Intraocular Pressure and Estimated Cerebrospinal Fluid Pressure. The Beijing Eye Study 2011

Purpose

To examine a potential association between intraocular pressure (IOP) and cerebrospinal fluid pressure (CSFP) in a population-based setting.

Methods

The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50–93 years). A detailed ophthalmic examination was performed. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP) measurements, CSFP was calculated as CSFP [mm Hg] = 0.44×Body Mass Index [kg/m²]+0.16×Diastolic Blood Pressure [mm Hg]–0.18×Age [Years].

Results

In multivariate analysis, IOP was associated with higher estimated CSFP (P<0.001; standardized correlation coefficient beta: 0.27; regression coefficient B: 0.20; 95% confidence interval (CI): 0.16, 0.24), after adjusting for thinner central corneal thickness (P<0.001; beta: 0.45; B: 0.04;95%CI: 0.04,0.04), smaller corneal curvature radius (P<0.001; beta:−0.11; B:−1.13;95%CI:−1.61,−0.64), shallower anterior chamber depth (P = 0.01; beta:−0.05; B:−0.33;95%CI:−0.59,−0.08) and longer axial length (P = 0.002; beta: 0.08; B: 0.20;95%CI: 0.08,0.32)), and after adjusting for the systemic parameters of higher pulse rate (P<0.001; beta: 0.08; B: 0.02;95%CI: 0.01,0.03), higher prevalence of arterial hypertension (P = 0.002; beta: 0.06; B: 0.32;95%CI: 0.12,0.53)), frequency of drinking alcohol (P = 0.02; beta: 0.04; B: 0.09;95%CI: 0.01,0.17), higher blood concentration of triglycerides (P = 0.001; beta: 0.06; B: 0.06;95%CI: 0.02,0.10) and cholesterol (P = 0.049; beta: 0.04; B: 0.08;95%CI: 0.00,0.17), and body mass index (P<0.001; beta:−0.13; B:−0.09;95%CI:−0.13,−0.06). In a parallel manner, estimated CSFP (mean: 10.8±3.7 mm Hg) was significantly associated with higher IOP (P<0.001; beta: 0.13; B: 0.18;95%CI: 0.13,0.23) after adjusting for rural region of habitation (P<0.001; beta:−0.37; B:−2.78;95%CI:−3.07,−2.48), higher systolic blood pressure (P<0.001; beta: 0.34; B: 0.06;95%CI: 0.05,0.07), higher pulse rate (P = 0.003; beta: 0.05; B: 0.02;95%CI: 0.01,0.03), taller body height (P<0.001; beta: 0.11; B: 0.05;95%CI: 0.03,0.07), higher blood concentration of cholesterol (P = 0.003; beta: 0.05; B: 0.17;95%CI: 0.06,0.28) and higher level of education (P = 0.003; beta: 0.09; B: 0.30;95%CI: 0.16,0.45).

Conclusions

IOP was positively associated with estimated CSFP after adjusting for other ocular and systemic parameters. As a corollary, higher estimated CSFP was significantly associated with higher IOP in multivariate analysis. It fits with the notion that the arterial blood pressure, estimated CSFP and IOP are physiologically correlated with each other.     

Intraocular Pressure and Associations in Children. The Gobi Desert Children Eye Study

Purpose

To assess the intraocular pressure (IOP) and its association in children in a population living in an oasis in the Gobi Desert.

Methods

The cross-sectional school-based study included all schools in the Ejina region. The children underwent an ophthalmic examination, non-contact tonometry and measurement of blood pressure and body height and weight.

Results

Out of eligible 1911 children, 1565 (81.9%) children with a mean age of 11.9±3.5 years (range: 6–21 years) participated. Mean spherical refractive error was −1.58±2.00 diopters. In multivariate analysis, higher IOP (right eye) was associated with younger age (P<0.001; standardized coefficient beta: −0.13; regression coefficient B: −0.13; 95% Confidence interval (CI):−0.18, −0.07), higher diastolic blood pressure (P<0.001;beta:0.13;B:0.05;95%CI:0.03,0.07), higher corneal refractive power (P<0.001;beta:0.11;B:0.23;95%CI:0.12,0.34), more myopic refractive error (P = 0.035;beta: −0.06;B: −0.10;95%CI: −0.19, −0.001), and Han Chinese ethnicity of the father (P = 0.03;beta:0.06;B:0.42;95%CI:0.04,0.89). If age and diastolic blood pressure were dropped, higher IOP was associated with higher estimated cerebrospinal fluid pressure (CSFP) (P<0.001;beta:0.09; B:0.13;95%CI:0.06,0.21) after adjusting for higher corneal refractive power (P<0.001) and Han Chinese ethnicity of the father (P = 0.04). Correspondingly, higher IOP of the left eye was associated with younger age (P<0.001;beta: −0.15;B: −0.16;95%CI: −0.21, −0.10), female gender (P<0.001;beta:0.09;B:0.65;95%CI:0.30,1.01), higher corneal refractive power (P<0.001;beta:0.08;B:0.19;95%CI:0.06,0.32), more myopic refractive error (P = 0.03;beta: −0.06;B: −0.12;95%CI: −0.22, −0.01), and higher estimated CSFP (P<0.001;beta:0.11;B:0.17;95%CI:0.09,0.24).

Conclusions

In school children, higher IOP was associated with steeper corneal curvature and with younger age and higher blood pressure, or alternatively, with higher estimated CSFP. Corneal curvature radius should be included in the correction of IOP measurements. The potential association between IOP and CSFP as also assumed in adults may warrant further research.     

Body Height,Estimated Cerebrospinal Fluid Pressure and Open-Angle Glaucoma. The Beijing Eye Study 2011

Purpose

To examine potential associations between body height, cerebrospinal fluid pressure (CSFP), trans-lamina cribrosa pressure difference (TLCPD) and prevalence of open-angle glaucoma (OAG) in a population-based setting.

Methods

The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range:50–93 years). A detailed ophthalmic examination was performed. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP) measurements, CSFP was calculated as CSFP[mmHg] = 0.44×Body Mass Index[kg/m²]+0.16×Diastolic Blood Pressure[mmHg]-0.18×Age[Years]-1.91

Results

Data of IOP and CSFP were available for 3353 (96.7%) subjects. Taller body height was associated with higher CSFP (P<0.001; standardized correlation coefficient beta:0.13; regression coefficient B:0.29; 95% confidence interval (CI):0.25,0.33) after adjusting for male gender, urban region of habitation, higher educational level, and pulse rate. If TLCPD instead of CSFP was added, taller body height was associated with lower TLCPD (P<0.001;beta:−0.10;B:−0.20;95%CI:−0.25,−0.15). Correspondingly, higher CSFP was associated with taller body height (P = 0.003;beta:0.02;B:0.01;95%CI:0.00,0.02), after adjusting for age, gender, body mass index, pulse, systolic blood pressure, and blood concentration of cholesterol. If IOP was added to the model, higher CSFP was associated with higher IOP (P<0.001;beta:0.02;B:0.02;95%CI:0.01,0.03). TLCPD was associated with lower body height (P = 0.003;beta:−0.04;B −0.02,95%CI:−0.04,−0.01) after adjusting for age, body mass index, systolic blood pressure, pulse, blood concentrations of triglycerides, axial length, central corneal thickness, corneal curvature radius, and anterior chamber depth. Adding the prevalence of OAG to the multivariate analysis revealed, that taller body height was associated with a lower OAG prevalence (P = 0.03;beta:−0.03;B:−1.20;95%CI:−2.28,−0.12) after adjusting for educational level and gender.

Conclusions

Taller body height was associated with higher CSFP and lower TLCPD (and vice versa), after adjusting for systemic and ocular parameters. Parallel to the associations between a higher prevalence of glaucoma with a lower CSFP or higher TLCPD, taller body height was associated with a lower prevalence of OAG.     

Urinary Triclosan is Associated with Elevated Body Mass Index in NHANES

Background

Triclosan—a ubiquitous chemical in toothpastes, soaps, and household cleaning supplies—has the potential to alter both gut microbiota and endocrine function and thereby affect body weight.

Methods

We investigated the relationship between triclosan and body mass index (BMI) using National Health and Nutrition Examination Surveys (NHANES) from 2003–2008. BMI and spot urinary triclosan levels were obtained from adults. Using two different exposure measures—either presence vs. absence or quartiles of triclosan—we assessed the association between triclosan and BMI. We also screened all NHANES serum and urine biomarkers to identify correlated factors that might confound observed associations.

Results

Compared with undetectable triclosan, a detectable level was associated with a 0.9-point increase in BMI (p<0.001). In analysis by quartile, compared to the lowest quartile, the 2nd, 3rd and 4th quartiles of urinary triclosan were associated with BMI increases of 1.5 (p<0.001), 1.0 (p = 0.002), and 0.3 (p = 0.33) respectively. The one strong correlate of triclosan identified in NHANES was its metabolite, 2,4-dichlorophenol (ρ = 0.4); its association with BMI, however, was weaker than that of triclosan. No other likely confounder was identified.

Conclusions

Triclosan exposure is associated with increased BMI. Stronger effect at moderate than high levels suggests a complex mechanism of action.     

Age-Related Changes of Intraocular Pressure in Elderly People in Southern China: Lingtou Eye Cohort Study

Purpose

To study age-related changes of intraocular pressure (IOP) and assess the cohort effect in both cross-sectional and longitudinal settings among elderly Chinese adults.

Methods

Participants were enrolled from the Lingtou Eye Cohort Study with Chinese government officials aged 40 years and older at baseline and received physical check-up and ocular examinations from 2010 to 2012. IOP was measured using a non-contact tonometer according to standardized protocols, as well as systolic blood pressure (SBP), diastolic blood pressure (DBP) and body mass index (BMI). Participants who had attended IOP measurements in both 2010 and 2012 were included in this study. Cross-sectional association of IOP with age was assessed using multivariate liner regression analyses and based on the data of 2010. Longitudinal changes in IOP were assessed by paired t-test.

Results

A total of 3372 subjects were enrolled in the current analysis (2010 mean [SD] age, 61.9 [7.1] years; 60.2% men). The mean IOP in 2010 was 15.4±2.3 mmHg for women and 15.2±2.3 mmHg for men with an intersex difference (P = 0.029). Cross-sectional analysis showed that IOP was negatively associated with age (P = 0.003, β = -0.033 for women and P<0.001, β = -0.061 for men) adjusted for baseline SBP, DBP and BMI. Paired t-test suggested that IOP was higher in the year 2012 than 2010 in women (P = 0.006) but did not change significantly in men within 2 years (P = 0.345). In addition, the 2-year changes of IOP were not associated with age adjusted for baseline IOP in 2010 (P = 0.249).

Conclusion

Cross-sectional data suggests that IOP is lower in people with older age. Longitudinal data does not support such findings and thus the identified decreasing pattern with age in cross-sectional analysis is likely caused by cohort effects.     

Diabetic Retinopathy and Estimated Cerebrospinal Fluid Pressure. The Beijing Eye Study 2011

Purpose

The cerebrospinal fluid pressure (CSFP) is a major determinant of central retinal vein pressure and thus of retinal capillary pressure. We tested the hypothesis whether prevalence and severity of diabetic retinopathy are associated with CSFP.

Methods

The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years. A detailed ophthalmic examination was performed including fundus photography for the assessment of diabetic retinopathy according. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP) measurements, CSFP was calculated as CSFP[mmHg] = 0.44xBody Mass Index[kg/m²]+0.16 Diastolic Blood Pressure[mmHg]–0.18xAge[Years]−1.91.

Results

In binary regression analysis, presence of diabetic retinopathy was significantly associated with higher levels of HbA1c (P<0.001; regression coefficient B:0.25; odds ratio (OR):1.28; 95% confidence interval (CI):1.15,1.43), higher blood concentration of glucose (P<0.001; B:0.40;OR:1.49;95%CI:1.36,1.63), longer known duration of diabetes mellitus (P<0.001; B:0.14;OR:1.15; 95%CI:1.11,1.19), higher systolic blood pressure (P<0.001; B:0.03;OR:1.03;95%CI:1.02,1.04), lower diastolic blood pressure (P<0.001; B:−0.06;OR:0.94;95%CI:0.91,0.97), and higher CSFP (P = 0.002; B:0.13;OR:1.14;95%CI:1.05,1.24). Severity of diabetic retinopathy was significantly associated with higher HbA1c value (P<0.001; standardized coefficient beta: 0.19; correlation coefficient B: 0.07;95%CI:0.05,0.08), higher blood concentration of glucose (P<0.001; beta:0.18;B:0.04;95%CI:0.04,0.05), longer known duration of diabetes mellitus (P<0.001; beta:0.20;B:0.03;95%CI:0.02,0.03), lower level of education (P = 0.001; beta:−0.05;B:−0.02;95%CI:−0.03,−0.01), lower diastolic blood pressure (P = 0.002; beta:−0.08;B:−0.001;95%CI:−0.004,−0.001), higher systolic blood pressure (P = 0.006; beta:0.06;B:0.001;95%CI:0.000,0.001), and higher CSFP (P = 0.006; beta:0.06;B:0.006;95%CI:0.002,0.010).

Conclusions

Higher prevalence and severity of diabetic retinopathy were associated with higher estimated CSFP after adjusting for systemic parameters. Higher CSFP through a higher retinal vein pressure may lead to more marked retinal venous congestion and vascular leakage in diabetic retinae.     

Body Mass Index Is Associated with Physical Performance in Suburb-Dwelling Older Chinese: A Cross-Sectional Study

Background

Physical performance is reported to have various beneficial effects on human health, especially in older individuals. Although such effects are associated with body mass index (BMI), the relationship between BMI and physical performance has not been clarified.

Design

We conducted a cross-sectional study of 966 suburb-dwelling Tianjin individuals aged ≥ 60 years (average age 67.5±6.02, men 435, women 531). Mobility, balance, and muscle strength were assessed by walking speed, timed up-and-go test (TUGT), and grip strength, respectively. The subjects were categorized into three groups based on BMI (kg/m²) as follows: normal weight, 18.5 ≤ BMI ≤ 23.9; overweight, 24.0 ≤ BMI ≤ 27.9; and obese, BMI ≥ 28.0.

Result

After adjusting for all other variables, relative grip strength decreased when BMI increased in both men and women (P for trend <0.001 and <0.001, respectively). BMI may be negatively associated with TUGT performance in the women only. There was no apparent association between walking speed and BMI in either sex, but after adjusting for age, walking speed was faster when BMI increased in women (P for trend= 0.0162).

Conclusion

This study suggests that in older individuals, higher BMI is associated with poor muscle strength in both sexes.     

Identification of POMC Exonic Variants Associated with Substance Dependence and Body Mass Index

Background

Risk of substance dependence (SD) and obesity has been linked to the function of melanocortin peptides encoded by the proopiomelanocortin gene (POMC).

Methods and Results

POMC exons were Sanger sequenced in 280 African Americans (AAs) and 308 European Americans (EAs). Among them, 311 (167 AAs and 114 EAs) were affected with substance (alcohol, cocaine, opioid and/or marijuana) dependence and 277 (113 AAs and164 EAs) were screened controls. We identified 23 variants, including two common polymorphisms (rs10654394 and rs1042571) and 21 rare variants; 12 of which were novel. We used logistic regression to analyze the association between the two common variants and SD or body mass index (BMI), with sex, age, and ancestry proportion as covariates. The common variant rs1042571 in the 3′UTR was significantly associated with BMI in EAs (Overweight: P _adj = 0.005; Obese: P _adj = 0.018; Overweight+Obese: P _adj = 0.002) but not in AAs. The common variant, rs10654394, was not associated with BMI and neither common variant was associated with SD in either population. To evaluate the association between the rare variants and SD or BMI, we collapsed rare variants and tested their prevalence using Fisher’s exact test. In AAs, rare variants were nominally associated with SD overall and with specific SD traits (SD: P _FET,1df = 0.026; alcohol dependence: P _FET,1df = 0.027; cocaine dependence: P _FET,1df = 0.007; marijuana dependence: P _FET,1df = 0.050) (the P-value from cocaine dependence analysis survived Bonferroni correction). There was no such effect in EAs. Although the frequency of the rare variants did not differ significantly between the normal-weight group and the overweight or obese group in either population, certain rare exonic variants occurred only in overweight or obese subjects without SD.

Conclusion

These findings suggest that POMC exonic variants may influence risk for both SD and elevated BMI, in a population-specific manner. However, common and rare variants in this gene may exert different effects on these two phenotypes.     

HbA1c and Blood Pressure Measurements: Relation with Gender,Body Mass Index,Study Field,and Lifestyle in Lebanese Students

Objective: The purpose of this study is to determine the prevalence of prediabetes/diabetes in Lebanese university students and to examine the relationship between both hemoglobin A1c (HbA1c) and blood pressure (BP) and gender, body mass index (BMI), study field, and lifestyle factors.Methods: This cross-sectional study was carried out at the Saint-Joseph University of Beirut. A total of 603 students aged 18 to 25 years were recruited from both the medical science campus (MSC) and the social science campus (SSC) between January, 2016, and May, 2018. Waist circumference (WC), BMI, and BP were determined for each student and HbA1c was measured using the Siemens vintage DCA device. Participants completed a self-administered questionnaire about their eating habits and level of physical activity.Results: The mean age of the population was 20.31 ± 1.76 years. The percentage of participants recruited from the MSC was 59.2%. The prevalence of prediabetes was 2.5%. Lower BMI, WC, and HbA1c values, and higher diastolic BP (DBP) were found in MSC students compared to SSC ones. HbA1c, systolic BP (SBP), and DBP were correlated with BMI (P = .02, P<.0001, and P = .017, respectively). HbA1c was not associated with eating habits or physical activity. DBP was inversely associated with physical activity (P = .002), while SBP was positively associated with fast food consumption (P = .003).Conclusion: The present study shows a low prevalence of prediabetes in Lebanese students. BMI and the study field are the main factors predicting HbA1c and BP. Further studies are needed to extrapolate our results to the overall young Lebanese population.Abbreviations: ADA = American Diabetes Association; BMI = body mass index; BP = blood pressure; DBP = diastolic blood pressure; HbA1c = hemoglobin A1c; HTN = hypertension; MSC = medical science campus; SBP = systolic blood pressure; SSC = social science campus; T2D = type 2 diabetes; US = United States; USJ = Saint-Joseph University; WC = waist circumference     

The Multiplex Genotyping Method for Single-Nucleotide Polymorphisms of Genes Associated with Obesity and Body Mass Index

Russian Journal of Genetics - Obesity is one of the global health problems resulting in significant economic and social damage in both developed and developing countries. Overweight and obesity are...     

Factors Associated with Myopia in School Children in China: The Beijing Childhood Eye Study

Purpose

To assess factors associated with myopia in school children in rural and urban parts of Greater Beijing.

Methods

The Beijing Pedriatic Eye Study was a population-based cross-sectional study, in which one school of each level (primary, junior high, senior high) was randomly selected from nine randomly selected districts out of 18 districts of Greater Beijing. The children underwent non-cylcoplegic refractometry and their parents an interview.

Results

Of 16,771 eligible students, 15,066 (89.8%) children (7,769 (51.6%) girls) participated, with 8,860 (58.8%) participants living in the rural region. Mean age was 13.2±3.4 years (range:7–18 years). In multivariate analysis, prevalence of myopia (defined as ≤−1.00 diopters) was associated with higher age (Odds ratio(OR):1.37; 95% confidence interval(CI):1.35,1.39), female gender (OR:1.35;95%CI:1.25,1.47), key school type (OR:0.77;95%CI: 0.70,0.85), higher family income (OR:1.04;95%CI:1.01,1.07), parental myopia (OR:1.46;95%CI:1.40,1.53), dim reading illumination (OR:0.93;95%CI: 0.88,0.98), longer daily studying duration (OR:1.10;95%CI:1.06,1.15), shorter duration of watching television (or computer) (OR:0.93;95%CI:0.89,0.97), higher self-reported protein intake (OR:0.94;95%CI:0.90,0.99), feeling well about life and status (OR:0.93;95%CI:0.89,0.98), and feeling tired or dizzy (OR:0.94;95%CI:0.91,0.97). Prevalence of high myopia (defined as ≤−6.00 diopters) was associated with higher age (OR:1.43;95%CI:1.38, 1.48), key school type (OR:0.61;95%CI:0.49,0.74), family income (OR:1.07;95%CI:1.02,1.13), parental myopia (OR:1.65;95%CI:1.54,1.76), dim reading illumination (OR:0.86;95%CI:0.77,0.96), less rest during studying (OR:1.18;95%CI:1.10,1.27), feeling well about life and studying (OR:0.88;95%CI: 0.81,0.96) and feeling dizzy or tired (OR:0.93;95%CI:0.87,0.99). Prevalence of high myopia (defined as ≤−8.00 diopters) was significantly associated with higher age (OR:1.39;95%CI:1.31,1.48;), key school type (OR:0.61;95%CI:0.42,0.88) and parental myopia (OR:1.87;95%CI:1.66,2.12).

Conclusions

Myopia in school children in Greater Beijing was associated with higher age, female gender, school type, parental myopia, higher socioeconomic background, dim reading illumination, longer daily studying duration, less rest during study, shorter duration of watching television (or computer), higher self-reported protein intake, feeling well about life and status, and feeling tired and dizzy.     

Genetic Variation in the NOC Gene Is Associated with Body Mass Index in Chinese Subjects

Circadian clock genes are critical regulators of energy homeostasis and metabolism. However, whether variation in the circadian genes is associated with metabolic phenotypes in humans remains to be explored. In this study, we systemically genotyped 20 tag single nucleotide polymorphisms (SNPs) in 8 candidate genes involved in circadian clock, including CLOCK, BMAL1(ARNTL), PER1, PER2, CRY1, CRY2, CSNK1E,, and NOC(CCRN4L) in 1,510 non-diabetic Chinese subjects in Taipei and Yunlin populations in Taiwan. Their associations with metabolic phenotypes were analyzed. We found that genetic variation in the NOC gene, rs9684900 was associated with body mass index (BMI) (P = 0.0016, Bonferroni corrected P = 0.032). Another variant, rs135764 in the CSNK1E gene was associated with fasting glucose (P = 0.0023, Bonferroni corrected P = 0.046). These associations were consistent in both Taipei and Yunlin populations. Significant epistatic and joint effects between SNPs on BMI and related phenotypes were observed. Furthermore, NOC mRNA levels in human abdominal adipose tissue were significantly increased in obese subjects compared to non-obese controls.

Conclusion

Genetic variation in the NOC gene is associated with BMI in Chinese subjects.     

Aged-Related Changes in Body Composition and Association between Body Composition with Bone Mass Density by Body Mass Index in Chinese Han Men over 50-year-old

Objectives

Aging, body composition, and body mass index (BMI) are important factors in bone mineral density (BMD). Although several studies have investigated the various parameters and factors that differentially influence BMD, the results have been inconsistent. Thus, the primary goal of the present study was to further characterize the relationships of aging, body composition parameters, and BMI with BMD in Chinese Han males older than 50 years.

Methods

The present study was a retrospective analysis of the body composition, BMI, and BMD of 358 Chinese male outpatients between 50 and 89 years of age that were recruited from our hospital between 2009 and 2011. Qualified subjects were stratified according to age and BMI as follows: 50–59 (n = 35), 60–69 (n = 123), 70–79 (n = 93), and 80–89 (n = 107) years of age and low weight (BMI: < 20 kg/m²; n = 21), medium weight (20 ≤ BMI < 24 kg/m²; n = 118), overweight (24 ≤ BMI < 28 kg/m²; n = 178), and obese (BMI ≥ 28 kg/m²; n = 41). Dual-energy X-ray absorptiometry (DEXA) was used to assess bone mineral content (BMC), lean mass (LM), fat mass (FM), fat-free mass (FFM), lumbar spine (L1-L4) BMD, femoral neck BMD, and total hip BMD. Additionally, the FM index (FMI; FM/height²), LM index (LMI; LM/height²), FFM index (FFMI; [BMC+LM]/height²), percentage of BMC (%BMC; BMC/[BMC+FM+LM] × 100%), percentage of FM (%FM; FM/[BMC+FM+LM] × 100%), and percentage of LM (%LM; LM/(BMC+FM+LM) × 100%) were calculated. Osteopenia or osteoporosis was identified using the criteria and T-score of the World Health Organization.

Results

Although there were no significant differences in BMI among the age groups, there was a significant decline in height and weight according to age (p < 0.0001 and p = 0.0002, respectively). The LMI and FFMI also declined with age (both p < 0.0001) whereas the FMI exhibited a significant increase that peaked in the 80-89-years group (p = 0.0145). Although the absolute values of BMC and LM declined with age (p = 0.0031 and p < 0.0001, respectively), there was no significant difference in FM. In terms of body composition, there were no significant differences in %BMC but there was an increase in %FM (p < 0.0001) and a decrease in %LM (p < 0.0001) with age. The femoral neck and total hip BMD significantly declined with age (p < 0.0001 and p = 0.0027, respectively) but there were no differences in L1-L4. BMD increased at all sites (all p < 0.01) as BMI increased but there were declines in the detection rates of osteoporosis and osteopenia (both p < 0.001). A logistic regression revealed that when the medium weight group was given a BMI value of 1, a decline in BMI was an independent risk factor of osteoporosis or osteopenia, while an increase in BMI was a protective factor for BMD. At the same time, BMD in L1-L4 exhibited a significant positive association with FMI (p = 0.0003) and the femoral neck and total hip BMDs had significant positive associations with FFMI and LMI, respectively (both p < 0.0001).

Conclusions

These data indicate that LMI and FFMI exhibited significant negative associations with aging in Chinese Han males older than 50 years, whereas FMI had a positive association. BMD in the femoral neck and total hip declined with age but an increased BMI was protective for BMD. LMI and FFMI were protective for BMD in the femoral neck and total hip.     

Urinary Phthalate Metabolites Are Associated with Body Mass Index and Waist Circumference in Chinese School Children

Background

Lab studies have suggested that ubiquitous phthalate exposures are related to obesity, but relevant epidemiological studies are scarce, especially for children.

Objective

To investigate the association of phthalate exposures with body mass index (BMI) and waist circumference (WC) in Chinese school children.

Methods

A cross-sectional study was conducted in three primary and three middle schools randomly selected from Changning District of Shanghai City of China in 2011–2012. According to the physical examination data in October, 2011, 124 normal weight, 53 overweight, and 82 obese students 8–15 years of age were randomly chosen from these schools on the basis of BMI-based age- and sex-specific criterion. First morning urine was collected in January, 2012, and fourteen urine phthalate metabolites (free plus conjugated) were determined by ultra-performance liquid chromatography coupled to tandem mass spectrometry. Multiple linear regression was used to explore the associations between naturally log-transformed urine phthalate metabolites and BMI or WC.

Results

The urine specific gravity-corrected concentrations of nine urine phthalate metabolites and five molar sums were positively associated with BMI or WC in Chinese school children after adjustment for age and sex. However, when other urine phthalate metabolites were included in the models together with age and sex as covariables, most of these significant associations disappeared except for mono (2-ethylhexyl) phthalate (MEHP) and monoethyl phthalate (MEP). Additionally, some associations showed sex- or age-specific differences.

Conclusions

Some phthalate exposures were associated with BMI or WC in Chinese school children. Given the cross-sectional nature of this study and lack of some important obesity-related covariables, further studies are needed to confirm the associations.     

Body Mass Index Is Associated with Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

Background

Prior work suggested that patients with inflammatory bowel diseases (IBD) have lower body mass index (BMI) than controls and patients with lower BMI have more serious complications.

Goal

The study was aimed to find relationship between BMI in patients with and without IBD, investigate effects of medicine therapy and disease stages on patients’ BMI.

Methods

Potentially eligible studies were identified through searching PubMed, Cochrane and Embase databases. Outcome measurements of mean BMI and the number of patients from each study were pooled by a random-effect model. Publication bias test, sensitivity analysis and subgroup analysis were conducted.

Results

A total of 24 studies containing 1442 patients and 2059 controls were included. Main results were as follows: (1) BMI in Crohn’s disease (CD) patients was lower than that in health controls (-1.88, 95% CI -2.77 to -1.00, P< 0.001); (2) Medical therapy significantly improved BMI of CD patients (with therapy: -1.58, -3.33 to 0.16; without: -2.09, 95% CI -3.21 to -0.98) while on the contrary not significantly improving BMI of UC patients (with therapy: -0.24, 95% CI -3.68 to 3.20; without: -1.34, 95% CI -2.87 to 0.20, P = 0.57); (3) Both CD and UC patients in active phase showed significantly greater BMI difference compared with controls than those in remission (CD patients: remission: -2.25, 95% CI -3.38 to -1.11; active phase: -4.25, 95% CI -5.58 to -2.92, P = 0.03; UC patients: remission: 0.4, 95% CI -2.05 to 2.84; active phase: -5.38, -6.78 to -3.97, P = 0.001).

Conclusions

BMI is lower in CD patients; medical therapy couldn’t improve BMI of IBD patients; the state of disease affects BMI of CD patients and UC patients.     

Work‐Related Physical Activity Is Not Associated with Body Mass Index and Obesity

Objective: To analyze the association of work‐related physical activity (WRPA) and leisure‐time physical activity (LTPA) with body mass index (BMI) and obesity in the Spanish adult population aged 20 to 60 years. Research Methods and Procedures: The data were taken from the 1993 Spanish National Health Survey. We analyzed a sample of 12,044 men and women representative of the Spanish population aged 20 to 60 years. BMI and frequency of obesity (BMI ≥ 30 kg/m²) were obtained from self‐reported weight and height. Multiple linear regression and logistic regression models were constructed, adjusting for the main confounding factors. WRPA and LTPA were measured by two questions to classify subjects into four categories of physical activity. Results: Neither mean BMI nor percentage of obesity varied significantly (p > 0.05) by WRPA. Mean BMI was significantly higher (p < 0.01) in those who were inactive in their leisure time (25.90 kg/m² in men and 24.43 kg/m² in women) than in those who reported vigorous activity (24.42 kg/m² and 22.97 kg/m² in men and women, respectively). The odds ration (OR) for obesity decreased with increasing level of LTPA in both men (OR of 0.64 for vigorous activity) and women (OR = 0.68), showing a statistically significant dose‐response relation in both men (for linear trend, p = 0.0021) and women (p = 0.0245). Discussion: These results raise questions about the association between WRPA and obesity and suggest the need to reexamine models of the obesity epidemic that point to automation of the workplace as one of the major explanatory factors.     

Whole-Genome Pathway Analysis on 132,497 Individuals Identifies Novel Gene-Sets Associated with Body Mass Index

Whole genome pathway analysis is a powerful tool for the exploration of the combined effects of gene-sets within biological pathways. This study applied Interval Based Enrichment Analysis (INRICH) to perform whole-genome pathway analysis of body-mass index (BMI). We used a discovery set composed of summary statistics from a meta-analysis of 123,865 subjects performed by the GIANT Consortium, and an independent sample of 8,632 subjects to assess replication of significant pathways. We examined SNPs within nominally significant pathways using linear mixed models to estimate their contribution to overall BMI heritability. Six pathways replicated as having significant enrichment for association after correcting for multiple testing, including the previously unknown relationships between BMI and the Reactome regulation of ornithine decarboxylase pathway, the KEGG lysosome pathway, and the Reactome stabilization of P53 pathway. Two non-overlapping sets of genes emerged from the six significant pathways. The clustering of shared genes based on previously identified protein-protein interactions listed in PubMed and OMIM supported the relatively independent biological effects of these two gene-sets. We estimate that the SNPs located in examined pathways explain ∼20% of the heritability for BMI that is tagged by common SNPs (3.35% of the 16.93% total).     

Arterial Blood Pressure and Modernization in Brazil

The relationship between individual modernization and elevated arterial blood pressure was examined in a study in urban Brazil. We hypothesized that elevated blood pressure would result from the discrepancy between an individual's style of life and his or her economic resources; specifically, we suggested that when modern life-style acquisition exceeded economic resources, a circumstance referred to as "life-style stress," blood pressure would be elevated. This factor was related to diastolic, but not systolic, blood pressure, independently of a variety of biologic, dietary, and sociocultural confounding factors. The perceived change associated with life events also predicted diastolic, but not systolic, blood pressure. Other predictors of diastolic blood pressure were calcium intake, fat intake, race, age, and the body mass index. We argue that sociocultural risk factors emerge in the modernization process as a result of social structural imbalances generated by economic development and represent independent risk factors for elevated arterial blood pressure.     

Ocular Hypertension: General Characteristics and Estimated Cerebrospinal Fluid Pressure. The Beijing Eye Study 2011

Purpose

To examine characteristics of ocular hypertensive subjects and potential associations with estimated cerebrospinal fluid pressure (estCSFP).

Methods

The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years. Ocular hypertension was defined as intraocular pressure (IOP) >21 mmHg, normal optic nerve head appearance and normal retinal nerve fiber layer thickness. IOP was corrected for its dependence on central corneal thickness (CCT) and corneal curvature radius. Estimated CSFP was calculated as CSFP [mmHg] = 0.44×Body Mass Index [kg/m²]+0.16×Diastolic Blood Pressure [mmHg]−0.18×Age [Years]−1.91. Estimated trans-lamina cribrosa pressure difference (estTLCPD) was IOP–estCSFP.

Results

EstCSFP (10.5±3.6 mmHg versus 9.0±3.7 mmHg; P = 0.003) and estTLCPD (12.0±4.4 mmHg versus 5.4±3.8 mmHg; P<0.001) were higher in the ocular hypertensive group than in the normotensive group. In binary regression analysis, ocular hypertension was associated with increased estCSFP (P = 0.03; odds ratio (OR): 1.08; 95% confidence interval (CI): 1.01, 1.17) after adjusting for prevalence of arterial hypertension (P = 0.07; OR: 1.79; 95%CI: 0.96, 3.34), retinal nerve fiber layer thickness (P = 0.03; OR: 0.97; 95%CI: 0.95, 0.997) and blood glucose concentration (P = 0.006; OR: 1.17; 95%CI: 1.04, 1.30).

Conclusions

Ocular hypertensive subjects (with IOP correction for CCT and corneal curvature) as compared to ocular normotensive subjects had a significantly higher estCSFP in univariate analysis and in multivariate analysis. Despite of a higher estCSFP, estTLCPD was still markedly higher in ocular hypertensive eyes than in ocular normotensive eyes.