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White rice, brown rice and the risk of type 2 diabetes: a systematic review and meta-analysis.
Yu, J, Balaji, B, Tinajero, M, Jarvis, S, Khan, T, Vasudevan, S, Ranawana, V, Poobalan, A, Bhupathiraju, S, Sun, Q, et al
BMJ open. 2022;12(9):e065426
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The prevalence of type 2 diabetes (T2D) has continued to increase worldwide, especially in low-income and middle-income countries. Since rice is a staple food in many cultures and is predominant in most Asian diets, it is hypothesised that improving diet quality by replacing white rice with brown rice could play an important role in the prevention of T2D. The aim of this study was to assess the relationship between rice intake and the risk of T2D. This study is a systematic review and meta-analysis of nineteen studies – 8 cohort studies and 11 randomised controlled trials. Results from the meta-analyses of the cohort studies show a positive association between intake of white rice and risk of T2D. The associations were stronger in women compared with men. Additionally, brown rice was inversely associated with risk of T2D however, the results are based on limited data. Furthermore, the randomised controlled trials showed that the between-group difference in high-density lipoprotein cholesterol was statistically significant in favour of the brown rice group. Authors conclude that replacing white rice with brown rice or other whole grains has the potential to be a low-cost and feasible lifestyle strategy to improve diet quality and help reduce T2D risk.
Abstract
OBJECTIVE Intake of white rice has been associated with elevated risk for type 2 diabetes (T2D), while studies on brown rice are conflicting. To inform dietary guidance, we synthesised the evidence on white rice and brown rice with T2D risk. DESIGN Systematic review and meta-analysis. DATA SOURCES PubMed, EMBASE and Cochrane databases were searched through November 2021. ELIGIBILITY CRITERIA Prospective cohort studies of white and brown rice intake on T2D risk (≥1 year), and randomised controlled trials (RCTs) comparing brown rice with white rice on cardiometabolic risk factors (≥2 weeks). DATA EXTRACTION AND SYNTHESIS Data were extracted by the primary reviewer and two additional reviewers. Meta-analyses were conducted using random-effects models and reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Risk of bias was assessed using the Newcastle Ottawa Scale for prospective cohort studies and the Cochrane Risk of Bias Tool for RCTs. Strength of the meta-evidence was assessed using NutriGrade. RESULTS Nineteen articles were included: 8 cohort studies providing 18 estimates (white rice: 15 estimates, 25 956 cases, n=5 77 426; brown rice: 3 estimates, 10 507 cases, n=1 97 228) and 11 RCTs (n=1034). In cohort studies, white rice was associated with higher risk of T2D (pooled RR, 1.16; 95% CI: 1.02 to 1.32) comparing extreme categories. At intakes above ~300 g/day, a dose-response was observed (each 158 g/day serving was associated with 13% (11%-15%) higher risk of T2D). Intake of brown rice was associated with lower risk of T2D (pooled RR, 0.89; 95% CI: 0.81 to 0.97) comparing extreme categories. Each 50 g/day serving of brown rice was associated with 13% (6%-20%) lower risk of T2D. Cohort studies were considered to be of good or fair quality. RCTs showed an increase in high-density lipoprotein-cholesterol (0.06 mmol/L; 0.00 to 0.11 mmol/L) in the brown compared with white rice group. No other significant differences in risk factors were observed. The majority of RCTs were found to have some concern for risk of bias. Overall strength of the meta-evidence was moderate for cohort studies and moderate and low for RCTs. CONCLUSION Intake of white rice was associated with higher risk of T2D, while intake of brown rice was associated with lower risk. Findings from substitution trials on cardiometabolic risk factors were inconsistent. PROSPERO REGISTRATION NUMBER CRD42020158466.
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Pasta meal intake in relation to risks of type 2 diabetes and atherosclerotic cardiovascular disease in postmenopausal women : findings from the Women's Health Initiative.
Huang, M, Lo, K, Li, J, Allison, M, Wu, WC, Liu, S
BMJ nutrition, prevention & health. 2021;4(1):195-205
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Among major sources of dietary carbohydrates, pasta has long been a staple food in diverse human cultures around the world. Interest in the health effects of pasta on the human body has steadily increased since the 1980s. The aim of this study was to evaluate the association between pasta meal intake and long-term risk of developing diabetes or atherosclerotic cardiovascular disease (ASCVD, including coronary heart disease (CHD) and stroke) in postmenopausal women. This study is a large prospective cohort study of 84, 555 post-menopausal women aged between 50 and 79 years. Results show a significant association between higher intakes of pasta meal and long-term risk of developing stroke and ASCVD, and a suggestive association between higher intakes of pasta meal and long-term risk of developing CHD, while no significant relation was observed between pasta meal intake and risk of developing diabetes. Authors conclude that substituting pasta meal for other commonly consumed starchy foods such as fried potato or white bread may possibly represent a feasible and easy-to-implement method of dietary modification to improve cardiometabolic outcomes.
Abstract
OBJECTIVE To evaluate the association between pasta meal intake and long-term risk of developing diabetes or atherosclerotic cardiovascular disease (ASCVD, including coronary heart disease (CHD) and stroke) in postmenopausal women. DESIGN Prospective cohort study. SETTING Women's Health Initiative (WHI) in the USA. PARTICIPANTS 84 555 postmenopausal women aged 50-79 in 1994, who were free of diabetes, ASCVD and cancer at baseline who were not in the dietary modification trial of the WHI, completed a validated food frequency questionnaire, and were evaluated for incident diabetes and ASCVD outcomes during the follow-up until 2010. MAIN OUTCOME MEASURE Diabetes and ASCVD. RESULTS Cox proportional hazards models were used to estimate the association (HR) between quartiles of pasta meal consumption (residuals after adjusting for total energy) and the risk of incidence diabetes, CHD, stroke or ASCVD, accounting for potential confounding factors, with testing for linear trend. We then statistically evaluated the effect of substituting white bread or fried potato for pasta meal on disease risk. When comparing the highest to the lowest quartiles of residual pasta meal intake, we observed significantly reduced risk of ASCVD (HR=0.89, 95% CI 0.83 to 0.96, p trend=0.002), stroke (HR=0.84, 95% CI 0.75 to 0.93, p trend=0.001), CHD (HR=0.91, 95% CI 0.83 to 1.00, p trend=0.058) and no significant alteration in diabetes risk (HR=1.02, 95% CI 0.96 to 1.07, p trend=0.328). Replacing white bread or fried potato with pasta meal was statistically associated with decreased risk of stroke and ASCVD. CONCLUSIONS Pasta meal intake did not have adverse effects on long-term diabetes risk and may be associated with significant reduced risk of stroke and ASCVD. The potential benefit of substituting pasta meal for other commonly consumed starchy foods on cardiometabolic outcomes warrants further investigation in additional high-quality and large prospective studies of diverse populations.
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Influence of GDM Diagnosis and Treatment on Weight Gain, Dietary Intake and Physical Activity in Pregnant Women with Obesity: Secondary Analysis of the UPBEAT Study.
Atakora, L, Poston, L, Hayes, L, Flynn, AC, White, SL
Nutrients. 2020;12(2)
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Obesity during pregnancy increases the risk of development of gestational diabetes (GDM), which can develop into type 2 diabetes postnatally. The UK has guidelines on diet and exercise in place following a positive result for GDM, however it is unclear how results from a GDM test may affect behaviours and weight gain in women with obesity during pregnancy. This secondary analysis of a randomised control trial; the UK pregnancies better eating and activity trial (UPBEAT), aimed to assess how a negative or positive diagnosis of GDM affects the diet, physical activity levels and weight gain of pregnant women with obesity. 1031 pregnant women who were positively and negatively diagnosed with GDM were randomly split into two groups for eight weeks. The intervention group received additional appointments with a health coach as well as regular antenatal appointments. The results showed that women who received a negative result to GDM gained significantly more weight than those with a positive diagnosis regardless of which treatment group they were allocated. GDM status also affected dietary intake, however no changes in amount of physical activity were seen with either diagnosis. It was concluded that pregnant women with obesity gained more weight if they received a negative result to GDM and a positive GDM result is associated with lower weight gain and dietary changes. This highlights the need for additional diet and weight gain strategies for pregnant women with obesity who return a negative GDM result. Clinicians could use this study to stress the importance of healthy eating and exercise to pregnant women with obesity, even if a negative GDM test is received.
Abstract
Obesity during pregnancy is associated with the development of gestational diabetes (GDM). This study aimed to assess if the result of an oral glucose tolerance test (OGTT) for GDM influences health (diet and physical activity) behaviours of pregnant women with obesity. In total, 1031 women who participated in the UK Pregnancies Better Eating and Activity Trial (UPBEAT) of a lifestyle intervention from early pregnancy were included. Changes in weight gain, dietary intake and physical activity following an OGTT undertaken between 27+0 and 28+6 weeks' and 34 and 36 weeks' gestation were examined using linear regression with appropriate adjustment for confounders. Obese women without GDM (IADPSG criteria) gained 1.9 kg (95% CI -2.2, -1.5, p < 0.001) more weight than women with GDM. Women with GDM demonstrated greater reductions in energy (-142kcal, 95%CI -242.2, -41.9, p = 0.006), carbohydrate intake (-1.5%E 95%CI -2.8, -0.3, p = 0.016) and glycaemic load (-15.2, 95%CI -23.6, -6.7, p < 0.001) and a greater increase in protein intake (2%E, 95%CI 1.3, 2.7, p < 0.001), compared to women without GDM. Trial intervention allocation did not influence any associations observed. The findings emphasise the need for strategies to optimise the health behaviours of pregnant women with obesity, following a negative OGTT for GDM.
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Sociodemographic and lifestyle-related risk factors for identifying vulnerable groups for type 2 diabetes: a narrative review with emphasis on data from Europe.
Kyrou, I, Tsigos, C, Mavrogianni, C, Cardon, G, Van Stappen, V, Latomme, J, Kivelä, J, Wikström, K, Tsochev, K, Nanasi, A, et al
BMC endocrine disorders. 2020;20(Suppl 1):134
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Type 2 diabetes mellitus (T2DM) results from progressive loss of insulin secretion, which is typically combined with various degrees of insulin resistance. The aim of this study is to provide a comprehensive overview of key sociodemographic and lifestyle-related risk factors for identifying vulnerable groups for T2DM with emphasis on data from Europe. This study is a narrative review which includes 101 publications. Literature shows that prevention of T2DM should be a collaborative effort which mobilizes multiple partners/ stakeholders at a national and international (e.g. European) level. In addition, a holistic approach is becoming increasingly essential in order to put into effect multidimensional public health programs and integrated interventions for effective T2DM prevention which will take into account both traditional and socioeconomic/socioecological factors. Authors conclude that a multidimensional approach for the prevention of T2DM may have a broader impact against the current diabesity epidemic within and across countries in Europe.
Abstract
BACKGROUND Type 2 diabetes mellitus (T2DM) comprises the vast majority of all diabetes cases in adults, with alarmingly increasing prevalence over the past few decades worldwide. A particularly heavy healthcare burden of diabetes is noted in Europe, where 8.8% of the population aged 20-79 years is estimated to have diabetes according to the International Diabetes Federation. Multiple risk factors are implicated in the pathogenesis of T2DM with complex underlying interplay and intricate gene-environment interactions. Thus, intense research has been focused on studying the role of T2DM risk factors and on identifying vulnerable groups for T2DM in the general population which can then be targeted for prevention interventions. METHODS For this narrative review, we conducted a comprehensive search of the existing literature on T2DM risk factors, focusing on studies in adult cohorts from European countries which were published in English after January 2000. RESULTS Multiple lifestyle-related and sociodemographic factors were identified as related to high T2DM risk, including age, ethnicity, family history, low socioeconomic status, obesity, metabolic syndrome and each of its components, as well as certain unhealthy lifestyle behaviors. As Europe has an increasingly aging population, multiple migrant and ethnic minority groups and significant socioeconomic diversity both within and across different countries, this review focuses not only on modifiable T2DM risk factors, but also on the impact of pertinent demographic and socioeconomic factors. CONCLUSION In addition to other T2DM risk factors, low socioeconomic status can significantly increase the risk for prediabetes and T2DM, but is often overlooked. In multinational and multicultural regions such as Europe, a holistic approach, which will take into account both traditional and socioeconomic/socioecological factors, is becoming increasingly crucial in order to implement multidimensional public health programs and integrated community-based interventions for effective T2DM prevention.
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Dietary Glycemic Index and Load and the Risk of Type 2 Diabetes: Assessment of Causal Relations.
Livesey, G, Taylor, R, Livesey, HF, Buyken, AE, Jenkins, DJA, Augustin, LSA, Sievenpiper, JL, Barclay, AW, Liu, S, Wolever, TMS, et al
Nutrients. 2019;11(6)
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It is generally accepted that certain diet and lifestyle choices contribute to a person’s risk of developing type 2 diabetes (T2D). In this meta-analysis, researchers set out to review previous studies and assess whether there is any evidence that the amount and type of carbohydrate (measured by Glycaemic Index (GI) and Glycaemic Load (GL)) in a person’s diet has a direct influence on their risk of developing T2D. The authors concluded with a high level of confidence that eating high GI and GL foods can lead to a higher risk of developing T2D. They suggest that nutrition advice that favours low GI and GL foods could produce significant cost savings for public healthcare.
Abstract
While dietary factors are important modifiable risk factors for type 2 diabetes (T2D), the causal role of carbohydrate quality in nutrition remains controversial. Dietary glycemic index (GI) and glycemic load (GL) have been examined in relation to the risk of T2D in multiple prospective cohort studies. Previous meta-analyses indicate significant relations but consideration of causality has been minimal. Here, the results of our recent meta-analyses of prospective cohort studies of 4 to 26-y follow-up are interpreted in the context of the nine Bradford-Hill criteria for causality, that is: (1) Strength of Association, (2) Consistency, (3) Specificity, (4) Temporality, (5) Biological Gradient, (6) Plausibility, (7) Experimental evidence, (8) Analogy, and (9) Coherence. These criteria necessitated referral to a body of literature wider than prospective cohort studies alone, especially in criteria 6 to 9. In this analysis, all nine of the Hill's criteria were met for GI and GL indicating that we can be confident of a role for GI and GL as causal factors contributing to incident T2D. In addition, neither dietary fiber nor cereal fiber nor wholegrain were found to be reliable or effective surrogate measures of GI or GL. Finally, our cost-benefit analysis suggests food and nutrition advice favors lower GI or GL and would produce significant potential cost savings in national healthcare budgets. The high confidence in causal associations for incident T2D is sufficient to consider inclusion of GI and GL in food and nutrient-based recommendations.
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Carbohydrate nutrition variables and risk of disability in instrumental activities of daily living.
Gopinath, B, Flood, VM, Burlutksy, G, Liew, G, Mitchell, P
European journal of nutrition. 2019;58(8):3221-3228
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In older adults, maintaining independence is determined by the ability to carry out activities of daily living (ADL), such as bathing and walking. Certain features of carbohydrate-rich foods known as the glycaemic index (GI), and glycaemic load (GL) have been implicated in the development of obesity, diabetes, and cardiovascular disease. Other aspects of carbohydrate quality such as fibre intake have been shown to influence the risk of chronic diseases that are more common with ageing. This prospective study aimed to examine the association between the GI and GL of foods consumed, intakes of carbohydrates and fibre, and the ability to perform ADL in older adults. A total of 844 participants from the Blue Mountains Eye Study in Australia, aged 60 years or older were examined from 2002-2004 to 2007-2009. Dietary information was collected using a food-frequency questionnaire, and functional status was assessed using an activities of daily living scale. Participants who reported moderate consumption of dietary fibre (19.1g to 29.6g fibre per day) had a lower risk of experiencing instrumental ADL (IADL) disability compared with those in the lowest group of fibre consumption (19g fibre or less per day); that is, they were more likely to be able to use the telephone, get to places out of walking distance, do housework, take their own medications, and handle money at the 5-year follow-up. There was no added benefit for fibre intake above 19.6g per day. Other baseline carbohydrate nutrition variables, including GI, GL, and total carbohydrate intake, were not associated with ADL disability over the 5 years. The researchers concluded that these findings could inform the development of targeted intervention strategies to encourage a greater intake of fibre-rich foods in older adults, potentially preserving or delaying further deterioration in physical functioning.
Abstract
PURPOSE We aimed to examine the prospective association between dietary glycemic index (GI) and glycemic load (GL) of foods consumed, intakes of carbohydrates and fiber, and the ability to perform activities of daily living (ADL) in older adults. METHODS A total of 844 participants from the Blue Mountains Eye Study aged 60 years or older were examined from 2002-2004 to 2007-2009. Dietary information was collected using a validated, semi-quantitative food-frequency questionnaire. The Older Americans Resources and Services activities of daily living scale were administered to assess the functional status of participants. Multivariable logistic regression analysis was performed. RESULTS After multivariable adjustment, participants who were in the second and third quartiles of energy-adjusted total fiber intake compared to those in the first quartile of intake (reference group) at baseline had reduced risk of incident impaired instrumental activities of daily living (IADL) 5 years later: OR, 0.39 (95% CI 0.22-0.70) and OR 0.54 (95% CI 0.30-0.95), respectively. Analyses that involved dichotomized total fiber intake showed that participants in the upper three quartiles of total fiber intake (> 19 g/day), compared to those in the lowest quartile of intake (≤ 19 g/day) or reference group, had reduced IADL disability risk 5 years later: OR 0.49 (95% CI 0.31-0.79). Non-significant associations were observed with total carbohydrates, GI, and GL and with risk of impaired total and basic ADL at 5-year follow-up. CONCLUSIONS Habitual fiber consumption might be beneficial in leading to improved health status subserving performance of instrumental daily activities, needed to function in the community.
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Changes in Eating Behaviors of Children with Obesity in Response to Carbohydrate-Modified and Portion-Controlled Diets.
Kirk, S, Woo, JG, Brehm, B, Daniels, SR, Saelens, BE
Childhood obesity (Print). 2017;13(5):377-383
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Paediatric obesity has been shown to be managed most effectively when interventions with multiple components, such as dietary changes, physical activity, supportive parental involvement, and behavioural strategies are included. The aim to the study was to evaluate whether baseline or changes in psychological dimensions of eating behaviours could account for variability in weight status outcomes. For this study, children aged between 7 – 12 years with a fasting blood glucose level of ≤100mg/dl and with a BMI z-score of 1.60 – 2.65 were recruited. The participants were randomly assigned to one of the three diet groups (low carbohydrate, reduced glycaemic load or portion-controlled diet). The study results show that eating behaviours improved significantly with all diets, and increased cognitive restraint and decreased hunger were sustained at 12 months. Disinhibition also remained significantly lower at 12 months for the reduced glycaemic load group. Authors conclude that targeting diets to youth with obesity who have specific characteristics such as sex, race, and/or lower baseline hunger or higher baseline cognitive restraint scores may lead to better outcomes.
Abstract
OBJECTIVE This study's objective was to determine whether two distinct carbohydrate (CHO)-modified diets and a standard portion-controlled (PC) diet differentially impacted children's eating behaviors and whether eating behavior scores predicted lower BMI among children with obesity. METHODS Children (n = 102) aged 7-12 years with obesity were randomly assigned to a 12-month intervention of a low-carbohydrate (LC), reduced glycemic load (RGL), or standard PC diet. The Three-Factor Eating Questionnaire (TFEQ) was completed at baseline, 3, 6, and 12 months by parents to characterize their child's hunger (H), disinhibition (D), and cognitive restraint (CR). Baseline and follow-up TFEQ scores by diet were evaluated relative to BMI status over time. RESULTS All diet groups showed increased CR and decreased H and D from baseline to 3 months, with differences from baseline remaining at 12 months for CR and H. Lower BMI status during study follow-up was associated with different TFEQ scores by diet group (LC and RGL: higher CR; PC: lower H), adjusting for sex, age, and race. Higher CR at follow-up was predicted by race and higher baseline CR; only lower H at baseline predicted lower H at follow-up. CONCLUSION Eating behaviors improved significantly with all diets during the initial 3 months; higher CR and lower H were sustained at treatment's end. BMI outcomes were associated with different eating behaviors in CHO-modified diet groups compared with PC diets. Targeting diets of children with obesity with specific baseline characteristics may lead to improved outcomes.
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Dietary acrylamide and cancer risk: an updated meta-analysis.
Pelucchi, C, Bosetti, C, Galeone, C, La Vecchia, C
International journal of cancer. 2015;136(12):2912-22
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Acrylamide is formed in a variety of foods, and some evidence suggests it may cause cancer. The aim of this study was to update their quantitative meta-analysis on dietary acrylamide intake and cancer risk. The study is a meta-analysis based on systemic-literature focusing on the estimate of total dietary acrylamide. A total of 32 publications were reviewed. Results indicate that there is a lack of association between dietary acrylamide and most cancer sites. However, there is a potential small increase in the risk between high levels of acrylamide intake and kidney, endometrial and ovarian cancer in non-smoking women. Authors conclude that dietary acrylamide is not related to the risk of most common cancers.
Abstract
The debate on the potential carcinogenic effect of dietary acrylamide is open. In consideration of the recent findings from large prospective investigations, we conducted an updated meta-analysis on acrylamide intake and the risk of cancer at several sites. Up to July 2014, we identified 32 publications. We performed meta-analyses to calculate the summary relative risk (RR) of each cancer site for the highest versus lowest level of intake and for an increment of 10 µg/day of dietary acrylamide, through fixed-effects or random-effects models, depending on the heterogeneity test. Fourteen cancer sites could be examined. No meaningful associations were found for most cancers considered. The summary RRs for high versus low acrylamide intake were 0.87 for oral and pharyngeal, 1.14 for esophageal, 1.03 for stomach, 0.94 for colorectal, 0.93 for pancreatic, 1.10 for laryngeal, 0.88 for lung, 0.96 for breast, 1.06 for endometrial, 1.12 for ovarian, 1.00 for prostate, 0.93 for bladder and 1.13 for lymphoid malignancies. The RR was of borderline significance only for kidney cancer (RR = 1.20; 95% confidence interval, CI, 1.00-1.45). All the corresponding continuous estimates ranged between 0.95 and 1.03, and none of them was significant. Among never-smokers, borderline associations with dietary acrylamide emerged for endometrial (RR = 1.23; 95% CI, 1.00-1.51) and ovarian (RR = 1.39; 95% CI, 0.97-2.00) cancers. This systematic review and meta-analysis of epidemiological studies indicates that dietary acrylamide is not related to the risk of most common cancers. A modest association for kidney cancer, and for endometrial and ovarian cancers in never smokers only, cannot be excluded.
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Risk factors for pancreatic cancer: a summary review of meta-analytical studies.
Maisonneuve, P, Lowenfels, AB
International journal of epidemiology. 2015;44(1):186-98
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Pancreatic cancer (PC) is one of the four or five most common causes of cancer mortality in developed countries. The aim of this review was to summarize results from pooled analyses and meta-analyses to estimate the fraction of PCs attributable to many different risk factors. A comprehensive review of the literature was carried out by searching for meta-analytical studies on the association between specific risk factors and PC risk or multiple cancer sites. Results indicate that PC has a multifactorial aetiology. All identified factors can be combined into a specific aetiological (the philosophy or study of causation) pathway for PC. The main pathways include insulin resistance (central adiposity, diabetes, metabolic syndrome), inflammation (tobacco, alcohol, pancreatitis), DNA damage (tobacco, red meat) and haemostasis (blood group, history of thrombosis). Authors conclude that about two-thirds of the major risk factors associated with PC are potentially modifiable, affording a unique opportunity for preventing one of our deadliest cancers.
Abstract
BACKGROUND The aetiology of pancreatic cancer (PC) has been extensively studied and is the subject of numerous meta-analyses and pooled analyses. We have summarized results from these pooled and meta-analytical studies to estimate the fraction of PCs attributable to each of the identified risk factors. METHODS Using a comprehensive strategy, we retrieved 117 meta-analytical or pooled reports dealing with the association between specific risk factors and PC risk. We combined estimates of relative risk and estimates of exposure to calculate the fraction of PCs caused or prevented by a particular exposure. RESULTS Tobacco smoking ('strong' evidence) and Helicobacter pylori infection ('moderate' evidence) are the major risk factors associated with PC, with respective estimated population attributable fractions of 11-32% and 4-25%. The major protective factors are history of allergy ('strong' evidence) and increasing fruit or folate intake ('moderate' evidence), with respective population preventable fractions of 3-7% and 0-12%. CONCLUSIONS We summarized results of 117 meta-analytical or pooled data reports dealing with 37 aetiological exposures, to obtain robust information about the suspected causes of PC. By combining these estimates with their prevalences in the population, we calculated population attributable or population preventable fractions. About two-thirds of the major risk factors associated with PC are potentially modifiable, affording a unique opportunity for preventing one of our deadliest cancers.