Life expectancy as a summary of mortality in a population: statistical considerations and suitability for use by health authorities.

OBJECTIVE: To investigate the sampling distribution and usefulness of expectation of life in comparisons of mortality at health district level or below. DESIGN: Derivation of a formula for the variance of the expectation of life, confirmation of the result and generation of the sampling distribution by Monte Carlo simulation; comparison of expectation of life with standardised mortality ratio (SMR) and other summary indices of mortality. SETTING: A health district in Trent Region, England. SUBJECTS: Routinely available mortality statistics at electoral ward level and above. MAIN RESULTS: Given reasonable and simple assumptions the sampling distribution of the expectation of life is approximately normal. Expectation of life shows a high negative correlation with SMR even if the oldest age band for the SMR is open ended. CONCLUSIONS: Where sampling error is an issue, inference concerning differences in mortality rates between populations can be based on expectation of life, which is better for illustrative purposes than SMR. The formula for the variance of the expectation of life is more complex however. If the final age band is open ended, its lower bound should be as high as possible to avoid misleading results caused by hidden differences in age structure.

Intratumoral chemotherapy with fluorouracil/epinephrine injectable gel: a nonsurgical treatment of cutaneous squamous cell carcinoma.

BACKGROUND: We attempted to originate a nonsurgical treatment alternative for cutaneous squamous cell carcinoma (SCC), and we evaluated intratumoral modified-release chemotherapy with fluorouracil/epinephrine injectable gel (5-FU/epi gel). OBJECTIVE: To assess the safety and efficacy, we conducted an open-label pilot study of 5-FU/epi gel in 25 patients with biopsy-proven SCC lesions on the face, head, neck, trunk, arms, and hands. METHODS: Each tumor site was injected intradermally with up to 1.0 ml of 5-FU/epi gel. One SCC per patient was treated weekly for up to 6 weeks, then observed for 4 months at which time the tumor site and margins were excised for histologic examination. RESULTS: Overall, 96% (22 of 23) of evaluable treated tumors had histologically confirmed complete tumor clearing. No clinically significant systemic reactions or unexplained treatment-related adverse medical events occurred. The evaluations of the cosmetic appearance of the treated sites, judged subjectively by clinicians and patients, were mostly good to excellent and generally in close agreement. CONCLUSION: Treatment of superficial SCC with 5-FU/epi injectable gel results in a high rate of histologically confirmed complete tumor responses and may provide a nonsurgical treatment alternative in selected patients.

A controlled evaluation of a fitness and nutrition intervention program on cardiovascular health in 10- to 12-year-old children.

BACKGROUND: Programs to improve cardiovascular health in schoolchildren need careful scientific evaluation. METHOD: In a randomized controlled trial of nutrition and fitness programs over a period of about 9 months, 1,147 10- to 12-year-olds from 30 schools were allocated to one of five health programs: fitness, fitness + school nutrition, school-based nutrition, school + home nutrition, home-based nutrition, or a control group. Nutrient intake, fitness, anthropometry, blood pressure, and blood cholesterol were measured before and after intervention. RESULTS: Fitness increased and diastolic blood pressure and triceps skinfolds decreased significantly for girls in the fitness groups. Baseline consumption of sugar, fat, and fiber was outside national guidelines; blood cholesterol exceeded recommendations in one-third of children. In girls, fat intake decreased significantly in the two home nutrition groups and fiber intake increased in the school + home nutrition and fitness groups. Boys in the fitness, fitness + school nutrition, and school + home nutrition group reduced sugar intake. Change in sugar intake correlated negatively with change in fat intake in both boys and girls. CONCLUSIONS: Teacher-implemented health packages are feasible with minimal training but programs should differ between boys and girls. Fitness programs were more successful than nutrition education particularly in girls. Clearer nutrition messages should prevent reciprocal changes in sugar and fat. For girls, the 3 mm Hg reduction of diastolic blood pressure, less obesity, and increased fitness could translate into a substantial reduction in cardiovascular risk in adult life.

Blood pressure and body composition in children: importance of allowing for cuff size.

A cross-sectional study of blood pressure (BP) was conducted in a sample of 1312 Australian school children aged 11-12 yrs. In line with current recommendations for the measurement of BP, a cuff of appropriate size was chosen for each subject based on his or her arm circumference. Analyses revealed statistically significant independent relationships between measured BP and cuff size. Observed relationships in the sample between measured BP and body composition variables were substantially affected when BP measurements were adjusted to remove the effect of cuff size. Cuff-associated biases in estimates of relationships between BP and body composition variables may still exist even though cuffs are carefully chosen to suit arms of different circumferences. It would appear that this potential problem is largely unrecognised. Some previous studies of relationships between BP and body composition may have been affected.

Relationships between blood pressure and measures of dietary energy intake, physical fitness, and physical activity in Australian children aged 11-12 years.

STUDY OBJECTIVE: The aim was to examine associations between blood pressure and dietary energy intake, physical activity, and physical fitness in Australian children. DESIGN: The study was a survey of year 7 children attending schools in metropolitan Perth. SETTING: Survey schools were located in suburbs representative of the range of socioeconomic strata in metropolitan Perth. PARTICIPANTS: Data were obtained on 1311 out of 2045 eligible children (64%). The sample included 681 boys and 630 girls. Mean age was 12.0 (SD 0.4) years. MEASUREMENTS AND MAIN RESULTS: Triplicate blood pressure measurements were obtained using a Dinamap oscillometric recorder. Dietary energy intakes were computed from two week day 24 h records. Physical activity was assessed using questionnaires. Physical fitness was measured using a shuttle run test. Additional measurements included weight, height, and skinfold thickness at four sites. A previous observation of an inverse relationship between diastolic blood pressure and dietary energy intake in boys was confirmed. There was evidence of an inverse relationship in girls but not in boys between blood pressure and physical activity. There was little evidence of relationships between blood pressure and physical fitness. CONCLUSIONS: Compared with weight and body mass index, dietary energy intake and the chosen measures of physical activity and physical fitness are poor predictors of blood pressure in the population studied.

Clinical experience with the second metatarsal artery neurovascular flap.

Three cases of innervated web space flaps from the foot based on the second metatarsal artery and the second common digital nerve are described. This flap provides glabrous skin for digital reconstruction with good sensory recovery and minimal donor site morbidity.

Reflotron cholesterol measurements in 1112 Australian children aged 10-12 years.

OBJECTIVE: To study the distribution of blood cholesterol concentration in a sample of Western Australian schoolchildren. DESIGN: The Reflotron dry-chemistry system (Boehringer Mannheim, Germany) was used to measure cholesterol in finger-prick blood samples obtained from Year 6 children aged 10-12 years attending government schools in metropolitan Perth. Recruitment methods ensured that children from different socioeconomic strata were represented. PARTICIPANTS: For the 1239 children enrolled in Year 6 in 30 government schools, parental consent to participate was obtained for 1144; of these cholesterol concentration was measured in 1112. RESULTS: The measurement method proved practicable and was generally well accepted. Cholesterol levels were somewhat lower than those obtained using a laboratory reference method and a bias, relative to national quality assurance standards, was estimated to be -0.32 mmol/L. Mean cholesterol level in boys (4.28 mmol/L, SD 0.69) was not significantly different from that in girls (4.35 mmol/L, SD 0.72). Allowing for measurement bias, 52% of boys and 57% of girls had cholesterol levels exceeding the National Heart Foundation's designated "desirable" level of 4.5 mmol/L for children. CONCLUSIONS: The distribution of cholesterol levels in Australian children compares unfavourably with distributions in children in countries with low rates of cardiovascular disease and indicates a need for widespread, appropriate diet and lifestyle changes.

Urinary catecholamines, plasma insulin and environmental factors in relation to body fat distribution.

The relationship of body fat distribution to insulin and the catecholamines, hormones that affect lipolysis differentially by fat site, was examined within an environmental context, including factors of medication use, physical activity, dietary intake, educational attainment, and age. Four cross-sectional body fat areas (cm2) were determined by three computed tomography (CT) scans (subcutaneous chest fat at the level of the nipples, subcutaneous and intra-abdominal fat at the level of the umbilicus, and subcutaneous left mid-thigh fat) in 191 second-generation Japanese-American men aged 45-74 years. The site-specific fat measurements were first examined in relation to use of beta-adrenergic antagonists, then to fasting plasma insulin and C-peptide levels and to urinary epinephrine and norepinephrine levels from a 24-h urine collection made during usual daily activities. Greater fat stores in the intra-abdominal area, even after adjustment for body mass index (BMI, weight/height2) and presence of coronary heart disease, were found to be related to use of beta-adrenergic antagonists. In men taking no adrenergic antagonists (n = 157), after adjustment for BMI, truncal fat measurements of the chest (partial r = -0.16, P less than 0.05) and intra-abdominal area (partial r = -0.21, P less than 0.05) were found to be inversely related to epinephrine, and intra-abdominal fat (partial r = 0.25, P less than 0.01) alone was directly related to fasting plasma insulin. With respect to other environmental variables, the significant inverse relationship of intra-abdominal fat (adjusted for BMI) with physical activity (partial r = -0.17, P less than 0.05) and the significant difference in intra-abdominal fat by educational attainment (college 102.3 +/- 5.7 vs no college 115.7 +/- 6.1 cm2, P = 0.03) became non-significant with adjustment, using multiple regression analysis, for insulin in the case of physical activity and epinephrine in the case of educational attainment. Thus, intra-abdominal fat showed a unique set of relationships to metabolic parameters which could be further related to certain environmental variables.

A comparison of methods of dietary assessment in Australian children aged 11-12 years.

A total of 225 children attending year 7 classes in state primary schools in Perth, Australia, participated in the study. Nutrient intakes were determined by a number of low-intensity methods and compared with intakes determined by a reference method based on 14 24-h diet records collected over several months and covering each day of the week twice. The low-intensity methods were (i) a food frequency questionnaire (FFQ) administered to the children in school, (ii) the same FFQ administered to the children's parents by post and (iii) a small number (one, two or three) of 24-h diet records completed by the children. The FFQ included 175 food items, the time frame was 'during the previous week' and information on size of servings was not requested. The results indicated poor agreement between the reference method and the FFQ methods. In contrast, agreement between the reference method and methods based on two or three diet records in the series was relatively good.

Determinants of blood pressure in childhood and adolescence.

Relationships between blood pressure and dietary factors were investigated in 434 boys and 450 girls aged 9 years. Dietary data were obtained from a food-frequency questionnaire which was completed by parents. This was used to estimate daily energy intake and the intake of 14 nutrients considered likely to influence blood pressure. Blood pressure was tested for relationships to absolute and calorie-adjusted intakes of each nutrient after adjustment for age, weight, height, socio-economic status and the month of examination. Ambient temperature was the most important determinant of blood pressure, an increase of 10 degrees C being associated with a 6-7 mmHg fall in blood pressure. Diastolic blood pressure in boys was negatively related to energy intake and to calorie-adjusted fibre intake. Mean adjusted diastolic blood pressure in boys in the top fibre intake quartile was 2.5 mmHg lower than that in the lowest quartile. Systolic blood pressure in girls was negatively related to calorie-adjusted intakes of protein. There were no relationships between blood pressure and calorie-adjusted intakes of fats, carbohydrates, sodium, potassium, calcium or magnesium.

Lifestyle- and occupation-related changes in blood pressure over a six-year period in a cohort of working men.

Determinants of change in blood pressure between two examinations separated by a 6-year period were investigated in 340 working men aged 20-45 at first examination and not on antihypertensive medication at either examination. A London School of Hygiene sphygmomanometer was used for all measurements of blood pressure. Relationships between change in blood pressure (residuals of follow-up blood pressure regressed on baseline blood pressure) and changes in weight, physical activity, cigarette smoking, diet, alcohol intake and a range of psychological characteristics were examined using multiple regression. Systolic and diastolic changes in blood pressure were both positively related to baseline age and weight. Regression equations indicated independent effects of change in weight, with similar increases of 0.5 (s.e. 0.1) mmHg in systolic and diastolic blood pressure for each kg of weight gain. Decreased coffee consumption and increased participation in sports were negatively associated with systolic changes in blood pressure. Men who had stopped smoking cigarettes were observed to have higher than average increases in both systolic and diastolic blood pressure, although these relationships were not independent of other variables. The difference in ambient temperature between baseline and follow-up measurement days was an important determinant of change. Changes in mean systolic and mean diastolic blood pressure in 76 manual workers (+10.1/+6.4 mmHg) compared unfavourably with changes in professional men (-2.8/+2.7 mmHg).(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol consumption, age and personality characteristics as important determinants of within-subject variability in blood pressure.

Intra-individual variability in blood pressure is well recognized but its determinants have been largely unexplored. In a recent cross-sectional study, 343 subjects from a male working population were assessed. Ten supine blood pressure readings were taken at 2-min intervals for 20 min on each of three consecutive days. Each subject's body mass index (weight/height2) was recorded and a questionnaire completed to record demographic details and information about physical activity, personality characteristics, dietary habits, tea and coffee consumption, smoking habits and alcohol consumption. When systolic and diastolic blood pressure variability was defined as the average coefficient of variation of the 10 readings each day, systolic blood pressure variability was found to be positively correlated with alcohol consumption, verbal aggression score and extroversion score. Diastolic variability was positively correlated with verbal aggression score, type-A personality score and extroversion score, and negatively associated with age. Stepwise regression analysis revealed alcohol consumption to be the strongest determinant of systolic variability while age was the strongest determinant of diastolic variability. We conclude that alcohol consumption, age and personality characteristics may be important determinants of intra-subject variability in blood pressure.

A randomized controlled trial of the effect on blood pressure of dietary non-meat protein versus meat protein in normotensive omnivores.

1. A randomized, controlled trial was carried out to examine whether changes in type and amount of dietary protein were responsible for earlier observations of blood-pressure-lowering effects of lacto-ovo-vegetarian diets. 2. Sixty-four subjects were pair-matched for sex, age, weight and sitting systolic blood pressure, and were randomly allocated to receive one of two types of protein supplement: one containing proteins from meat, the other proteins from non-meat sources. The supplements were balanced in terms of other nutrients. Consumption of other meat, poultry or fish was prohibited. 3. Sitting and standing blood pressures, weight, dietary intakes and plasma and urinary electrolytes were measured at regular intervals during the 12 weeks of trial. Urinary 3-methylhistidine was used as a measure of compliance. 4. Fifty subjects completed the trial. There were no statistically significant blood pressure differences between groups either at baseline or at end-of-trial, neither were there any substantive differences in mean blood pressure changes between baseline and end-of-trial. 3-Methyl-histidine excretion was significantly lower in subjects on the non-meat diet. 5. The results suggest that the protein components of the lacto-ovo-vegetarian diet are not responsible for the blood-pressure-lowering effects of that diet.

Diet and blood pressure in 9-year-old Australian children.

Relationships between blood pressure and dietary factors were investigated in 884 9-y-old Australian children. Data on usual diet were obtained from a food frequency questionnaire completed by parents. The data were used to estimate daily energy intake and intakes of 14 nutrients considered to have some potential for influencing blood pressure. Systolic and diastolic blood pressure were tested for relationships with absolute intakes and calorie-adjusted intakes of each nutrient after adjustment for potential confounders. Diastolic pressure in boys was negatively related to energy intake and to calorie-adjusted fiber intake. Mean adjusted diastolic pressure in boys in the top fiber-intake quartile was 2.5 mm Hg lower than that in the bottom fiber-intake quartile. Systolic pressure in girls was negatively related to calorie-adjusted intakes of protein and cholesterol. There were no detectable relationships between blood pressure and calorie-adjusted intakes of fats, carbohydrates, sodium, potassium, calcium, or magnesium.

An appraisal of the effects of usual vs recent alcohol intake on blood pressure.

1. In a population-based study of 343 men from two public utilities, 260 subjects reported drinking alcohol at least once a week. In these subjects a comparison was made of the relative effects on blood pressure of either their usual alcohol intake (assessed from a 7-day retrospective diary) or recent alcohol intake (alcohol consumed at the last drinking session in the 24 h prior to blood pressure measurement). 2. Both usual and recent alcohol intake showed similar correlations with level of blood pressure (BP). After adjustment of BP for the potential confounding influences of body mass index, age and smoking status, systolic and diastolic BP remained highest in those subjects with the highest reported levels of both usual and recent alcohol intake. 3. In regression analyses comprising only those subjects who reported drinking in the 24 h before BP measurement, a 3-4 fold greater effect of usual rather than recent intake on both systolic and diastolic BP was predicted from the b coefficients. Regression analysis also demonstrated that the relationship between usual alcohol intake and BP was independent of recent intake, while the relationship between recent intake and BP was no longer significant when usual alcohol intake was entered into the regression equation. 4. These observations suggest that consistent regular drinking is a more important determinant of the alcohol/BP relationship than intake in the previous 24 h.

A comparison of blood pressure measurements obtained with the Dinamap 845XT, the standard mercury sphygmomanometer and the London School of Hygiene device.

Blood pressure measurements obtained with the Dinamap 845XT Vital Signs monitor were compared with measurements obtained with a standard mercury sphygmomanometer and a London School of Hygiene mercury sphygmomanometer in a group of 31 normotensive and hypertensive subjects. The experimental design allowed reading to be taken with all 3 devices at approximately the same time. 12 sets of readings were obtained with each device in each subject. Although inter-device differences estimated from analysis of variance were small (less than 2 mmHg after allowing for calibration differences) differences between measurements taken simultaneously with the 3 devices were often substantial. Agreement between the two mercury sphygmomanometers was better than that between either sphygmomanometer and the Dinamap. This may be a reflection of fundamental differences between auscultatory and oscillometric measurements. Differences between devices were unrelated to blood pressure level. The observed variability within subjects was similar with each device.

Environmental temperature and blood pressure in 9-year-old Australian children.

Relationships between blood pressure (BP) and environmental temperature were investigated as part of a broader study of constitutional and environmental determinants of BP in a sample of 1037 9-year-old Australian children. A Dinamap semi-automatic device was used to obtain three BP readings for each child. Average systolic blood pressure (SBP) and diastolic blood pressure (DBP) differed according to month of examination, with higher levels in the colder months. Negative relationships were observed between BP and temperature on the measurement day; computed regression equations indicated that a rise in maximum daily temperature of 10 degrees C was associated with falls of 5-7 mmHg in SBP and DBP. The relationships were independent of age, weight, height, socio-economic status and heart rate (HR). The results emphasize the importance of taking environmental temperatures into account in epidemiological studies of BP.

24-h catecholamine excretion: relationships with age and weight.

24-hour urines were obtained from groups of volunteer subjects recruited from populations in the UK, USA, Nigeria and the South Pacific. Urines were collected during the course of normal daily activities. HPLC/electrochemical detection was used to measure concentrations of adrenaline and noradrenaline in each urine. Calculated 24-h output of catecholamines was tested for significant linear regression relationships with age, weight and 24-h urine volume in each population. Noradrenaline excretion tended to be positively related to age and to body wt. Adrenaline excretion tended to show little or no relationship with either age or body wt. Relationships based on catecholamine excretion/U creatinine were notably different to those based on absolute catecholamine excretion. Differences were observed in the nature and strength of the relationships in the different populations, indicating the likely importance of interactions with other factors.

Controlled study of the effects of dietary protein on blood pressure in normotensive humans.

1. The object of this study was to determine whether meat protein per se is responsible for the higher blood pressures (BP) in omnivores compared with vegetarians. 2. Assessments were made by a double blind randomized control trial in 64 normotensive volunteers recruited from Royal Perth Hospital staff. 3. All volunteers were given a 'meat' substitute during the 2 week control period. Randomization was then introduced into two dietary groups: the first remained on the 'meat' substitute, and the other received a 'non-meat' substitute of vegetable protein, for the remaining 12 weeks of the trial. 4. The content of 'meat' and 'non-meat' substitute was designed quantitatively and qualitatively to represent the protein intake in recently studied diets of Australian omnivores and ovo-lacto vegetarians, respectively. The levels of fats (saturated and unsaturated), fibre, energy, Na+, K+, Mg2+, Ca2+ and carbohydrate in the intervention diets were similar. 5. These dietary changes were not associated with any significant changes in BP. Significantly lower urinary 3-methyl histidine excretions in volunteers receiving 'non-meat' supplements compared with the 'meat' eaters confirmed the dietary changes. 6. It was concluded that BP differences between omnivores and accultured vegetarians are unlikely to be due to differences in protein intake.