Consumption of Fish and ω-3 Fatty Acids and Cancer Risk: An Umbrella Review of Meta-Analyses of Observational Studies.

Multiple studies have suggested that ω-3 fatty acid intake may have a protective effect on cancer risk; however, its true association with cancer risk remains controversial. We performed an umbrella review of meta-analyses to summarize and evaluate the evidence for the association between ω-3 fatty acid intake and cancer outcomes. We searched PubMed, Embase, and the Cochrane Database of Systematic Reviews from inception to December 1, 2018. We included meta-analyses of observational studies that examined associations between intake of fish or ω-3 fatty acid and cancer risk (gastrointestinal, liver, breast, gynecologic, prostate, brain, lung, and skin) and determined the level of evidence of associations. In addition, we appraised the quality of the evidence of significant meta-analyses by using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. We initially screened 598 articles, and 15 articles, including 57 meta-analyses, were eligible. Among 57 meta-analyses, 15 reported statistically significant results. We found that 12 meta-analyses showed weak evidence of an association between ω-3 fatty acid intake and risk of the following types of cancer: liver cancer (n = 4 of 6), breast cancer (n = 3 of 14), prostate cancer (n = 3 of 11), and brain tumor (n = 2 of 2). In the other 3 meta-analyses, studies of endometrial cancer and skin cancer, there were no assessable data for determining the evidence levels. No meta-analysis showed convincing, highly suggestive, or suggestive evidence of an association. In the sensitivity analysis of meta-analyses by study design, we found weak associations between ω-3 fatty acid intake and breast cancer risk in cohort studies, but no statistically significant association in case-control studies. However, the opposite results were found in case of brain tumor risk. Although ω-3 fatty acids have been studied in several meta-analyses with regard to a wide range of cancer outcomes, only weak associations were identified in some cancer types, with several limitations. Considering the nonsignificant or weak evidence level, clinicians and researchers should cautiously interpret reported associations between ω-3 fatty acid consumption and cancer risks.

Hyperprogressive Disease during Anti-PD-1 (PDCD1) / PD-L1 (CD274) Therapy: A Systematic Review and Meta-Analysis.

Hyperprogressive disease (HPD) is a recently acknowledged pattern of rapid tumor progression after the initiation of immune checkpoint inhibitors. HPD has been observed across various types of tumors and has been associated with poor survival. We performed a meta-analysis to identify baseline (i.e., prior to programmed cell death 1 [PD-1, PDCD1] / programmed cell death 1 ligand 1 [PD-L1, CD274] inhibitor therapy) patient factors associated with risks of developing HPD during PD-1/PD-L1 inhibitor therapy. We searched eight databases until 6 June 2019. We calculated the summary odds ratio (OR) and its 95% confidence interval (CI) using the random-effects model and explored between-study heterogeneity and small-study effects. A total of nine articles was eligible (217 HPD cases, 1519 cancer patients) for meta-analysis. There was no standard definition of HPD, and the incidence of HPD ranged from 1 to 30%. We identified twenty-three baseline patient factors, of which five factors were statistically significantly associated with HPD. These were serum lactate dehydrogenase (LDH) above the upper normal limit (OR = 1.89, 95% CI = 1.02-3.49, p = 0.043), more than two metastatic sites (OR = 1.86, 1.34-2.57, p < 0.001), liver metastases (OR = 3.33, 2.07-5.34, p < 0.001), Royal Marsden Hospital prognostic score of 2 or above (OR = 3.33, 1.96-5.66, p < 0.001), and positive PD-L1 expression status that was inversely correlated with HPD (OR = 0.60, 0.36-0.99, p = 0.044). Between-study heterogeneity was low. Evidence of small-study effect was found in one association (PD-L1 expression). Subset analyses of patients with non-small cell lung cancer showed similar results. Future studies are warranted to identify underlying molecular mechanisms and to test their roles as predictive biomarkers of HPD.

Association of type and intensity of physical activity with plasma biomarkers of inflammation and insulin response.

Several biological mechanisms linking physical activity with cancer have been proposed. However, the influence of specific components of physical activity (volume, type and intensity), and their interaction with adiposity and diet, on cancer-related biomarkers remain unclear. We used cross-sectional data on 7,219 men in the Health Professionals Follow-up Study (1992-1994) with C-reactive protein (CRP), interleukin-6 (IL6), tumor necrosis factor alpha receptor 2 (TNFαR2), adiponectin, C-peptide and triglycerides/high-density lipoprotein cholesterol ratio (TG/HDL). Details on physical activity, diet and adiposity were assessed by questionnaires. We used multivariable-adjusted linear regression analyses to estimate relative concentrations of biomarkers by physical activity. Total physical activity was favorably associated with all biomarkers in a fairly linear manner. Comparing the highest (63+ metabolic equivalent (MET)-hr/week) to the lowest (0-8.9 MET-hr/week) physical activity groups, the percent relative difference in concentration of biomarkers was -31% for CRP, -22% for IL6, -8% for TNFαR2, +9% for adiponectin, -22% for C-peptide, and -20% for TG/HDL. These differences were modestly attenuated after adjustment for adiposity. For the same total MET-hours of physical activity, the association was stronger for men engaging in both aerobic and resistance exercises compared to those engaging in aerobic only. However, no difference was found between those engaging in vigorous activities (≥20% of total MET-hours) compared to those who did smaller amount of vigorous activities. Physical activity showed similar associations for these biomarkers regardless of adiposity and dietary pattern. In conclusion, high physical activity, preferably aerobic plus resistance training, was associated with favorable cancer-related biomarkers.

Resting heart rate and risk of type 2 diabetes: A prospective cohort study and meta-analysis.

BACKGROUND: Positive association between resting heart rate (RHR) and risk of type 2 diabetes (T2D) has been documented in several studies. However, whether RHR is an independent predictor of T2D and its potential interaction with other risk factors of T2D remain unclear. METHODS: We conducted a prospective cohort study of 31 156 men from the Health Professionals Follow-up Study (1992-2012). Cox proportional hazard model was used to examine the association between RHR and T2D risk. We further examined whether this association is modified by known risk factors. Lastly, we conducted a meta-analysis of prospective cohort studies. RESULTS: During 505 380 person-years of follow-up, we identified 2338 incident T2D cases. The multivariable-adjusted hazard ratio (HR) comparing the highest vs lowest categories of RHR was 1.69 (95% confidence interval [CI], 1.43-2.01). Increase in 10 bpm of RHR was associated with 19% increased risk of T2D in the fully adjusted model (HR, 1.19; 95% CI, 1.14-1.24). The HRs of T2D associated with RHR were stronger among those with normal weight or without hypertension (P interaction < 0.001). Moreover, RHR with other known risk factors cumulatively increased T2D risk. A meta-analysis consistently showed a positive association between RHR and T2D risk (the summary relative risk [RR] for highest vs lowest RHR, 1.53; 95% CI, 1.26-1.86, n = 12, the summary RR per 10 bpm increase, 1.17; 95% CI, 1.09-1.26, n = 13). CONCLUSIONS: High RHR was independently associated with increased risk of T2D. Our findings suggest that RHR, with other known risk factors, could be a useful tool to predict T2D risk.

Correction to: Personal, relational and school factors associated with involvement in fights with weapons among school-age youth in Brazil: a multilevel ecological approach.

The authors would like to include the funding note here which was found missing in the original publication.

Personal, relational and school factors associated with involvement in fights with weapons among school-age youth in Brazil: a multilevel ecological approach.

OBJECTIVES: To investigate the association between personal, relational and school factors with involvement in fights with weapon among Brazilian school-age youth. METHODS: Using data from the Adolescent School-Based Health Survey 2015 (n = 102.072), we conducted multilevel logistic regression models. RESULTS: IFW was associated with female sex (OR = 0.45), and with older age (OR = 1.15), previous involvement in physical violence (OR = 2.05), history of peer verbal (OR = 1.14) and domestic victimization (OR = 2.11), alcohol use (OR = 2.42) and drug use (OR = 3.23). The relational variables (e.g., parent's supervision) were mostly negatively associated with IFW. At the school level, attending public school and attending schools in violent surroundings were both positively associated with IFW. The intraclass correlation coefficient estimated in the empty model showed that 5.77% of the variance of IFW was at school level. When all individual- and school-level variables were included in the model, the proportional changes in variance were 61.7 and 71.55%, respectively. CONCLUSIONS: IFW is associated with personal, relational and school factors. Part of the variance in IFW by school is explained by characteristics of the school context.

Reporting bias in the literature on the associations of health-related behaviors and statins with cardiovascular disease and all-cause mortality.

Reporting bias in the literature occurs when there is selective revealing or suppression of results, influenced by the direction of findings. We assessed the risk of reporting bias in the epidemiological literature on health-related behavior (tobacco, alcohol, diet, physical activity, and sedentary behavior) and cardiovascular disease mortality and all-cause mortality and provided a comparative assessment of reporting bias between health-related behavior and statin (in primary prevention) meta-analyses. We searched Medline, Embase, Cochrane Methodology Register Database, and Web of Science for systematic reviews synthesizing the associations of health-related behavior and statins with cardiovascular disease mortality and all-cause mortality published between 2010 and 2016. Risk of bias in systematic reviews was assessed using the ROBIS tool. Reporting bias in the literature was evaluated via small-study effect and excess significance tests. We included 49 systematic reviews in our study. The majority of these reviews exhibited a high overall risk of bias, with a higher extent in health-related behavior reviews, relative to statins. We reperformed 111 meta-analyses conducted across these reviews, of which 65% had statistically significant results (P < 0.05). Around 22% of health-related behavior meta-analyses showed small-study effect, as compared to none of statin meta-analyses. Physical activity and the smoking research areas had more than 40% of meta-analyses with small-study effect. We found evidence of excess significance in 26% of health-related behavior meta-analyses, as compared to none of statin meta-analyses. Half of the meta-analyses from physical activity, 26% from diet, 18% from sedentary behavior, 14% for smoking, and 12% from alcohol showed evidence of excess significance bias. These biases may be distorting the body of evidence available by providing inaccurate estimates of preventive effects on cardiovascular and all-cause mortality.

Prevalence of active transportation among adults in Latin America and the Caribbean: a systematic review of population-based studies.

OBJECTIVE: To describe the prevalence of "active" (self-propelled, human-powered) transportation in the Latin America and Caribbean (LAC) region over the past decade. METHODS: MEDLINE, Excerpta Medica (Embase), SportDiscus, Lilacs, MediCarib, Web of Science, OVID, CINAHL, Scopus, Google Scholar, National Transportation Library, and TRIS/TRID were searched for articles on active transportation published between January 2003 and December 2014 with (at least) a title and abstract in English, Portuguese, or Spanish. Research was included in the study if the two reviewing authors agreed it 1) was conducted in an adult sample (≥ 18 years old), 2) was designed to be representative of any LAC area, and 3) reported at least one measure of active transportation. Reference lists of included papers and retrieved reviews were also checked. A total of 129 key informants (87 scientific experts and 42 government authorities) were contacted to identify additional candidate publications. Two other authors extracted the data independently. RESULTS: A total of 10 459 unique records were found; the full texts of 143 were reviewed; and a total of 45 studies were included in the study, yielding estimates for 72 LAC settings, most of which were in Argentina, Brazil, and Colombia. No eligible studies were found for the years 2003-2004, resulting in a 10-year study time frame. Estimates were available for walking, cycling, or the combination of both, with a high degree of heterogeneity (heterogeneity index (I2) ≥ 99%). The median prevalence of active transportation (combining walking and cycling) was 12.0%, ranging from 5.1% (in Palmas, Brazil) to 58.9% (in Rio Claro, Brazil). Men cycled more than women in all regions for which information was available. The opposite was true for walking. CONCLUSIONS: Prevalence of active transportation in LAC varied widely, with great heterogeneity and uneven distribution of studies across countries, indicating the need for efforts to build comprehensive surveillance systems with standardized, timely, and detailed estimates of active transportation in order to support policy planning and evaluation.

Physical activity as part of daily living: Moving beyond quantitative recommendations.

The purpose of this study is to discuss a paradigm shift towards a broader understanding of physical activity (PA) as part of daily living and, therefore, a different approach for PA guidelines, research, and promotion. To this aim, we centered the discussion in two topics: 1) PA: from a restricted view to a broader phenomenon; and 2) Recommendations for PA: moving beyond minutes and dose-response. A holistic understanding of PA and its relationship with health is not possible unless it is considered values, meanings, and symbols that impregnate the human behavior linked to the modes of living of a given people. If we do believe that PA is a behavior essential to human life, we must align our actions to our speech. However, current guidelines, as well as in most policies and programs of PA is largely portrayed as a way to attain longer life expectancy and less diseases, which runs against our consolidated understanding of PA as part of our everyday life. New guidelines could focus on how, when, why, where, and with whom we include PA in our daily lives, based on a day-long approach, instead of how much we should do in order to prevent non-communicable diseases.

Food environments in schools and in the immediate vicinity are associated with unhealthy food consumption among Brazilian adolescents.

BACKGROUND: Evidence of the influence of the school food environment on adolescent diet is still little explored in low- and middle-income countries. We aimed to evaluate the association between food environment in schools and the immediate vicinity and the regular consumption of unhealthy food among adolescents. METHODS: We used cross-sectional data collected by the Brazilian National Survey of School Health (PeNSE) from a representative sample of adolescents attending 9th grade public and private schools in Brazil, in 2012. We estimated students' regular consumption (>5days/week) of unhealthy food (soft drinks, bagged salty snacks, deep fried salty snacks and sweets) and school availability, in the cafeteria or an alternative outlet, of the same food plus some healthy options (fruit and natural fruit juice). We performed multilevel logistic regression models. RESULTS: Having a cafeteria inside school selling soft drinks (private schools OR=1.23; 95% CI=1.14-1.33; public schools OR=1.13; 95% CI=1.06-1.20) and deep fried salty snacks (private schools OR=1.41 95% CI=1.26-1.57; public schools OR=1.16 95% CI=1.08-1.24) was associated with a higher consumption of these unhealthy foods of among students. In private schools, cafeteria selling fruit and natural fruit juice was associated with lower student consumption of bagged salty snacks (OR=0.86; 95% CI 0.77-0.96) and soft drinks (OR=0.85; 95% CI=0.76-0.94). In addition, eating meals from the Brazilian School Food Program in public schools was associated with a lower consumption of unhealthy foods. CONCLUSIONS: Foods available in the school food environment are associated with the consumption of unhealthy food among adolescents in Brazil.

Lifestyle among former cancer patients in Brazil in 2013.

People who have been diagnosed with cancer tend to adopt healthier lifestyles. This study analyzes the prevalence of smoking, eating fruits and vegetables, exercise and the use of alcoholic beverages among individuals who reported to have been diagnosed with cancer in the PNS (Pesquisa Nacional de Saúde or National Health Survey). The prevalence and corresponding 95% confidence intervals were calculated for consuming fruits and vegetables, sedentary lifestyle (no exercise), use of alcoholic beverages, being overweight and tobacco use. The associa-tion between having received a diagnosis of cancer and the risk and protection factors was analyzed using a Poisson regression, adjusted by sociodemographic variables and other chronic comorbidities. The analyses were stratified by time since the diagnosis and the type of cancer related to the factors analyzed. The types of cancer most often reported were breast and cervix in women, and prostate and stomach in men. Among those who had cancer diagnoses, there was a higher consumption of fruits and vegetables, higher proportion of ex-smokers, however, increased use of alcohol. There was no difference in the frequency of exercise or incidence of being overweight between the two groups. Measures to promote health and prevent chronic diseases should be implemented in the follow-up of people who have had cancer, in an effort to ensure integrated healthcare.

The Role of School Environment in Physical Activity among Brazilian Adolescents.

OBJECTIVE: To analyze the association of physical activity facilities and extracurricular sports activities in schools with physical activity among adolescents. METHODOLOGY/PRINCIPAL FINDINGS: We used data collected for the National Survey of School Health in 2012. The national representative sample comprised 109,104 Brazilian students from 2,842 schools. We calculated the prevalence of participation in physical education classes, leisure-time physical activity, and total physical activity level. We also evaluated the following physical activity facilities: sports courts, running/athletics tracks, schoolyard with teacher-directed physical activities, swimming pools, locker rooms; and the offer of extracurricular sports activities. Schools with at least one physical activity facility had increased odds of participation in physical education (OR 1.59; 95% CI 1.20 to 2.10). However, in order to increase leisure-time physical activity (OR1.14; 95% CI 1.03 to 1.26) and total physical activity level (OR 1.15; 95% CI 1.06 to 1.24) at least four and two facilities, respectively, were necessary. Extracurricular sports activities in schools were positively associated with leisure-time physical activity and physical activity level. The number of sports courts and swimming pool in a school were associated with participation in physical education classes. Availability of sports courts, running/athletics tracks, and swimming pool in schools were associated with leisure-time physical activity. Total physical activity was associated with schools with sports courts, schoolyard with teacher-directed physical activities, and swimming pool. CONCLUSIONS: School-level characteristics have important potential to increase the possibility of engagement in physical activity in and out of school, and therefore have a fundamental role in promoting these practices.

Dietary intake of Brazilian adolescents.

OBJECTIVE: To analyse the dietary intake of Brazilian adolescents and investigate its association with sociodemographic factors as well as health-risk and health-protective behaviours. DESIGN: Cross-sectional study. SETTING: The study was based on data supplied by the National Survey of Schoolchildren's Health (2012) on sociodemographic factors, dietary intake and health-risk and health-protective behaviours of schoolchildren in Brazil. A nutritional scale was elaborated combining markers of healthy and unhealthy diets. Poisson regression analysis was applied to investigate the association between the sociodemographic factors and regular intake (≥5 times/week) of selected foods; linear regression analysis was applied to investigate the association of sociodemographic and behavioural factors with nutritional scale score. SUBJECTS: A total of 109 104 adolescents attending the ninth year of education at 2842 schools in Brazil. RESULTS: Fewer than 30 % of the adolescents consumed raw or cooked vegetables on a regular basis, whereas more than one-third reported regular intake of sweets, soft drinks and sweet biscuits. Adolescents from the southern area and the oldest ones were those most exposed to inadequate dietary intake. The nutritional scale average score was higher in the students attending public school and exhibited a positive correlation with protective behaviours, such as being physically active, having meals with parents and eating breakfast, and a negative correlation with risk behaviours such as eating while studying or watching television and having smoked, drunk alcohol or used other drugs in the previous 30 d. CONCLUSIONS: The results indicate an association between undesirable nutritional habits and other risk behaviours among Brazilian adolescents.

Effect of physical inactivity on major noncommunicable diseases and life expectancy in Brazil.

BACKGROUND: In Brazil, one-fifth of the population reports not doing any physical activity. This study aimed to assess the impact of physical inactivity on major noncommunicable diseases (NCDs), all-cause mortality and life expectancy in Brazil, by region and sociodemographic profile. METHODS: We estimated the population attributable fraction (PAF) for physical inactivity associated with coronary heart disease, type 2 diabetes, breast cancer, colon cancer, and all-cause mortality. To calculate the PAF, we used the physical inactivity prevalence from the 2008 Brazilian Household Survey and relative risk data in the literature. RESULTS: In Brazil, physical inactivity is attributable to 3% to 5% of all major NCDs and 5.31% of all-cause mortality, ranging from 5.82% in the southeastern region to 2.83% in the southern region. Eliminating physical inactivity would increase the life expectancy by an average of 0.31 years. This reduction would affect mainly individuals with ≥ 15 years of schooling, male, Asian, elderly, residing in an urban area and earning ≥ 2 times the national minimum wage. CONCLUSIONS: In Brazil, physical inactivity has a major impact on NCDs and mortality, principally in the southeastern and central-west regions. Public policies and interventions promoting physical activity will significantly improve the health of the population.

Sedentary behavior and health outcomes: an overview of systematic reviews.

OBJECTIVE: 1) To synthesize the current observational evidence for the association between sedentary behavior and health outcomes using information from systematic reviews. 2) To assess the methodological quality of the systematic reviews found. METHODOLOGY/PRINCIPAL FINDINGS: Medline; Excerpta Medica (Embase); PsycINFO; and Web of Science were searched for reviews published up to September 2013. Additional publications were provided by Sedentary Behaviour Research Network members. The methodological quality of the systematic reviews was evaluated using recommended standard criteria from AMSTAR. For each review, improper use of causal language in the description of their main results/conclusion was evaluated. Altogether, 1,044 review titles were identified, 144 were read in their entirety, and 27 were included. Based on the systematic reviews with the best methodological quality, we found in children and adolescents, strong evidence of a relationship between time spent in sedentary behavior and obesity. Moreover, moderate evidence was observed for blood pressure and total cholesterol, self-esteem, social behavior problems, physical fitness and academic achievement. In adults, we found strong evidence of a relationship between sedentary behavior and all-cause mortality, fatal and non-fatal cardiovascular disease, type 2 diabetes and metabolic syndrome. In addition, there is moderate evidence for incidence rates of ovarian, colon and endometrial cancers. CONCLUSIONS: This overview based on the best available systematics reviews, shows that sedentary behavior may be an important determinant of health, independently of physical activity. However, the relationship is complex because it depends on the type of sedentary behavior and the age group studied. The relationship between sedentary behavior and many health outcomes remains uncertain; thus, further studies are warranted.

Sociodemographic and behavioral factors associated with physical activity in Brazilian adolescents.

BACKGROUND: Physical activity in adolescents is associated with short- and long-term health benefits. Physical activity can occur in various domains and is influenced by a complex network of factors. The aims of this study are 1) to describe the physical activity of Brazilian adolescents in physical education classes, during leisure time, and during active commuting and 2) to investigate the socio-demographic and behavioral factors associated with physical activity. METHODS: The representative sample included 109,104 Brazilian students in the final year of elementary school from 2,842 schools. The weekly frequency and duration of physical activity were assessed. A variety of socio-demographic and behavioral factors were studied. A multiple Poisson regression analysis was used to test for associations between physical activity and the socio-demographic and behavioral variables. RESULTS: Most of the students (97.0%) engaged in physical activity in at least one of the domains studied, especially physical education at school (81.7%) and leisure time physical activity (67.5%). However, only 29% of the adolescents reached the recommended level of physical activity. Among the adolescents who reached the minimum recommended time for physical activity, the various domains contributed the following proportions to total physical activity: leisure time physical activity (PR 12.5; 95% CI 11.17-13.97), active commuting (PR 1.63; 95% CI 1.59-1.67), and physical education at school (PR 1.36; 95% CI 1.29-1.44). The weekly frequency of all activities was greater among boys than among girls. Moreover, nearly two-thirds (61.8%) of students spent more than two hours per day engaging in sedentary behaviors; the prevalence of sedentary behaviors was similar between boys and girls (59.0 and 64.5%, respectively).Total level of physical activity, leisure time physical activity, and active commuting were associated with higher nutritional scores. CONCLUSIONS: Physical activity is important in any health promotion program. Therefore, it is necessary to invest in policies and interagency initiatives that promote all domains and to ensure that the general population helps determine the scope and design of such policies.

Sedentary behavior and health outcomes among older adults: a systematic review.

BACKGROUND: In the last decade, sedentary behavior has emerged as a new risk factor for health. The elderly spend most of their awake time in sedentary activities. Despite this high exposure, the impact of this sedentary behavior on the health of this population has not yet been reviewed. We systematically reviewed evidence for associations between sedentary behavior and multiple health outcomes in adults over 60 years of age. METHODS: We searched the Medline, Embase, Web of Science, SPORTDiscus, PsycINFO, CINAHL, LILLACS, and Sedentary Research Database for observational studies published up to May 2013. Additionally, we contacted members of the Sedentary Behaviour Research Network to identify articles that were potentially eligible. After inclusion, the methodological quality of the evidence was assessed in each study. RESULTS: We included 24 eligible articles in our systematic review, of which only 2 (8%) provided high-quality evidence. Greater sedentary time was related to an increased risk of all-cause mortality in the older adults. Some studies with a moderate quality of evidence indicated a relationship between sedentary behavior and metabolic syndrome, waist circumference, and overweightness/obesity. The findings for other outcomes such as mental health, renal cancer cells, and falls remain insufficient to draw conclusions. CONCLUSION: This systematic review supports the relationship between sedentary behavior and mortality in older adults. Additional studies with high methodological quality are still needed to develop informed guidelines for addressing sedentary behavior in older adults.