Body mass, vitamin D and alcohol intake, lactose intolerance, and television watching influence bone mineral density of young, healthy Canadian women

Association between sedentary behavior and bone mass, microstructure and strength in children, adolescents and young adults: a systematic review

Sedentary behavior (SED) research is currently receiving increasing attention in the field of public health. While it has been shown to have negative effects on cardiovascular or metabolic health, there is limited knowledge regarding the relationship between SED and bone health in children, adolescents, and young adults. Thus, the purpose of this review is to investigate the associations between SED and bone health status, specifically bone mass, microstructure, and strength. A comprehensive literature search was conducted across five electronic databases, including EMBASE, PubMed, Medline, Cochrane, Web of Science and CNKI. The inclusion criteria were as follows: healthy participants aged 24 years or younger, with measured SED and measured bone outcomes. The quality of the included articles was assessed using the National Institute of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. After excluding, the final sample included 25 cross-sectional, 9 observational and 2 both cross-sectional and longitudinal studies. Among these, seven were rated as 'high quality', twenty-three were rated as 'moderated quality', and six were rated as 'low quality' according to the quality assessment criteria. After summarizing the evidence, we found no strong evidence to support an association between BMC or BMD and SED, even when considering gender or adjusting for moderate-to-vigorous physical activity (MVPA). However, a strong level of evidence was found indicating a negative relationship between objectively measured SED and cortical bone mineral density (Ct.BMD) in the tibia or stiffness index (SI) in the Calcaneus across all age groups. While the association between adverse bone health outcomes and SED still cannot be confirmed due to insufficient evidence, these findings suggest that bone microstructure and strength may be more sensitive to SED than bone mass. Thus, further evidence is needed to fully understand the connection between sedentary behavior and bone health, particularly regarding the relationship between SED and bone strength.

Vitamin D Levels and Bone Mineral Density in Premenopausal Women Compared to Postmenopausal Women: A Multi-Centre Study From Pakistan

Introduction Despite the sunny climate, women in Pakistan are prone to vitamin D deficiency and subsequent low bone mineral density. The current study explores the extent of this deficiency in both pre- and postmenopausal women in our setting.  Methodology A cross-sectional study was conducted at the outpatient departments of Lady Reading Hospital and Hayatabad Medical Complex Peshawar, Pakistan during the time period between March 2018 and June 2019. Hundred premenopausal women (control group) and 100 postmenopausal women (study group) were inducted in the study. Serum vitamin D levels were determined in patients with suspected vitamin D deficiency. Bone mineral density (BMD) was determined for each patient and the cost of each scan was afforded by our department. A dual-energy x-ray absorptiometry (DEXA) scan was used to perform the bone mineral density assessment. The data was analyzed using Statistical Package for Social Sciences (SPSS) version 26 (IBM, Chicago, IL). Results Serum 25OHD concentration in postmenopausal women was significantly lower compared to premenopausal women (p<0.001). In the study group, 36.0% of women had a severe deficiency of serum vitamin D levels, whereas, in the control group, only two women suffered from severe deficiency of vitamin D. Similarly, bone mineral density was also significantly correlated with the menopausal status of the women (p<0001). It was found that three-fifths of the postmenopausal women had a low bone density. Twenty-four percent of postmenopausal women had very low BMD. In comparison, only a single premenopausal woman was found to have a Z-score of below -2.0. Conclusion The current study highlights the impact of menopause on vitamin D levels and BMD. In our study, we found a significant difference between vitamin D levels and BMD in women of reproductive age compared to postmenopausal women.

Bone-Loading Physical Activity and Alcohol Intake but not BMI Affect Areal Bone Mineral Density in Young College-Aged Korean Women: A Cross-Sectional Study

The purpose of this cross-sectional study was to determine the differences in areal bone mineral density (aBMD) based on alcohol consumption behaviors, bone-loading history as assessed by a bone-specific physical activity questionnaire (BPAQ), and the body mass index (BMI). College-aged female students (N = 112) were recruited from the universities in Seoul and Gyeonggi province, South Korea. The aBMD of the lumbar spine and non-dominant side of the proximal femur (total hip, TH; femoral neck, FN; femoral trochanter, FT) were measured using dual energy X-ray absorptiometry (DXA). Alcohol consumption was determined by the frequency and amount of alcohol intake during the past 12 months using a self-reported questionnaire. The X-scan plus II was used to measure height (cm), body mass (kg), fat-free mass (FFM, kg), and % body fat. Drinking two or more times alcohol per week was associated with greater aBMD of the TH (p = 0.04–0.002) and FN (p = 0.043) compared to a lower frequency of alcohol consumption and 2–4 times per month, respectively. Based on the drinking amount per occasion, there were no significant group differences (p > 0.05) in aBMD at any of the sites. The highest group of total BPAQ had greater aBMD of the TH, FN, and FT versus the lowest (p = 0.023–0.009) and mid of total BPAQ groups (p = 0.004–0.009). Additionally, the highest group had greater aBMD of the lumbar spine compared to the mid group (p = 0.001). No significant group differences in aBMD at any of the sites were noted based on the BMI (p > 0.05). Young college-aged women with greater bone-loading physical activity showed greater aBMD at the TH, FN, FT, and lumbar spine, while a moderate alcohol intake was associated with greater aBMD of the TH and FN. These findings have clinical implications for young women who may not participate in high-impact physical activity and are binge drinkers.

Correlates of sedentary behaviour in university students: A systematic review

High levels of sedentary behaviour are associated with negative health-related outcomes. However, there is limited evidence on the variables influencing sedentary behaviour in university students. The aim of this systematic review was to identify the intrapersonal, interpersonal, environmental, and time correlates of sedentary behaviour in university students. Records from 12 electronic databases were screened by two independent reviewers. Inclusion criteria included: (i) peer-reviewed articles written in English, Spanish, or French; (ii) studies including undergraduate or postgraduate university students; (iii) studies reporting on the association between sedentary behaviour and at least one variable. The protocol is registered in PROSPERO (CRD42017074198). A total of 126 studies published between 1994 and 2017 met the inclusion criteria. The primary measure of sedentary behaviour was self-reported screen time (61%), followed by total sitting time (28%). Most studies were cross-sectional (86%). After excluding high risk of bias studies (58%), only three intrapersonal variables were sufficiently investigated (≥4) to determine an association with sedentary behaviour: physical activity (negative association with sitting time), obesity markers (indeterminate associations with TV viewing), and gender - female (null associations with total sitting time and screen time). Overall, most of the reported correlates of sedentary behaviour were intrapersonal, non-modifiable factors. Further research on modifiable correlates covering all socio-ecologic levels is required to inform future intervention development. In addition, longitudinal studies are needed to enable the identification of determinants. Improvements in designing and reporting future studies are recommended to help strengthen the available evidence and facilitate future reviewing efforts.

Vitamin D Intake among Premenopausal Women Living in Jeddah: Food Sources and Relationship to Demographic Factors and Bone Health

BACKGROUND

Saudi women depend on food sources to maintain their serum 25(OH) D concentrations because covering by traditional clothing and time spent indoors limit their sun exposure. Little is known about vitamin D intake and its main food sources in Saudi Arabia. In addition, the association between vitamin D and calcium intake and bone mineral density (BMD) in young women is not well researched.

OBJECTIVES

To assess the adequacy of vitamin D intake among Saudi women as compared to the estimated average requirements (EARs), to identify dietary vitamin D sources, to examine potential determinants of vitamin D intake, and to assess bone health and the association of calcium and vitamin D intake with BMD.

METHODS

This cross-sectional study was conducted in 257 premenopausal women aged 20-50 years in Jeddah, Saudi Arabia. Dietary vitamin D and calcium were assessed by the Semiquantitative Food Frequency Questionnaire. BMD was measured using dual-energy X-ray absorptiometry (DXA) in a subset of women (n=102) at the lumbar spine and femur neck.

RESULTS

Sixty-five percent of women were below the EAR for vitamin D, and 61% fell below the EAR for calcium. Dairy products, supplements, and fish contributed most to vitamin D intake. Increased age was an independent determinant of sufficient vitamin D intake (p < 0.001). The prevalence of osteopenia was 33% in the lumbar spine and 30% in the femur neck. There was a significant positive association between calcium intake and BMD at the lumbar spine (p=0.043) after controlling for body mass index and energy intake. Vitamin D intake was not significantly different between women with low and normal bone mass.

CONCLUSION

Premenopausal women in Jeddah have insufficient vitamin D and calcium intakes. Public health strategies to improve nutrition in young women are needed, and expanding fortification programs to include all dairy products would be useful.

Bivariate genome-wide association analyses identified genetic pleiotropic effects for bone mineral density and alcohol drinking in Caucasians

Several studies indicated bone mineral density (BMD) and alcohol intake might share common genetic factors. The study aimed to explore potential SNPs/genes related to both phenotypes in US Caucasians at the genome-wide level. A bivariate genome-wide association study (GWAS) was performed in 2069 unrelated participants. Regular drinking was graded as 1, 2, 3, 4, 5, or 6, representing drinking alcohol never, less than once, once or twice, three to six times, seven to ten times, or more than ten times per week respectively. Hip, spine, and whole body BMDs were measured. The bivariate GWAS was conducted on the basis of a bivariate linear regression model. Sex-stratified association analyses were performed in the male and female subgroups. In males, the most significant association signal was detected in SNP rs685395 in DYNC2H1 with bivariate spine BMD and alcohol drinking (P = 1.94 × 10^-8). SNP rs685395 and five other SNPs, rs657752, rs614902, rs682851, rs626330, and rs689295, located in the same haplotype block in DYNC2H1 were the top ten most significant SNPs in the bivariate GWAS in males. Additionally, two SNPs in GRIK4 in males and three SNPs in OPRM1 in females were suggestively associated with BMDs (of the hip, spine, and whole body) and alcohol drinking. Nine SNPs in IL1RN were only suggestively associated with female whole body BMD and alcohol drinking. Our study indicated that DYNC2H1 may contribute to the genetic mechanisms of both spine BMD and alcohol drinking in male Caucasians. Moreover, our study suggested potential pleiotropic roles of OPRM1 and IL1RN in females and GRIK4 in males underlying variation of both BMD and alcohol drinking.

Self-Report Dietary Assessment Tools Used in Canadian Research: A Scoping Review

Choosing the most appropriate dietary assessment tool for a study can be a challenge. Through a scoping review, we characterized self-report tools used to assess diet in Canada to identify patterns in tool use and to inform strategies to strengthen nutrition research. The research databases Medline, PubMed, PsycINFO, and CINAHL were used to identify Canadian studies published from 2009 to 2014 that included a self-report assessment of dietary intake. The search elicited 2358 records that were screened to identify those that reported on self-report dietary intake among nonclinical, non-Aboriginal adult populations. A pool of 189 articles (reflecting 92 studies) was examined in-depth to assess the dietary assessment tools used. Food-frequency questionnaires (FFQs) and screeners were used in 64% of studies, whereas food records and 24-h recalls were used in 18% and 14% of studies, respectively. Three studies (3%) used a single question to assess diet, and for 3 studies the tool used was not clear. A variety of distinct FFQs and screeners, including those developed and/or adapted for use in Canada and those developed elsewhere, were used. Some tools were reported to have been evaluated previously in terms of validity or reliability, but details of psychometric testing were often lacking. Energy and fat were the most commonly studied, reported by 42% and 39% of studies, respectively. For ∼20% of studies, dietary data were used to assess dietary quality or patterns, whereas close to half assessed ≤5 dietary components. A variety of dietary assessment tools are used in Canadian research. Strategies to improve the application of current evidence on best practices in dietary assessment have the potential to support a stronger and more cohesive literature on diet and health. Such strategies could benefit from national and global collaboration.

The management of lactose intolerance among primary care physicians and its correlation with management by gastroenterologists: the SEPD-SEMG national survey

INTRODUCTION AND AIMS

The understanding of lactose intolerance (LI) is limited in some professional settings. Sociedad Española de Patología Digestiva (SEPD) and Sociedad Española de Medicina General (SEMG) have developed a survey in order to: a) Analyze primary care physicians (PCPs) knowledge and clinical management; and b) to compare results with those of a previous survey of Spanish gastroenterologists (GEs).

MATERIAL AND METHODS

An online questionnaire was sent to SEMG members with 27 items on various issues: Demographics, occupational characteristics, outlook on LI, diagnostic tests, treatment, and follow-up. Results were compared to those from a survey of GEs.

RESULTS

A total of 456 PCPs responded, versus 477 GEs. PCPs had an older mean age and longer professional experience. Level of understanding of LI was similar, albeit a higher proportion of PCPs lacked epidemiological awareness (p < 0.01). GEs tended to consider LI a "minor" condition (71.3 vs. 40.1%; p > 0.001), and LI symptoms as overlapping those of irritable bowel syndrome (93.5 vs. 88.2%; p = 0.005), although symptoms perceived as suspicious of LI were similar in both groups. Dietary recommendations were recognized as the primary therapeutic approach.

CONCLUSION

This study reveals the outlook of PCPs on LI, and allows comparison with that of GEs, as a basis for the development of strategies aimed at improving LI understanding, approach and management in our setting.

Duration of television viewing and bone mineral density in Chinese women

Studies on the relationship between television (TV) viewing and bone mineral density (BMD) in adults are limited. The purpose of this study was to examine whether longer duration of TV viewing increased the risk of lower BMD in Chinese women. A total of 626 female adults were voluntarily recruited into the study. Anthropometric measurements were obtained using standard procedures. Body composition including total body and regional BMD was estimated using dual-energy X-ray absorptiometry. The duration of TV viewing was categorized into 4 groups: <1 h, 1 to <2 h, 2 to <3 h, and ≥3 h. Multiple linear regression models were applied to analyze the associations between duration of TV viewing and total and regional BMD in all subjects and in subjects stratified by age of 45 years, respectively. After adjusting for age, BMI, alcohol use, smoking, education, income, urbanicity, leisure time physical activity, occupational physical activity, and menopause, the significant trend of pelvic BMD across categories of TV viewing was observed in all subjects (p < 0.05). Further analysis revealed that women aged <45 years, the 1 to <2 h group, the 2 to <3 h group, and the ≥3 h group were significantly associated with lower total body and regional BMD compared to women aged <45 years in the <1 h group. We concluded that the duration of TV viewing was negatively associated with BMD in Chinese women, especially in those aged 18-44 years. It might be sensible to reduce TV viewing time to prevent bone loss in young women.