Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults

Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity.

Associations between health-related fitness and patient-reported symptoms in newly diagnosed breast cancer patients

Background:Newly diagnosed breast cancer patients experience symptoms that may affect their quality of life,treatment outcomes,and survival.Preventing and managing breast cancer-related symptoms soon after diagnosis is essential.The purpose of this study was to investigate the associations between health-related fitness(HRF)and patient-reported symptoms in newly diagnosed breast cancer patients.Methods:This study utilized baseline data from the Alberta Moving Beyond Breast Cancer Cohort Study that were collected within 90 days of diagnosis.HRF measures included peak cardiopulmonary fitness(peak volume of oxygen consumption(VO_(2peak))),maximal muscular strength and endurance,flexibility,and body composition.Symptom measures included depression,sleep quality,and fatigue.Adjusted multivariable logistic regression was performed for analyses.Results:Of 1458 participants,51.5%reported poor sleep quality,26.5%reported significant fatigue,and 10.4%reported moderate depression.In multivariable-adjusted models,lower relative VO_(2peak)was independently associated with a greater likelihood of all symptom measures,including moderate depression(p<0.001),poor sleep quality(p=0.009),significant fatigue(p=0.008),any symptom(p<0.001),and multiple symptoms(p<0.001).VO_(2peak)demonstrated threshold associations with all symptom measures such that all 3 lower quartiles exhibited similar elevated risk compared to the highest quartile.The strength of the threshold associations varied by the symptom measure with odds ratios ranging from-1.5 for poor sleep quality to-3.0 for moderate depression and multiple symptoms.Moreover,lower relative upper body muscular endurance was also independently associated with fatigue in a dose-response manner(p=0.001),and higher body weight was independently associated with poor sleep quality in an inverted U pattern(p=0.021).Conclusion:Relative VO_(2peak)appears to be a critical HRF component associated with multiple patient-reported symptoms in newly diagnosed breast cancer patients.Other HRF parameters may also be important for specific symptoms.Exercise interventions targeting different HRF components may help newly diagnosed breast cancer patients manage specific symptoms and improve outcomes.

Handgrip strength and health outcomes: Umbrella review of systematic reviews with meta-analyses of observational studies

Purpose:The aim of the present study was to assess both the credibility and strength of evidence arising from systematic reviews with meta-analyses of observational studies on handgrip strength and health outcomes.Methods:An umbrella review of systematic reviews with meta-analyses of observational studies was conducted.We assessed meta-analyses of observational studies based on random-effect summary effect sizes and their p values,95%prediction intervals,heterogeneity,small-study effects,and excess significance.We graded the evidence from convincing(Class I)to weak(Class IV).Results:From 504 articles returned in a search of the literature,8 systematic reviews were included in our review,with a total of 11 outcomes.Overall,nine of the 11 of the outcomes reported nominally significant summary results(p<0.05),with 4 associations surviving the application of the more stringent p value(p<106).No outcome presented convincing evidence.Three associations showed Class II evidence(i.e.,highly suggestive):(1)higher handgrip values at baseline were associated with a minor reduction in mortality risk in the general population(n=34 studies;sample size=1,855,817;relative risk=0.72,95%confidence interval(95%CI):0.670.78),(2)cardiovascular death risk in mixed populations(n=15 studies;relative risk=0.84,95%CI:0.780.91),and(3)incidence of disability(n=7 studies;relative risk=0.76,95%CI:0.660.87).Conclusion:The present results show that handgrip strength is a useful indicator for general health status and specifically for early all-cause and cardiovascular mortality,as well as disability.To further inform intervention strategies,future research is now required to fully understand mechanisms linking handgrip strength scores to these health outcomes.

Accuracy of baseline low-dose computed tomography lung cancer screening: a systematic review and meta-analysis

Background:Screening using low-dose computed tomography(LDCT)is a more effective approach and has the potential to detect lung cancer more accurately.We aimed to conduct a meta-analysis to estimate the accuracy of population-based screening studies primarily assessing baseline LDCT screening for lung cancer.Methods:MEDLINE,Excerpta Medica Database,and Web of Science were searched for articles published up to April 10,2022.According to the inclusion and exclusion criteria,the data of true positives,false-positives,false negatives,and true negatives in the screening test were extracted.Quality Assessment of Diagnostic Accuracy Studies-2 was used to evaluate the quality of the literature.A bivariate random effects model was used to estimate pooled sensitivity and specificity.The area under the curve(AUC)was calculated by using hierarchical summary receiver-operating characteristics analysis.Heterogeneity between studies was measured using the Higgins I 2 statistic,and publication bias was evaluated using a Deeks’funnel plot and linear regression test.Results:A total of 49 studies with 157,762 individuals were identified for the final qualitative synthesis;most of them were from Europe and America(38 studies),ten were from Asia,and one was from Oceania.The recruitment period was 1992 to 2018,and most of the subjects were 40 to 75 years old.The analysis showed that the AUC of lung cancer screening by LDCT was 0.98(95%CI:0.96-0.99),and the overall sensitivity and specificity were 0.97(95%CI:0.94-0.98)and 0.87(95%CI:0.82-0.91),respectively.The funnel plot and test results showed that there was no significant publication bias among the included studies.Conclusions:Baseline LDCT has high sensitivity and specificity as a screening technique for lung cancer.However,long-term follow-up of the whole study population(including those with a negative baseline screening result)should be performed to enhance the accuracy of LDCT screening.

Differences in transportation and leisure physical activity by neighborhood design controlling for residential choice

Background:Cross-sectional studies provide useful insight about the associations between the built environment and physical activity(PA),particularly when reasons for neighborhood choice are considered.Our study analyzed the relationship between levels of weekly transportation and leisure PA among 3 neighborhood designs,statistically adjusting for sociodemographic characteristics and reasons for neighborhood choice.Methods:A stratified random sample of adults(age>20 years)living in Calgary(Canada)neighborhoods with different neighborhood designs(grid,warped-grid,and curvilinear)and socioeconomic status completed a self-administered questionnaire capturing PA,sociodemographic characteristics,and reasons for neighborhood choice(response rate=10.1%;n=1023).Generalized linear models estimated associations between neighborhood design and transportation and leisure PA outcomes(participation(any vs.none)and volume(metabolic equivalent:h/week)),adjusting for neighborhood socioeconomic status,sociodemographic characteristics(gender,age,ethnicity,education,household income,marital status,children,vehicle access,dog ownership,and injury),and reasons for neighborhood choice(e.g.,proximity and quality of recreational and utilitarian destinations,proximity to work,highway access,aesthetics,and sense of community).Results:Overall,854 participants had resided in their neighborhood for at least 12 months and provided complete data.Compared with those living in curvilinear neighborhoods,grid neighborhood participants had greater odds(p<0.05)of participating in any transportation walking(odds ratio(OR)=2.17),transportation and leisure cycling(OR=2.39 and OR=1.70),active transportation(OR=2.16),and high-intensity leisure PA(≥6 metabolic equivalent;OR=1.74),respectively.There were no neighborhood differences in the volume of any transportation or leisure PA undertaken.Adjustment for neighborhood selection had minimal impact on the statistical or practical importance of model estimates.Conclusion:Neighborhood design is associated with PA patterns in adults,independent of reasons for neighborhood choice and sociodemogranhic factors.

Outcome measures of phase III anticancer drug trials in China

To the Editor:Phase III clinical trials have been used to provide evidence in support of the approval of most new agents in the treatment of cancer.[1]The selection of the primary endpoint is critical to the outcome of phase III clinical trials and the launch of the cancer drug.In the present study,we performed a crosssectional study to describe the endpoint information and analyze the trends over time in the research and development of cancer drugs tested in phase III clinical trials in China.

中国人群伤残权重测量:聚焦癌症,量化评估伤残权重对癌症疾病负担估计的影响

伤残权重对于量化评估非死亡相关健康损失至关重要.全球范围看,目前仅有少数国家或地区对伤残权重进行了评估,且极少有肿瘤特异性的伤残权重结果报道.本研究基于大样本人群估计中国人群肿瘤特异性伤残权重,并比较不同伤残权重对量化评估肿瘤疾病负担的影响.基于开放式网络调查,采用配对比较的方法进行伤残权重的测量.伤残寿命损失年(YLDs)估计为不同瘤种各时期肿瘤的患病人数与其对应时期的伤残权重乘积之和.研究共收集到44,069份有效调查问卷,估计了包含18类恶性肿瘤在内的254个健康状态的残疾权重.其中,诊断和初始治疗阶段的肿瘤特异性伤残权差异较大,脑瘤的伤残权重最高为0.619(95%不确定性区间(UI):0.606~0.632),口咽癌伤残权重最低,为0.167(95%UI:0.158~0.176).不同肿瘤伤残权重对YLDs估计影响较大,所有肿瘤合计的YLDs差异超过30%.本研究提供的肿瘤特异性伤残权重可以为精确估计肿瘤疾病负担提供重要的数据支持.