Alcohol drinking and risk of leukemia—A systematic review and meta-analysis of the dose–risk relation

The association between alcohol and leukemia risk has been addressed in several studies in the past two decades, but results have been inconsistent. Therefore, we conducted a systematic review and meta-analysis to quantify the dose–risk relation. Through the literature search up to August 2013, we identified 18 studies, 10 case-control and 8 cohorts, carried out in a total of 7142 leukemia cases. We derived pooled meta-analytic estimates using random-effects models, taking into account the correlation between estimates, and we performed a dose–risk analysis using a class of nonlinear random-effects meta-regression models. Stratified analyses were carried out on leukemia subtypes and groups, in order to identify possible etiologic differences. Compared with nondrinkers, the relative risks (RRs) for all leukemia were 0.94 [95% confidence interval (CI), 0.85–1.03], 0.90 (95% CI, 0.80–1.01) and 0.91 (95% CI, 0.81–1.02) for any, light (≤1 drink/day) and moderate to heavy (>1 drink/day) alcohol drinking, respectively. The summary RRs for any alcohol drinking were 1.47 (95% CI, 0.47–4.62) for acute lymphoblastic leukemia, 0.94 (95% CI 0.77–1.15) for chronic lymphocytic leukemia, 1.02 (95% CI, 0.86–1.21) for acute myeloid leukemia and 0.93 (95% CI 0.75–1.14) for chronic myeloid leukemia. The subgroup analysis on geographical area for all leukemia combined showed RRs of 0.84 (95% CI, 0.76–0.93), 0.92 (95% CI, 0.83–1.01) and 1.32 (95% CI, 1.02–1.70) for studies conducted in America, Europe and Asia, respectively. We did not find an increased risk of leukemia among alcohol drinkers. If any, a modest favorable effect emerged for light alcohol drinking, with a model-based risk reduction of approximately 10% in regular drinkers.     

Do estrogens always increase breast cancer risk?

The etiology of breast cancer is closely linked to the female hormone estrogen, with high life-time exposure being suggested to increase breast cancer risk [Nature 303 (1983) 767]. However, there appears to be a disparity between studies attempting to establish an association between high estrogen levels and breast cancer risk. This disparity becomes smaller by taking into consideration a timing factor, and we propose that estrogens can increase, decrease, or have no effect on breast cancer risk, depending on the timing of estrogen exposure. We further propose that the timing of estrogenic exposures may play at least as important a role in affecting breast cancer risk as life-time exposure.     

Does copulation increase the risk of predation?

Studies of mating behaviour have assumed that individuals are at greater risk when paired than when engaged in other activities. Recently, four experimental studies of insects and crustaceans have tested this assumption using predators from divergent taxa. Three of these studies indicate that mating carries no additional risk to the participants. Indeed, the findings suggest decreased vulnerability, relative to other activities, due to decreased predation on one or the other of the mating pair.     

Updating the “Risk Index”: A systematic review and meta-analysis of occupational injuries and work schedule characteristics

Fatigue is a major risk factor for occupational ‘accidents’ and injuries, and involves dimensions of physical, mental, and muscular fatigue. These dimensions are largely influenced by temporal aspects of work schedules. The “Risk Index” combines four fatigue-related components of work schedules to estimate occupational ‘accident’ and injury risk based on empirical trends: shift type (morning, afternoon/evening, night), length and consecutive number, and on-shift rest breaks. Since its first introduction in 2004, several additional studies have been published that allow the opportunity to improve the internal and external validity of the “Risk Index”. Thus, we updated the model’s estimates by systematically reviewing the literature and synthesizing study results using meta-analysis. Cochrane Collaboration directives and MOOSE guidelines were followed. We conducted systematic literature searches on each model component in Medline. An inverse variance approach to meta-analysis was used to synthesize study effect sizes and estimate between-studies variance (‘heterogeneity’). Meta-regression models were conducted to explain the heterogeneity using several effect modifiers, including the sample age and sex ratio. Among 3,183 initially identified abstracts, after screening by two independent raters (95–98% agreement), 29 high-quality studies were included in the meta-analysis. The following trends were observed: Shift type. Compared to morning shifts, injury risk significantly increased on night shifts (RR = 1.36 [95%CI = 1.15–1.60], n = 14 studies), while risk was slightly elevated on afternoon/evening shifts, although non-significantly (RR = 1.12 [0.76–1.64], n = 9 studies). Meta-regressions revealed worker’s age as a significant effect modifier: adolescent workers (≤ 20 y) showed a decreased risk on the afternoon/evening shift compared to both morning shifts and adult workers (p < 0.05). Number of consecutive shifts. Compared to the first shift in a block of consecutive shifts, risk increased exponentially for morning shifts (e.g., 4th: RR = 1.09 [0.90–1.32]; n = 6 studies) and night shifts (e.g., 4th: RR = 1.36 [1.14–1.62]; n = 8 studies), while risk on afternoon/evening shifts appeared unsystematic. Shift length. Injury risk rose substantially beyond the 9th hour on duty, a trend that was mirrored when looking at shift lengths (e.g., >12 h: RR = 1.34 [1.04–1.51], n = 3 studies). Rest breaks. Risk decreased for any rest break duration (e.g., 31–60 min: RR = 0.35 [0.29–0.43], n = 2 studies). With regards to time between breaks, risk increased with every additional half hour spent on the work task compared to the first 30 min (e.g., 90–119 min: RR = 1.62 [1.00–2.62], n = 3 studies). Rest break duration and interval seem to interact such that with increasing duration, the time between breaks becomes irrelevant. The updated “Risk Index”. All four components were combined to form the updated model and the relative risk values estimated for a variety of work schedules. The resulting “Risk Map” shows regions of highest risk when rest breaks are not taken frequently enough (i.e. <4 h) or are too short (i.e. <30 min), when shift length exceeds 11 h, and when work takes place during the night (particularly for >3 consecutive night shifts). The “Risk Index” is proposed as an empirical model to predict occupational ‘accident’ and injury risk based on the most recent data in the field, and can serve as a tool to evaluate hazards and maximize safety across different work schedules.     

A systematic review and meta-analysis of the association of transforming growth factor β receptor I 6A/9A gene polymorphism with ovarian cancer risk

Abstract

Ovarian cancer is the leading cause of cancer-related death in women. This meta-analysis was conducted to evaluate the association of transforming growth factor β receptor I (TβR-I) 6A/9A gene polymorphism with ovarian cancer risk. The association literatures were identified from PubMed and Cochrane Library on 1 October 2013, and eligible reports were recruited and synthesized. Four reports were recruited into this meta-analysis for the association of TβR-I 6A/9A gene polymorphism with ovarian cancer risk. 6A allele and 6A/6A genotype of TβR-I were associated with the ovarian cancer risk (6A: OR?=?1.24, 95% CI: 1.02–1.51, p?=?0.03; 6A/6A: OR?=?2.30, 95% CI: 1.01–5.22, p?=?0.05). However, TβR-I 9A/9A genotype was not associated with the risk of ovarian cancer (OR?=?0.82, 95% CI: 0.66–1.02, p?=?0.08). In conclusion, TβR-I 6A allele and 6A/6A genotype are associated with the ovarian cancer risk. However, more studies should be performed to confirm this relationship in the future.     

Aspirin “resistance” and risk of cardiovascular morbidity: systematic review and meta-analysis

Objective To determine if there is a relation between aspirin “resistance” and clinical outcomes in patients with cardiovascular disease.Design Systematic review and meta-analysis.Data source Electronic literature search without language restrictions of four databases and hand search of bibliographies for other relevant articles.Review methods Inclusion criteria included a test for platelet responsiveness and clinical outcomes. Aspirin resistance was assessed, using a variety of platelet function assays.Results 20 studies totalling 2930 patients with cardiovascular disease were identified. Most studies used aspirin regimens, ranging from 75-325 mg daily, and six studies included adjunct antiplatelet therapy. Compliance was confirmed directly in 14 studies and by telephone or interviews in three. Information was insufficient to assess compliance in three studies. Overall, 810 patients (28%) were classified as aspirin resistant. A cardiovascular related event occurred in 41% of patients (odds ratio 3.85, 95% confidence interval 3.08 to 4.80), death in 5.7% (5.99, 2.28 to 15.72), and an acute coronary syndrome in 39.4% (4.06, 2.96 to 5.56). Aspirin resistant patients did not benefit from other antiplatelet treatment.Conclusion Patients who are resistant to aspirin are at a greater risk of clinically important cardiovascular morbidity long term than patients who are sensitive to aspirin.     

Shift work and diabetes – A systematic review

Diabetes mellitus is a chronic disease, which has an increasing trend all over the world. Type 2 diabetes constitutes 90% of all diabetes. It is associated with weight gain and insulin resistance. Research during recent years has suggested that shift work could be a risk factor of type 2 diabetes. Since shift work is becoming more common, it could contribute to the increasing trend of diabetes. In this systematic review, we have studied the potential association between shift work and type 2 diabetes. We have also reviewed studies on control of diabetes in relation to shift work.     

Association between TNF-α-308 G/A gene polymorphism and gastric cancer risk: A systematic review and meta-analysis

ObjectiveTumor necrosis factor-alpha (TNF-α) has been found to be associated with gastric carcinogenesis, but individually published results have been inconclusive. The aim of this study was to explore the relationship between the TNF-α-308 G/A polymorphism and gastric cancer risk.MethodsMEDLINE, EMBASE and the COCHRANE library databases were searched for relevant articles to identify all available data. The odds ratios (ORs) with 95% confidence intervals (95% CIs) from each study were used to assess the association between the TNF-α-308 G/A polymorphism and gastric cancer risk.ResultsThis meta-analysis included 30 studies (32 datasets) involving 7009 gastric cancer cases and 12,119 control subjects. Overall, a significant association was found between the TNF-α-308 G/A polymorphism and gastric cancer in AA + GA vs. GG (dominant contrast model) (OR = 1.20, 95% CI = 1.07–1.34, p = 0.001). With stratification based on ethnicity, the TNF-α-308 G/A polymorphism was correlated with gastric cancer risk in Caucasians, using the dominant contrast model (OR = 0.74, 95% CI = 0.57–0.96, p = 0.02), but not in East Asians and other ethnic groups. In the comprehensive subgroup analysis, a significant association was also found in recent articles (published after 2005), population-based high-quality studies, hospital-based high-quality studies, studies using the TaqMan method and non-cardia subgroups. However, the TNF-α-308 G/A polymorphism was not associated with specific histological types of gastric cancer risk.ConclusionsThe TNF-α-308 G/A polymorphism may contribute to susceptibility to gastric cancer in Caucasians, especially for non-cardia gastric cancer, as most strongly demonstrated in high-quality studies and in studies using the TaqMan genotyping method. Furthermore, we recommend the TaqMan method as the preferred genotyping method in DNA polymorphism studies.     

Association between the XRCC3 polymorphisms and breast cancer risk: meta-analysis based on case–control studies

The previous published data on the association between X-ray repair cross-complementing group 3 (XRCC3) T241M, A4541G, and A17893G polymorphisms and breast cancer risk remained controversial. Hence, we performed a meta-analysis to investigate the association between breast cancer and XRCC3 T241M (21,910 cases and 23,961 controls), A4541G (9,633 cases and 10,994 controls), and A17893G polymorphisms (10,761 cases and 12,235 controls) in different inheritance models. When all the eligible studies were pooled into the meta-analysis of XRCC3 T241M polymorphism, significantly increased risk of breast cancer was observed in recessive model (odds' ratio [OR] = 1.10, 95% confidence interval [CI] = 1.04–1.16) and in additive model (OR = 1.10, 95% CI = 1.03–1.16). No significant association was found between A4541G polymorphism and breast cancer risk. When all the eligible studies were pooled into the meta-analysis of XRCC3 A17893G polymorphism, no significant association was found in any genetic model. Additionally, when one study was deleted in the sensitive analysis, the results of XRCC3 A17893G were changed in the additive model (OR = 0.90, 95% CI = 0.82–0.99) and dominant model (OR = 0.94, 95% CI = 0.89–0.99). In summary, this meta-analysis indicates that T241M polymorphism show an increased breast cancer risk and A17893G polymorphism may be associated with decreased breast cancer risk. A study with the larger sample size is needed to further evaluated gene-environment interaction on XRCC3 T241M, A4541G, and A17893G polymorphisms and breast cancer risk.     

Does lack of tocopherols and tocotrienols put women at increased risk of breast cancer?

Breast cancer is the leading site of new cancers in women and the second leading cause (after lung cancer) of cancer mortality in women. Observational studies that have collected data for dietary exposure to alpha-tocopherol with or without the other related tocopherols and tocotrienols have suggested that vitamin E from dietary sources may provide women with modest protection from breast cancer. However, there is no evidence that vitamin E supplements confer any protection whatever against breast cancer. Observational studies that have assessed exposure to vitamin E by plasma or adipose tissue concentrations of alpha-tocopherol have failed to provide consistent support for the idea that alpha-tocopherol provides any protection against breast cancer. In addition, evidence from studies in experimental animals suggest that alpha-tocopherol supplementation alone has little effect on mammary tumors. In contrast, studies in breast cancer cells indicate that alpha- gamma-, and delta-tocotrienol, and to a lesser extent delta-tocopherol, have potent antiproliferative and proapoptotic effects that would be expected to reduce risk of breast cancer. Many vegetable sources of alpha-tocopherol also contain other tocopherols or tocotrienols. Thus, it seems plausible that the modest protection from breast cancer associated with dietary vitamin E may be due to the effects of the other tocopherols and the tocotrienols in the diet. Additional studies will be required to determine whether this may be the case, and to identify the most active tocopherol/tocotrienol.     

Adiponectin,TNF-α and inflammatory cytokines and risk of type 2 diabetes: A systematic review and meta-analysis

AimsThere has been growing evidence that adiponectin, tumor necrosis factor-α (TNF-α) and inflammatory cytokines involved in insulin resistance and may be attractive candidates for assessing risk of the incident type 2 diabetes (T2DM). A systematic review and meta-analysis of prospective studies was conducted to assess the associations of levels of serum adiponectin, TNF-α and inflammatory markers (Interleukin-1 beta (IL-1β), Interleukin-6 (IL-6), Interleukin-18 (IL-18), C-reactive protein (CRP)) with risk of T2DM.Materials/methodsWe searched PubMed, ISI Web of Knowledge, EMBASE, and Cochrane Library databases up until February 1, 2016 for eligible studies which were matched to search subjects. Either fixed-effects or random-effects models were used to estimate the summary risk incorporated between study variations.Results19 studies comprising a total of 39,136 participants and 7924 cases were included in the meta-analysis. Our findings showed that an obvious association of elevated CRP levels with T2DM risk (relative risk [RR] 1.48 [95% CI 1.26–1.71]), with the absence of publication bias. For IL-6, the meta-analysis involved 16 cohorts with a total of 24,929 participants and 4751 cases. Using data from all trials, a strong positive correlation (1.32 [1.14, 1.51]) was observed between basal plasma IL-6 and T2DM, whereas relatively lower relation between TNF-α (1.16 [0.87, 1.45]), IL-18 (1.45 [1.16, 1.73]), IL-1β (0.87, [0.59, 1.15]) and independently increased risk to occurrence of T2DM. Conversely, we also found that the level of adiponectin decreased significantly in patients with T2DM. Sensitivity analyses further supported the associations.ConclusionsThis meta-analysis indicates that T2DM risk as whole was strongly associated with elevated levels of inflammatory cytokines (IL-1β, IL-6, IL-18, CRP), TNF-α and low levels of adiponectin. Despite an overall detectable association in the meta-analysis, considerable heterogeneity existed between studies. Further work is needed, it seems clear that a complex interplay of inflammation and the development of DM. Moreover, these biomarkers are predictors of T2DM subjects and should take more attention to measure levels of these as well as to target therapy/interventions.     

Does the modern urbanized sleeping habitat pose a breast cancer risk?

Due to its disruptive effects on circadian rhythms and sleep deprivation at night, shiftworking is currently recognized as a risk factor for breast cancer (BC). As revealed by the present analysis based on a comparative case-control study of 1679 women, exposure to light-at-night (LAN) in the "sleeping habitat" is significantly associated with BC risk (odds ratio [OR]?=?1.220, 95% confidence interval [CI]?=?1.118-1.311; p?相似文献   

What are the sleep characteristics of elite female athletes? A systematic review with meta-analysis

With the recent growth in female sport, practitioners need to be able to provide specific support to female athletes to ensure their sleep, health and athletic performance are optimised. Examine the patterns, duration and quality of sleep among elite female athletes, and consider the impact of situational challenges and their effects on the sleep of elite female athletes. Data was located through a search of SPORTDiscus, MEDLINE and Scopus from inception up to May 2021. Studies needed to be peer-reviewed research reporting quantitative sleep outcomes for female athletes ≥ 18 years of age and competing at a predefined elite level. A meta-analysis was performed on habitual sleep outcomes (e.g. total sleep time [TST] and sleep efficiency [SE]) measured with actigraphy. A total of 38 studies were included. Meta-analysis showed habitual TST (n = 14) was 7.8 h [7.4, 8.2] (mean [95% CI]), and SE was 86.7% [84.7, 88.6], with high variability among studies (I² = 97.8–98.2%). Subjective sleep complaints are common before a competition, as do post-training sleep disturbances (63% studies report TST decrease), and post-competition sleep disturbances (75% studies report TST decrease). Female athletes achieve satisfactory objective sleep quantity and quality during habitual periods, but experience sleep disturbances pre- and post-situational challenges. There is high variability of objective sleep outcomes, demonstrating the individual nature of habitual female athlete sleep. Overall, future research must focus on optimising the sleep appraisal methods and creating high-quality study designs in a broader number of sports.     

Are older patients less likely to be treated for pancreatic cancer? A systematic review and meta-analysis

Pancreatic cancer is the seventh commonest cause of cancer-related death worldwide. Although prognosis is poor, both surgery and adjuvant chemotherapy improve survival. However, it has been suggested that not all pancreatic cancer patients who may benefit from treatment receive it. This systematic review and meta-analysis investigated the existence of age-related inequalities in receipt of first-line pancreatic cancer treatment. Medline, Embase, Cochrane Library and grey literature were searched for population-based studies investigating treatment receipt, reported by age, for patients with primary pancreatic cancer from inception until 4th June 2020, and updated 5th August 2021. Studies from countries with universal healthcare were included, to minimise influence of health system-related economic factors. A modified version of the Newcastle-Ottawa Scale was used to assess risk of bias. Random-effects meta-analysis was undertaken comparing likelihood of treatment receipt in older versus younger patients. Sensitivity and subgroup analyses were conducted. Eighteen papers were included; 12 independent populations were eligible for meta-analysis. In most studies, < 10% of older patients were treated. Older age (generally ≥65) was significantly associated with reduced receipt of any treatment (OR=0.14, 95% CI 0.10–0.21, n = 12 studies), surgery (OR=0.15, 95% CI 0.09–0.24, n = 9 studies) and chemotherapy as a primary treatment (OR=0.13, 95% CI 0.07–0.24, n = 5 studies). The effect of age was independent of methodological quality, patient population or time-period of patient diagnosis and remained in studies with confounder adjustment. The mean quality score of included studies was 6/8. Inequalities in receipt of healthcare interventions across social groups is a recognised concern internationally. This review shows that older age is significantly, and consistently, associated with non-receipt of treatment in pancreatic cancer. However, there are risks and side-effects associated with pancreatic cancer treatment. Further research on what influences patient and professional treatment decision-making is required to better understand these apparent inequalities.     

Global estimate of gastric cancer in Helicobacter pylori–infected population: A systematic review and meta-analysis

There is information regarding the rates of gastric cancer (GC) in different populations and the important role of Helicobacter pylori in GC development; however, no comprehensive study has yet been performed to investigate the prevalence of GC in H. pylori–infected patients. PubMed, Embase, and Cochrane Library through January 1, 2000 were searched without language restrictions. Quality of included studies was assessed with a critical appraisal checklist recommended by the Joanna Briggs Institute. All of the analyses were conducted using Comprehensive Meta-Analysis Software Version 2.0 and Stata 14.0. Forty-four studies from 17 countries were included. The pooled frequency of GC was 17.4% (95% confidence interval: 16.4–18.5) in H. pylori–infected population. The frequency of GC among H. pylori–infected population varied markedly across countries. The highest rate of GC was observed in H. pylori–infected individuals from Asian countries. The frequency of GC was relatively high in H. pylori–infected population in the world. However, the eradication of H. pylori might be a promising strategy for GC prevention, especially in high-risk populations such as Asian countries.     

What implementation interventions increase cancer screening rates? a systematic review

Background

Appropriate screening may reduce the mortality and morbidity of colorectal, breast, and cervical cancers. However, effective implementation strategies are warranted if the full benefits of screening are to be realized. As part of a larger agenda to create an implementation guideline, we conducted a systematic review to evaluate interventions designed to increase the rate of breast, cervical, and colorectal cancer (CRC) screening. The interventions considered were: client reminders, client incentives, mass media, small media, group education, one-on-one education, reduction in structural barriers, reduction in out-of-pocket costs, provider assessment and feedback interventions, and provider incentives. Our primary outcome, screening completion, was calculated as the overall median post-intervention absolute percentage point (PP) change in completed screening tests.

Methods

Our first step was to conduct an iterative scoping review in the research area. This yielded three relevant high-quality systematic reviews. Serving as our evidentiary foundation, we conducted a formal update. Randomized controlled trials and cluster randomized controlled trials, published between 2004 and 2010, were searched in MEDLINE, EMBASE and PSYCHinfo.

Results

The update yielded 66 studies new eligible studies with 74 comparisons. The new studies ranged considerably in quality. Client reminders, small media, and provider audit and feedback appear to be effective interventions to increase the uptake of screening for three cancers. One-on-one education and reduction of structural barriers also appears effective, but their roles with CRC and cervical screening, respectively, are less established. More study is required to assess client incentives, mass media, group education, reduction of out-of-pocket costs, and provider incentive interventions.

Conclusion

The new evidence generally aligns with the evidence and conclusions from the original systematic reviews. This review served as the evidentiary foundation for an implementation guideline. Poor reporting, lack of precision and consistency in defining operational elements, and insufficient consideration of context and differences among populations are areas for additional research.