Body mass index and screening for colorectal cancer: gender and attitudinal factors

Background: Overweight/obese women and men are at increased risk for colorectal cancer (CRC) incidence and mortality. Research examining body mass index (BMI) and CRC screening has had mixed results. A clearer understanding of the extent to which high-BMI subgroups are screened for CRC is needed to inform planning for CRC screening promotions targeting BMI. Methods: Data were obtained from a random, population-based sample of women and men at average-risk for CRC (aged 50–75 years) during 2004 (n = 1098). Multiple logistic regression analyses were conducted to evaluate whether BMI category was significantly associated with the probability of reporting recent CRC screening and with the probability of agreeing with statements denoting attitudes/perceptions about CRC and screening. Attitudes/perceptions about CRC and screening were evaluated as potential mediators and moderators of the association between BMI category and CRC screening. Results: After controlling for characteristics associated with CRC screening, overweight and obese women were each 40% less likely to have CRC screening than women with normal-BMI (OR = 0.6, 95% CI:0.4–0.9 and OR = 0.6, 95% CI:0.3–0.9). BMI category was unrelated to screening among men. Obese women (but not men) were less aware than normal-BMI women that obesity increased risk for CRC (OR = 0.5, 95% CI:0.3–0.9) and less worried about CRC (OR = 0.5, 95% CI:0.3–0.8). However, findings suggest that attitudes/perceptions about CRC and screening did not mediate or moderate the association between BMI category and CRC screening. Conclusion: Overweight/obese women are at increased risk for CRC because of their greater BMI and their propensity not to screen for CRC. Study findings suggest that potentially modifiable perceptions, e.g., lack of awareness of risk for CRC and less worry about CRC, in this subgroup may not explain the relationship between BMI category and reduced screening.     

Body mass index,iron absorption and iron status in childbearing age women

BackgroundThe prevalence of obesity has increased at an alarming rate worldwide. Some studies have observed an association between iron (Fe) deficiency (ID) and obesity, however more research is needed.ObjectiveTo assess whether body mass index (BMI) is associated with both Fe absorption and Fe status.MethodsA cross sectional sample of 318 Chilean childbearing age women was studied. The women received either a single dose of 0.5 mg of Fe (n = 137, group 1) or 3 mg of Fe plus ascorbic acid (1:2 molar ratio) (n = 181, group 2), both as FeSO₄ with labeled radioisotopes. Fe absorption was assessed through radio Fe erythrocyte incorporation. Fe status was determined by hemoglobin (Hb), mean corpuscular volume, serum Fe, total iron binding capacity, transferrin saturation, erythrocyte Zn protoporphyrin and serum ferritin (SF).Results29%, 47% and 24% of the women were classified as normal, overweight or obese, respectively. Fe absorption was significantly lower in obese women (p < 0.05). In group 1, the geometric mean and range ±1 SD of the percentage of Fe absorption for normal-weight women was 32.9% vs. 19.7% in obese. For group 2, this percentage was 36% vs. 30%, respectively (2-way ANOVA: BMI classification and Fe dose p < 0.05; interaction p = 0.34). Although Fe absorption was lower in obese women, they had higher SF (p < 0.01) and Hb (p < 0.05) concentrations.ConclusionAlthough we did not observe a relationship between BMI and Fe status, obese women displayed lower Fe absorption compared with overweight and normal weight women, possibly due to subclinical inflammation associated with obesity.     

Diet quality of middle age and older women from Primorsko-Goranska County evaluated by healthy eating index and association with body mass index

Accorded dietary habits provide adequate nutrient intakes, especially important for quality aging. Adequate nutrition for older persons has vital influence on maintaining good health and social functioning. Therefore, using simple tool for evaluation of diet of older population in relation to overweight and obesity is of public health importance. Among many factor that influence quality of aging has obesity, where in Croatia the prevalence of obesity is greater in older women than men. Our aim was to evaluate diet quality of middle age and older women from Primorsko-Goranska County by Healthy Eating Index (HEI) and to see the association of HEI to overweight and obesity. Diet quality of 124 women with average age 59.91 +/- 5.31 years was graded with 10 component HEI score, ranging from 0 to 100, where HEI score less than 51 implies "poor" diet. Overweight and obesity was classified according to WHO classification. The majority of women had diet that "needs improvement" (66.1%), and only 3.2% had "good" diet. Older women had better HEI score than middle-aged women, while overweight was statistically significant positively related to better HEI score (P = 0.26, p = 0.048). Older women better scored for meat, dairy, cholesterol and dietary variety. "Poor" diet mostly had women with normal weight and middle-aged. Age did not influenced overall HEI score, neither its components. Obese women had lower achievements for almost all recommended HEI components. Women having "poor" diet quality could raise a chance for overweight and obesity for almost two times ([OR] = 1.67, 95% [CI] = 1.072-2.59, p = 0.023; [OR] = 1.51, 95% [CI] = 1.08-2.10, p = 0.015, respectively). The provided results showed that with age, women tended to have better diet. These could be because of that with aging are higher disease incidences that essentially need diet improvements; so older women tended to improve their diet to reduce disease discomforts. Being obese influenced the diet quality of our sample of women, therefore, for quality aging, the importance of public health nutrition programs are strongly needed. HEI score is a good assessment for diet quality, but further investigation of influence on other sociodemographic and health characteristics is required.     

Body mass index and employment status: A new look

Earlier literature has usually modelled the impact of obesity on employment status as a binary choice (employed, yes/no). I provide new evidence on the impact of obesity on employment status by treating the dependent variable as a as a multinomial choice variable. Using data from a representative English survey, with measured height and weight on parents and children, I define employment status as one of four: working; looking for paid work; permanently not working due to disability; and, looking after home or family. I use a multinomial logit model controlling for a set of covariates. I also run instrumental variable models, instrumenting for Body Mass Index (BMI) based on genetic variation in weight. I find that BMI and obesity significantly increase the probability of “not working due to disability”. The results for the other employment outcomes are less clear. My findings also indicate that BMI affects employment through its effect on health. Factors other than health may be less important in explaining the impact of BMI/obesity on employment.     

Body mass index, socio-economic status and socio-behavioral practices among Tz’utujil Maya women

This study investigates the associations between body mass index (BMI), socio-economic status (SES) and related socio-behavioral practices including marriage and market visits in a population of adult Tz’utujil Maya women in Santiago Atitlán, Guatemala, aged 18-82. Mixed qualitative and quantitative methods include cross-sectional anthropometric measurements and semi-structured interviews gathered in 2007, as well as participant observation and purposive interviews conducted in 2007-2008. The regional quota sample of 53 semi-structured interviews was designed to be representative of the cantones (municipal divisions) of Santiago Atitlán. BMI was positively associated with years of schooling, income and literacy, all measures of SES. A statistical analysis of our data indicates that increased income, increased market visits and being married are significantly positively associated with BMI. Qualitative analysis based on the grounded theory method reveals relevant themes including a preoccupation with hunger and undernutrition rather than obesity, a preference for food quantity over dietary diversity, the economic and social influence of a husband, the effects of market distance and the increasing consumption of food from tiendas. These themes help to explain how SES, socio-behavioral practices and BMI are positively associated and can inform future public health interventions related to obesity and undernutrition.     

Body mass index related electrocardiographic findings in healthy young individuals with a normal body mass index

Introduction

An increased body mass index (BMI) (>25 kg/m²) is associated with a wide range of electrocardiographic changes. However, the association between electrocardiographic changes and BMI in healthy young individuals with a normal BMI (18.5–25 kg/m²) is unknown. The aim of this study was to evaluate the association between BMI and electrocardiographic parameters.

Methods

Data from 1,290 volunteers aged 18 to 30 years collected at our centre were analysed. Only subjects considered healthy by a physician after review of collected data with a normal BMI and in sinus rhythm were included in the analysis. Subjects with a normal BMI (18.5–25 kg/m²) were divided into BMI quartiles analysis and a backward multivariate regression analysis with a normal BMI as a continuous variable was performed.

Results

Mean age was 22.7 ± 3.0 years, mean BMI was 22.0, and 73.4% were male. There were significant differences between the BMI quartiles in terms of maximum P-wave duration, P-wave balance, total P-wave area in lead V1, PR-interval duration, and heart axis. In the multivariate model maximum P-wave duration (standardised coefficient (SC) = +0.112, P < 0.001), P-wave balance in lead V1 (SC = +0.072, P < 0.001), heart axis (SC = −0.164, P < 0.001), and Sokolow-Lyon voltage (SC = −0.097, P < 0.001) were independently associated with BMI.

Conclusion

Increased BMI was related with discrete electrocardiographic alterations including an increased P-wave duration, increased P-wave balance, a leftward shift of the heart axis, and decreased Sokolow-Lyon voltage on a standard twelve lead electrocardiogram in healthy young individuals with a normal BMI.

     

Longitudinal association of body mass index with lung function: The CARDIA Study

Background

Lung function at the end of life depends on its peak and subsequent decline. Because obesity is epidemic in young adulthood, we quantified age-related changes in lung function relative to body mass index (BMI).

Methods

The Coronary Artery Risk Development in Young Adults (CARDIA) study in 1985–86 (year 0) recruited 5,115 black and white men and women, aged 18–30. Spirometry testing was conducted at years 0, 2, 5 and 10. We estimated 10 year change in FVC, FEV₁ and FEV₁/FVC according to baseline BMI and change in BMI within birth cohorts with initial average ages 20, 24, and 28 years, controlling for race, sex, smoking, asthma, physical activity, and alcohol consumption.

Measurements and Main Results

Participants with baseline BMI < 21.3 kg/m² experienced 10 year increases of 71 ml in FVC and 60 ml in FEV₁ and neither measure declined through age 38. In contrast, participants with baseline BMI ≥ 26.4 kg/m² experienced 10 year decreases of 185 ml in FVC and 64 ml in FEV₁. FEV₁/FVC increased with increasing BMI. Weight gain was also associated with lung function. Those who gained the most weight over 10 years had the largest decrease in FVC, but FVC increased with weight gain in those initially thinnest. In contrast, FEV₁ decreased with increasing weight gain in all participants, with maximum decline in obese individuals who gained the most weight during the study.

Conclusion

Among healthy young adults, increasing BMI in the initially thin participants was associated with increasing then stable lung function through age 38, but there were substantial lung function losses with higher and increasing fatness. These results suggest that the obesity epidemic threatens the lung health of the general population.     

Chemokines and their association with body mass index among healthy Saudis

Obesity is a chronic disorder that is associated with body mass index (BMI) of greater or equal to 30 kg/m². The prevalence of obesity in the Kingdom of Saudi Arabia (KSA) is increasing at an alarming rate and is expected to reach 41% in men and up to 78% in women by 2022. Since chemokines are associated with involuntary weight loss, the objective of this study was to elucidate their association with BMI among Saudis. A questionnaire was used to collect information about diet, health conditions, and demographics from 15 men and 16 women who participated in the study. BMI was calculated based on clinical measurements and participants were classified according to their BMI category as: normal, underweight, overweight, or obese. Serum samples were collected for a multiplex assay using the Human Chemokine Magnetic 30-plex panel. The serum concentration of either the monokine induced by gamma interferon (MIG) or the CXC-motif chemokine ligand 9 (CXCL-9) was significantly increased in obese men (P = 0.0194) and women (P = 0.043) as compared to underweight men and women, respectively. However, the serum levels of other chemokines were not significantly different among the groups. We found that MIG levels are differentially regulated in serum, based on individuals’ BMI.     

Body mass index in Central India: inter district variation

Basic causes of poor state of nutrition and infections in developing countries are poverty, low level of hygienic conditions and little access to preventive and health care. Central India is known for its high rate of population growth and mortality, which persisted over time along with a low level of social, economic and infrastructure development. In the present study the body mass index (BMI) of 31 populations residing in 38 districts of Central India (comprising the States of Madhya Pradesh and Chhattisgarh) is assessed. Anthropometric data collected by the Anthropological Survey of India were utilized in this context. The mean body mass index values of the populations of total backward and non-backward districts are found to be lower than that of well-to-do individuals of India (Bharati 1989, Khongsdier 1997, Reddy 1998), but it is not as low as that found among the South Indian populations (Ferro-Luzzi et al. 1992). In the present investigation, it is also found that the majority of the backward districts fall in the category of different grade of chronic energy deficiency (CED), while in the non-backward districts a considerably less number of districts follows this trend. A better level of the nutritional status among the populations of the non-backward districts corroborates the findings of the Ministry of Health and Family Welfare (NFHS 1992). It reveals that the apparently healthy individuals with CED grade I in the present study may be thin but physically active and healthy. The present study, however, narrates further intensive investigations in these populations, because the BMI as a measure of the CED should incorporate the aspects like morbidity and health status of a population.     

Body mass index: risk predictor for cosmetic day surgery

Body mass index (BMI; weight per unit surface area) is the scientific yardstick by which overweight is gauged relative to the population norm. The contrary association between obesity and diabetes or hypertension is only too well known. Less appreciated is the heightened sensitivity to respiratory depressants such as sedatives and analgesics in the obese (BMI >/= 30) and the increased incidence of sleep apnea in the morbidly obese (BMI >/= 35)-either or both of which raise the risk of cosmetic surgery when sedation or anesthesia is contemplated. Guided by the BMI, a gender-independent measure of fatness, the surgeon now can inform the patient of her or his relative operative risk and offer an objective rationale for advising overnight hospitalization rather than office-based day surgery.The BMI is readily calculated when height and weight are expressed in metric units, much less so when measured in foot-pound units. In fact, the calculations are sufficiently cumbersome that the BMI remains underused in U.S. office surgery. The author's complimentary "BMI Calculator"-an Excel workbook available on-line to society members-is designed so that office staff need enter only height (in feet and inches) and weight (in pounds) to print the BMI for the patient's permanent record.The BMI places patient weight relative to height in proper perspective for aesthetic surgery, whether with sedation or under general anesthesia. The BMI ought to be as routine a part of the preoperative assessment as blood pressure or hemoglobin content.     

Decline in HIV prevalence among young women in Zambia: national-level estimates of trends mask geographical and socio-demographic differences

Background

A decline in HIV incidence has been reported in Zambia and a number of other sub-Saharan countries. The trend of HIV prevalence among young people is a good marker of HIV incidence. In this study, different data sources are used to examine geographical and sub-population group differentials in HIV prevalence trends among men and women aged 15–24 years in Zambia.

Design and Methods

We analysed ANC data for women aged 15–24 years from 22 sentinel sites consistently covered in the period 1994–2008, and HIV data for young men and women aged 15–24 years from the ZDHS 2001/2 and 2007. In addition, we systematically reviewed peer-reviewed articles that have reported findings on HIV prevalence and incidence among young people.

Findings

Overall trends of the ANC surveillance data indicated a substantial HIV prevalence decline among young women in both urban and rural areas. However, provincial declines differed substantially, i.e. between 10% and 68% among urban women, and from stability to 86% among rural women. Prevalence declines were steeper among those with the highest educational attainments than among the least educated. The ZDHS data indicated a significant reduction in prevalence between the two survey rounds among young women only. Provincial-level ZDHS changes were difficult to assess because the sample sizes were small. ANC-based trend patterns were consistent with those observed in PMTCT-based data (2002–2006), whereas population-based surveys in a selected urban community (1995–2003) suggested that the ANC-based data underestimated the prevalence declines in the general populations of both young both men and women.

Conclusion

The overall HIV prevalence declined substantially among young women in Zambia and this is interpreted as indicating a decline in HIV incidence. It is noteworthy that overall national trends masked substantial differences by place and by educational attainment, demonstrating critical limitations in the current focus on overall country-level trends in epidemiological reports.     

Body mass index and basal androstenedione are independent risk factors for miscarriage in polycystic ovary syndrome

Background

There is limited literature investigating the effects of body mass index (BMI) and androgen level on in vitro fertilization (IVF) outcomes with a gonadotropin-releasing hormone (GnRH)-antagonist protocol in polycystic ovary syndrome (PCOS). Androgen-related variation in the effect of body mass index (BMI) on IVF outcomes remains unknown.

Methods

In this retrospective study, 583 infertile women with PCOS who underwent IVF using the conventional GnRH-antagonist protocol were included. Patients were divided into four groups according to BMI and androgen level: overweight- hyperandrogenism(HA) group, n?=?96, overweight-non-HA group, n?=?117, non-overweight-HA group, n?=?152, and non-overweight-non-HA group, n?=?218.

Results

A significantly higher number of oocytes were retrieved, and the total Gn consumption as well Gn consumption per day was significantly lower, in the non-overweight groups than in the overweight groups. The number of available embryos was significantly higher in the HA groups than in the non-HA groups. Clinical pregnancy rate was of no significant difference among four groups. Live-birth rates in the overweight groups were significantly lower than those in non-overweight-non-HA group (23.9, 28.4% vs. 42.5%, P<0.05). The miscarriage rate in overweight-HA group was significantly higher than that in non-overweight-non-HA group (45.2% vs. 14.5%, P<0.05). Multivariate logistic regression analysis revealed that BMI and basal androstenedione (AND) both acted as significantly influent factors on miscarriage rate. The area under the curve (AUC) in receiver operating characteristic (ROC) analysis for BMI and basal AND on miscarriage rate were 0.607 (P?=?0.029) and 0.657 (P?=?0.001), respectively, and the cut-off values of BMI and basal AND were 25.335?kg/m² and 10.95?nmol/L, respectively.

Conclusions

In IVF cycles with GnRH-antagonist protocol, economic benefits were seen in non-overweight patients with PCOS, with less Gn cost and more retrieved oocytes. BMI and basal AND were both significantly influential factors with moderate predictive ability on the miscarriage rate. The predictive value of basal AND on miscarriage was slightly stronger than BMI.

     

Body mass index and depressive symptoms: instrumental‐variables regression with genetic risk score

The causal role of obesity in the development of depression remains uncertain. We applied instrumental‐variables regression (Mendelian randomization) to examine the association of adolescent and adult body mass index (BMI) with adult depressive symptoms. Participants were from the Young Finns prospective cohort study (n = 1731 persons, 2844 person‐observations), with repeated measurements of BMI and depressive symptoms (modified Beck's Depression Inventory). Genetic risk score of 31 single nucleotide polymorphisms previously identified as robust genetic markers of body weight was used as a proxy for variation in BMI. In standard linear regression analysis, higher adult depressive symptoms were predicted by higher adolescent BMI (B = 0.33, CI = 0.06–0.60, P = 0.017) and adult BMI (B = 0.47, CI = 0.32–0.63, P < 0.001). These associations were replicated in instrumental‐variables analysis with genetic risk score as instrument (B = 1.96, CI = 0.03–3.90, P = 0.047 for adolescent BMI; B = 1.08, CI = 0.11–2.04, P = 0.030 for adult BMI). The association for adolescent BMI was significantly stronger in the instrumented analysis compared to standard regression (P = 0.04). These findings provide additional evidence to support a causal role for high BMI in increasing symptoms of depression. However, the present analysis also demonstrates potential limitations of applying Mendelian randomization when using complex phenotypes.     

Body mass index and mortality in chronic obstructive pulmonary disease: a meta-analysis

Background

The association between body mass index (BMI) and mortality in patients suffering from chronic obstructive pulmonary disease (COPD) has been a subject of interest for decades. However, the evidence is inadequate to draw robust conclusions because some studies were generally small or with a short follow-up.

Methods

We carried out a search in MEDLINE, Cochrane Central Register of Controlled Trials, and EMBASE database for relevant studies. Relative risks (RRs) with 95% confidence interval (CI) were calculated to assess the association between BMI and mortality in patients with COPD. In addition, a baseline risk-adjusted analysis was performed to investigate the strength of this association.

Results

22 studies comprising 21,150 participants were included in this analysis. Compared with patients having a normal BMI, underweight individuals were associated with higher mortality (RR  = 1.34, 95% CI  = 1.01–1.78), whereas overweight (RR  = 0.47, 95% CI  = 0.33–0.68) and obese (RR  = 0.59, 95% CI  = 0.38–0.91) patients were associated with lower mortality. We further performed a baseline risk-adjusted analysis and obtained statistically similar results.

Conclusion

Our study showed that for patients with COPD being overweight or obese had a protective effect against mortality. However, the relationship between BMI and mortality in different classes of obesity needed further clarification in well-designed clinical studies.