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K S Steinbeck

Publications and source records attributed to K S Steinbeck.

At least 19 recordsLinked to original sources
PubMed2006

A proposed protocol for the development of a register of trials of weight management of childhood overweight and obesity.

INTRODUCTION: Currently, there is no international co-ordinated approach to research into childhood obesity. This is despite much research activity in this area and the universality of the condition. METHOD: This proposal involves the development of an international register of randomized controlled trials of weight management in overweight and obese children. The primary purpose of the register will be to generate and perform important, focussed prospective meta-analysis of data from trials using the conventional weight management strategies. Prospective meta-analysis is an emerging methodology and has some methodological advantages over retrospective meta-analysis. PROPOSAL: The fundamental initial tasks will be to create scientific interest in the proposal, to identify and co-ordinate Management and Advisory Committees with international membership, to determine and define inclusion and exclusion criteria for trial registration, to define the questions that need to be addressed by prospective meta-analysis and finally to engage investigators to register.

Child↗
PubMed2006

Comparison of metabolic syndrome prevalence using six different definitions in overweight pre-pubertal children enrolled in a weight management study.

OBJECTIVES: To assess the implications of variation in Metabolic Syndrome (MS) definition (biochemical and anthropometric indicators) on MS prevalence estimates in a population of overweight and mildly obese children. DESIGN: Cross-sectional study. SUBJECTS: Ninety-nine (64 girls) overweight or mildly obese, but otherwise healthy, pre-pubertal 6-9-year olds recruited for a randomized controlled trial of weight management. MEASURES: Height, weight and waist circumference were measured with BMI and waist z-scores calculated. Fasting cholesterol and fractions, glucose and insulin were measured, together with systolic and diastolic blood pressure (BP). Anthropometric and metabolic indicators were classified as normal or elevated using adult- or child-specific cut points with clustering of MS indicators also assessed using two adult and three child-specific definitions. RESULTS: A total of 0-4% of subjects were classified with MS when adult definitions were applied. This increased to between 39 and 60% using child-specific definitions, varying according to whether hyperinsulinaemia was central to the MS classification. Systolic BP, triglycerides, total cholesterol, high-density lipoprotein cholesterol and waist z-score increased across insulin quartiles (P<0.05). The use of body mass index and waist circumference in the MS definition classified the same subjects. CONCLUSIONS: The classification of MS in children depends strongly on the definition chosen, with MS prevalence estimates higher if insulin is part of the definition and child-specific cut points for metabolic indicators are used. Hyperinsulinaemia and MS are common consequences of childhood obesity but they are not commonly part of the assessment or management plan for weight management in children. There is a need for the establishment of normal insulin ranges and consistent definition of MS in childhood and adolescence.

Age Factors↗
PubMed2003

Food, activity and family--environmental vs biochemical predictors of weight gain in children.

OBJECTIVE: To identify whether measures of energy intake and expenditure predict excessive weight gain over time in children and to describe how these measures relate to similar measures in parents. DESIGN: Prospective, descriptive study over 12 months with no intervention. SETTING: University teaching hospital. SUBJECTS: Children aged between 6.0 and 9.0 y. Recruitment was through advertisement. A total of 59 children (30 F), 41 mothers and 29 fathers. In all, 41 (69%) of the children were reviewed at 12 months (20 F). RESULTS: No significant correlations were identified between body mass index (BMI) z-score change in children over 12 months for any dietary variable or for any measures of energy expenditure, including hours of television viewing or percent time spent in low-, moderate- or high-intensity activity. The BMI z-score change over 12 months was significantly correlated with LDL cholesterol and Apo B/ApoA-1 ratio, independent of percent body fat (r=0.45, P=0.01; r=0.37, P=0.03). A significant positive correlation was found for mothers and girls for percent time in moderate to high activity (r=0.44, P=0.03) and between fathers and children for percent time spent in low activity (r=0.43, P=0.005). CONCLUSIONS: The study has been unable to identify environmental predictors that indicate propensity to faster weight gain over time in this cohort of children, but has extended the evidence on lifestyle-influenced biochemical predictors that do. An overall lack of vigorous activity in this age group, and correlations between parental and child activity and inactivity have been identified.

Adult↗
PubMed2001

Self-efficacy in relation to eating behaviour among obese and non-obese women.

OBJECTIVE: To assess the effect of a 3 month behaviour modification weight management programme on self-efficacy and anthropometric variables among obese women seeking treatment at an obesity management clinic and to compare self-efficacy among these obese women to non-obese women. DESIGN: Cross sectional. SUBJECTS: A total of 161 non-obese (BMI 22.6+/-2.9 kg/m(2)) and 138 obese (BMI 37.7+/-5.8 kg/m(2)) women of similar age. MEASUREMENTS: Self-efficacy in relation to eating was assessed by the Weight Efficacy Lifestyle (WEL) questionnaire. Demographic information was obtained by interview and questionnaire in the obese and by questionnaire in the non-obese. Anthropometric measurements were obtained by direct measure in the obese and BMI was calculated from self-reported weight and height in the non-obese. RESULTS: At entry to the programme obese women scored significantly less (P<0.0001) than non-obese women on the WEL (99.4+/-34.1 vs 139.0+/-24.9). Women who completed the programme (n=65) demonstrated a decrease in waist circumference of 3.9+/-5.3 cm, a 10.0+/-11.5% loss of excess weight and a significant improvement in total WEL score from 106.0+/-30.3 to 126.5+/-28.4. CONCLUSION: Improvements in some dimensions of self-efficacy among obese women were of sufficient magnitude to attain scores similar to women of a normal weight. The WEL questionnaire may provide an additional measure of success as well as provide positive feedback and encouragement to the client.

Adolescent↗
PubMed2001

Low-density lipoprotein subclasses in children under 10 years of age.

OBJECTIVE: To examine the prevalence of small dense low density lipoprotein (LDL) in a cohort of children under 10 years of age and to investigate the relationship to other biochemical variables and to measures of fatness. A preponderance of small dense LDL (pattern B), is associated with obesity, abdominal fat accumulation, insulin resistance and risk of heart disease in adults. METHODOLOGY: LDL peak particle diameter (PPD) was determined by gel electrophoresis in 53 children under 10 years of age and in 65 of their parents: apoproteins A1 and B were determined by turbidimetry. Anthropometric variables, basic lipid profiles, insulin and leptin had been determined previously. Differences between patterns A (large light particles > 25.5 nm diameter) and B were examined by t-test, Chi-square, or Mann-Whitney test. Relationships between the variables were reported as Pearson correlation coefficients. RESULTS: Pattern B (PPD of < or = 25.5 nm) prevalence was 7.5% in children and 11% in parents (17% in men and 5% in women). Most of the children (86%) who had PPD < or = 26.0 nm also had parents with PPD in this range. A strong association was found between children's and mother's PPD (r=0.60, P < 0.001), but this was somewhat less with fathers (r=0.40, P=0.02). Children in the lowest tertile of PPD had a tendency towards a higher body mass index, waist, fat mass and insulin. CONCLUSIONS: The prevalence of small dense LDL is lower in children under 10 years of age than in their parents; fathers had a higher prevalence of pattern B than mothers and there is some evidence of a familial effect in the inheritance of pattern B.

Age Distribution↗
PubMed2001

The importance of physical activity in the prevention of overweight and obesity in childhood: a review and an opinion.

The prevalence of childhood obesity is increasing and there are a number of theoretical reasons as to why intervention may be more effective in childhood. There are certain risk times for the development of obesity in childhood, which provide a basis for targeted intervention. In addition, tracking data supports the persistence of obesity, at least in later childhood, as well as cardiovascular risk factors. Physical activity is the discretionary component of energy expenditure and there is evidence that falling levels of physical activity are contributing to the obesity epidemic. Physical activity in children is related to developmental stage, is reduced with increasing age and is influenced by parental physical activity. While there is debate about the immediate health benefits of physical activity to children, there are data to support that lower physical activity levels and sedentary behaviours are associated with a higher prevalence of obesity in children. Physical activity is an accepted strategy in the treatment of established obesity (tertiary prevention). The role of physical activity in the prevention of obesity (primary and secondary prevention) is less clear. However a number of recent school-based interventions directed at either increasing physical activity and/or decreasing sedentary behaviours, have shown encouraging results. On balance, increasing physical activity in children is an attractive and non-restrictive approach to obesity prevention. To adopt this approach requires the support and involvement of many community sectors other than health.

Adolescent↗
PubMed2001

Total energy expenditure, body fatness, and physical activity in children aged 6-9 y.

BACKGROUND: The recent worldwide increase in the prevalence of childhood obesity may be due in part to a decrease in children's physical activity levels. OBJECTIVE: The current study of children in the years just before puberty aimed to 1) measure total energy expenditure (TEE) by use of the doubly labeled water (DLW) method, 2) determine the proportion of TEE related to physical activity, 3) investigate the relations between measures of physical activity and body fatness, and 4) investigate possible sex differences in these relations. DESIGN: The DLW technique was used to measure TEE over 10 d in 106 healthy children (52 boys) aged 7.8 +/- 0.9 y (x +/- SD). Fat-free mass, and hence fat mass, was derived from the (18)O dilution space. Resting energy expenditure (REE) was calculated with use of the Schofield equations. Physical activity level was calculated as TEE/REE. RESULTS: Mean TEE in both boys (7871 +/- 1135 kJ/d) and girls (7512 +/- 1195 kJ/d) was significantly different (P < 0.0001) from FAO/WHO/UNU recommendations (13% and 9% lower, respectively). There was no significant difference in physical activity level between boys (1.69 +/- 0.22) and girls (1.71 +/- 0.23). In boys but not girls, physical activity level was inversely correlated with BMI (r = -0.37, P < 0.01), fat mass (r = -0.46, P < 0.005), and percentage of body fat (r = -0.50, P < 0.0001). CONCLUSIONS: In boys but not girls, percentage of body fat is inversely associated with physical activity level. Physical activity is one factor contributing to body fatness in boys, but additional factors may influence the size of the fat stores in girls.

Adipose Tissue↗
PubMed2001

Comparison of total energy expenditure and energy intake in children aged 6-9 y.

BACKGROUND: The accurate measurement of food intake in children is important for assessing nutritional status. OBJECTIVE: We sought to both compare measurements of energy intake (EI) from diet records and of total energy expenditure (TEE) by the doubly labeled water (DLW) method and to investigate misreporting of EI. DESIGN: Forty-seven children (22 boys and 25 girls) aged 7.4 +/- 0.8 y ( +/- SD) were recruited from 25 schools in western Sydney. TEE was measured by DLW over 10 d and EI by use of 3-d food records. Misreporting was defined as [(EI - TEE)/TEE] x 100%. RESULTS: Girls had a higher (P = 0.02) percentage of body fat (28.2 +/- 7.0%) than did boys (22.9 +/- 8.0%); otherwise there were no differences among sex. Although mean (+/-SD) values for EI (7514 +/- 1260 kJ/d) and TEE (7396 +/- 1281 kJ/d) were not significantly different, there was no significant correlation between EI and TEE. EI and TEE were 9% and 11% lower, respectively, than current World Health Organization recommendations for EI. The relative bias (mean difference, EI - TEE) was low at 118 kJ/d, but the limits of agreement (bias +/- 2 SD of the difference) were wide at 118 +/- 3345 kJ/d. Although the mean percentage of misreporting was low (4 +/- 23%), the high SD indicates large intraindividual differences between EI and TEE. The most significant predictor of misreporting was dietary fat intake (r(2) = 0.45, P < 0.0001). Misreporting was not associated with sex or body composition. CONCLUSIONS: In this age group, reported EI is not representative of TEE at the individual level. However, at the population level, 3-d food records may be used for surveys of EI by 6-9-y-old children.

Anthropometry↗
PubMed1999

Coronary heart disease risk factors in male adolescents, with particular reference to smoking and blood lipids.

PURPOSE: To examine coronary heart disease (CHD) risk factors, particularly blood lipids and smoking, in adolescent boys in the Sydney Metropolitan area, and to investigate possible differences between boys from English-speaking (ESB) and non-English-speaking backgrounds (NESBs). METHODS: Male volunteers aged 15-18 years were recruited from the senior years of four secondary schools in different geographical areas of Sydney. Body mass index (BMI), waist-hip ratio (WHR), blood lipids, and percent body fat were measured. Behavioral variables were estimated by questionnaire. RESULTS: A total of 110 boys were recruited; 74% were from an ESB. Mean WHR (0.836 +/- 0.045), waist circumference (80.6 +/- 9.4 cm), and percent body fat (21.0 +/- 6.3) were similar across age groups. Atherogenicity of the lipid profile, as measured by the ratio of total cholesterol to high-density lipoprotein cholesterol (TC:HDL-C), was lower in boys aged 15 years than in any other age group (p < .05). TC:HDL-C was strongly associated with BMI (r = .57; p < .0001) and WHR (r = .35; p < .01). Smokers had higher BMI, were less active and had lower HDL-C (p < .001) and higher TC:HDL-C (p < .0001) than nonsmokers. Smoking, even of short duration, and quite moderate consumption of cigarettes (6/day) were associated with a deterioration of the lipid profile. Boys from NESBs had a higher degree of risk in all of the factors examined. CONCLUSIONS: Regular smoking of short duration has an appreciable impact on lipid and lipoprotein concentrations in this sample of Australian adolescent boys. Boys from an NESB appear to be at greater risk of developing CHD in later life.

Adolescent↗
PubMed1997

Very low calorie diet (VLCD): a useful alternative in the treatment of the obese NIDDM patient.

Conventional treatment of obese noninsulin dependent diabetes mellitus (NIDDM) patients is often unsatisfactory. In this study the efficacy of Modifast, a commercial very low calorie diet (VLCD), was evaluated in a population of obese poorly controlled NIDDM patients. The mechanisms of action of VLCD in these patients were also studied by comparing: (i) Plasma insulin and glucose profiles after a VLCD and an isocaloric mixed meal and (ii) plasma amino acid levels, both at baseline and after four weeks of VLCD treatment. A total of 14 obese NIDDM patients (M/F 7/7. median body mass index (BMI) 38.7 kg-2, interquartile range (IQ) 34.7-46.5 kg-2, waist circumference 116 cm, IQ 106-139 cm, insulin treated 7/14) with poor diabetic control (HbA1c 8.6%, IQ 7.8-10%) were studied. Patients were given a VLCD (425 kcal/day) for 12 weeks. At baseline, VLCD and isocaloric meal tests were performed on consecutive mornings. Fasting plasma amino acid levels were also determined at baseline and after 4 weeks of VLCD treatment. Weight, waist circumference, HbA1c, blood pressure, fasting plasma insulin, total cholesterol and triglyceride levels all fell significantly following VLCD treatment. Insulin therapy was able to be ceased in the seven insulin treated patients. Oral hypoglycaemic agent dosage fell from a median of eight (IQ 6-12) to two (IQ 0-8) tablets per day (P = 0.03) in patients initially on this form of therapy. Insulin secretion was higher after VLCD than isocaloric meal (P = 0.04). Fasting plasma alanine level fell from 512.0 (IQ 412.0-563.0) to 374.0 (IQ 342-472.0) mumol/l (P = 0.04) following VLCD treatment. In conclusion, the short term use of a VLCD is very effective in rapidly improving glycaemic control and promoting substantial weight loss in obese NIDDM patients. Moreover, a VLCD diet increases insulin secretion and reduces substrate for gluconeogenesis. Thus, VLCD treatment may improve glycaemic control by factors more than caloric restriction alone.

Adult↗
PubMed1997

Chronic illness perception in adolescence: implications for the doctor-patient relationship.

OBJECTIVE: To describe the inter-relationship of chronic illness severity as perceived by adolescents with both psychosocial well-being and objective measures of illness severity. Additionally to compared the adolescents' perception of illness severity with how their physicians believe that the adolescents perceive their illness severity. METHODS: The psychological well-being of 48 adolescents with either cystic fibrosis (CF) or insulin-dependent diabetes mellitus (IDDM) was measured by four standardized questionnaires. The adolescents' perception of severity of illness was measured using an original instrument (PSCI), and this measure was compared to their physicians' estimates of how the adolescents perceived the severity of their illness and clinical illness. RESULTS: There were 24 patients in both the CF and IDDM groups. Both groups were found to function well psychosocially; although, there were more patients with low self image compared to normative values. Depression and low self image were associated with a greater adolescent perception of illness severity. For both chronic illness groups, physicians' assessment of assumed adolescent perception of disease severity correlated with clinical indices of disease severity and was higher than the perception of illness severity reported by the adolescents. For adolescents with CF, but not with IDDM, perception of severity of chronic illness correlated with clinical indices. CONCLUSIONS: For adolescents with chronic illness, their perception of illness severity is an important indicator of psychosocial well-being. Physicians do not accurately infer their patients' perception of illness severity.

Adaptation, Psychological↗
PubMed1996

A shared care approach in obesity management: the general practitioner and a hospital based service.

OBJECTIVE: To describe the process of establishing a Shared Care obesity management programme between general practitioners and a hospital based specialist obesity service and to compare outcomes of the Shared Care programme (SC) to an established hospital based programme (MOS). DESIGN: A comparative study of two obesity management programmes. Patients were matched on gender, age and BMI (kg/m2). SUBJECTS: 29 female and eight male (age: 47.0 +/- 2 years, BMI 35.9 +/- 0.8 kg/m2) patients enrolled in the Shared Care programme (SC) were matched to 81 female and 20 male (age: 45.8 +/- 1.1 years, BMI 35.7 +/- 0.4 kg/m2) patients enrolled in a hospital based programme (MOS). MAIN OUTCOME MEASURES: Relative and absolute weight loss and retention rate were compared between the programmes at 10 and 26 weeks. Food habits were assessed at enrolment and week 10 of the programme in the SC group by a Food Habits Questionnaire and cognitive restraint, disinhibition and hunger were assessed by the Eating Inventory Questionnaire. RESULTS: Shared Care patients (n = 28) lost significantly more weight than the MOS patients (n = 60) (SC 4.8 +/- 0.6 kg and MOS 2.6 +/- 0.4 kg; p = 0.0016) over the 10 weeks of the programme. At 26 weeks both groups demonstrated a 5 kg weight loss. There was a significant improvement in food habits, and cognitive restraint, disinhibition and hunger over the 10 weeks of the programme in the SC group. Patient satisfaction was reflected in a better retention rate at 26 weeks by the Shared Care group. CONCLUSION: The study demonstrated that the obese patient managed in a shared care setting achieved better weight loss in the short term and attrition was lower in the longer term than a similar patient attending a specialist service based in a hospital.

Adult↗
PubMed1995

Dexfenfluramine treatment of obesity: a double blind trial with post trial follow up.

OBJECTIVE: As successful weight management demands a long term approach, a better understanding of weight changes during and for significant periods after cessation of dexfenfluramine therapy is essential to the evaluation of the drug's effectiveness in clinical practice. This study aimed to investigate additional benefits to weight loss during 6 months treatment with dexfenfluramine in 60 patients enrolled in a weight loss programme. DESIGN: Sixty obese subjects (21 males; 39 females) were randomised to dexfenfluramine (15 mg twice daily) or placebo for six months. Fifty one (27 dexfenfluramine; 24 placebo) subjects completed the double blind, randomised, placebo controlled clinical trial. RESULTS: After a one month 'run in' phase and six months treatment, weight loss in the dexfenfluramine group was significantly greater than placebo, 9.7 +/- 1.1 kg vs 4.9 +/- 0.9 kg (mean +/- s.e.m.); P = 0.002. Reduction in body fat, 5.0 +/- 0.7 kg vs 1.0 +/- 0.9 kg; P = 0.002 and waist circumference, 10.5 +/- 1.9 cm vs 5.7 +/- 1.1 cm; P = 0.04 was also greater in the dexfenfluramine group. Despite significant weight loss, waist to hip ratio (WHR) did not change in either group. The dexfenfluramine group reported a significantly greater incidence of nausea, dry mouth and dizziness which tended to decrease as treatment progressed. No subjects withdrew due to drug induced side effects. Reduction in serum triglyceride levels and an increase in HDL cholesterol (in female subjects) in conjunction with a reduction in fasting insulin, collectively support an improved cardiovascular risk profile in the dexfenfluramine group. Despite significant weight loss, these risk factor measurements worsened in the placebo group. After cessation of dexfenfluramine therapy, there was a significantly greater weight regain indicating a loss of treatment effect. By 5 months after cessation of dexfenfluramine, the treatment effect was negated with weight loss in the dexfenfluramine (6.0 +/- 1.6 kg) and placebo (6.2 +/- 1.3 kg) group, similar. CONCLUSION: The results of this study support the longer term use of dexfenfluramine therapy for patients with chronic obesity.

Adolescent↗
PubMed1994

Tissue [1-14C] 2-deoxyglucose metabolism in the gold thioglucose obese mouse: effects of 'dieting'.

Glucose uptake into heart and skeletal muscle and white and brown adipose tissue is reduced in mice with gold thioglucose-induced obesity. After acute dieting (40% of lean control uptake) for 18 days, glucose uptake into tissues remains low despite consistently elevated serum insulin levels. This reduced glucose uptake may be a consequence of the raised serum fatty acid levels produced by dieting. When the reduced weight obese mice are pair-fed with lean controls, they gain weight. Glucose uptake into both muscle and adipose tissues is markedly increased, and the insulin resistance of both previous obesity and recent relative starvation is rapidly overcome at the level of the glucose uptake, but serum insulin levels and insulin secretion from islets of Langerhans isolated from these animals remain high. To maintain reduced weight, previously obese animals were fed 80% of lean control intake. In this situation, glucose uptake into the four tissues studied remained reduced (compared to lean controls), consistent with relative starvation. While tissue glucose uptake increases after dieting and re-feeding of obese animals, serum insulin levels remain high, indicating persistence of a degree of insulin resistance. Reduced-weight obese animals are energy-efficient in that they gain excess weight on the control intake.

Adipose Tissue↗
PubMed1994

The prevalence of obstructive sleep apnoea in an obese female population.

Obstructive sleep apnoea (OSA) has been estimated to affect between 1 and 4% of the total population. OSA may be more frequent among women than studies based on subjects presenting for treatment would indicate. The aim of this study was to determine the prevalence of OSA in an obese female population (BMI > 30 kg/m2, age > 18 years) who presented to a hospital-based obesity clinic. The women were screened by an overnight ambulatory sleep study (MESAM) to detect OSA. Subjective sleep quality and sleep disturbance were assessed by a 19-item questionnaire, the Pittsburg sleep quality index (PSQI). From a population of 108 women, 29 were screened by MESAM. OSA was determined on the basis of respiratory disturbance index (RDI). The prevalence of OSA, defined as five or more respiratory disturbances per hour, was 37.9%. The mean age of the women was 43.6 +/- 2.57 years (mean +/- s.e.m.) and they had a mean BMI of 40.7 +/- 1.40 kg/m2. There was a significant positive correlation for RDI and BMI (r = 0.71; P < 0.001). Our findings indicate that over one third of women had OSA, yet they did not complain of symptoms even though the PSQI questionnaire indicated that they were poor sleepers. Non-specific symptomatology of OSA may be important diagnostically, particularly in women, and obese women should be considered at risk of OSA.

Adult↗
PubMed1992

Severe obesity: the use of very low energy diets or standard kilojoule restriction diets.

OBJECTIVES: To determine the efficacy of two dietary therapies in both the short term (hospitalisation) and the longer term treatment of severe obesity. DESIGN: A descriptive study of two patient groups with obesity defined by a body mass index of greater than 30 kg/m2. SETTING: A multidisciplinary weight control program in a tertiary care hospital. PATIENTS: All admissions to hospital of patients on the weight control program for initiation of weight loss during a period of 48 months. INTERVENTION: A standard kilojoule reduction regimen or the use of complete, followed by partial, long term meal substitution with a very low energy liquid diet (VLED), coupled with an exercise and a behavioural modification program. OUTCOME MEASURES: Weight loss during and after hospitalisation was measured in both dietary regimen groups. RESULTS: Both diets induced weight loss in hospital. Men prescribed VLED lost significantly more weight, 8.3 +/- 0.8 kg (mean +/- SEM) than women prescribed this diet (5.5 +/- 0.5 kg) or standard kilojoule restriction (5.1 +/- 0.8 kg). CONCLUSIONS: VLED and standard kilojoule restriction are both effective for the treatment of severe obesity, particularly in a controlled environment (hospitalisation). In the longer term, VLED is an effective method of maintaining weight loss. Lack of continuing weight loss may reflect the patients who were initially placed on this regimen--small eaters with a presumed high metabolic efficiency.

Adult↗