METHODS AND ANALYSIS: We will conduct a scoping review according to the framework proposed by Arksey and O'Malley (2005). We will search MEDLINE, EMBASE, Web of Science and Google Scholar using a combination of terms such as "colorectal cancer", "screening" and "low-middle-income countries". Studies of CRC screening interventions/programmes conducted in the general adult population in LMICs as well as policy reviews (of interventions in LMICs) and commentaries on challenges and opportunities of delivering CRC screening in LMICs, published in the English language before February 2020 will be included in this review. The title and abstract screen will be conducted by one reviewer and two reviewers will screen full-texts and extract data from included papers, independently, into a data charting template that will include criteria from an adapted template for intervention description and replication checklist and implementation considerations. The presentation of the scoping review will be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews guidance.
ETHICS AND DISSEMINATION: There are no ethical concerns. The results will be used to inform colorectal screening interventions in LMICs. We will publish the findings in a peer-reviewed journal and present them at relevant conferences.
METHODS: We systematically followed a five-step scoping review framework to identify and review relevant literature about CRC screening in LMICs, written in the English language before February 2020. We searched Medline, Embase, Web of Science and Google Scholar for studies targeting the general, asymptomatic, at-risk adult population. The TIDieR tool and an implementation checklist were used to extract data from empirical studies; and we extracted data-informed insights from policy reviews and commentaries.
RESULTS: CRC screening interventions (n = 24 studies) were implemented in nine middle-income countries. Population-based screening programmes (n = 11) as well as small-scale screening interventions (n = 13) utilised various recruitment strategies. Interventions that recruited participants face-to-face (alone or in combination with other recruitment strategies) (10/15), opportunistic clinic-based screening interventions (5/6) and educational interventions combined with screening (3/4), seemed to be the strategies that consistently achieved an uptake of > 65% in LMICs. FOBT/FIT and colonoscopy uptake ranged between 14 and 100%. The most commonly reported implementation indicator was 'uptake/reach'. There was an absence of detail regarding implementation indicators and there is a need to improve reporting practice in order to disseminate learning about how to implement programmes.
CONCLUSION: Opportunities and challenges for the implementation of CRC screening programmes were related to the reporting of CRC cases and screening, cost-effective screening methods, knowledge about CRC and screening, staff resources and training, infrastructure of the health care system, financial resources, public health campaigns, policy commitment from governments, patient navigation, planning of screening programmes and quality assurance.
METHODS: This quasi-experimental study was informed by the Implementation Research Logic Model and evaluated with the RE-AIM framework. Trained data collectors recruited by phone, randomly selected, asymptomatic adults aged 50-75 years from Segamat District, who previously completed a health census form for the South East Asia Community Observatory (SEACO). Participants were posted an iFOBT kit and asked to return a photo of the completed test for screening by health care professionals. A regression analysis of evaluation data was conducted to identify which variables were associated with the outcome indicators of 'study participation' and 'iFOBT completion' and the CRC-SIM was evaluated in terms of its appropriateness, feasibility and acceptability.
RESULTS: Seven hundred forty-seven eligible adults (52%) agreed to participate in this study and received an iFOBT kit. Participation was significantly lower amongst Chinese Malaysians (adjusted OR 0.45, 95% CI 0.35 - 0.59, p<0.001) compared to Malays and amongst participants from the rural sub-district (Gemereh) (adjusted OR 0.71, 95% CI 0.54 - 0.92, p=0.011) compared to the urban sub-district (Sungai Segamat). Less than half of participants (42%, n=311/747) completed the iFOBT. Test-kit completion was significantly higher amongst Chinese Malaysians (adjusted OR 3.15, 95% CI 2.11 - 4.69, p<0.001) and lower amongst participants with a monthly household income ≥RM 4,850 (adjusted OR 0.58, 95% CI 0.39 - 0.87, p=0.009) compared to participants with a lower household income. The main reported reason for non-participation was 'not interested' (58.6%) and main implementation challenges related to invalid photographs from participants and engaging iFOBT positive participants in further clinic consultations and procedures.
CONCLUSION: Home-testing for CRC (test completion) appeared to be acceptable to only around one-fifth of the target population in Malaysia. However, mindful of the challenging circumstances surrounding the pandemic, the CRC-SIM merits consideration by public health planners as a method of increasing screening in Malaysia, and other low- and middle-income countries.
METHODS AND ANALYSIS: The implementation research logic model guided the development of the study and implementation outcome measures were informed by the 'Reach, Effectiveness, Adoption, Implementation and Maintenance' (RE-AIM) framework. This CRC screening intervention for Malaysia uses home-testing and digital, small media, communication to improve CRC screening uptake. A sample of 780 people aged 50-75 years living in Segamat district, Malaysia, will be selected randomly from the South East Asia Community Observatory (SEACO) database. Participants will receive a screening pack as well as a WhatsApp video of a local doctor to undertake a stool test safely and to send a photo of the test result to a confidential mobile number. SEACO staff will inform participants of their result. Quantitative data about follow-up clinic attendance, subsequent hospital tests and outcomes will be collected. Logistic regression will be used to investigate variables that influence screening completion and we will conduct a budget impact-analysis of the intervention and its implementation. Qualitative data about intervention implementation from the perspective of participants and stakeholders will be analysed thematically.
ETHICS AND DISSEMINATION: Ethics approval has been granted by Monash University Human Research Ethics Committee (MUHREC ID: 29107) and the Medical Review and Ethics Committee (Reference: 21-02045-O7G(2)). Results will be disseminated through publications, conferences and community engagement activities.
TRIAL REGISTRATION NUMBER: National Medical Research Register Malaysia: 21-02045-O7G(2).
METHODS: This is a meta-analysis of seven prospective cohort studies participating in the CHANCES consortium including 18 668 men and 24 751 women with a mean age of 62 and 63 years, respectively. Harmonised individual participant data from all seven cohorts were analysed separately and alternatively for each anthropometric indicator using multivariable Cox proportional hazards models.
RESULTS: After a median follow-up period of 12 years, 1656 first-incident obesity-related cancers (defined as postmenopausal female breast, colorectum, lower oesophagus, cardia stomach, liver, gallbladder, pancreas, endometrium, ovary, and kidney) had occurred in men and women. In the meta-analysis of all studies, associations between indicators of adiposity, per s.d. increment, and risk for all obesity-related cancers combined yielded the following summary hazard ratios: 1.11 (95% CI 1.02-1.21) for BMI, 1.13 (95% CI 1.04-1.23) for WC, 1.09 (95% CI 0.98-1.21) for HC, and 1.15 (95% CI 1.00-1.32) for WHR. Increases in risk for colorectal cancer were 16%, 21%, 15%, and 20%, respectively per s.d. of BMI, WC, HC, and WHR. Effect modification by hormone therapy (HT) use was observed for postmenopausal breast cancer (Pinteraction<0.001), where never HT users showed an ∼20% increased risk per s.d. of BMI, WC, and HC compared to ever users.
CONCLUSIONS: BMI, WC, HC, and WHR show comparable positive associations with obesity-related cancers combined and with colorectal cancer in older adults. For postmenopausal breast cancer we report evidence for effect modification by HT use.
DESIGN: Individual participant meta-analysis using data from 25 cohorts participating in the CHANCES consortium. Data were harmonised, analysed separately employing Cox proportional hazard regression models, and combined by meta-analysis.
RESULTS: Overall, 503,905 participants aged 60 and older were included in this study, of whom 37,952 died from cardiovascular disease. Random effects meta-analysis of the association of smoking status with cardiovascular mortality yielded a summary hazard ratio of 2.07 (95% CI 1.82 to 2.36) for current smokers and 1.37 (1.25 to 1.49) for former smokers compared with never smokers. Corresponding summary estimates for risk advancement periods were 5.50 years (4.25 to 6.75) for current smokers and 2.16 years (1.38 to 2.39) for former smokers. The excess risk in smokers increased with cigarette consumption in a dose-response manner, and decreased continuously with time since smoking cessation in former smokers. Relative risk estimates for acute coronary events and for stroke events were somewhat lower than for cardiovascular mortality, but patterns were similar.
CONCLUSIONS: Our study corroborates and expands evidence from previous studies in showing that smoking is a strong independent risk factor of cardiovascular events and mortality even at older age, advancing cardiovascular mortality by more than five years, and demonstrating that smoking cessation in these age groups is still beneficial in reducing the excess risk.
OBJECTIVE: The objective was to generate evidence on the association between WHO dietary recommendations and mortality from CVD, coronary artery disease (CAD), and stroke in the elderly aged ≥60 y.
DESIGN: We analyzed data from 10 prospective cohort studies from Europe and the United States comprising a total sample of 281,874 men and women free from chronic diseases at baseline. Components of the Healthy Diet Indicator (HDI) included saturated fatty acids, polyunsaturated fatty acids, mono- and disaccharides, protein, cholesterol, dietary fiber, and fruit and vegetables. Cohort-specific HRs adjusted for sex, education, smoking, physical activity, and energy and alcohol intakes were pooled by using a random-effects model.
RESULTS: During 3,322,768 person-years of follow-up, 12,492 people died of CVD. An increase of 10 HDI points (complete adherence to an additional WHO guideline) was, on average, not associated with CVD mortality (HR: 0.94; 95% CI: 0.86, 1.03), CAD mortality (HR: 0.99; 95% CI: 0.85, 1.14), or stroke mortality (HR: 0.95; 95% CI: 0.88, 1.03). However, after stratification of the data by geographic region, adherence to the HDI was associated with reduced CVD mortality in the southern European cohorts (HR: 0.87; 95% CI: 0.79, 0.96; I(2) = 0%) and in the US cohort (HR: 0.85; 95% CI: 0.83, 0.87; I(2) = not applicable).
CONCLUSION: Overall, greater adherence to the WHO dietary guidelines was not significantly associated with CVD mortality, but the results varied across regions. Clear inverse associations were observed in elderly populations in southern Europe and the United States.
PATIENTS AND METHODS: For this individual patient data meta-analysis, sociodemographic and smoking behavior information of 12 414 incident CRC patients (median age at diagnosis: 64.3 years), recruited within 14 prospective cohort studies among previously cancer-free adults, was collected at baseline and harmonized across studies. Vital status and causes of death were collected for a mean follow-up time of 5.1 years following cancer diagnosis. Associations of smoking behavior with overall and CRC-specific survival were evaluated using Cox regression and standard meta-analysis methodology.
RESULTS: A total of 5229 participants died, 3194 from CRC. Cox regression revealed significant associations between former [hazard ratio (HR) = 1.12; 95 % confidence interval (CI) = 1.04-1.20] and current smoking (HR = 1.29; 95% CI = 1.04-1.60) and poorer overall survival compared with never smoking. Compared with current smoking, smoking cessation was associated with improved overall (HR<10 years = 0.78; 95% CI = 0.69-0.88; HR≥10 years = 0.78; 95% CI = 0.63-0.97) and CRC-specific survival (HR≥10 years = 0.76; 95% CI = 0.67-0.85).
CONCLUSION: In this large meta-analysis including primary data of incident CRC patients from 14 prospective cohort studies on the association between smoking and CRC prognosis, former and current smoking were associated with poorer CRC prognosis compared with never smoking. Smoking cessation was associated with improved survival when compared with current smokers. Future studies should further quantify the benefits of nonsmoking, both for cancer prevention and for improving survival among CRC patients, in particular also in terms of treatment response.
METHODS: Relative mortality and mortality rate advancement periods (RAPs) were estimated by Cox proportional hazards models for the population-based prospective cohort studies from Europe and the U.S. (CHANCES [Consortium on Health and Ageing: Network of Cohorts in Europe and the U.S.]), and subsequently pooled by individual participant meta-analysis. Statistical analyses were performed from June 2013 to March 2014.
RESULTS: A total of 489,056 participants aged ≥60 years at baseline from 22 population-based cohort studies were included. Overall, 99,298 deaths were recorded. Current smokers had 2-fold and former smokers had 1.3-fold increased mortality compared with never smokers. These increases in mortality translated to RAPs of 6.4 (95% CI=4.8, 7.9) and 2.4 (95% CI=1.5, 3.4) years, respectively. A clear positive dose-response relationship was observed between number of currently smoked cigarettes and mortality. For former smokers, excess mortality and RAPs decreased with time since cessation, with RAPs of 3.9 (95% CI=3.0, 4.7), 2.7 (95% CI=1.8, 3.6), and 0.7 (95% CI=0.2, 1.1) for those who had quit <10, 10 to 19, and ≥20 years ago, respectively.
CONCLUSIONS: Smoking remains as a strong risk factor for premature mortality in older individuals and cessation remains beneficial even at advanced ages. Efforts to support smoking abstinence at all ages should be a public health priority.