The association of blood lead and blood pressure in population surveys

The association of age, body weight, body mass index (BMI) and glycosylated hemoglobin A1c (HbA1c) to blood pressure in the general population of the Ho-long area in Taiwan was examined. A total of 1341 subjects, 746 men and 595 women, aged 40-90 years, were studied. Sex-specific multiple regression analyses were carried out on variables both univariately and significantly associated with blood pressure. Results show HbA1c to be significantly associated with SBP in both males and females before age, weight and/or BMI are adjusted (p < 0.05). After controlling for these confounders, the strength of SBP-HbA1c association was slightly reduced in males, but remained significant. In contrast, there was no significance in females. Moreover, no significant relationship in DBP-HbA1c was found in either sex group. These findings suggest that although a positive correlation was found between HbA1c and SBP, HbA1c or glucose status appeared to be a less important contributing factor in hypertension than age or body weight.     

Gender effect of the Trp64Arg mutation in the beta 3 adrenergic receptor gene on weight gain in morbid obesity

Phenotypic expression of the Trp64Arg mutation in the beta 3-adrenoceptor gene (beta 3-AR) has been found to be somewhat variable among different populations, suggesting that it may be influenced by genetic background and environmental factors. As sex may also influence gene allellic expression, we evaluated a potential gender effect of the Trp64Arg mutation in 292 morbidly obese subjects [body mass index (BMI) > or = m/kg2]. Although the 15 mutated obese females were younger than the non-mutated ones, the difference between their current weight and their weight at 20 years was significantly higher (62.4 +/- 20.0 kg versus 47.0 +/- 24.0 kg; p = 0.017). Moreover, in the mutated heterozygous female group, the mean Zscore (individual BMI minus reference French population mean BMI/SD of reference population BMI) was significantly higher (8.0 +/- 2.5 versus 6.0 +/- 2.0 SD of BMI, p = 0.0018), as was the maximal Zscore calculated from the maximal BMI that obese females reached during life (9.0 +/- 3.0 versus 7.0 +/- 2.5, p = 0.005). The regression curves of the Zscore against age showed that the curve of mutated females was shifted to the top, indicating that their BMI was higher regardless of age. These effects were not observed in the male group (the Zscore was 6.7 +/- 3.0 vs. 7.2, p = 0.7 respectively in mutated and non-mutated men). These data reinforce the hypothesis that the expression of the beta 3-AR susceptibility gene depends on additional factors including gender and possibly hormonal status.     

Doppler sensors and harnesses for cardiac and peripheral arterial flow monitoring

This study sought to develop a maximal oxygen consumption (VO2max) regression model derived strictly from self-reported non-exercise (N-EX) predictor variables. The VO2max (mean +/- SD; 44.05 +/- 6.6 ml.kg-1.min-1) of 100 physically active college students (50 females, 50 males), aged 18 to 29 yr, was measured using a treadmill protocol and open circuit calorimetry. Questionnaire-based predictor variables used in the N-EX regression model included (a) the subject's perceived functional ability (PFA) to walk, jog, or run given distances, (b) habitual physical activity (PA-R) data, (c) body mass index (BMI), and (d) gender. BMI (kg.m-2) was computed from self-reported body weight in pounds and self-reported body height in feet and inches. The questionnaire-based N-EX regression model (R = 0.85, SEE = 3.44 ml.kg-1.min-1) developed in this study exceeded the accuracy of previously developed N-EX regression models and is comparable to many exercise-based regression models in the literature. Cross-validation using PRESS (predicted residual sum of squares) statistics demonstrated minimal shrinkage (R = 0.84, SEE = 3.60 ml.kg-1.min-1) of the present regression model. The PFA data were useful in explaining observed VO2max variance (squared partial r2 = 0.155, P < 0.0001) and enhanced the ability of the N-EX regression model to accurately predict criterion VO2max. These results suggest that a questionnaire-based N-EX regression model provides a valid and convenient method for predicting VO2max in physically active college students.     

Physical attractiveness, physical effectiveness, and self-concept in late adolescents

The differential role of various body attitudes in predicting the self-concepts of late adolescents (124 males and 218 females), enrolled in introductory psychology courses, was assessed. Subjects rated 24 body characteristics in terms of 1) how physically attractive they assumed these parts of their bodies were, and 2) how physically effective they assumed them to be; subjects also responded to a short self-concept scale. In accordance with the theory of Erikson (1968) and of McCandless (1970), it was expected that attractiveness attitudes should contribute more to the self-concepts of females than should effectiveness attitudes, while a reverse pattern of interrelatedness was expected for males. Results indicated a higher correspondence between what are seen as attractive body parts and what are viewed as effective body components for males than for females. Moreover, findings from step-wise multiple regression analyses of each sex group's ratings of the body parts for attractiveness and effectiveness, respectively, each with the criterion variable constituting mean self-concept score, were consistent with expectations. For females, the multiple correlation between attractiveness ratings and self-concept was greater than the multiple correlation between effectiveness ratings and self-concept, and more attractiveness variables than effectiveness variables were significant predictors of self-concept. The converse of these findings were obtained with the males' data. The relevance of these results for theories of personality development were discussed.     

Gender differences in adolescent sexual attitudes: the influence of individual and family factors

The present study, continuing a recent trend, examined multiple influences on adolescent sexuality, focusing on sexual attitudes because of their influence on sexual behavior. Empirical analyses were based on a nonrandom availability sample of 1,587 public high school students and 1,372 parents. Multiple regression analyses were conducted in three phases to elaborate models for adolescent attitudes about premarital sexual intercourse; separate models were developed for females and males. First, a regression model was developed that featured individual adolescent characteristics (e.g., age, gender, locus of control, self-esteem, and religious participation) as predictor variables. A second regression model was developed that included family characteristics (e.g., number of siblings, number of parents in home, communication with mother and father, family strengths, parent contribution to sexuality education, parental discussion of sexual values, and the sexual attitudes of mother and father). In the final step, multiple regression was conducted on both individual and family factors. Results indicated that (1) the integrated model had more explanatory power than either separate model, and (2) females were influenced by more family factors and males were influenced by more individual factors.     

Effects of gender, body composition, and menopause on plasma concentrations of leptin

Circulating concentrations of leptin ([leptin]) vary directly with body mass index and percentage body fat, and may thus constitute an afferent limb of a system regulating body fatness. We tested the hypotheses that: 1) Plasma [leptin] vary more directly with absolute fat mass than with fractional body fatness per se: and 2). The relationship between fat mass and [leptin] is significantly affected by gender and by menopausal status. [Leptin] in the post-absorptive state was examined in 67 subjects (26 male, 20 premenopausal female, 21 postmenopausal females; 43 never-obese, 24 obese) at usual body weight. Body composition was determined by hydrodensitometry, and [leptin] was determined by a double antibody ELISA assay. In male and pre-menopausal female subjects, subcutaneous adipose tissue aspirations were performed for determination of adipocyte volume by the osmium fixation method, and a 3 hour oral glucose tolerance tests was performed. At usual body weight, ([leptin]) was better correlated with absolute fat mass than with body mass index (BMI) or percentage body fat. BMI and % body fat did not account for any of the variance in [leptin] beyond that attributable to FM, per se. The regression equations relating FM to [leptin] did not differ significantly between obese and never-obese subjects. [Leptin] and fasting serum insulin concentrations were significantly correlated in males only. [Leptin] was significantly higher in pre- and post-menopausal females compared to males, even when [leptin] was corrected for differences in body composition (pre-menopausal females > post-menopausal females > males). While plasma [leptin], corrected for FM, declines significantly in women post-menopause, this decline is not sufficient to account for the striking sexual dimorphism in the relationship of leptin to fat mass. This sexual dimorphism is apparently also due, in part, to a suppressive effect of circulating androgens on [leptin].     

Defect in the induction of nitric oxide synthase by lipopolysaccharide (LPS) in an LPS-resistant mutant of a murine macrophage-like cell line, J774.1

OBJECTIVE: To investigate the issue of systematic bias in self-reported weight and height, and produce a simple procedure which can be used to correct reporting bias. DESIGN: Cross-sectional, with self-reported questionnaires. SUBJECTS: A sub-sample (n = 143) of secondary school students in Siena, Italy, taken from the Food Behaviour Survey (sample size, n = 779). RESULTS: In the teenage sub-sample, both males and females under-reported their weight and over-reported their height, such that underestimation of the overweight prevalence was in the order of about 8% for both genders. For both weight and height, the correlations between self-reported and measured values were over 0.90. Conversion factors were derived to correct the reported body mass index (BMI) distribution by adjusting the percentages of erroneously classified subjects in the four BMI categories. CONCLUSION: High correlation coefficients (r > or = 0.75), showing a systematic tendency for erroneous self-reporting of a 'slim-body shape', justify the use of conversion factors (measured/self-reported) to correct BMI distributions calculated from self-reported values.     

Combined effect of short stature and socioeconomic status on body mass index and weight gain during reproductive age in Brazilian women

Short stature, a marker for undernutrition early in life, has been associated with obesity in Brazilian women, but not in men. We tested the hypothesis that weight gain during the reproductive years could explain this gender difference. A national two-stage household survey of mothers with one or more children under five years of age was conducted in Brazil in 1996. The subjects were women aged 20 to 45 years (N = 2297), with last delivery seven months or more prior to the interview. The regions of the country were divided into rural, North/Northeast (urban underdeveloped) and South/Southeast/Midwest (urban developed). The dependent variables were current body mass index (BMI) measured, BMI prior to childbearing (reported), and BMI change. Socioeconomic variables included mother's years of education and family purchasing power score. A secondary analysis was restricted to primiparous women. The prevalence of current overweight and overweight prior to childbearing (BMI > or = 25 kg/m2) was higher among shorter women (<1.50 m) compared to normal stature women only in the urban developed region (P < 0.05). After adjustment for socioeconomic variables, age, parity, BMI prior to childbearing, and age at first birth, current BMI was 2.39 units higher (P = 0.008) for short stature women living in the urban developed area compared with short stature women living in the urban underdeveloped area. For both multiparous and primiparous women, BMI gain compared to the value prior to childbearing was significantly higher among short stature women living in the urban developed region (P <= 0.04). These results provide clear evidence that short stature was associated with a higher BMI and with an increased risk of weight gain/retention with pregnancy in the developed areas of Brazil, but not in the underdeveloped ones.     

Processes linking weight status and self-concept among girls from ages 5 to 7 years.

This study assessed the relationship between girls' weight status and self-concept and examined peer teasing and parent criticism as potential mediators of this relationship. Data were collected for 182 girls and their parents when the girls were 5 and 7 years old. At each age, girls' body mass index, self-concept, peer weight-related teasing (child report), and parents' criticism of girls' weight status (spouse report) were assessed. At ages 5 and 7, girls who were more overweight reported lower self-concept. Peer teasing and parent criticism mediated the relationship between weight status and self-concept at age 7, but not at age 5. In addition, the duration and timing of parent criticism across ages 5 and 7 mediated the association between girls' weight status at age 5 and perceived peer acceptance at age 7. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Human plasma leptin in obese subjects and diabetics

Leptin is the protein product of the ob gene, an adipocyte-specific gene, recently discovered in mice. Plasma leptin levels were determined in six normals, twenty-one subjects with impaired glucose tolerance, and forty-nine untreated NIDDM subjects. They increased with the augmentation of obesity (body mass index, BMI kg/m2) and were higher in females than in males: in BMI less than 25 kg/m2 the values of plasma leptin were 2.24 +/- 0.25 ng/ml (n=29) in males and 3.01 +/- 0.39 ng/ml (n=13) in females (P<0.054), respectively, in BMI between 25 kg/m2 and 30 kg/m2 they were 3.14 +/- 0.31 ng/ml (n=10) in males and 10.66 +/- 2.86 ng/ml (n=7) in females (P<0.0018) and in BMI higher than 30 kg/m2 their levels were 8.98 +/- 1.5 ng/ml (n=11) and 11.74 +/- 2.2 ng/ml (n=6) (P<0.23), respectively. The severity of diabetes mellitus judged from the fasting plasma glucose level had no influence on the plasma leptin levels during OGTT, but the leptin levels decreased significantly during a tolerance test (P<0.001), and similar results were also seen during a breakfast test. The fasting plasma leptin in the male with FBS less than 140 mg/dl had a significant correlation with the fasting plasma IRI level, but this correlation disappeared after taking obesity into consideration. Thus the plasma leptin was chiefly dependent on the body weight and gender and had no special relation to diabetic severity.     

Males with eating disorders: challenges for treatment and research

Males represent only 10 percent of eating disorder cases. This gender discrepancy is among the most extreme in psychiatry and medicine. Determining what differences in etiology and mechanism best explain the discrepancy presents an intellectual challenge. Beginning at about the third grade, boys and girls diverge in social development. Boys show significantly less desire to lose weight, express dissatisfaction with the upper rather than the lower body, and use dieting to achieve specific external goals rather than as a cultural norm. Males reach a significantly higher body mass index (BMI) than females do before they beginning dieting. (27.2 versus 24.3, p < .01). While overall treatment principles are similar, males in treatment require attainment of a different hormonal milieu (testosterone), attention to past and future sexual role, amelioration of perception of stigma, and preparation for return to male social roles. Males and females suffer comparable degrees of osteopenia and brain shrinkage during anorexia nervosa. The effectiveness of antidepressants in males with eating disorders (compared with that in females) has not been well studied. Male gender is not an adverse factor in short-term or long-term treatment outcome. Understanding the lower frequency of these illnesses in males may lead to more effective means of protecting girls from eating disorders and from the culturally induced distress about normal body size and shape that burdens adolescent development and adult life.     

Metaphor: the language of nursing researchers

BACKGROUND: The present study determines the association of obesity, gender, age and occupation in patients with carpal tunnel syndrome (CTS) in a New Zealand population. METHODS: Analysis of questionnaires and clinical review of patients who had undergone surgical decompression of the median nerve in the carpal tunnel. RESULTS: The age and gender distribution of 655 hands (512 patients) that had undergone carpal tunnel release (CTR) were compared with the age and gender distribution of the New Zealand population. The results indicate that the 3-year-period prevalence of CTS in females is more than double that in males. Proportionally there were more patients over age 55 than in the general population. The findings also indicate that, proportionally, six times the number of females who worked in moderate manual work underwent CTR compared with the general female population and proportionally twice the number of males who worked in heavy office/clerical work underwent CTR compared with the general male population. It was also found that CTR patients are twice as likely to be overweight (body mass index [BMI] > 25) than the general population and female patients are twice as likely to be obese (BMI > 30) than the general population. CONCLUSIONS: Carpal tunnel syndrome is more than twice as common in females as it is in males, and patients aged more than 55 years are more likely to suffer from CTS. Females with CTS are more likely to work in moderate manual work and males with CTS are more likely to work in heavy office/clerical work. Obesity and CTS are related statistically.     

The impact of the weight status on subjective symptomatology of the Polycystic Ovary Syndrome: a cross-cultural comparison between Brazilian and Austrian women

Group differences in symptomatology and symptom perception of young women ageing between 18 and 32 years suffering from polycystic ovarian syndrome (PCOS) were tested according to cultural background and weight status. In detail 31 Austrian women, living in Carinthia, Austria, and 102 Brazilian women, living in S?o Paulo, Brazil, were enrolled in the present study. All participants suffered from diagnosed PCOS. The prevalence of hirsutism, infertility, menstrual disturbances and overweight/obesity and their individual impact on health related quality of life were analysed. Furthermore the impact of weight status (BMI) on symptom perception was tested. It turned out, that the Brazilian sample exhibited higher prevalence of PCOS symptoms and these symptoms had a more negative impact on quality of life. The only exception was body weight. Although significantly leaner, the Austrian women showed a higher Cronin score of body weight than their Brazilian counterparts. The results of the present study may indicate that in western industrialized societies the fear of overweight is much more prevalent than in a developing country such as Brazil and thus it has more influence on the quality of life than all the other symptoms.     

Arterial hypertension in relation to life style and other cardiovascular risk factors. Epidemiologic study of a population of blood donors. Project AVIS

The objectives of this research were to determine the prevalence of essential and borderline hypertension in a population of blood donors and their families and to determine if there is a correlation between blood pressure and lifestyle and/or other cardiovascular risk factors. The study was comprised of 1976 individuals, of whom 1290 were men and 686 were women, aged 18-65 years. The prevalence of essential hypertension was 15.1% for males and 12.5% for females: the prevalence of borderline hypertension was 22.3% for males and 15.7% for females. The population was divided into two groups: the first group included only subjects (1170 men, 543 women) who did not regularly use drugs that could modify the blood pressure and the heart rate, the second group included the entire population. In the first group, the multiple regression analysis indicated, in order of importance: age, BMI (body mass index), and heart rate. These variables were important in determining the systolic blood pressure in both sexes, uricemia for males and glycemia for females. The diastolic blood pressure was dependent on BMI, heart rate, and alcohol in both sexes, and glycemia, LDL cholesterol, and uricemia in the men. In the second group, primary and borderline hypertension are significantly correlated with age, BMI, and uricemia in both sexes and glycemia in females. A program of health and nutritional education could modify some factors related to blood pressure, such as obesity and alcohol consumption. The result would be a reduction of the prevalence not only of essential and borderline hypertension, but also of metabolic diseases such as dyslipidaemias, diabetes and hyperuricemia, with a global reduction of the cardiovascular risk.     

Exercise and diet interventions improve perceptions of self in middle-aged adults

The effect of a 1-year exercise and diet intervention program on global self-concept, perceptions of the body, physical competence, exercise mastery, social competence, social comfort, and fitness was examined with 208 healthy individuals (191 males, 17 females) aged 39-49 years (mean age 44.9) with elevated risk factors for cardiovascular disease. The relative utility of the skill development versus the self-enhancement model of the self-concept/behaviour relationship was tested. The participants were randomized into four groups: diet (n = 53), diet and exercise (n = 64), exercise (n = 48) and no active intervention (n = 43). Measurements were made by the Harter adult self perception profile (HASPP) and the self-perception in exercise questionnaire (SPEQ). Two-way ANOVA analyses revealed that exercise participation, with or without diet, enhanced self-perceptions of physical mastery and ability, body perception, fitness and social comfort. The unique contribution of diet indicated enhanced body perception. No effect was found of diet or exercise on global self-concept. Exercise participation had a positive effect on perceptions of the self, and the higher the compliance with the exercise program, the stronger were the effects on the self-perceptions. This supported the skill development model of the self-concept/behaviour relationship. As the pretest self-concept scores did not predict exercise compliance, the self-enhancement model of the self-concept/behaviour relationship was not supported.     

The human FE65 gene: genomic structure and an intronic biallelic polymorphism associated with sporadic dementia of the Alzheimer type

This study aimed to investigate the relationship of systolic and diastolic blood pressure (BP) with a series of metabolic and nonmetabolic cardiovascular risk variables in a random sample of Turkish general adult population. Values of systolic and diastolic BP on the one hand and of six variables including body mass index (BMI), waist/hip ratio (W/H), grade of physical activity (PhA), plasma lipids and cigarette smoking from 1046 men and 1095 women aged 225 years were included in the analysis. Participants were classified into tertiles according to systolic and diastolic BP measurements, and were stratified in two age categories: 25-44 years (young) and 45-74 years (elderly). Plasma total cholesterol and triglyceride (Trg) concentrations were measured by the enzymatic method with the Reflotron apparatus. In multiple regression analysis, age proved the strongest independent determinant of BP. BMI was a strong independent marker of systolic and diastolic pressures in women, while in men the determinant value of the W/H was equivalent to BMI. For each increment of 1 kg/m2 of BMI was associated in men an increase of over 8 and 16 mmHg in diastolic and systolic pressure, respectively, regardless of age group. Corresponding figures in women were roughly 6 and 10 mmHg. Though plasma Trg were not independently associated with BP in either gender, the independent contribution of plasma cholesterol level in women to systolic and diastolic pressures was small but significant. BP was related to mean concentrations of plasma Trg in young adults only, total cholesterol levels were associated with diastolic pressure in young men only, whereas PhA grade was not associated with BP. These findings are consistent with the theory that, in the normal state, functions such as regulation of BP, body weight and lipid metabolism are closely linked to each other.     

Restricted maximum likelihood estimates of genetic parameters of adult male and female Rhode Island red chickens divergently selected for residual feed consumption

In adult chickens, feed intake can be predicted by multiple linear regression from body weight, change in body weight during the recording period (for males and females), and egg mass (for females). Residual feed consumption (RFC) is estimated by the deviation of observed from predicted values for feed intake. A divergent selection experiment has been conducted since 1975 in a Rhode Island Red population. Each sex was selected on the basis of its own RFC, Line R+ for high values of RFC and Line R- for low values. In addition to the traits measured to obtain RFC, egg production traits and body measurements (BM) have been recorded, including wattle length, shank length, and rectal temperature. After pooling data from the two lines and the base population, the data set included 1,064 males, each with 7 variables, and 3,780 females, each with 11 variables. Genetic parameters were estimated by a multivariate derivative-free-restricted maximum likelihood procedure, which yields estimates free of bias due to selection and inbreeding. The RFC appeared to be moderately heritable in males (h2 = .33) and in females (h2 = .27) and poorly correlated between sexes, with a genetic correlation of .19 between RFC in males (RFCm) and in females (RFCf). The RFCm and RFCf were weakly correlated with egg production traits. Significant, positive correlations were found between RFCm and the BM traits that were related to heat dissipation. Correlations between feed intake, body weight, and BM traits recorded in males or in females were always < 1, except for shank length.(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of diet, physical activity and parents' obesity on children's adiposity: a four-year longitudinal study

OBJECTIVE: To assess the relationships between diet, body composition, physical activity, parents' obesity and adiposity in children at the age of 8 y and four years later. STUDY DESIGN: Prospective observational study of anthropometric measures initiated in 1992, follow-up examination in 1996. METHODS: 112 prepubertal (age: 8.6 +/- 1.0 y) children were studied. Energy and nutrient intakes were assessed by diet history, body composition by anthropometry and physical activity, by a questionnaire. Obesity was defined as relative body mass index (BMI) (rel BMI) > 120%, where rel BMI = (BMI/BMI at 50th centile for age and gender) x 100. RESULTS: Prevalence of obesity was not statistically different at baseline (22.3%) than four years later (19.8%): rel BMI at the age of 8 y was positively self-related with rel BMI at the age of 12 y (r = 0.73, P < 0.001). After four years, eight (32%) obese children became non obese and five (6%) non obese children became obese. Multiple regression analysis (stepwise procedure) revealed that, in the final equation, the mother's BMI and TV viewing (independent variables) accounted for 17% of the children's rel BMI variance at the age of 8 y (R = 0.42, P < 0.001) while the parents' BMIs accounted for 13.5% of the children's rel BMI variance at the age of 12 y (R = 0.37, P < 0.001). Other variables such as total energy intake, nutrient intake percentage and amount of physical activity, were all rejected. An autoregressive unbalanced measures model regression analysis recognised the mother's and father's BMIs as the only variables able to predict rel BMI in the children (mother's BMI coeff. 2.53 (s.e.m. 0.26), P < 0.0001; father's BMI coeff. 2.07 (s.e.m. 0.23), P < 0.0001). A multivariate logistic regression analysis was also performed. The children who participated in the follow-up, were divided into two groups based on the positive or negative change in the rel BMI between final and baseline measurements. Of all the variables considered, only rel BMI at baseline was selected in the final equation. Other variables such as age, gender, energy and nutrient intake, TV viewing and amount of physical activity, as well as the parents' BMI, were all removed. CONCLUSIONS: The parents' obesity was the main risk factor for obesity in this group of children. Sedentary behaviour (TV viewing) was independently associated with overweight at the age of 8 y. Physical activity and energy and nutrient intakes did not significantly affect the change in rel BMI over the four-year period when the parents' obesity was taken into account.     

Ovarian neoplasia and subfertility treatments

OBJECTIVE: This study examines three specific questions about obesity and overweight, using a nationally representative sample of Canadians. Are sociodemographic and lifestyle behaviors associated with body weight? Is body weight correlated with specific health outcomes? Has the prevalence of obesity in Canada changed since 1978? METHODS: Secondary data analysis of a cross-sectional survey. SAMPLE: This study uses the 1994 National Population Health Survey (NPHS) by Statistics Canada. It is a stratified random sample of 19600 Canadians across all provinces. RESULTS: The results show that age, gender, education, birth place and region, are significantly associated with obesity. When a lower criterion is used for overweight and obesity (body mass index, BMI > or = 25), dummy variables for marital status and occupation are also significant. Second, obesity is associated with poorer self-rated health, high blood pressure, heart disease, diabetes, arthritis, respiratory and stomach problems. For those respondents who have a BMI score of 25 or greater, there is also an association with stroke. Finally, it is unclear whether the prevalence of obesity has changed. However, there appears to be a systematic difference between studies using actual height and weight measurements (anthropometric) vs self-reported measurements. CONCLUSIONS: Weight can be considered a modifiable risk factor and reductions in the prevalence of obesity should reduce the risk of specific chronic conditions. Provincial variations in the prevalence of obesity (BMI > or = 27) and overweight and obesity (BMI > or = 25) suggest that collapsing provinces into regions may obscure important inter-provincial differences in body weight. More research is required to assess whether or not obesity is decreasing in Canada. Some of the limitations of self-reported data are discussed.     

Gender gap in cystic fibrosis mortality

The authors conducted the largest study to date of survival in cystic fibrosis. The study cohort consisted of all patients with cystic fibrosis seen at Cystic Fibrosis Foundation-accredited care centers in the United States between 1988 and 1992 (n = 21,047), or approximately 85% of all US patients diagnosed with cystic fibrosis. Cox proportional hazards regression analysis was used to compare the age-specific mortality rates of males and females and to identify risk factors serving as potential explanatory variables for the gender-related difference in survival. Among the subjects 1-20 years of age, females were 60% more likely to die than males (relative risk = 1.6, 95% confidence interval 1.4-1.8). Outside this age range, male and female survival rates were not significantly different. The median survival for females was 25.3 years and for males was 28.4 years. Nutritional status, pulmonary function, and airway microbiology at a given age were strong predictors of mortality at subsequent ages. Nonetheless, differences between the genders in these parameters, as well as pancreatic insufficiency, age at diagnosis, mode of presentation, and race, could not account for the poorer survival among females. Even after adjustment for all these potential risk factors, females in the age range 1-20 years remained at greater risk for death (relative risk = 1.6, 95% confidence interval 1.2-2.1). The authors concluded that in 1- to 20-year-old individuals with cystic fibrosis, survival in females was poorer than in males. This "gender gap" was not explained by a wide variety of potential risk factors.