Prospective study of self-reported diabetes and risk of upper gastrointestinal cancers

Diabetes Mellitus and Gastric Cancer: Correlation and Potential Mechanisms

This review summarizes the correlation between diabetes mellitus (DM) and gastric cancer (GC) from the perspectives of epidemiology, drug use, and potential mechanisms. The association between DM and GC is inconclusive, and the positive direction of the association reported in most published meta-analyses suggests that DM may be an independent risk factor for GC. Many clinical investigations have shown that people with DM and GC who undergo gastrectomy may have better glycemic control. The potential link between DM and GC may involve the interaction of multiple common risk factors, such as obesity, hyperglycemia and hyperinsulinemia, H. pylori infection, and the use of metformin. Although in vitro and in vivo data support that H. pylori infection status and metformin can influence GC risk in DM patients, there are conflicting results. Patient survival outcomes are influenced by multiple factors, so further research is needed to identify the patients who may benefit.

Circulating hormones and risk of gastric cancer by subsite in three cohort studies

BACKGROUND

Obesity has been positively associated with gastric cancer. Excess fat impacts hormones, which have been implicated in carcinogenesis. We investigated obesity-related hormones and cardia gastric cancer (CGC) and non-cardia gastric cancer (NCGC) risk.

METHODS

Nested case-control studies were conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort (61 CGCs, and 172 NCGCs and matched controls) and the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) study (100 CGCs and 65 NCGCs and matched controls); serum hormones were measured. In UK-Biobank (n = 458,713), we included 137 CGCs and 92 NCGCs. Sex-specific analyses were conducted. For EPIC and ATBC, odds ratios (ORs), and for UK-Biobank hazard ratios (HRs), were estimated using conditional logistic regression and Cox regression, respectively.

RESULTS

Insulin-like growth-factor-1 was positively associated with CGC and NCGC in EPIC men (ORper 1-SD increase 1.94, 95% CI 1.03-3.63; ORper 1-SD increase 1.63, 95% CI 1.05-2.53, respectively), with similar findings for CGC in UK-Biobank women (HRper 1-SD increase 1.76, 95% CI 1.08-2.88). Leptin in EPIC men and C-peptide in EPIC women were positively associated with NCGC (ORT3 vs. T1 2.72, 95% CI 1.01-7.34 and ORper 1-SD increase 2.17, 95% CI 1.19-3.97, respectively). Sex hormone-binding globulin was positively associated with CGC in UK-Biobank men (HRper 1-SD increase 1.29, 95% CI 1.02-1.64). Conversely, ghrelin was inversely associated with NCGC among EPIC and ATBC men (ORper 1-SD increase 0.53, 95% CI 0.34-0.84; ORper 1-SD increase 0.22, 95% CI 0.10-0.50, respectively). In addition, dehydroepiandrosterone was inversely associated with CGC in EPIC and ATBC men combined.

CONCLUSIONS

Some obesity-related hormones influence CGC and NCGC risk.

Cancer and diabetes co-occurrence: A national study with 44 million person-years of follow-up

The number of new cases of cancer is increasing each year, and rates of diabetes mellitus are also increasing dramatically over time. It is not an unusual occurrence for an individual to have both cancer and diabetes at the same time, given they are both individually common, and that one condition can increase the risk of the other. In this manuscript, we use national-level diabetes (Virtual Diabetes Register) and cancer (New Zealand Cancer Registry) data on nearly five million individuals over 44 million person-years of follow-up to examine the occurrence of cancer amongst a national prevalent cohort of patients with diabetes. We completed this analysis separately by cancer for the 24 most commonly diagnosed cancers in Aotearoa New Zealand, and then compared the occurrence of cancer among those with diabetes to those without diabetes. We found that the rate of cancer was highest amongst those with diabetes for 21 of the 24 most common cancers diagnosed over our study period, with excess risk among those with diabetes ranging between 11% (non-Hodgkin's lymphoma) and 236% (liver cancer). The cancers with the greatest difference in incidence between those with diabetes and those without diabetes tended to be within the endocrine or gastrointestinal system, and/or had a strong relationship with obesity. However, in an absolute sense, due to the volume of breast, colorectal and lung cancers, prevention of the more modest excess cancer risk among those with diabetes (16%, 22% and 48%, respectively) would lead to a substantial overall reduction in the total burden of cancer in the population. Our findings reinforce the fact that diabetes prevention activities are also cancer prevention activities, and must therefore be prioritised and resourced in tandem.

The Association between the Risk of Esophageal Cancer and Type 2 Diabetes Mellitus: An Updated Meta-Analysis

Background

A large amount of publications had reported the association between incidence of esophageal cancer (EC) and type 2 diabetes mellitus (T2DM) in the past decade. However, those papers' results are inconsistent on relationships between T2DM the incidence of EC. Therefore, the objective of this meta-analysis was to determine the relationship between T2DM and the risk of EC (including 2 histological types, esophageal adenocarcinoma [EADC] and esophageal squamous cell carcinoma [ESCC]).

Method

We finally extracted 19 articles though Pubmed, Embased, and Cochrane library. Those identify extraction date including 14,312 cases and 24,959,067 control records and then mixed the relative risks (RRs) and corresponding 95% confidence intervals (95%CIs) through STATA.

Results

We observed that there are significantly positive correlation between T2DM and EC risk (RR = 1.28, 95% CI: 1.05-1.57, P = 0.015).Also, our study showed positive correlation between T2DM and EADC (esophageal adenocarcinoma) risk (RR = 1.28, 95% CI: 1.05-1.57, P < 0.001). What's more, subgroup analysis based on ethnicity represented the Caucasian is more susceptible to EC (RR = 1.28 ,95% CI: 1.10-1.49, P = 0.001).

Conclusion

Those results offer a recent epidemiological and integrated evidence to ascertain the correlations between T2DM and incidence of EC. Those results take public health implications on preventing T2DM and then depress the occurrence of EC. Our study also provides referenced information for the prevention. However, some data is still insufficient, and more research should be carried out.

The association between diabetes and gastric cancer: results from the Stomach Cancer Pooling Project Consortium

BACKGROUND

Prior epidemiologic studies on the association between diabetes and gastric cancer risk provided inconclusive findings, while traditional, aggregate data meta-analyses were characterized by high between-study heterogeneity.

OBJECTIVE

To investigate the association between type 2 diabetes and gastric cancer using data from the 'Stomach Cancer Pooling (StoP) Project', an international consortium of more than 30 case-control and nested case-control studies, which is large and provides harmonized definition of participants' characteristics across individual studies. The data have the potential to minimize between-study heterogeneity and provide greater statistical power for subgroup analysis.

METHODS

We included 5592 gastric cancer cases and 12 477 controls from 14 studies from Europe, Asia, North America, and South America in a two-stage individual-participant data meta-analysis. Random-effect models were used to estimate summary odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) by pooling study-specific ORs.

RESULTS

We did not find an overall association between diabetes and gastric cancer (pooled OR = 1.01, 95% CI, 0.94-1.07). However, the risk of cardia gastric cancer was significantly higher among individuals with type 2 diabetes (OR = 1.16, 95% CI, 1.02-1.33). There was no association between diabetes and gastric cancer risk in strata of Helicobacter pylori infection serostatus, age, sex, BMI, smoking status, alcohol consumption, fruit/vegetable intake, gastric cancer histologic type, and source of controls.

CONCLUSION

This study provides additional evidence that diabetes is unrelated to gastric cancer overall but may be associated with excess cardia gastric cancer risk.

Haemoglobin A1c and serum glucose levels and risk of gastric cancer: a systematic review and meta-analysis

Background

This systematic review and meta-analysis examined associations between serum levels of haemoglobin A1c (HbA1c) and glucose and the risk of gastric cancer.

Methods

MEDLINE, Embase, and Cochrane Library were searched for studies examining associations between serum levels of HbA1c or glucose and the risk of gastric cancer. Inclusion of studies, quality assessment, and data extraction were conducted independently by two authors. Pooled hazard ratios (HR) with 95% confidence intervals (CI) were synthesised using random-effects models. Cochran’s Q test and I² statistic were used to assess heterogeneity.

Results

Among 3473 identified studies, 12 were included. Of these, 5 studies examined HbA1c levels and 7 studies examined serum glucose levels. Serum HbA1c levels >6% were associated with an increased risk of gastric cancer (HR 1.36, 95% CI 1.06–1.74). When compared with the lowest glucose categories, the highest glucose categories were associated with a borderline increased risk of gastric cancer (HR 1.11, 95% CI 0.98–1.26). In subgroup analyses, studies that adjusted for Helicobacter pylori infection indicated stronger associations between elevated HbA1c levels and gastric cancer (HR 2.08, 95% CI 1.46–2.98) than those without such adjustment (HR 1.10, 95% CI 0.91–1.32).

Conclusions

Long-standing poor glycaemic control may increase the risk of gastric cancer.

Registration number

PROSPERO CRD42020157453.

Diabetes mellitus promoted lymph node metastasis in gastric cancer: a 15-year single-institution experience

Background:

Previous studies have revealed that diabetes mellitus (DM) promotes disease progress of gastric cancer (GC). This study aimed to further investigating whether DM advanced lymph nodes (LNs) metastasis in GC.

Methods:

The clinicopathologic data of GC patients with >15 examined LN (ELN) between October 2004 and December 2019 from a prospectively maintained database were included. The observational outcomes included the number (N3b status) and anatomical distribution (N3 stations) of metastatic LN (MLN).

Results:

A total of 2142 eligible patients were included in the study between October 2004 and December 2019. N3 stations metastasis (26.8% in DM vs. 19.3% in non-DM, P = 0.026) and N3b status (18.8% in DM vs. 12.8% in non-DM, P = 0.039) were more advanced in the DM group, and multivariate logistic regression analyses confirmed that DM was an independent factor of developing N3 stations metastasis (odds ratio [OR] = 1.771, P = 0.011) and N3b status (OR = 1.752, P = 0.028). Also, multivariate analyses determined DM was independently associated with more MLN (β = 1.424, P = 0.047). The preponderance of N3 stations metastasis (DM vs. non-DM, T1–2: 2.2% vs. 4.9%, T3: 29.0% vs. 20.3%, T4a: 38.9% vs. 25.8%, T4b: 50.0% vs. 36.6%; ELN16–29: 8.6% vs. 10.4%, ELN30–44: 27.9% vs. 20.5%, ELN ≥ 45: 37.7% vs. 25.3%), N3b status (DM vs. non-DM, T1–2: 0% vs. 1.7%, T3: 16.1% vs. 5.1%, T4a: 27.8% vs. 19.1%, T4b: 44.0% vs. 28.0%; ELN16–29: 8.6% vs. 7.9%, ELN30–44: 18.0% vs. 11.8%, ELN ≥ 45: 26.4% vs. 17.3%), and the number of MLN (DM vs. non-DM, T1–2: 0.4 vs. 1.1, T3: 8.6 vs. 5.2, T4a: 9.7 vs. 8.6, T4b: 17.0 vs. 12.8; ELN16–29: 3.6 vs. 4.6, ELN30–44: 5.8 vs. 5.5, ELN ≥ 45: 12.0 vs. 7.7) of DM group increased with the advancement of primary tumor depth stage and raising of ELN.

Conclusions:

DM was an independent risk factor for promoting LN metastasis. The preponderance of LN involvement in the DM group was aggravated with the advancement of tumor depth.

Population Attributable Risks of Subtypes of Esophageal and Gastric Cancers in the United States

INTRODUCTION

To help target preventive strategies, we estimated US population attributable risks (PARs) of demographic and potentially modifiable risk factors for esophageal squamous cell carcinoma (ESCC), esophageal adenocarcinoma (EAC), gastric cardia adenocarcinoma (GCA), and gastric noncardia adenocarcinoma (GNCA).

METHODS

We prospectively examined the associations for risk factors and these cancers in 490,605 people in the National Institutes of Health-the American Association of Retired Persons Diet and Health cohort Diet and Health Study cohort from 1995 to 2011. Exposures were obtained from the baseline questionnaire. Diagnoses of gastroesophageal reflux disease were extracted for a subset of eligible National Institutes of Health-the American Association of Retired Persons Diet and Health cohort subjects through linkage to Medicare and then multiply imputed for non-Medicare-eligible subjects. Hazard ratios were calculated using multivariable-adjusted Cox proportional hazards regression. Adjusted population attributable risks were calculated for the US population aged 50-71 years by combining the hazard ratios with the estimated joint distribution of risk factor prevalence from the 2015 National Health Interview Survey.

RESULTS

Smoking remained the most important risk factor for ESCC and was estimated to cause more than 1/3 of EAC and GCA and 1/10 of GNCA. Obesity and gastroesophageal reflux disease were associated with more than 1/2 of EAC and 1/3 of GCA. Compared with each lowest-risk level category, common risk factors were estimated to be associated with 73.7% of ESCC (95% confidence interval [CI]: 62.1%-85.4%), 70.3% of EAC (95% CI: 64.4%-76.2%), 69.3% of GCA (95% CI: 61.0%-77.7%), and 33.6% of GNCA (95% CI: 21.7%-45.5%).

DISCUSSION

These factors accounted for a large proportion of esophageal and gastric cancers in the United States, highlighting opportunities for education and intervention to reduce the burden of these highly fatal cancers.

The Relationship between Diabetes Mellitus and Gastric Cancer and the Potential Benefits of Metformin: An Extensive Review of the Literature

The objective of this review is to summarize the findings of published research that investigated the relationship between diabetes mellitus and gastric cancer (GCa) and the potential benefits of metformin on GCa. Related literature has been extensively reviewed, and findings from studies investigating the relationship between diabetes mellitus and GCa suggest that hyperglycemia, hyperinsulinemia and insulin resistance are closely related to the development of GCa. Although not supported by all, most observational studies suggest an increased risk of GCa in patients with type 2 diabetes mellitus, especially in women and in Asian populations. Incidence of second primary malignancy diagnosed after GCa is significantly higher in diabetes patients. Diabetes patients with GCa may have more complications after gastrectomy or chemotherapy and they may have a poorer prognosis than patients with GCa but without diabetes mellitus. However, glycemic control may improve in the diabetes patients with GCa after receiving gastrectomy, especially after procedures that bypass the duodenum and proximal jejunum, such as Roux-en-Y gastric bypass or Billroth II reconstruction. The potential links between diabetes mellitus and GCa may involve the interactions with shared risk factors (e.g., obesity, hyperglycemia, hyperinsulinemia, insulin resistance, high salt intake, smoking, etc.), Helicobacter pylori (HP) infection, medications (e.g., insulin, metformin, statins, aspirin, proton pump inhibitors, antibiotics, etc.) and comorbidities (e.g., hypertension, dyslipidemia, vascular complications, heart failure, renal failure, etc.). With regards to the potential benefits of metformin on GCa, results of most observational studies suggest a reduced risk of GCa associated with metformin use in patients with T2DM, which can be supported by evidence derived from many in vitro and animal studies. Metformin use may also reduce the risk of HP infection, an important risk factor of GCa. In patients with GCa, metformin users may have improved survival and reduced recurrence. More studies are required to clarify the pathological subtypes/anatomical sites of GCa associated with type 2 diabetes mellitus or prevented by metformin, to confirm whether GCa risk can also be increased in patients with type 1 diabetes mellitus and to explore the possible role of gastric microbiota in the development of GCa.

Proteomics Analysis of Gastric Cancer Patients with Diabetes Mellitus

Proteomics is a powerful approach to study the molecular mechanisms of cancer. In this study, we aim to characterize the proteomic profile of gastric cancer (GC) in patients with diabetes mellitus (DM) type 2. Forty GC tissue samples including 19 cases from diabetic patients and 21 cases from individuals without diabetes (control group) were selected for the proteomics analysis. Gastric tissues were processed following the single-pot, solid-phase-enhanced sample preparation approach-SP3 and enzymatic digestion with trypsin. The resulting peptides were analyzed by LC-MS Liquid Chromatography-Mass Spectrometry (LC-MS). The comparison of protein expression levels between GC samples from diabetic and non-diabetic patients was performed by label-free quantification (LFQ). A total of 6599 protein groups were identified in the 40 samples. Thirty-seven proteins were differentially expressed among the two groups, with 16 upregulated and 21 downregulated in the diabetic cohort. Statistical overrepresentation tests were considered for different annotation sets including the Gene Ontology(GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Reactome, and Disease functional databases. Upregulated proteins in the GC samples from diabetic patients were particularly enriched in respiratory electron transport and alcohol metabolic biological processes, while downregulated proteins were associated with epithelial cancers, intestinal diseases, and cell-cell junction cellular components. Taken together, these results support the data already obtained by previous studies that associate diabetes with metabolic disorders and diabetes-associated diseases, such as Alzheimer's and Parkinson's, and also provide valuable insights into seven GC-associated protein targets, claudin-3, polymeric immunoglobulin receptor protein, cadherin-17, villin-1, transglutaminase-2, desmoglein-2, and mucin-13, which warrant further investigation.

Upper Gastrointestinal Cancer in China: Spatial Epidemiologic Evidence from Screening Areas

Upper gastrointestinal cancer (UGIC) including esophageal cancer and gastric cancer, which has been a significant burden in China. Few studies have explored the spatial pattern and association of incidence and mortality using nationwide data. This study aims to explore the spatial pattern and association of incidence and mortality between esophageal cancer and gastric cancer, and identify high-risk areas of the cancers to provide scientific evidence for tailoring endoscopic screening programs. We collected UGIC data in 2014 from a National Cancer Report, and then adopted methods of correlation analysis and spatial statistics to identify high-risk areas on the cancers and to explore the pattern. The results show a spatial autocorrelation on the spatial distribution of incidence and mortality of esophageal and gastric cancers, and the relative risks were from 2.52 (95% CI (confidence interval), 2.37-2.67; P < 0.001) to 3.80 (95% CI, 3.46-4.18; P < 0.001) in primary risk areas, respectively. Moreover, esophageal cancer shows an upward and then downward trend from west to east, and from south to north, yet gastric cancer exhibits an upward and then downward trend only from south to north. This study indicates habitants in overlapping risk areas have heavier cancer burdens, and suggests esophageal cancer and gastric cancer have a significant correlation. Therefore, more endoscopic screening attention should focus on overlapping risk areas.

Diabetes in relation to Barrett's esophagus and adenocarcinomas of the esophagus: A pooled study from the International Barrett's and Esophageal Adenocarcinoma Consortium

BACKGROUND

Diabetes is positively associated with various cancers, but its relationship with tumors of the esophagus/esophagogastric junction remains unclear.

METHODS

Data were harmonized across 13 studies in the International Barrett's and Esophageal Adenocarcinoma Consortium, comprising 2309 esophageal adenocarcinoma (EA) cases, 1938 esophagogastric junction adenocarcinoma (EGJA) cases, 1728 Barrett's esophagus (BE) cases, and 16,354 controls. Logistic regression was used to estimate study-specific odds ratios (ORs) and 95% CIs for self-reported diabetes in association with EA, EGJA, and BE. Adjusted ORs were then combined using random-effects meta-analysis.

RESULTS

Diabetes was associated with a 34% increased risk of EA (OR, 1.34; 95% CI, 1.00-1.80; I2  = 48.8% [where 0% indicates no heterogeneity, and larger values indicate increasing heterogeneity between studies]), 27% for EGJA (OR, 1.27; 95% CI, 1.05-1.55; I2  = 0.0%), and 30% for EA/EGJA combined (OR, 1.30; 95% CI, 1.06-1.58; I2  = 34.9%). Regurgitation symptoms modified the diabetes-EA/EGJA association (P for interaction = .04) with a 63% increased risk among participants with regurgitation (OR, 1.63; 95% CI, 1.19-2.22), but not among those without regurgitation (OR, 1.03; 95% CI, 0.74-1.43). No consistent association was found between diabetes and BE.

CONCLUSIONS

Diabetes was associated with increased EA and EGJA risk, which was confined to individuals with regurgitation symptoms. Lack of an association between diabetes and BE suggests that diabetes may influence progression of BE to cancer.

Sarcopenia and Sarcopenic Obesity as Novel Risk Factors for Gastric Carcinogenesis: A Health Checkup Cohort Study

Background: Insulin resistance, the primary mechanism of metabolic syndrome, promotes gastric carcinogenesis. Metabolic syndrome is associated with sarcopenia. We aimed to investigate the association between sarcopenia and gastric carcinogenesis, including precancerous conditions such as atrophic gastritis (AG), intestinal metaplasia (IM), and dysplasia.

Methods: The study included adult patients who underwent gastroduodenoscopy at a checkup center. AG and IM were evaluated using endoscopy. Based on muscle mass, sarcopenia was defined as a skeletal muscle index <1 standard deviation below the sex-specific mean for healthy adults aged 20–39 years (cutoff point: 29.3% for males and 26.7% for females). Obesity was defined as a body mass index (BMI) ≥25 kg/m² according to the Asia-Pacific criteria. Sarcopenic obesity was defined as a combination of sarcopenia and obesity. The association between gastric carcinogenesis and sarcopenia was evaluated.

Results: Among 8,356 enrolled participants, 0.14 and 42.5% were diagnosed with gastric cancer and precancerous conditions, respectively. Approximately 41.7% of gastric cancer patients and 16.9% of patients with precancerous conditions were diagnosed with sarcopenia. Both sarcopenic obesity (odds ratio [OR] = 4.139, P = 0.016) and diabetes mellitus (DM) (OR = 5.152, P = 0.005) were significantly associated with gastric cancer. Sarcopenia, DM, hypertension, dyslipidemia, Helicobacter pylori infection, smoking, and alcohol consumption were significantly associated with precancerous conditions.

Conclusions: Sarcopenia and sarcopenic obesity were associated with gastric carcinogenesis and may be novel risk factors for gastric carcinogenesis.

Diabetes and cancer: A comprehensive review

Diabetes mellitus (DM) is a common worldwide endocrine disorder characterized by hyperglycemia resulting from defects in insulin secretion and insulin action or both. A number of clinical studies have investigated diabetes and its causal relation with neoplasm. Several epidemiological studies have found that diabetic patients have an increased risk of different types of cancers, for example liver, pancreas, gastric (stomach), colorectum, kidney, and breast, and it is predicted that hyperglycemic state observed in diabetic milieu enhances the cancer risk in prediabetic and diabetic individuals. To explore the strength of evidence and biases in the claimed associations between type 2 DM (T2DM) and risk of developing cancer, an umbrella review of the evidence across published meta-analyses or systematic reviews is performed. The concurrence of T2DM with the growing burden of cancer globally has generated interest in defining the epidemiological and biological relationships between these medical conditions. Through this review, it was found that diabetes could be related to cancer. Yet, the results from most of the studies are obscure and conflicting and need a robust research so that the link between diabetes and cancer could be firmly and impeccably documented.

Metformin use and risk of gastric adenocarcinoma in a Swedish population-based cohort study

Background

Whether or not the use of metformin decreases the risk of gastric adenocarcinoma is unclear.

Methods

This was a population-based cohort study in 2005–2015. Associations between metformin use and gastric non-cardia and cardia adenocarcinomas were examined within two cohorts; a diabetes cohort of participants using anti-diabetes medications, and a matched cohort of common-medication users, where metformin non-users were frequency matched (10:1) with metformin users for sex and age. Multivariable Cox proportional hazard regression analyses provided hazard ratios (HR) and 95% confidence intervals (CI), adjusting for sex, age, calendar year, comorbidity, Helicobacter pylori eradication treatment, use of non-steroidal anti-inflammatory drugs or aspirin and use of statins.

Results

During the follow-up for a median of 5.8 years, 892 (0.1%) participants in the diabetes cohort and 6395 (0.1%) participants in the matched cohort of common-medication users developed gastric adenocarcinoma. Metformin users had no significantly decreased risk of gastric non-cardia adenocarcinoma (diabetes cohort: HR 0.93, 95% CI 0.78–1.12; matched cohort: HR 1.30, 95% CI 1.18–1.42) or cardia adenocarcinoma (diabetes cohort: HR 1.49, 95% CI 1.09–2.02; matched cohort: HR 1.58, 95% CI 1.38–1.81) compared with non-users in both cohorts.

Conclusions

This cohort study with <10 years of follow-up suggests metformin use may not prevent gastric adenocarcinoma.

Diabetes Increases Risk of Gastric Cancer After Helicobacter pylori Eradication: A Territory-Wide Study With Propensity Score Analysis

OBJECTIVE

Whether diabetes mellitus (DM) increases risk of gastric cancer (GC) remains controversial because of inadequate adjustments for important risk factors, including Helicobacter pylori (HP) infection status, concomitant medication use, and cancer site. We investigated whether type 2 DM increased risk of GC in patients after they received treatment for HP infection.

RESEARCH DESIGN AND METHODS

This was a territory-wide cohort study of patients aged ≥45 years who had received clarithromycin-based triple therapy for HP infection between 2003 and 2012 in Hong Kong. Data were retrieved from a public electronic health database. Observation started from receipt of therapy for HP infection to GC diagnosis, death, or the end of the study (December 2015). Exclusion criteria included type 1 DM, GC diagnosed within the 1st year of HP therapy, prior GC or gastrectomy, and retreatment for HP infection. The adjusted hazard ratio (aHR) of GC with type 2 DM was calculated by using a Cox model that adjusted for 20 covariates (age, sex, comorbidities, and medications) through propensity score regression.

RESULTS

During a median follow-up of 7.1 years (interquartile range 4.8-9.3 years), 153 of 46,460 patients (0.33%) developed GC at a median age of 72.4 years. Type 2 DM was associated with an increased risk of GC (aHR 1.73 [95% CI 1.08-2.79]). Stratified analysis showed an increase in risk for cardia cancer only (aHR 3.40 [95% CI 1.45-7.97]) and in those with suboptimal DM control (time-weighted mean HbA_1c ≥6.0% [42 mmol/mol]; aHR 1.68 [95% CI 1.07-2.63]).

CONCLUSIONS

Type 2 DM is associated with an increased risk of GC among patients in whom HP was eradicated, in particular gastric cardia cancer and in those with suboptimal DM control.

Prediabetes and diabetes in relation to risk of gastric adenocarcinoma

BACKGROUND

Whether prediabetes or diabetes increases the risk of gastric adenocarcinoma is not clear.

METHODS

This cohort study included 111,198 participants in the Northern Swedish Health and Disease Study. The participants were followed up from November 1985 to April 2017. The exposure to prediabetes or diabetes was assessed by oral glucose tolerance tests and self-reports. The incidence of the outcome gastric adenocarcinoma was identified from the Swedish Cancer Registry. Multivariable Cox regressions were used to analyse the associations between prediabetes or diabetes and the risk of gastric adenocarcinoma, providing hazard ratios (HR) with 95% confidence intervals (CI), with adjustment for sex, age, calendar year, body mass index, tobacco smoking and education level.

RESULTS

Compared with normoglycaemic participants, the risk of gastric adenocarcinoma was not increased among participants with prediabetes (HR 1.07, 95% CI 0.79-1.44), diabetes (HR 0.77, 95% CI 0.46-1.29) or any of these exposures (HR 0.96, 95% CI 0.73-1.27). No associations were identified between prediabetes or diabetes and the risk of gastric adenocarcinoma in stratified analyses or in analyses separating cardia and non-cardia gastric adenocarcinoma.

CONCLUSIONS

This study does not support the hypothesis that prediabetes or diabetes increases the risk of gastric adenocarcinoma.

Association between tooth loss and upper gastrointestinal cancer: A 30-year follow-up of the Linxian Dysplasia Nutrition Intervention Trial Cohort

Background

This prospective study investigated the association between tooth loss and upper gastrointestinal (UGI) cancer mortality in the Linxian Dysplasia Nutrition Intervention Trial Cohort.

Methods

Subjects were categorized into three groups according to age at baseline. No missing teeth and less or greater than median tooth loss in each group was defined as none, moderate, and severe, respectively. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using the Cox proportional hazard model.

Results

Through 30 September 2015, 541 esophageal squamous cell carcinoma (ESCC), 284 gastric cardia carcinoma (GCC), and 77 gastric non‐cardia carcinoma (GNCC) deaths occurred. In the six‐year follow‐up, severe tooth loss was associated with an increased risk of GCC mortality (HR 1.55, 95% CI 1.06–2.18). In the 15‐year follow‐up, moderate tooth loss increased the ESCC mortality risk by 58% (HR 1.58, 95% CI 1.06–2.35), while severe loss increased the GCC mortality risk by 30% (HR 1.30, 95% CI 1.03–1.64). In the 30‐year follow‐up, moderate tooth loss increased the risk of ESCC mortality (HR 1.34, 95% CI 1.01–1.76). In subjects aged < 55 at baseline and men, moderate tooth loss had 53% and 52% higher risks of ESCC mortality (HR_{<55 years} 1.53, 95% CI 1.06–2.05; HRmen 1.52, 95% CI 1.01–2.28). No significant association was observed for GNCC in any subjects or subgroups.

Conclusion

Moderate tooth loss increased the risk of ESCC mortality, particularly in younger subjects and men. Severe tooth loss increased the risk of GCC mortality. Future studies are needed to confirm these findings.

Gastrointestinal cancer incidence in type 2 diabetes mellitus; results from a large population-based cohort study in the UK

BACKGROUND

Patients with type 2 diabetes mellitus (T2DM) have been shown to have higher incidences of liver, pancreatic, and colorectal cancer compared to non-diabetic individuals. Current evidence is conflicting for other gastrointestinal (GI) cancers. Therefore, we aimed to determine incidence rates (IRs) of all GI cancers in patients with and without T2DM.

METHODS

A cohort study was performed using the UK Clinical Practice Research Datalink (1988-2012). A cohort of antidiabetic drug users was matched at baseline to a non-diabetic cohort, by age, sex, and practice. Crude IRs and 95% confidence intervals (95% CI) of GI cancers per 100,000 person-years were calculated stratified by age, sex, and calendar year.

RESULTS

333,438 T2DM and 333,438 non-diabetic individuals were analyzed. IRs of liver (IR 26, 95% CI 24-28 vs. 8.9, 95% CI 7.7-10), pancreatic (IR 65, 95% CI 62-69 vs. 31, 95% CI 28-34), and colon cancer (IR 119, 95% CI 114-124 vs. 109, 95% CI 104-114) were significantly higher in the diabetic compared to the non-diabetic cohort, whereas the IR of oesophageal cancer was significantly lower (IR 41, 95% CI 39-44 vs. 47, 95% CI 44-51). Sex-specific IRs of colon cancer remained significantly higher in men with T2DM, and IRs of esophageal cancer remained significantly lower in women with T2DM.

CONCLUSION

In this study, T2DM patients were shown to have higher crude IRs of liver, pancreatic and colon cancer, but not of gastric, biliary, and rectal cancer. Moreover, the lower observed IRs of oesophageal cancer in diabetic patients warrants further investigation.

Diabetes mellitus and the risk of gastrointestinal cancer in women compared with men: a meta-analysis of cohort studies

Background

The increasing epidemic proportions of diabetes mellitus (DM) are a major cause of premature illness and death. However, whether DM confers the same excess risk of gastrointestinal cancer for women as it does for men remains controversial. The purpose of this study was to estimate the relation between DM and gastrointestinal cancer in women compared with men after accounting for other major risk factors based on cohort studies.

Methods

We performed a meta-analysis of cohort studies published through May 2017 from PubMed, Embase, and the Cochrane Library. Studies with cohort designs were stratified by sex and reported the relation between DM and esophageal cancer (EC), gastric cancer (GC), colorectal cancer (CRC), colon cancer (CC), rectal cancer (RC), hepatocellular carcinoma (HCC), or pancreatic cancer (PC) risk. The ratio of relative risk (RRR) between men and women was employed to measure the sex differences in the relation between DM and gastrointestinal cancer with a random effects model with inverse variance weighting.

Results

We included 38 cohort studies reporting data on 18,060,698 individuals. The pooled RRR indicated DM women was associated with an increased risk of GC (RRR: 1.14; 95%CI: 1.06–1.22; p < 0.001), while the risk of HCC was lower (RRR: 0.88; 95%CI: 0.79–0.99; p = 0.031) as compared with DM men. Further, there was no evidence of sex differences in the RRR between participants who had DM compared with those without DM for EC (p = 0.068), CRC (p = 0.618), and PC (p = 0.976). In addition, the pooled RRR showed a statistically significant association between DM and the risk of CC in women compared with men (RRR: 0.93; 95%CI: 0.86–1.00; p = 0.050), and there was no evidence of sex differences for RC among participants with DM compared to those without DM (p = 0.648). Finally, the sex differences of the comparison between DM and non-DM for gastrointestinal cancer risk at different sites were variable after stratification for different effect estimates.

Conclusions

The findings of this study suggested female-to-male RRR of DM was increased for GC, while reduced for HCC and CC. However, there were no sex differences for the relation between DM and the risk of EC, CRC, PC, and RC.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4351-4) contains supplementary material, which is available to authorized users.

Diabetes mellitus and the risk of gastric cancer: a meta-analysis of cohort studies

Studies examining the relationship between diabetes mellitus (DM) and the risk of gastric cancer incidence or gastric cancer mortality have produced inconsistent results. The purpose of this study was to evaluate the evidence regarding the relationship between DM and subsequent gastric cancer incidence or gastric cancer mortality risk on the basis of cohort studies. A systematic search of articles in PubMed, EmBase, the Cochrane Library, and reference lists was conducted to identify relevant literature. Twenty-two cohort studies reporting data on 8,559,861 participants were included in the study. Overall, participants with DM had little or no change in the risk of gastric cancer, or gastric cancer mortality. There was no evidence of difference in the RR for gastric cancer between men and women. Participants with DM had a non-significant trend towards an increased risk of gastric cancer mortality in men. There was no significant difference between men and women for this relationship. Finally, although subgroup analysis suggested DM was associated with a significant impact on gastric cancer incidence and gastric cancer mortality risk in several specific populations, a significance based on gender difference was not observed. In conclusion, DM might increase the risk of gastric cancer in men when the study used standard incidence/mortality ratio as effect estimate. Further, DM were associated with higher risk of gastric cancer mortality in men if the mean age at baseline less than 55.0 years, used RR or HR as effect estimate, the study adjusted smoking or not, and the study not adjusted alcohol drinking.

Diabetic biomarkers and the risk of proximal or distal gastric cancer

BACKGROUND AND AIM

The role of diabetes mellitus as a risk factor for gastric cancer has been controversial. We studied the association between diabetic biomarkers and the risk of gastric cancer and whether these associations depend on cancer location.

METHODS

In this retrospective cohort study with subjects with negative initial esophagogastroduodenoscopy findings (n = 23 218) during a routine health checkup, we measured fasting glucose and insulin levels, calculated the homeostatic model assessment insulin resistance (HOMA-IR) values, and analyzed the risk of gastric cancer in relation to diabetic biomarker tertiles and the presence of diabetes mellitus.

RESULTS

The incidence rate of gastric cancer was 9.7 per 10 000 person-years during the mean 6.8-year follow up. Patients with diabetes, higher fasting glucose levels, or higher HOMA-IR levels were older; men, current smokers, and heavy alcohol consumers represented larger proportions of these groups. They also had high body mass index and hemoglobin A1c more often. In the multivariate-adjusted Cox regression analyses, the incidence of gastric cancer was not significantly associated with diabetes mellitus or higher diabetic biomarker levels. Compared with normal glucose levels, lower glucose levels were significantly associated with an increased risk of distal gastric cancer. The hazard ratio for fasting glucose level tertile 1 was 2.39 (95% confidence interval, 1.48-3.85) (reference, tertile 2). Lower glucose levels were not associated with a risk of proximal gastric cancer, compared with a normal glucose level.

CONCLUSIONS

Our findings suggest that fasting glucose levels have a different effect on distal and proximal gastric cancers.

Association between diabetes and esophageal cancer, independent of obesity, in the United States Veterans Affairs population

In the past 30 years, the incidence of esophageal adenocarcinoma (EAC) has increased more rapidly than any other cancer in the United States. The prevalence of obesity and diabetes mellitus has drastically increased as well. We explored the potential association between obesity, diabetes mellitus, and EAC. By means of retrospective interrogation of an administrative database from fiscal year 2005-2009, we identified two cohorts. The cancer cohort was defined as patients with adenocarcinoma of the distal esophagus or gastric cardia. The comparison cohort contained patients with gastroesophageal reflux disorder (GERD; diagnosis coupled with a procedure code for fundoplication). Patient data, including demographic measures, diagnoses of obesity, diabetes mellitus, dyslipidemia, alcohol abuse, and nicotine dependence were examined. A logistic regression model identified risk factors for development of EAC. The sample included 2,836 patients identified as having either EAC (1,704) or fundoplication with GERD (1,132). Although slightly higher percentages of the benign cohort were obese, the cancer cohort had more diabetics (30.8% vs. 14.8%; chi-square = 94.5; P < 0.0001). In a logistic regression analysis adjusting for comorbidity and lifestyle factors, diagnosis of diabetes mellitus was significantly associated with esophageal cancer as opposed to GERD without cancer (OR = 2.2; 95% confidence interval [CI] 1.7-2.8). Nicotine dependence was also identified as a risk factor (OR = 1.7; 95% CI 1.4-2.0). We identified a potential association between diabetes mellitus and adenocarcinoma of the esophagus or gastric cardia. This association appears to be independent of obesity. Additionally, nicotine dependence was identified as a risk factor for EAC.

Hyperglycemia Promotes Human Gastric Carcinoma Progression via Aquaporin 3

BACKGROUND

Hyperglycemia plays an important role in the development of gastric carcinoma (GC). Aquaporin 3 (AQP3) is overexpressed in GC and involved in carcinogenesis and progression of GC. Hyperglycemia promotes AQP3 expression in human peritoneal mesothelial cells.

AIMS

To investigate whether hyperglycemia promotes progression of GC via AQP3.

METHODS

We enrolled 978 patients with GC and evaluated the correlation between preoperative fasting plasma glucose and clinicopathological features. AQP3 was detected by immunohistochemistry in human GC specimens. Western blotting and real-time quantitative polymerase chain reaction evaluated changes in AQP3 expression in human GC MGC803 and SGC7901 cells after co-culture with high glucose. Transwell migration and Cell Counting Kit-8 assays were used to determine migration and proliferation of GC cells.

RESULTS

Hyperglycemia (fasting plasma glucose ≥6.1 mM) correlated with tumor size, location, and pTNM stage. AQP3 expression in tumor tissue was associated with fasting plasma glucose levels. High glucose concentration upregulated AQP3 expression in a dose- and time-dependent manner. High glucose concentration promoted GC cell migration markedly, and AQP3 knockdown with siRNA could abolish the increase in cell migration. However, high glucose concentration inhibited cell proliferation, and AQP3 knockdown significantly enhanced the inhibitory effect of high glucose. The ERK and PI3K/AKT signaling pathways were involved in high glucose regulation of AQP3 in human GC cells.

CONCLUSION

Hyperglycemia promotes GC progress via AQP3. This improves our understanding of the mechanism of hyperglycemia-induced carcinogenesis and provides a potential therapeutic strategy for GC.

Obesity and related risk factors in gastric cardia adenocarcinoma

Over recent decades, the incidence of cancers of the gastroesophageal junction, including gastric cardia tumors, has increased markedly. This is a trend that has been well documented, especially in studies from the USA and northern Europe that have also demonstrated a concomitant rise in the ratio of cardia to distal gastric cancers. The rise in the prevalence of gastric cardia adenocarcinoma has been paralleled by the worldwide obesity epidemic, with almost all epidemiological studies reporting increased body mass index and obesity increase the risk of cardia cancer development. However, the strength of this association is less marked than the link between obesity and esophageal adenocarcinoma, and the mechanisms remain poorly understood. Other possible confounders of the relationship between obesity and cardia cancer include the decline in Helicobacter pylori infection and the widespread use of proton pump inhibitors, although these have rarely been controlled for in case-control and cohort studies investigating associations between obesity and cardia cancer. We review these epidemiological trends and discuss proposed mechanisms for the association, drawing attention to controversies over the difficulty of defining cardia cancer. The relative paucity of high-quality epidemiological studies from other regions of the world should prompt further investigation of this issue, especially in populations undergoing rapid socioeconomic change.

CARING (CAncer Risk and INsulin analoGues): the association of diabetes mellitus and cancer risk with focus on possible determinants - a systematic review and a meta-analysis

Background:

Patients suffering from diabetes mellitus (DM) may experience an increased risk of cancer; however, it is not certain whether this effect is due to diabetes per se.

Objective:

To examine the association between DM and cancers by a systematic review and meta-analysis according to the PRISMA guidelines.

Data Sources:

The systematic literature search includes Medline at PubMed, Embase, Cinahl, Bibliotek.dk, Cochrane library, Web of Science and SveMed+ with the search terms: “Diabetes mellitus”, “Neoplasms”, and “Risk of cancer”.

Study Eligibility Criteria:

The included studies compared the risk of cancer in diabetic patients versus non-diabetic patients. All types of observational study designs were included.

Results:

Diabetes patients were at a substantially increased risk of liver (RR=2.1), and pancreas (RR=2.2) cancer. Modestly elevated significant risks were also found for ovary (RR=1.2), breast (RR=1.1), cervix (RR=1.3), endometrial (RR=1.4), several digestive tract (RR=1.1-1.5), kidney (RR=1.4), and bladder cancer (RR=1.1). The findings were similar for men and women, and unrelated to study design. Meta-regression analyses showed limited effect modification of body mass index, and possible effect modification of age, gender, with some influence of study characteristics (population source, cancer- and diabetes ascertainment).

Limitations:

Publication bias seemed to be present. Only published data were used in the analyses.

Conclusions:

The systematic review and meta-analysis confirm the previous results of increased cancer risk in diabetes and extend this to additional cancer sites. Physicians in contact with patients with diabetes should be aware that diabetes patients are at an increased risk of cancer.

Plasma insulin, C-peptide and blood glucose and the risk of gastric cancer: the Japan Public Health Center-based prospective study

To date, the association between diabetes mellitus (DM) and gastric cancer has been controversial, including the underlying mechanism. We investigated the association between plasma diabetic biomarkers (insulin, C-peptide, and blood glucose) and gastric cancer risk. In addition, homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β-cell function (HOMA-β) were calculated. A total of 36,745 subjects aged 40-69 years in the Japan Public Health Center-based prospective study (JPHC) who returned the baseline questionnaire and provided blood samples were followed from 1990 to 2004. In the present analysis, 477 cases and 477 matched controls were used. The odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) for developing gastric cancer were calculated using conditional logistic regression models. Plasma insulin was positively associated with increased risk of gastric cancer; compared to tertile 1, ORs were 1.69 (95% CI = 1.11-2.59) and 2.01 (1.19-3.38) for tertiles 2 and 3, respectively (p for trend = 0.009). In men, C-peptide was also positively associated with a significant risk; corresponding ORs were 1.42 (0.85-2.38) and 1.91 (1.03-3.54), respectively (p for trend = 0.04). These findings were confirmed for blood samples from the fasting group (≥8 hr after a meal). Higher HOMA-IR was also associated with increased risk, whereas no association was observed for blood glucose. Our findings suggest that Japanese population with higher insulin and C-peptide levels derived from insulin resistance have an elevated risk of gastric cancer.

A five-microRNA panel in plasma was identified as potential biomarker for early detection of gastric cancer

BACKGROUND

Circulating microRNAs (miRNAs) have been implicated as novel biomarkers for gastric cancer (GC) diagnosis. However, the mixture of GC subtypes may have led to the inconsistent circulating miRNA profiles, and the clinical performance of circulating miRNAs has not yet been evaluated independently on early detection of GC.

METHODS

A four-phase study was designed with a total of 160 cancer-free controls, 124 patients with gastric non-cardia adenocarcinoma (GNCA) and 36 patients diagnosed gastric cardia adenocarcinoma (GCA). In the discovery phase, we screened the miRNA expression profile in plasma of 40 GNCA patients (stage I) and 40 matched controls by TaqMan low density array (TLDA) chips with pooled samples. Differentially expressed miRNAs were further validated in individual sample using quantitative reverse-transcriptase PCR (qRT-PCR) in the training phase. Subsequently, in an independent validation phase, the identified miRNAs were evaluated in 48 GNCA patients (stage I) and 102 matched controls. Finally, the identified miRNAs were further assessed in an external validation phase including advanced GNCA and GCA patients. Additionally, the expression levels of identified miRNAs were measured in the media of BGC823 and MGC803 cell lines.

RESULTS

Five miRNAs (miR-16, miR-25, miR-92a, miR-451 and miR-486-5p) showed consistently elevated levels in plasma of the GC patients as compared with controls, and were identified to be potential markers for GNCA with area under the receiver operating characteristic (ROC) curves (AUCs) ranging from 0.850 to 0.925 and 0.694 to 0.790 in the training and validation phases, respectively. The five-miRNA panel presented a high diagnostic accuracy for the early-stage GNCA (AUCs=0.989 and 0.812 for the training and validation phases, respectively). Three miRNAs (miR-16, miR-25 and miR-92a) were excreted into the culture media of GC cell lines.

CONCLUSIONS

The five-miRNA panel in plasma may serve as a potential non-invasive biomarker in detecting the early-stage GC.

Diabetes and gastric cancer: The potential links

This article reviews the epidemiological evidence linking diabetes and gastric cancer and discusses some of the potential mechanisms, confounders and biases in the evaluation of such an association. Findings from four meta-analyses published from 2011 to 2013 suggest a positive link, which may be more remarkable in females and in the Asian populations. Putative mechanisms may involve shared risk factors, hyperglycemia, Helicobacter pylori (H. pylori) infection, high salt intake, medications and comorbidities. Diabetes may increase the risk of gastric cancer through shared risk factors including obesity, insulin resistance, hyperinsulinemia and smoking. Hyperglycemia, even before the clinical diagnosis of diabetes, may predict gastric cancer in some epidemiological studies, which is supported by in vitro, and in vivo studies. Patients with diabetes may also have a higher risk of gastric cancer through the higher infection rate, lower eradication rate and higher reinfection rate of H. pylori. High salt intake can act synergistically with H. pylori infection in the induction of gastric cancer. Whether a higher risk of gastric cancer in patients with diabetes may be ascribed to a higher intake of salt due to the loss of taste sensation awaits further investigation. The use of medications such as insulin, metformin, sulfonylureas, aspirin, statins and antibiotics may also influence the risk of gastric cancer, but most of them have not been extensively studied. Comorbidities may affect the development of gastric cancer through the use of medications and changes in lifestyle, dietary intake, and the metabolism of drugs. Finally, a potential detection bias related to gastrointestinal symptoms more commonly seen in patients with diabetes and with multiple comorbidities should be pointed out. Taking into account the inconsistent findings and the potential confounders and detection bias in previous epidemiological studies, it is expected that there are still more to be explored for the clarification of the association between diabetes and gastric cancer.

Diabetes mellitus increases the risk of gastric cancer: A meta-analysis

AIM: To systematically assess the association between diabetes mellitus and the risk of gastric cancer.

METHODS: We searched Medline (PubMed), EMBASE, the Cochrane Library and CBN databases from January 1990 to July 2013. We also searched the references of qualifying articles. Cohort studies comparing the risk of gastric cancer between diabetic patients and control subjects were included. Fifteen studies met our criteria, and the quality of these studies was assessed using the Newcastle-Ottawa Quality Assessment Scale. Meta-analysis was performed using the random-effects model (DerSimonian-Laird method).

RESULTS: The meta-analysis showed an increased gastric cancer risk in diabetic patients [relative risk (RR) = 1.15, 95%CI: 1.11-1.19].

CONCLUSION: Diabetes mellitus may increase the risk of gastric cancer.

Diabetes mellitus carries a risk of gastric cancer: A meta-analysis

AIM: To investigate the association and quantify the relationship between diabetes mellitus (DM) and gastric cancer (GC) by an updated meta-analysis.

METHODS: The initial PubMed search identified 1233 publications. Studies not reporting GC or those not reporting actual number of GC were excluded. Twelve pertinent studies were retrieved from the PubMed database or from a manual search and considered for the meta-analysis. Pooled risk ratios and 95%CI were estimated by a random-effects model. Subgroup analysis was performed according to gender or geographical regions. Heterogeneity and publication bias were evaluated by I² and funnel plot analysis, respectively.

RESULTS: DM was significantly associated with GC with a RR of 1.41 (P = 0.006) (95%CI: 1.10-1.81). Subgroup analyses revealed that both sexes showed a significant association with GC, with a greater magnitude of risk in females (RR = 1.90; 95%CI: 1.27-2.85; P = 0.002) than in males (RR = 1.24; 95%CI: 1.08-1.43; P = 0.002). In addition, the link between DM and GC was significant in East Asian DM patients (RR = 1.77; 95%CI: 1.38-2.26; P < 0.00001) but not in Western DM patients (RR = 1.23; 95%CI: 0.90-1.68; P = 0.2). There was no evidence of publication bias, but the results indicated significant heterogeneity.

CONCLUSION: This updated meta-analysis has provided evidence of positive DM-GC associations. The limited information on potentially important clinical confounding factors in each study deserves further investigation.

Diabetes, insulin use, and gastric cancer: a population-based analysis of the Taiwanese

BACKGROUND

The association between diabetes and gastric cancer is rarely studied, and the risk associated with insulin use is not known.

MATERIALS AND METHODS

Gastric cancer prevalence rates in 2005 were calculated in 329,198 insurants aged 45 years or older and without type 1 diabetes from a random sample of 1,000,000 insurants of the National Health Insurance in Taiwan. Logistic regression evaluated whether diabetes or insulin use could be an independent risk factor after adjustment for age, sex, occupation, and living region. Sensitivity analyses were performed by excluding patients with diabetes duration <5 years and by excluding patients with cancers other than gastric cancer.

RESULTS

A total of 1464 cases of gastric cancer were identified. The prevalence of gastric cancer in diabetic and nondiabetic subjects were 595.0 and 387.7 per 100,000 population (P<0.0001), respectively. In diabetic patients, the respective prevalence of gastric cancer in insulin users and nonusers were 656.0 and 589.5 (P=0.4743). Adjusted odds ratio for diabetic versus nondiabetic subjects was 1.139 (1.022 to 1.270), and for insulin users versus nonusers in the diabetic patients was 1.002 (0.745 to 1.346). Age and male sex were also associated with significantly higher risk of gastric cancer, but the association with occupation and living region were not consistent. Results from sensitivity analyses were similar.

CONCLUSIONS

Diabetic patients may have a 14% higher risk of gastric cancer. However, insulin use is not related to the increased risk.

Metformin use and improved response to therapy in esophageal adenocarcinoma

BACKGROUND

We investigated the radiographic and pathologic response rate of esophageal adenocarcinoma treated with neoadjuvant chemoradiation in patients taking metformin.

MATERIAL AND METHODS

Two hundred eighty-five patients with esophageal adenocarcinoma treated with concurrent chemoradiation (CRT) followed by esophagectomy from 1997 to 2012 were included in the study, including 29 diabetics taking metformin, 21 diabetics not taking metformin and 235 non-diabetics. Pre- and post-treatment positron emission tomography (PET) scans were available for 204 patients. Pathologic response was graded at the time of surgery. Response rates were compared using both the χ(2) statistic as well as ANOVA with post-hoc LSD analysis. Multivariate logistic regression analysis was performed to control for predictors of pathologic complete response (CR) after CRT.

RESULTS

The overall rate of pathologic CR for the study population was 20%. The pathologic CR rate was higher in patients taking metformin (34.5%), compared to diabetic patients not taking metformin (4.8%, p = 0.01) and non-diabetic patients (19.6%, p = 0.05). Pathologic CR was related to metformin dose, with ≥ 1500 mg/d associated with a higher CR rate. No significant difference seen in pre-CRT maximum tumor SUV (p = 0.93), however post-CRT maximum SUV was significantly decreased in patients taking metformin (p = 0.05). On multivariate logistic regression, metformin use was independently associated with pathologic CR (p = 0.04). Metformin use was also associated with decreased in field loco-regional failure following radiation (p = 0.05).

CONCLUSION

Metformin use is associated with a dose-dependent increased response to CRT in esophageal cancer and may be a sensitizer to this therapy.

Pre-existing diabetes mellitus increases the risk of gastric cancer: A meta-analysis

AIM: To systematically assess the association between diabetes and incidence of gastric cancer.

METHODS: We searched MedLine (PubMed), EMBASE, and the Cochrane Library without any limitations with respect to publication date or language, we also searched the references of qualifying articles. Case-control studies and cohort studies comparing the risk of gastric cancer between diabetic patients and control subjects were included. We excluded studies reporting only standardized incidence ratios without control groups and those that investigated only mortality but not incidence. Seventeen studies met our criteria, and the qualities of these studies were assessed using the Newcastle-Ottawa Quality Assessment Scale. We performed a meta-analysis of pre-existing diabetes and gastric cancer incidence using the DerSimonian-Laird method for random-effects. For subgroup analyses, we separated the studies by study type, region, sex and method to determine confounding factors and reliability. We also conducted subgroup analyses to examine the effects of smoking, Helicobacter pylori (H. pylori) infection, and cancer site. Publication bias was evaluated using Begg’s test.

RESULTS: A random-effects model meta-analysis showed an increased gastric cancer risk in diabetic patients [relative risk (RR) = 1.19; 95%CI: 1.08-1.31]. Subgroup analyses indicated that this result persisted in cohort studies (RR = 1.20; 95%CI: 1.08-1.34), in studies on populations of both Western (RR = 1.18; 95%CI: 1.03-1.36) and Eastern countries (RR = 1.19; 95%CI: 1.02-1.38), in a female subgroup (RR=1.24; 95%CI: 1.01-1.52), and in highly qualified studies (RR = 1.17; 95%CI: 1.05-1.31). Moreover, these results persisted when the analysis was confined to studies adjusted for well-known gastric cancer risk factors such as smoking (RR = 1.17; 95%CI: 1.01-1.34) and H. pylori infection (RR = 2.35; 95%CI: 1.24-4.46).

CONCLUSION: Pre-existing diabetes mellitus may increase the risk of gastric cancer by approximately 19%. This effect seems to be unrelated to geographical region.

Diabetes and risk of esophageal and gastric adenocarcinomas

Diabetes has been consistently associated with an increased risk of liver, pancreas and endometrial cancer and has been implicated as a risk factor for esophageal and gastric cancers, although this association has been less well studied. We sought to determine the role of diabetes in the etiology of esophageal, gastric cardia and distal gastric adenocarcinomas (DGAs). This analysis included patients with esophageal adenocarcinoma (EA) (n = 209), gastric cardia adenocarcinoma (GCA) (n = 257) and DGA (n = 382), and 1,309 control participants from a population-based case-control study conducted in Los Angeles County. The study included non-Hispanic whites, African Americans, Hispanics and Asian Americans. The association of diabetes with the three tumor types was estimated using polytomous logistic regression. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated. Nine percent of control participants and 13% of the case patients reported a history of diabetes. After adjustment for age, gender, race, birthplace, education, cigarette smoking status and body mass index, diabetes was associated with an increased risk of EA (OR, 1.48; 95% CI, 0.94-2.32; p = 0.089) and DGA (OR, 1.47; 95% CI, 1.01-2.15; p = 0.045), but was not associated with risk of GCA (OR, 0.96; 95% CI, 0.59-1.55; p = 0.87). However, the association between diabetes and risk of DGA was statistically significant only among patients for whom we interviewed their next of kin. Our study further investigated the association between diabetes and adenocarcinomas of the esophagus and distal stomach.

Diabetes mellitus and gastric carcinoma: Is there an association?

Diabetes mellitus (DM) has been associated with the risk of several gastrointestinal cancers including liver, pancreas, colon and rectum. However, the evidence is inconclusive for gastric adenocarcinoma (GC). In the current review, we summarize 20 population-based cohort studies that compared GC incidence and mortality between diabetic and non-diabetic population. We discuss the shared risk factors and provide qualitative and quantitative (meta-analytic) summary of the current evidence evaluating the association by high-risk subgroups. The overall risk-estimate based on all studies did not show an increased risk of GC in diabetics. However, 2 cohort studies conducted in East Asian countries, where Helicobacter pylori infection and GC rates are higher, showed a higher risk of GC in diabetics. Additionally, high plasma glucose levels in the presence of Helicobacter pylori infection increased the risk of GC by over four times, suggesting a multiplicative effect. Results from the meta-analysis show that, the risk of GC was also higher in populations with greater prevalence of type 1 DM (relative risk = 1.60), suggesting an insulin-independent carcinogenic process in this subgroup. The risk of mortality due to GC was higher in diabetics compared to non-diabetics (relative risk = 1.62). Although the overall risk estimates do not show an association between DM and GC, complex interactions between infectious, molecular, demographic and host factors may convey a higher risk in certain subgroups. Future studies should be sufficiently powered for detailed subgroup analysis to elucidate the causative and mechanistic association between DM and GC.

Diabetes mellitus and risk of gastric cancer: a systematic review and meta-analysis of observational studies

AIM

Increasing evidence suggests that a history of diabetes may be involved in the development of various sites of cancer. However, the association of diabetes and risk of gastric cancer (GC) remains unclear.

METHODS

We identified studies by a literature search of MEDLINE (from 1 January 1966), Web of Science (from 1 January 1994), and EMBASE (from 1 January 1974 through 31 May 2011), and by searching the reference lists of pertinent articles. All data were extracted independently by two investigators using a standardized data abstraction tool. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were calculated with a random-effects model. Between-study heterogeneity was assessed using the Cochran's Q and I statistics.

RESULTS

A total of 21 studies (four case-control studies, 17 cohort studies) were included in this meta-analysis. Analysis of these 21 studies found that compared with nondiabetic individuals, diabetic individuals had a similar risk of GC (SRRs, 1.09; 95% CI: 0.98-1.22). There was strong evidence of heterogeneity among these studies (P<0.001, I²=81.2%). A subgrouped analysis found that diabetic women had 18% increased risk of GC (SRRs, 1.18; 95% CI: 1.01-1.39), whereas it was not the case with diabetic men. No significant public bias was found in this study.

CONCLUSION

These findings of this systematic review indicate that compared with nondiabetic individuals, diabetic women have an 18% increased risk of GC development. However, diabetic men have a similar risk of GC.

Gastrointestinal signs and symptoms among persons with diabetes mellitus

AIM

To determine the prevalence of gastrointestinal symptoms and signs among persons with diabetes mellitus in a specialist hospital.

BACKGROUND

Gastrointestinal symptoms and signs are common among patients with diabetes mellitus. Morbidity from.

PATIENTS AND METHODS

In this descriptive, cross-sectional study, subjects from the general population with diabetes (n=200) were recruited for this study. Subjects were randomly chosen from patients known to have diabetes, (type I&II), attending the diabetes clinic at Sina University Hospital, in Tabriz during 2003. The questionnaire recorded gastrointestinal symptoms among the subject population.

RESULTS

91% and 9% of patients had Type II and I diabetes, respectively. Sixty seven percent of them had poor controlled diabetes and only 3% had well controlled diabetes. Gastrointestinal symptoms and signs were reported in 92% of patients. The common GI symptoms were constipation (59.5%), followed by bloating (44%), abdominal pain (31%), dyspepsia (30%), and mass protruding through anus (22.5%). Abdominal tenderness on deep palpation was the commonest clinical sign (54%). GI symptoms were more prevalent in subjects aged 60-69 years (97.2%). Seventy four percent of patients with GI signs and symptoms had complications such as neuropathy 61.5% and retinopathy associated with neuropathy 38.5%.

CONCLUSION

The prevalence of GI symptoms and signs in the population studies was higher than that reported from other populations, and there is a relationship between glycaemic control and complications of diabetes in diabetic subjects.