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Biomedical subjects

A S Ryan

Publications and source records attributed to A S Ryan.

At least 55 records · Page 3Linked to original sources
PubMed1994

Strength training increases insulin action in healthy 50- to 65-yr-old men.

The insulin resistance associated with aging may be due, in part, to reduced levels of physical activity in the elderly. We hypothesized that strength training increases insulin action in older individuals. To test this hypothesis, 11 healthy men 50-63 yr old [mean 58 +/- 1 (SE) yr] underwent a two-step hyperinsulinemic-euglycemic glucose clamp with concurrent indirect calorimetry and an oral glucose tolerance test (OGTT) before and after 16 wk of strength training. The training program increased overall strength by 47% (P < 0.001). Fat-free mass (FFM; measured by hydrodensitometry) increased (62.4 +/- 2.1 vs. 63.6 +/- 2.1 kg; P < 0.05) and body fat decreased (27.2 +/- 1.8 vs. 25.6 +/- 1.9%; P < 0.001) with training. Fasting plasma glucose levels and glucose levels during the OGTT were not significantly lower after training. In contrast, fasting plasma insulin levels decreased (85 +/- 25 vs. 55 +/- 10 pmol/l; P < 0.05) and insulin levels decreased (P < 0.05, analysis of variance) during the OGTT. Glucose infusion rates during the hyperinsulinemic-euglycemic glucose clamp increased 24% (13.5 +/- 1.7 vs. 16.7 +/- 2.2 mumol.kg FFM-1.min-1; P < 0.05) during the low (20 mU.m-2.min-1) insulin infusion and increased 22% (55.7 +/- 3.3 vs. 67.7 +/- 3.9 mumol.kg FFM-1.min-1; P < 0.05) during the high (100 mU.m-2.min-1) insulin infusion. These increases were accompanied by a 40% increase (n = 7; P < 0.08) in nonoxidative glucose metabolism during the high insulin infusion. These results demonstrate that strength training increases insulin action and lowers plasma insulin levels in middle-aged and older men.

Aged↗
PubMed1994

Effects of strength training on bone mineral density: hormonal and bone turnover relationships.

The effects of a 16-wk strength-training program on bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry in 21 men [age 61 +/- 1 (SE) yr]. Sixteen men (age 59 +/- 2 yr) served as control subjects. To investigate the possible hormonal relationships underlying the effects on BMD, serum concentrations of growth hormone, insulin-like growth factor I, and testosterone were determined before and after training. In addition, osteocalcin and skeletal alkaline phosphatase (markers of bone formation) and tartrate-resistant acid phosphatase (a marker of bone resorption) were measured before and after training to assess bone turnover. The training program resulted in a 2.8 +/- 0.6% increase in femoral neck BMD (1.004 +/- 0.037 vs. 1.031 +/- 0.037 g/cm2; P < 0.001). However, there were no significant changes in total body, anterioposterior spine, lateral spine, Ward's triangle, or greater trochanter BMD. Moreover, there were no significant changes in growth hormone, insulin-like growth factor I, testosterone, osteocalcin, or skeletal alkaline phosphatase. There were no changes in the control group. Thus, strength training can increase femoral neck BMD, and this effect does not appear to be accompanied by changes in anabolic hormones or markers of bone formation and resorption.

Absorptiometry, Photon↗
PubMed1993

Nutrition screening and assessment: current practices and dietitians' leadership roles.

OBJECTIVE: To ascertain hospital nutrition screening and assessment practices and the need for additional resources to facilitate these processes. DESIGN: A survey questionnaire was developed to ascertain screening protocols, assessment procedures and tools, relevant training and research needs, and respondent characteristics. SAMPLE: The survey was sent to 988 members of Dietitians in Nutrition Support, a dietetic practice group of The American Dietetic Association; 388 (39.3%) responses were used for analysis. STATISTICAL ANALYSIS: Descriptive statistics were used to calculate response frequency. chi 2 Statistics were used to test associations between nutrition assessment practices and association membership, nutrition support team activity, patient load, time allocations, and type and size of hospital. RESULTS: Most institutions had policies for screening (90.2%); 68.7% of dietitians were involved in screening either alone or with others. Assessment practices within hospitals varied widely: 45.9% used a standard form; 66.8% assessed patients at risk; and 10.6% assessed all patients. Typical assessments included height and weight, diagnosis, weight history, albumin, food intolerance, and allergies. Social histories and sophisticated methods such as indirect calorimetry were used infrequently. Most assessments (54.5%) took 31 to 59 minutes; 35.0% of the dietitians spent more than half their time doing assessments. A large percentage (48.7%) of respondents viewed the dietitian as having greatest influence on assessment policies; others thought physicians (23.2%), administrators (15.7%), nurses (6.2%), or pharmacists (6.5%) had the greatest influence. APPLICATIONS/CONCLUSIONS: Recommended improvements include improved standards of practice, development of written protocols and practice guidelines, better use of human resources, standardization of assessment procedures throughout the profession, and empowerment of dietitians to assume a stronger leadership role in this dimension of dietetics practice.

Anthropometry↗
PubMed1992

Nutrient intakes and dietary patterns of older Americans: a national study.

To assess the dietary status of older Americans, a national household survey of food consumption practices of individuals 65 years of age and older was conducted in May-August, 1990. The design and methodology of the survey were modeled after those of the USDA's Continuing Survey of Food Intakes by Individuals (CSFII). Dietary information for 474 individuals (65 to 98 years of age) in 355 households was collected by interview (24-hour dietary recall). Analyzed indicators of dietary quality were energy (calorie) and nutrient intake, food group intake and frequency, and number of meals skipped. Results indicated that substantial percentages of those surveyed had inadequate intakes of energy and nutrients. Over 40% of men had intakes of vitamins A and E, calcium, and zinc below two-thirds the RDA. For women, over 40% had intakes of vitamin E, calcium, and zinc that were below two-thirds the RDA. Additionally, over 20% of older men and women skipped lunch. These data indicate that a large proportion of noninstitutionalized elderly Americans consume diets that fail to meet dietary standards.

Aged↗
PubMed1991

Decreased stature associated with moderate blood lead concentrations in Mexican-American children.

The relationship of blood lead concentration to stature was evaluated by examining data from a sample of 1454 Mexican-American children aged 5-12 y, derived from the data sets of the Hispanic Health and Nutrition Examination Survey (HHANES) conducted in 1982-1984. The results indicate that there is an inverse relationship between blood lead concentration in the range 0.14-1.92 mumol/L with stature. The present finding suggests that growth retardation may be associated even with moderate concentrations of blood lead. Therefore, permissible exposure levels of lead for children deserve reexamination in light of the present analysis.

Age Factors↗
PubMed1991

A comparison of breast-feeding data from the National Surveys of Family Growth and the Ross Laboratories Mothers Surveys.

This study compares rates of breast feeding reported in the National Surveys of Family Growth with those from the Ross Laboratories Mothers Surveys. Both surveys have documented rates of breast feeding over the last 30 or more years. Despite differences in survey methodology, both surveys document similar long-term trends in breast feeding. The similarities of rates in breast feeding also are evident across several maternal sociodemographic characteristics. We conclude that both surveys produce reliable and useful estimates of breast feeding.

Adult↗
PubMed1991

Recent declines in breast-feeding in the United States, 1984 through 1989.

Ongoing surveys performed by Ross Laboratories demonstrate recent declines both in the initiation of breast-feeding and continued breast-feeding at 6 months of age. Comparing rates in 1984 and 1989, the initiation of breast-feeding declined approximately 13% (from 59.7% to 52.2%), and there was a 24% decline in the rate of breast-feeding at 6 months of age (from 23.8% to 18.1%). The decline in breast-feeding was seen across all groups studied but was greater in some groups than in others. Logistic regression analysis indicates that white ethnicity, some college education, increased maternal age, and having an infant of normal birth weight were all positively associated with the likelihood of both initiating breast-feeding and continuing to breast-feed to at least 6 months of age. Women who were black and who were younger, no more than high school educated, enrolled in the Women, Infants and Children supplemental food program, working outside the home, not living in the western states, and who had an infant of low birth weight were less likely either to initiate breast-feeding or to be nursing when their children were 6 months of age. The factors influencing the decline in breast-feeding were not uniform. There were fewer sociodemographic factors associated with the decline in the initiation of breast-feeding than in the decline in prolonged breast-feeding. While the disparity between older and younger mothers in initiating breast-feeding increased, there was an offsetting trend as the disparity associated with parity decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗
PubMed1991

Image and role of the consultant dietitian in long-term care: results from a survey of three Midwestern States.

Consultant dietitians and other health care professionals in three states were surveyed to determine the image and role of consultant dietitians in long-term care. Data were derived from telephone interviews with nursing home personnel in Illinois, Indiana, and Ohio. Chi 2 Analysis was used to determine whether health professionals' perceived image and job functions of consultant dietitians were significantly different from the perceptions of consultant dietitians. Overall, respondents held positive views of consultant dietitians. More than half of the respondents said the image of consultant dietitians had improved over the past 5 years. More than half of nursing directors, dietitians, dietary managers, and medical directors responded that consultant dietitians spent adequate time in facilities to do their jobs. Results of the study indicate that consultant dietitians believe that they are viewed by other health professionals as they actually are: competent, knowledgeable, well-respected, and involved in direct patient care functions. The next challenge is for more consultant dietitians to build on this base and become proactive, developing strong franchises and more opportunities for the profession.

Attitude of Health Personnel↗
PubMed1990

Duration of breast-feeding patterns established in the hospital. Influencing factors. Results from a national survey.

Data from a national survey of new mothers were analyzed to determine the effect that demographic characteristics, breast-feeding instructions, and infant formula discharge kits had on breast-feeding patterns established in the hospital. Results indicated that mothers who exclusively breast-fed their infant were more likely to be affluent, college educated, and not working outside the home. Mothers who exclusively breast-fed their infants in the hospital and subsequently practiced partial breast-feeding or formula, or cow's milk feeding were more likely to return to the work force within the first 6 postpartum months. Mothers who partially breast-fed their infants in the hospital were more likely to have a low-birth-weight neonate. Stepwise logistic regression analysis indicated that greater total family income, a better education, and having more than one child had positive significant effects on exclusive breast-feeding by the first and fourth month. Women who received a formula discharge kit compared with those who did not had a slightly higher probability of initiating partial breast-feeding (10 vs. 7% by the first month; 27 vs. 25% by the fourth month). Maternal employment had a large impact on duration of exclusive breast-feeding. By the fourth month, mothers who were employed had a higher probability of initiating partial breast-feeding (43 vs. 19%) compared with mothers who were not in the work force.

Animals↗
PubMed1989

The pediatric marketplace.

This study presents an overview of the demography of office-based pediatricians, trends in the patient population, and the growth of the pediatricians' market share of children seeking primary medical care. The following four factors bear directly on the present and future status of the office-based pediatric practice: (1) size of the office-based pediatrician population, (2) size of the pediatric patient population, (3) the frequency of patient visits, and (4) the pediatric market share. Results indicate that the pediatricians' market share of young children has continued to grow. However, the pediatricians' share of young children has not grown fast enough to offset an increase in the pediatrician population. Continued growth of the pediatric practice may depend on developing effective marketing strategies and providing more primary care to the adolescent population.

Adolescent↗
PubMed1989

Breast-feeding and the working mother: a profile.

Based on a survey of a nationally representative sample of new mothers, this study compares the incidence and duration of breast-feeding among mothers who were employed full-time outside the home with those not employed. Results indicated that the same proportion of mothers (55%) who were employed full-time as those not employed reported breast-feeding their infants in the hospital. Working full-time seemed to have a substantial impact on breast-feeding duration. Only 10% of full-time employed mothers breast-fed their infants at 6 months of age compared with 24% of those not employed. Analyses of breast-feeding by demographic characteristics indicated that in-hospital breast-feeding was relatively high among mothers who were not working outside the home and who were 30 years of age and older, in high family income groups, college educated, white, and living in the Mountain or Pacific region of the United States. Breast-feeding patterns among white and black mothers showed that a relatively high incidence of in-hospital breast-feeding was reported by black mothers who returned to work full time. Many more blacks than whites who were working full time were in those demographic subgroups that reported the highest incidence of breast-feeding: mothers who were 25 years of age and older, in high-income groups, and college educated. Ways to increase the level of breast-feeding among employed mothers are outlined.

Adult↗
PubMed1988

The role of the clinical dietitian: I. Present professional image and recent image changes.

This study was designed to assess the image of dietitians in the hospital setting. Fifty persons in each of six health professions responded to a telephone questionnaire. The six health professions were nutrition support dietitians, general clinical dietitians, directors of nursing, hospital administrators, chief dietitians, and physicians. Respondents were selected from relatively large hospitals (greater than 200 beds) that were distributed geographically across the United States. Results indicated that nutrition support dietitians had a more positive view of how their profession was viewed by others than did general clinical dietitians. A larger proportion of nutrition support dietitians than of general clinical dietitians believed that they were viewed as working with specialized patients (14% vs. 9%), as an important part of the hospital team (20% vs. 6%), and as acting as a resource person for the medical staff (30% vs. 13%). Physicians and chief dietitians held the strongest opinions concerning the image of the nutrition support and general clinical dietitians; both held a more positive view of the nutrition support dietitian. A greater number of physicians expressed the view that nutrition support dietitians were more competent and knowledgeable than were general clinical dietitians (24% vs. 9%) and were an important part of the hospital team (36% vs. 15%). A greater percentage of chief dietitians said that nutrition support dietitians, in comparison with general clinical dietitians, were competent and knowledgeable (40% vs. 19%) and professional, well respected, expert, and more specialized (65% vs. 44%). In comparison with 5 years ago, 76% and 69% of nutrition support and general clinical dietitians, respectively, thought that they are now viewed as more professional and as having abilities that are recognized.

Attitude of Health Personnel↗
PubMed1988

The role of the clinical dietitian: II. Staffing patterns and job functions.

On the basis of responses to a telephone questionnaire, this study evaluated--from the viewpoint of nutrition support dietitians, general clinical dietitians (dietitians who are not members of a nutrition support team and who provide general clinical dietetic services), and other health professionals--the current job functions that nutrition support and general clinical dietitians perform in hospitals. Anticipated staffing needs and desired job functions were also assessed. For the nutrition support and general clinical dietitians, as viewed by themselves and other health professionals, there was considerable overlap in many job activities. However, a significantly larger proportion of directors of nursing thought that nutrition support dietitians were more involved than general clinical dietitians in the evaluation of nutritional status (42% vs. 14%) and in contributing expertise to medical team discussions (48% vs. 12%). A significantly larger proportion of physicians viewed the nutrition support dietitian as more involved than the general clinical dietitian in in-service programs for medical and nursing staffs (32% vs. 6%). A large proportion of directors of nursing (62%), hospital administrators (34%), and physicians (56%) believed that dietetic involvement in the supervision of food preparation, especially by general clinical dietitians, was much greater than did the dietetic staff. The outlook for the future suggests a greater participation by both the nutrition support and the general clinical dietitian in direct patient care functions and less involvement in food preparation and clerical tasks.

Dietetics↗
PubMed1987

Physical growth of infants 7 to 13 months of age: results from a national survey.

This study considers measurements of weight, recumbent length, head circumference, triceps skinfold, and arm circumference of 1,100 infants aged 7 to 13 months from a cross-sectional sample representative of the U.S. infant population. Based on these data, smoothed percentiles of weight, recumbent length, head circumference, triceps skinfold, and arm circumference by sex and age (in months) and weight for recumbent length were calculated. Compared with the percentile values from the National Center for Health Statistics (NCHS; Hamill et al., 1977, DHEW Publ. No. PHS 78-1650), percentile values from the 1984 Ross Laboratories Infant Nutrition Survey (RNS) for weight, recumbent length, and weight for recumbent length tended to be smaller (p less than .05). We attribute these variations to differences in sampling design and conclude that they are not of sufficient magnitude to warrant new growth charts. Smoothed percentiles for triceps skinfold and arm circumference presented herein are new reference values that can be used for assessment of the nutritional and growth status of older infants.

Anthropometry↗
PubMed1987

Feeding low-fat milk during infancy.

Despite the widespread agreement that low-fat milk should not be used during infancy, there is a sizable portion of infants in the United States who were fed a diet that included low-fat milk (less than or equal to 2% fat). In 1985, 14% of infants 8 months old, 20% of infants 10 months old, and 32% of infants 12 months old were fed low-fat milk. The reasons given most often by mothers for low-fat milk use was their consideration that low-fat milk has less fat than whole cow's milk and that low-fat milk use was recommended/suggested by their physician. Nutrient intakes of infants fed low-fat milk are compared to those of infants fed whole cow's milk and infant formula. Except for fat, nutrient intakes of infants fed low-fat milk or whole cow's milk were similar. A majority of infants fed either low-fat milk or whole cow's milk received amounts of sodium, potassium, and chloride that exceeded the recommended safe and adequate ranges and amounts of iron below the RDA. These data are considered in relation to dietary requirements during infancy.

Animals↗
PubMed1985

Nutrient intakes of American infants and children fed cow's milk or infant formula.

Between April 1984 and August 1984, a national survey, the Ross Laboratories Infant Nutrition Survey, was undertaken to assess patterns of food consumption of American infants ranging in age from 6.5 months to 13.4 months. Nutrient intakes of 865 infants were evaluated according to different foods (milk and milk products, non-iron-fortified formula, iron-fortified formula, infant cereal, commercial baby foods, and home-prepared table foods). Results indicated that most American infants consumed nutrients in appropriate amounts. However, a large proportion of infants who were fed a diet that included cow's milk received amounts of sodium, potassium, and chloride that exceeded the recommended safe and adequate ranges. The median intake of iron of infants fed either cow's milk or a non-iron-fortified formula was below the recommended dietary allowance; a low percentage of these infants received medicinal iron supplementation. The results also indicated that the median estimated renal solute load of the diet of infants fed cow's milk was approximately twice the amount of that of infants fed formula. These data may be useful in the development of nutritional programs for older infants.

Animals↗