases of angina pectoris. Compared with men reporting the lowest levels of anger, the multivariate-adjusted relative risks among men reporting the highest levels of anger were 3.15 (95% confidence interval) [CI]: 0.94 to 10.5) for total CHD (nonfatal MI plus fatal CHD) and 2.66 (95% CI: 1.26 to 5.61) for combined incident coronary events including angina pectoris. A dose-response relation was found between level of anger and overall CHD risk (P for trend, .008). CONCLUSIONS: These data suggest that high levels of expressed anger may be a risk factor for CHD among older men.

Adrenergic beta-Antagonists↗
PubMed1996

Determinants of bone and blood lead levels among community-exposed middle-aged to elderly men. The normative aging study.

Levels of lead in bone serve as a dosimeter for cumulative exposure to lead; moreover, lead in bone may serve as an internal source of circulating lead many years after environmental exposure has ceased. The authors measured lead in blood and used a K-x-ray fluorescence instrument to measure lead in the tibia (cortical) and patella (trabecular) bones in a cross-sectional survey of 719 middle-aged to elderly male participants in the Normative Aging Study who were without unusual occupational exposures to lead and who were healthy when enrolled in 1962-1965. Blood lead levels ranged from < 1 to 27.9 micrograms/dl, with a geometric mean of 5.7 micrograms/dl. Tibia and patella lead level ranges (geometric means) were < 1-51 (20.8) micrograms/g and 3-77 (29.8) micrograms/g, respectively. In backwards elimination multivariate regression models that considered age, race, education, retirement status, measures of both current and cumulative smoking, and alcohol consumption, the factors that remained significantly related to higher levels of both tibia and patella lead were higher age and measures of cumulative smoking, and lower levels of education. In the final model predicting blood lead that began with these same covariates and also included tibia and patella lead, the factor that accounted for the dominant portion of the variance in blood lead was patella lead. After adjustment for measurement error, a rise in patella lead from the median of the lowest to the median of the highest quintiles (13-56 micrograms/g) corresponded to a rise in blood lead of 4.3 micrograms/dl. The authors conclude that bone lead levels are substantial and comprise the major source of circulating lead in these men.

Adult↗
PubMed1996

The relationship of bone and blood lead to hypertension. The Normative Aging Study.

OBJECTIVE: To test the hypothesis that long-term lead accumulation, as reflected by levels of lead in bone (as opposed to blood which reflects recent lead exposure), is associated with an increased odds of developing hypertension. DESIGN: Case-control study of participants in the Veterans Administration (now Department of Veterans Affairs) Normative Aging Study, a 30-year longitudinal study of men. PARTICIPANTS: Of 1171 active subjects who were seen between August 1991 and December 1994, 590 (50%) participated in this investigation and had data on all variables of interest. MAIN OUTCOME MEASURES: Hypertension was defined as taking daily medication for the treatment of hypertension or systolic blood pressure higher than 160 mm Hg or diastolic blood pressure of 96 mm Hg or higher during the time of examination. Levels of lead in the tibia (representing cortical bone) and the patella (representing trabecular bone) were measured in vivo with a K x-ray fluorescence (KXRF) instrument. Levels of lead in blood were measured by graphite furnace atomic absorption spectroscopy. RESULTS: Blood lead levels were low, ranging from less than 0.05 to 1.35 micromol/L (<1 to 28 microgram/dL), with a mean (SD) of 0.30 (0.20) micromol/L (6.3[4.1] microgram/dL). Bone lead levels were similar to those described in other general populations. In comparison to nonhypertensives, mean levels of lead in blood and both tibia and patella bone lead levels were significantly higher in hypertensive subjects. In a logistic regression model of hypertensive status that began with age, race, body mass index, family history of hypertension, history of ethanol ingestion, pack-years of smoking, dietary sodium intake, dietary calcium intake, blood lead, tibia lead, and patella lead, the variables that remained after backward elimination were body mass index, family history of hypertension, and level of lead in the tibia. An increase from the midpoint of the lowest quintile to the midpoint of the highest quintile of tibia lead from 3 to 37 micrograms per gram of bone mineral was associated with an increased odds ratio of hypertension of 1.5. CONCLUSION: Our findings suggest that long-term lead accumulation, as reflected by levels of lead in bone, may be an independent risk factor for developing hypertension in men in the general population.

Age Factors↗
PubMed1996

A longitudinal study of low-level lead exposure and impairment of renal function. The Normative Aging Study.

OBJECTIVE: To determine whether low-level lead exposure is associated with impaired renal function. DESIGN: Retrospective cohort study. SETTING AND PARTICIPANTS: Subjects were 459 men randomly selected from the participants of the Normative Aging Study who were originally recruited from healthy veterans in the greater Boston area in 1961 and were periodically examined at the Department of Veterans Affairs Outpatient Clinic every 3 to 5 years. We reconstructed blood lead concentrations for the period between 1979 and 1994 using samples of either archived red blood cells or fresh whole blood. MAIN OUTCOME MEASURES: Serum creatinine concentration. RESULTS: After adjustment for age, body mass index, smoking, alcohol consumption, educational level, and hypertension, blood lead concentration was positively and significantly associated with concurrent concentration of serum creatinine (P=.005). A 10-fold increase in blood lead level predicted an increase of 7 micromol/L (0.08 micrograms/dL) in serum creatinine concentration, which is roughly equivalent to the increase predicted by 20 years of aging. The association was also significant among subjects whose blood lead concentrations had never exceeded 0.48 micromol/L (10 micrograms/L) throughout the study period. The age-related increase in serum creatinine level was earlier and faster in the group with the highest-quartile levels of long-term lead exposure than in the group with the lowest-quartile levels. CONCLUSIONS: Low-level exposure to lead may impair renal function in middle-aged and older men. Longitudinal data suggest an acceleration of age-related impairment of renal function in association with long-term low-level lead exposure.

Age Factors↗
PubMed1996

The relationship of blood lead and dietary calcium to blood pressure in the normative aging study.

BACKGROUND: Previous studies have demonstrated a positive relationship between elevated blood lead (BPb) and blood pressure (BP), but few have additionally examined the role of dietary calcium. METHODS: The cross-sectional relationship between BPb and BP and the possible protective influence of increased dietary calcium on that relationship was examined among 798 male participants in the Normative Aging Study (NAS), a cohort of older men with relatively low BPb levels. RESULTS: The age range of these subjects was 43-93 years (mean = 66.1, SD = 7.4 years) and blood lead concentrations ranged form 0.5 to 35 mcg/dl (median = 5.6 mcg/dl). For the cohort overall, neither ln blood lead nor dietary calcium were significantly correlated with BP. In multivariate linear regression analyses that adjusted for age, body mass index, dietary calcium intake (adjusted for total calorie intake), alcohol intake, sitting heart rate, kilocalories/week expended in exercise, haematocrit, and smoking status, a unit increase in ln BPb predicted an increase on 1.2 mmHg diastolic blood pressure (DBP) (95% CI : 0.11, 2.2; P = 0.03). Adjusted calcium intake of 800 mg/day predicted a decrease of 3.2 mmHg systolic blood pressure (SBP) (95% CI : -5.6, -0.24, P = 0.03). There was no evidence of an interaction between dietary calcium intake and blood lead on BP. When the analyses were restricted to those men <=74 years old, a unit increase in ln BPb predicted an increase of 1.6 mmHg DBP (n = 681; 95% CI : 0.42, 2.7; P = 0.007). However, when men on antihypertensive medication (AHM) were excluded from the analyses, ln BPb was not significantly associated with increased DBP nor was adjusted calcium significantly associated with SBP. CONCLUSIONS: The study did support the hypothesis that increased BPb was associated with increased DBP in a cohort of older men with low blood lead, but there was no evidence of interaction between BPb and dietary calcium on BP. However, the relationship between increased BPb and DBP did not hold when those on anti-hypertensive medications were excluded.

Adult↗
PubMed1996

Hemodynamic consequences of obstructive sleep apnea.

Patients with obstructive sleep apnea demonstrate both acute and chronic hemodynamic changes attributable to their disease. Acutely, these patients experience repetitive nocturnal hemodynamic oscillations. Sudden increases in heart rate and arterial pressure occur in association with decreases in left ventricular stroke volume immediately following apnea termination. These hemodynamic changes are likely attributable primarily to the effects of oxygen desaturation and arousal, an abrupt change in state. These acute changes occur against a background of altered cardiovascular control. Patients with sleep apnea, even when sleeping without obstructions, fail to display the normal nocturnal decline in arterial pressure of 10-15% from the waking value. The absence of a nocturnal decline may have chronic consequences, such as development of left ventricular hypertrophy. Another chronic hemodynamic consequence of sleep apnea may be sustained diurnal hypertension. Epidemiologic studies suggest individuals with sleep disordered breathing are at greater risk of daytime hypertension, even after controlling for other risk factors. Although sleep apnea may contribute to pulmonary, as well as systemic hypertension, sleep apnea alone does not appear to be a cause of decompensated right heart failure. Although knowledge of the hemodynamic consequences of sleep apnea has grown in recent years, much remains to be learned.

Adult↗
PubMed1996

Influence of insulin, sympathetic nervous system activity, and obesity on blood pressure: the Normative Aging Study.

OBJECTIVE: To examine the association of insulin and sympathetic nervous system activity with blood pressure elevation in a cross-sectional study of 752 nondiabetic male participants of the Normative Aging Study, aged 43-90 years. METHODS: Testing included a physical examination, medical history, fasting and post-carbohydrate insulin and glucose levels determinations, an anthropometric examination, and 24 h urine collection for catecholamine level determination. Total obesity was represented by body mass index, central obesity by the abdomen circumference:hip circumference ratio, and sympathetic nervous system activity by 24 h urinary excretion of norepinephrine. RESULTS: Systolic and diastolic blood pressure (SBP and DBP, respectively) were positively related to body mass index, abdomen:hip ratio, norepinephrine excretion, and insulin levels in univariate analyses. The relationship between insulin level and SBP and DBP persisted after adjustment for body mass index, abdomen:hip ratio, norepinephrine, age, smoking, physical activity level, and antihypertensive medication use. The norepinephrine level was related to SBP and DBP after adjustment for insulin level, age, smoking, physical activity level, and antihypertensive medication use, and these relationships remained marginally significant after further adjustment for body mass index and abdomen:hip ratio. In contrast, neither body mass index nor abdomen:hip ratio were related to blood pressure after adjustment for insulin level. Among participants in the lowest tertiles both of insulin and of norepinephrine levels, 10% were hypertensive, compared with 35% in the highest tertiles of these variables. In a multiple logistic regression model, insulin level, norepinephrine level, and an interaction term for insulin level with norepinephrine excretion were independent predictors of hypertension. CONCLUSIONS: The results suggest that insulin level and sympathetic nervous system activity are associated with hypertension among middle-aged and elderly men.

Adult↗
PubMed1996

Relationship of serum IgE concentration to level and rate of decline of pulmonary function: the Normative Aging Study.

BACKGROUND: Previous reports on the relationship between serum immunoglobulin E (IgE) concentration and the level and rate of decline of pulmonary function in the general population have produced conflicting results. The relationship between total serum IgE concentration and pulmonary function was therefore examined in 1078 men aged 41-86 years followed in the Normative Aging Study. METHODS: The serum IgE concentration determined at the start of the three year follow up period was examined in relation to both the level and longitudinal rate of decline of forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC. RESULTS: In a cross sectional analysis restricted to subjects who had ever smoked cigarettes, multiple linear regression models indicated an inverse association between total serum IgE concentration and both FEV1 (beta = -0.090 1/log10 IU/ml; SE = 0.030; p < 0.005) and FVC (beta = -0.110 1/log10 IU/ml; SE = 0.034; p < 0.005) but not FEV1/FVC, after adjustment for age and height. This relationship persisted when individuals with diagnosed asthma or methacholine hyperresponsiveness were excluded. In subjects who had never smoked cigarettes the total serum IgE concentration was unrelated to spirometric indices. No association was observed in smokers or non-smokers between the serum IgE concentration measured at the beginning of the period of follow up and the decline in FEV1, FVC, or FEV1/FVC. CONCLUSION: Increased levels of serum IgE measured at the beginning of the follow up period are associated with lower levels of pulmonary function but are not predictive of an accelerated rate in the decline of pulmonary function among middle aged and older men.

Adult↗
PubMed1996

Skin test reactivity to common aeroallergens and decline of lung function. The Normative Aging Study.

It has been hypothesized that allergy is associated with an increased risk of developing chronic irreversible airflow obstruction. We have investigated the relation between immediate cutaneous hypersensitivity to common aeroallergens and the subsequent rate of decline of lung function in 1,025 men participating in the Normative Aging Study; subjects had a mean age of 61 +/- 8 (SD) yr and denied any history of asthma. Subjects performed spirometry and underwent allergen skin testing at a baseline visit and performed repeat spirometry after a median of 3.1 yr. Skin prick tests were performed using four glycerin-preserved allergens (house dust, mixed grasses, mixed trees, and ragweed); wheal size was measured at 20 min. Multiple linear regression analysis was used to examine the annual rate of change of lung function in relation to skin test reactivity, defined as a mean wheal size to the 4 allergens > or = 2 mm, after adjustment for age, height, smoking status, and initial lung function. Skin test reactivity was a significant predictor of the annual rates of decline of FEV1 and FEV1/FVC ratio. The regression model predicted an excess decline of FEV1 of 9.45 ml/yr for subjects with mean wheal diameter > or = 2 mm (p < 0.05); the excess rate of decline of FEV1/FVC ratio was 0.29 percent/yr (p = 0.001). There was no significant relation between mean wheal diameter and rate of decline of FVC. The magnitude of the effects of a mean wheal diameter > or = 2 mm on rates of decline of FEV1 and FEV1/FVC ratio are 34% and 49%, respectively, of the magnitude of the effects of current cigarette smoking in these models. We conclude that cutaneous hypersensitivity to common aeroallergens is a significant independent predictor of subsequent decline of lung function among middle-aged and older men with no history of asthma.

Aging↗
PubMed1996

Urinary desmosine excretion in smokers with and without rapid decline of lung function: the Normative Aging Study.

It is hypothesized that smoking-related chronic obstructive pulmonary disease (COPD) results in part from excess lung elastin degradation. Taking advantage of spirometry performed over a 12-yr period at the Normative Aging Study, we conducted a nested case-control study of elastin and collagen degradation rates in current smokers with (n = 10) and without (n = 8) rapid decline of lung function, using a biochemical assay for urinary desmosine (DES), a specific marker for mature elastin degradation, and hydroxylysylpyridinoline (HP), a specific marker for mature fibrillar collagen degradation. Mean urinary excretion of DES in rapid decliners was 36% greater than in slow decliners (9.8 +/- 0.7 [mean +/- SE] versus 7.2 +/- 0.4 microg/g creatinine, p < 0.01); after adjustment for age and lean body mass (LBM), DES excretion in rapid decliners was 30% greater than in slow decliners (9.6 +/- 0.6 versus 7.4 +/- 0.7 microg/g creatinine, p = 0.06). Among rapid decliners, there was no difference in DES excretion between those with and those without computed tomogaphic evidence of emphysema. There was no significant difference between rapid and slow decliners in mean urinary excretion of HP (24.7 +/- 1.4 versus 21.6 +/- 1.8 nmol/mmol creatinine, p = 0.18). Among all subjects, rate of decline of FEV1 was significantly correlated with DES excretion (r = 0.61, p < 0.01). In a linear regression model adjusting for age and LBM, an increase in DES excretion of 1 microg/g creatinine was associated with an excess decline of FEV1 of 10.6 ml/yr (p = 0.04). This study provides further evidence in support of the elastase-antielastase hypothesis of the pathogenesis of COPD, and it suggests a role for elastin degradation in both emphysema and small airways disease. Moreover, it suggests that urinary DES excretion may be a useful biochemical marker for the study of interventions designed to prevent the development or progression of COPD.

Aged↗
PubMed1995

Longitudinal models for analysis of respiratory function.

We compare the results of fitting three longitudinal models, two autoregressive models (the serial correlation model and a damped autoregressive model) and a compound symmetry model, to data on a cohort of 1154 adult men in Boston. The serial correlation model assumes that the error terms are autocorrelated with correlation of the form lambda t for visits t years apart while the damped autoregressive assumes that the correlation between error terms of observations t years apart is of the form lambda t theta. The compound symmetry model assumes that the errors are correlated, with the same correlation regardless of how far apart observations are in time. These three models are all related in that the serial correlation and compound symmetry models are particular cases of the damped autoregressive models (that is, theta = 1 corresponds to the serial correlation model and theta = 0 corresponds to the compound symmetry model). For current smokers, the damped autoregressive model provided a significantly better fit than either of the other two models (p < 0.001); for never smokers the damped autoregressive and compound symmetry models were almost identical with both providing a significantly better fit than the serial correlation model (p < 0.001).

Adult↗
PubMed1995

Relation of FEV1 and peripheral blood leukocyte count to total mortality. The Normative Aging Study.

Increased peripheral blood leukocyte count and decreased level of pulmonary function have both been implicated as causes of increased total mortality in population-based studies. The extent to which these factors are independent of cigarette smoking is controversial. The authors explored the relation of leukocyte count and the level of forced expiratory volume in 1 second to total mortality in the Normative Aging Study population in the Boston, Massachusetts, area. Other covariates examined included forced vital capacity, height, body mass index, systolic and diastolic blood pressure, and total cholesterol. The sample for the current analysis consisted of 1,956 men who underwent the baseline Normative Aging Study examination during 1961-1969. Subjects ranged in age from 21 to 80 years of age at the time of entry. A total of 170 deaths occurred over the 30 years of follow-up. Statistical analysis was conducted utilizing Cox proportional hazards modeling and regression trees for censored survival data. The Cox proportional hazards model suggested that age, forced expiratory volume in 1 second, and peripheral blood leukocyte count were the three most important predictors of increased mortality in this cohort. A regression tree analysis in general confirmed these results. Both methods of analysis suggest that forced expiratory volume in 1 second and peripheral blood leukocyte count were predictors of mortality, independent of cigarette smoking.

Adult↗
PubMed1995

Uric acid and coronary heart disease risk: evidence for a role of uric acid in the obesity-insulin resistance syndrome. The Normative Aging Study.

Various epidemiologic studies have linked an increase in serum uric acid level to an increased risk of coronary heart disease. The reasons for this finding are unclear. The authors examined the influence of a number of cardiovascular disease risk factors on serum uric acid level in 886 middle-aged and older men participating in the Normative Aging Study. The men were examined between 1987 and 1991. In a multivariate regression model predicting serum uric acid level, uric acid was positively associated with body mass index (weight (kg)/height (m)2 beta = 0.041 mg/dl per kg/m2, p = 0.003), abdomen: hip circumference ratio (beta = 1.88 mg/dl per cm/cm, p = 0.048), log alcohol intake (beta = 0.150 mg/dl per g/week, p = 0.0001), and log postcarbohydrate insulin level (beta = 0.157 mg/dl per log(microIU/ml), p = 0.005). Serum uric acid level was negatively associated with age (beta = -0.012 mg/dl per year of age, p = 0.017) and log physical activity (beta = -0.152 mg/dl per kcal/week, p = 0.0001). The data suggest that serum uric acid may be involved in the obesity-insulin resistance syndrome, which in turn may explain the relation of serum uric acid to coronary atherosclerosis.

Adult↗
PubMed1995

Decreased heart rate variability in men with phobic anxiety (data from the Normative Aging Study).

Prospective cohort studies suggest that phobic anxiety is a strong risk factor for fatal coronary artery disease, in particular, sudden cardiac death. It has also been established that reduced heart rate (HR) variability can identify patients at high risk for subsequent sudden cardiac death. We therefore hypothesized that persons with symptoms of phobic anxiety may exhibit reduced HR variability. We tested our hypothesis in 581 men, aged 47 to 86 years, enrolled in the Normative Aging Study who were free of coronary artery disease and diabetes. Symptoms of anxiety were assessed using the Crown-Crisp index, an instrument that has been demonstrated in previous prospective studies to strongly predict risk of sudden cardiac death. HR variability was measured under standardized conditions, with paced deep breathing (6 breaths/1 min). Two measures of HR variability were used: the SD of HR and the maximal minus minimal HR over 1 minute. Men reporting higher levels of phobic anxiety had a higher resting HR (p = 0.025 for linear trend). After adjusting for age, mean HR, and body mass index in analyses of covariance, men reporting higher levels of phobic anxiety had lower HR variability, whether measured by the SD of HR (p = 0.03 for linear trend). These data suggest that phobic anxiety is associated with altered cardiac autonomic control, and hence increased risk of sudden cardiac death.

Aged↗
PubMed1995

The relationship between heart rate variability and measures of body habitus.

There is a well-recognized relationship between autonomic nervous system function and body habitus although few studies have addressed the role of the parasympathetic nervous system. A decrease in parasympathetic nervous-system-mediated heart rate variability in obesity may in part explain the mortality and morbidity that are associated with the obese state. We used multiple linear regression techniques to explore the relationship between measures of heart rate variability and anthropometric indices in 597 male participants in the Normative Aging Study. After adjustment for age and log10 heart rate, weight and body mass index were significant predictors of both the expiratory to inspiratory ratio (E/I ratio) and the difference between maximum and minimum heart rate (HRMax-Min). The abdomen-to-hip ratio and percentage body fat were not significant predictors of measures of heart rate variability. A one standard deviation change in the anthropometric index (weight, body mass index) resulted in a decrease in the E/I ratio of 0.010-0.014 and a decrease in the HRMax-Min of 0.486-0.715 beats/min. A change in the anthropometric index across the distribution (5-95 percentile) resulted in a decrease in the E/I ratio of 0.032-0.037 and a decrease in the HRMax-Min of 1.56-2.39 beats/min. These results indicate that heart rate variability and overall body size are correlated. This association could in part explain the mortality and morbidity that is associated with the obese state.

Adipose Tissue↗