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L DiPietro

Publications and source records attributed to L DiPietro.

33 records · Page 2Linked to original sources
PubMed1997

Mechanism of attenuated thirst in aging: role of central volume receptors.

To test the hypothesis that the inhibitory action of central blood volume expansion on thirst and renal fluid regulation is attenuated with aging, we monitored the drinking and renal responses of dehydrated older (70 +/- 2 yr, n = 6) and younger (24 +/- 1 yr, n = 6) subjects during 195 min of head-out water immersion (HOI), which shifts blood centrally and increases plasma volume (PV). Subjects dehydrated by exercising for 2 h at 36 degrees C in the evening and refraining from fluids overnight before HOI in 34 degrees C water or a seated control in water perfusion suit [time control (TC)] the next morning. Ad libitum water intake was allowed after 15 min of HOI. Dehydration decreased PV by 10.6 +/- 1 and 7.3 +/- 1.8% (P < 0.05) and increased plasma osmolality by 6 +/- 2 and 7 +/- 1 mosmol/kg H2O (P < 0.05) in older and younger subjects, respectively. Thirst ratings increased in both groups, but pre-HOI thirst perception on a line rating scale was lower in older (69 +/- 8 mm) than younger (94 +/- 6 mm, P < 0.05) subjects. Fifteen minutes of HOI restored PV by 7.8 +/- 1.0 and 5.7 +/- 1.0% in older and younger subjects, respectively, but suppressed thirst rating in younger subjects only (P < 0.05). Fluid intake was reduced in HOI compared with TC in younger (6.3 +/- 0.5 vs. 14.3 +/- 2.2 ml/kg, P < 0.05) but not in older (6.7 +/- 2.1 vs. 8.4 +/- 3.3 ml/kg) subjects. During HOI, older subjects had smaller suppression of plasma renin activity and aldosterone concentration but a greater increase in the plasma atrial natriuretic peptide concentration (P[ANP], P < 0.05). HOI increased fractional sodium excretion in both groups, but mean arterial pressure increased only in the older subjects (P < 0.05). We conclude that the inhibitory influence of central volume expansion on thirst and drinking behavior is diminished with aging. Furthermore, in contrast to younger people, HOI natriuresis is associated with exaggerated increases in P[ANP] and arterial blood pressure in older people, suggesting arterial baroreceptors may be involved in the fluid regulatory response to central blood volume expansion in older people.

Adult↗
PubMed1996

The epidemiology of physical activity and physical function in older people.

A primary goal of studies of successful aging is to identify the modifiable factors related to the plasticity of higher physical function; however, little is known about the relationship between habitual physical activity (especially that of lower- to moderate-intensity) and the maintenance of day-to-day functioning in older people. The purpose of this paper is to address the question of how patterns of physical activity translate into altered physical function among healthy older populations. In this paper, physical activity is classified as a behavior, whereas physical function is classified as performance, comprised of a series of increasingly integrated steps. Recent data from several epidemiologic studies suggest that physical activity is associated with the maintenance of more basic components of physical function, as well as with higher-order task or goal-oriented functions in healthy older people. Moreover, higher levels of physical activity appear to be associated with better functioning, even in those with already-existing chronic disease. Recent CDC/ACSM health recommendations call for incorporating at least 30 min of any activity into the daily schedule. Therefore, regular participation in activities of moderate intensity (such as walking, gardening, house/yard work) should be encouraged among the general older community.

Activities of Daily Living↗
PubMed1996

Thirst and fluid regulatory responses to hypertonicity in older adults.

To assess the fluid regulatory responses in aging adults, we measured thirst perception and osmoregulation during and after infusion of hypertonic NaCl) saline in older (72 +/- 2 yr, n = 6) and younger (26 +/- n = 6) subjects. Hypertonic saline was infused at 0.1 min-1.kg-1 for 120 min. On a separate day, the same subjects were infused identically with isotonic saline as a control. After infusion and a 30-min equilibration period, the drank water ad libitum for 180 min. Hypertonic infusion led to graded increases in plasma osmolality (Posm; 18 +/- 2 and 20 +/- 2 mosmol/kgH2O) and percent changes plasma volume (16.2 +/- 1.9 and 18.0 +/- 1.2%) that were in older and younger subjects. Osmotically stimulated increases in thirst (94.8 +/- 18.9 and 88.3 +/- 25.6 mm), assessed on a line rating scale, and plasma arginine vasopressin concentration (6.08 +/- 1.50 and 4.51 +/- 1.37 pg/ml, for older younger, respectively) were also unaffected by age. subsequent hypervolemia, both groups of subjects sufficient water to restore preinfusion levels of Posm. Renal handling of free water and sodium was also unaffected by age during recovery from hypertonic saline infusion, but was significantly lower in older subjects during recovery from saline infusion, resulting in net fluid retention and a significant fall in Posm (6 mosmol/kgH2O). In contrast to earlier reports of a blunted thirst response to dehydration hypertonicity, we found that osmotically stimulated thirst and renal osmoregulation were intact in older adults after hypertonic saline infusion.

Adult↗
PubMed1995

Physical activity, body weight, and adiposity: an epidemiologic perspective.

Overweight is a common problem in the United States, especially among minority women and persons of lower socioeconomic status and lower educational attainment. Moreover, the prevalence of reported inactivity may be highest in these same population subgroups. Both overweight and sedentary behavior are important risk factors for chronic disease morbidity and mortality; however, there is encouraging evidence that moderate to higher levels of physical activity may provide protection from certain chronic diseases, even among persons with established risk factors. Several methodological issues preclude the ability to determine accurately the impact of physical activity on body weight and adiposity. These issues include (a) a low prevalence of higher-intensity physical activity in the general population, (b) measurement error with regard to self-reported activity, especially that of lower-intensity, (c) inappropriate time frame of the physical activity assessment, (d) effect modification by age and gender, and (e) failure to adjust for important statistical confounders. Despite these methodological issues, the inverse association between physical activity and weight has been reported in several cross-sectional epidemiologic studies, which consistently report lower body weight, or more favorable distribution of body fat, with higher categorical levels of self-reported physical activity. Directionality of the physical activity and weight relation cannot be determined from these studies, however, and the few longitudinal epidemiologic studies that have assessed the influence of physical activity on the risk of weight gain report inconclusive results. This is possibly because a one-time assessment of physical activity if not adequate in describing the contribution of habitual physical activity on long-term weight maintenance. Therefore, longitudinal population-based studies with multiple assessments of physical activity over long follow-up periods are necessary to determine this relationship. In any case, the evidence suggests that persons concerned with overweight, or especially the prevention of overweight and obesity, should increase their physical activity. Sociodemographic characteristics such as age, gender, educational level, and weight are associated with physical activity patterns and choices. Therefore, these characteristics should be considered by professionals when implementing physical activity interventions for weight control. Walking is accessible to all segments of the U.S. population. Because walking is convenient, low cost, and safe, and can result in weight loss if done regularly for durations of at least 20-30 min, its relative merits should be stressed in weight reduction and maintenance programs. Furthermore, to reduce the morbidity and mortality associated with overweight, obesity, and sedentary behavior, priority for intervention programs should be directed at persons in the most vulnerable sectors of the population.

Adipose Tissue↗
PubMed1994

Adiposity and stroke among older adults of low socioeconomic status: the Chicago Stroke Study.

OBJECTIVES: The purpose of this study was to test the hypothesis that overall and truncal adiposity increase the risk of stroke independent of their association with cardiovascular disease risk factors and other preexisting illnesses. METHODS: Analyses were conducted of longitudinal data from a poor, biracial cohort of noninstitutionalized adults 65 to 74 years of age who participated in the Chicago Stroke Study from 1965 to 1970. RESULTS: Ponderal index (cm/kg1/3) and chest skinfold were significantly associated with systolic and diastolic blood pressure, serum cholesterol and triglycerides, plasma glucose, and smoking. Ponderal index was also associated with diabetes and risk of stroke. After potential confounders were controlled, the following variables showed significant independent associations with risk of stroke: Black race, female gender, and age 70+; hypertensive heart disease; and diabetes. Neither adiposity variable was associated with risk of stroke in the presence of these powerful predictors. CONCLUSIONS: Control of hypertension and diabetes continues to be important among older adults. Since excess adiposity seems to influence risk of stroke through its association with these disorders and other cardiovascular disease risk factors, control of weight and fat remains an important concern as well.

Aged↗
PubMed1994

A 40-year history of overweight children in Stockholm: life-time overweight, morbidity, and mortality.

We describe the 40-year weight history and adult morbidity and mortality in a cohort of 504 overweight children, aged 2 months to 16 years, who were admitted for investigation of their overweight to four children's hospitals in Stockholm between 1921 and 1947. Follow-up information was gathered by questionnaire at 10-year intervals, most recently in 1980-1983 (n = 458), on weight history (based on the body mass index (BMI = kg/m2)), as well as prevalence of cardiovascular disease (n = 143), diabetes (n = 39), and cancer (all types (n = 20)), reported during the 40 years of follow-up, and mortality from all causes (n = 55), determined from death certificate. The sample of overweight children remained overweight as adults; after age 55 years, the BMI began to decline for both genders. Female subjects were heavier than their male counterparts from postpuberty onward. Subjects who died by the 40-year follow-up and those reporting cardiovascular disease were significantly (P < or = 0.05) heavier at puberty and in adulthood than were healthier subjects. There was a marked increase in the BMI between postpuberty and age 25 among those who subsequently died, those who developed cardiovascular disease, and particularly among those who developed diabetes (P < or = 0.001). In contrast, those reporting cancer had a lower BMI throughout adulthood than those who did not. We conclude that overweight in adolescence may continue into adulthood and may be associated with subsequent adverse health outcomes.

Adolescent↗
PubMed1993

Body mass and risk of hip fracture among a national cohort of postmenopausal white women: a reanalysis.

To assess the prospective relationship between body mass and rate of hip fracture, we analyzed data from 2,285 postmenopausal women, aged 50-77 years, who responded to the first National Health and Nutrition Examination Survey (NHANES I) in 1971-1974 and the 1982-84 interview of the National Health Epidemiologic Follow-up Study (NHEFS). We plan to add to the previous analysis of these same data by Farmer et al. by 1) including retrospective information on estrogen replacement therapy; 2) increasing the follow-up time by 5 years and using only hospital-verified cases of hip fracture from the 1987 Health Care Facilities Stay data tape; and 3) limiting the analysis to postmenopausal white women, ages 50-77 years. Results of the multivariable Cox regression modeling showed that women with a baseline body mass index in the highest quartile (> 37 kg/m1.5) experienced a 70% lower rate of hip fracture compared with women in the lowest quartile (< or = 28.7 kg/m1.5)(RR=0.32; 95%CI:0.12, 0.82). Age was positively related to the risk of hip fracture, with the rate over 20% higher per year of age (RR=1.21; 95%CI:1.13, 1.29). Although reported education level, smoking history, physical activity level, and estrogen replacement were significantly (p < 0.0001) associated with body mass index, these covariates were not related to hip fracture in the multivariable analysis. Our findings corroborate earlier results using this same data source, and suggest that interventions aimed at preserving lean mass and consequent bone integrity should be encouraged among women before menopause and maintained through older adulthood.

Age Factors↗
PubMed1993

The descriptive epidemiology of selected physical activities and body weight among adults trying to lose weight: the Behavioral Risk Factor Surveillance System survey, 1989.

Few population-based studies have described the physical activity patterns of individuals trying to lose weight. We analysed cross-sectional, self-reported data from 6125 men and 12,557 women (> or = 18 years of age) from 40 states who reported in the 1989 Behavioral Risk Factor Surveillance System (BRFSS) survey that they were trying to lose weight. The BRFSS is a state-based telephone survey of non-institutionalized US adults, which utilizes a multi-stage cluster design based on the Waksberg method of random digit dialing. Walking was the most prevalent physical activity (48%), followed by aerobics (8%), gardening (5%), cycling (5%), and running (4%); however, activity choices varied by socio-demographic characteristics. Among both sexes, the prevalence of overweight (BMI > or = 30 kg/m2) decreased significantly with increasing level of activity (P < or = 0.001). Regression results showed that among both sexes and in most age groups, those who ran or jogged, performed aerobics, or cycled weighed less (P < or = 0.001) than those who reported no activity--independent of height, race, education, smoking, and caloric restriction. Walking was also associated with lower weight (P < or = 0.001) among persons aged 40 or older. Because walking is highly prevalent among persons in most socio-demographic strata and is accessible and low risk, its relative merits should be stressed in developing interventions for weight loss and maintenance.

Adult↗
PubMed1992

Depressive symptoms and weight change in a national cohort of adults.

To assess the influence of depressive symptoms (defined using the CES-D) on weight change, we analysed data from 1794 adults, aged 25-74 years, who participated in the first National Health and Nutrition Examination Survey in 1971-1975 and the National Health Epidemiologic Follow-up Study in 1982-1984. After adjusting for baseline covariates using multiple linear regression, the data show that younger men (< 55 years) who were depressed at baseline gained nearly 3 kg more over the follow-up period than those who were not depressed. Among these younger men, however, education modified the effect of depression on weight change; those with < 12 years of education gained more weight with depression than those with more education (6.2 vs. 1.2 kg, respectively; P < or = 0.01). In contrast, depressed younger women gained slightly less weight than those who were not depressed. Among younger women, education also modified the effects of depression on weight change; those with < 12 years of education gained less weight with depression than those with more education (-3.2 vs. 0.6 kg, respectively; P < or = 0.01). Among older people (> or = 55 years), both men and women who were depressed lost more weight than those who were not depressed. Depression may play a substantial role in the patterns of weight change among adults in the United States. These patterns of weight change may contribute to the adverse health effects associated with depression.

Adult↗
PubMed1988

Determinants of pediatric injuries.

Injuries are an important health issue for children. Previous research, however, has presented confusing and conflicting results on the determinants of childhood injuries, particularly psychosocial predictors, largely due to methodologic problems. The purpose of this analysis, based on a prospective follow-up study of 532 children, was to identify factors related to injuries encountered in a prepaid group practice during a 12-month period. Using logistic regression, we found four factors independently associated with the risk of at least one treated injury: high activity level, high rate of pediatric utilization for non-injury-related visits during the follow-up period, occurrence of a treated injury during the year preceding the follow-up period, and negative attitude toward medical care providers by the child's mother. In addition, four factors were found to be independent predictors of injuries judged severe enough to always warrant medical care: occurrence of a treated injury in the preceding year, high rate of pediatric utilization for non-injury-related visits during the follow-up period, working more than 15 hours a week outside the home by the child's mother, and more life events reported by the mother for the year preceding the follow-up period. Since family stressors are related specifically to the risk of more severe injuries, which are unlikely to escape medical attention, we conclude that these factors probably are related to the occurrence of common injuries of early childhood and not exclusively to utilization behavior. We therefore suggest that children from families with these characteristics be targeted for injury prevention strategies.

Attitude↗
PubMedDate not supplied

Mood and body weight in a woman with rapid cycling bipolar disorder: a case report.

To describe the relationship between mood and body weight, we analyzed 122 consecutive days of data from a 52-year-old woman with rapid cycling bipolar disorder, type II. The patient completed a daily log of self-reported mood, and weighed and recorded her weight daily. Mood and body weight were highly correlated (r = 0.60), and a decrease in mood preceded a decline in body weight by 3 days. Reports of loss of appetite on the Hamilton Depression Rating Scale also corresponded to periods of weight loss. There was a negligible difference in the patient's resting metabolic rate between a period of depression (1628 kcal/day) and of euthymia (1724 kcal/day). The association between depression and weight loss was primarily mediated by decreased food intake. Such patients should provide an excellent opportunity to study the regulation of body weight with affective illness.

Affect↗