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

Metabolic risk factors of colorectal cancer: Umbrella review

BACKGROUND AND AIM

The association between metabolic factors and colorectal cancer (CRC) risk is inconclusive. This umbrella review aimed to summarise and describe the association using existing systematic reviews and/or meta-analyses.

METHOD

Four databases (Medline, Scopus, Web of Science, and Cochrane Library) were searched for systematic reviews and/or meta-analyses of observational studies. Two independent authors extracted data on the summary estimated effect and heterogeneity of studies using I2 from the individual reviews. The Assessing the Methodological Quality of Systematic Reviews (AMSTAR 2) tool was used to evaluate the methodological quality.

RESULTS

49 articles were included in this review. Although most included studies were graded with critically low methodological quality (81.6 %), we found a significant positive association between obesity (summary relative risk (SRR) range 1.19-1.49), diabetes mellitus (SRR range 1.20-1.37), hypertension (SRR range 1.07-1.62), metabolic syndrome (SRR range 1.25-1.36), non-alcoholic fatty liver disease (pooled odds ratio (POR) range 1.13-1.56), and risk of CRC. Higher serum high-density lipoprotein cholesterol levels were associated with a lower risk of CRC in 3/6 reviews, while others did not find any association. There was no clear association between high triglyceride levels, total cholesterol levels, low-density lipoprotein cholesterol levels, and risk of CRC.

CONCLUSION

This umbrella review identified that most metabolic factors are significantly associated with increased risk of CRC. Thus, people affected by metabolic factors may be benefited from CRC screening and surveillance.

Glycemic Burden and Clinical Outcomes of Early Stage Hepatocellular Carcinoma after Curative Treatment

Early-stage hepatocellular carcinoma (HCC) is still difficult to cure for its high recurrence rate. This study aimed to examine whether glycemic burden management could be one way to improve outcomes of early-stage HCC. A total of 137 very early or early-stage HCC patients who underwent resection or ablation at Samsung Medical Center and had glycemic burden assessment were analyzed. Glycemic burden was assessed using hemoglobin A1c (HbA1c) level. Outcomes were recurrence and overall survival. Risks of recurrence and overall survival were compared according to glycemic burden using a cut-off point of 6.5% or two cut-off points of 6.0% and 7.5%. Overall, 51 (37.2%) patients experienced HCC recurrence. The adjusted hazard ratio (aHR) for recurrence comparing patients with HbA1c > 6.5% to those with HbA1c ≤ 6.5% was 2.66 (95% CI: 1.26-5.78). The risk of recurrence increased in a dose-dependent manner by glycemic burden; aHR for 6.0 < HbA1c ≤ 7.5%: 2.00 (95% CI: 0.78-5.55); aHR for HbA1c > 7.5%: 6.05 (95% CI: 2.31-17.5). Mortality was observed in 16 (11.7%) patients. The risk of mortality was higher for HbA1c > 6.5% than for HbA1c ≤ 6.5% (aHR: 2.33; 95% CI: 1.10-5.08). There was also a dose-response relationship between overall survival and glycemic burden. Glycemic burden assessed using HbA1c level was significantly associated with outcomes of early-stage HCC patients. Good glycemic control could be a therapeutic goal to improve clinical outcomes in these populations.

Could Insulin Be a Better Regulator of Appetite/Satiety Balance and Body Weight Maintenance in Response to Glucose Exposure Compared to Sucrose Substitutes? Unraveling Current Knowledge and Searching for More Appropriate Choices

BACKGROUND

Insulin exerts a crucial impact on glucose control, cellular growing, function, and metabolism. It is partially modulated by nutrients, especially as a response to the intake of foods, including carbohydrates. Moreover, insulin can exert an anorexigenic effect when inserted into the hypothalamus of the brain, in which a complex network of an appetite/hunger control system occurs. The current literature review aims at thoroughly summarizing and scrutinizing whether insulin release in response to glucose exposure may be a better choice to control body weight gain and related diseases compared to the use of sucrose substitutes (SSs) in combination with a long-term, well-balanced diet.

METHODS

This is a comprehensive literature review, which was performed through searching in-depth for the most accurate scientific databases and applying effective and relevant keywords.

RESULTS

The insulin action can be inserted into the hypothalamic orexigenic/anorexigenic complex system, activating several anorexigenic peptides, increasing the hedonic aspect of food intake, and effectively controlling the human body weight. In contrast, SSs appear not to affect the orexigenic/anorexigenic complex system, resulting in more cases of uncontrolled body weight maintenance while also increasing the risk of developing related diseases.

CONCLUSIONS

Most evidence, mainly derived from in vitro and in vivo animal studies, has reinforced the insulin anorexigenic action in the hypothalamus of the brain. Simultaneously, most available clinical studies showed that SSs during a well-balanced diet either maintain or even increase body weight, which may indirectly be ascribed to the fact that they cannot cover the hedonic aspect of food intake. However, there is a strong demand for long-term longitudinal surveys to effectively specify the impact of SSs on human metabolic health.

Association between glycemic status and the risk of gastric cancer in pre/peri-and postmenopausal women: A nationwide cohort study

PURPOSE

This study aimed to assess the correlation between glycemic status (prediabetes and type 2 diabetes mellitus) and the risk of gastric cancer according to menopausal status.

METHODS

A total of 982,559 pre/peri-menopausal and 1445,419 postmenopausal women aged ≥ 40, who underwent the Korean national health screening in 2009, were included and followed up until 2018. Hazard ratio (HR) and 95% confidence interval (CI) were calculated for development of gastric cancers according to hyperglycemic status in both groups using Cox proportional hazards models.

RESULTS

Over a mean follow-up period of 8.3 years, 3259 (0.33%) pre/peri-menopausal women and 13,245 (0.92%) postmenopausal women were diagnosed with gastric cancer. In postmenopausal women, only diabetes mellitus conferred a higher risk of gastric cancer compared to normal glycemic status (HR, 1.15; 95% CI, 1.09-1.20), with an increasing trend of gastric cancers from prediabetes to diabetes (P for trend < 0.001) observed regardless of menopausal status. Obesity, smoking, and heavy alcohol consumption was associated with increased gastric cancer risk mainly in the postmenopausal period.

CONCLUSIONS

The risk of gastric cancer escalates with deteriorating glycemic status in a dose-response manner. Diabetes mellitus is linked with an elevated risk of gastric cancer in postmenopausal women.

Associations between diabetes and cancer: A 10-year national population-based retrospective cohort study

AIMS

To investigate the risk of cancer in people with diabetes compared to the population without diabetes and to gain insight into the timely association between diabetes and cancer at national level.

METHODS

A retrospective cohort study was conducted to analyse the role of diabetes in the development of cancer, based on service utilisation and antidiabetic dispensing data of the population between 2010 and 2021. Univariate and multivariate Cox regression were used to examine how diabetes status, in relationship with age and sex are related to the time to cancer diagnosis.

RESULTS

Examining a population of 3 681 774 individuals, people with diabetes have a consistently higher risk for cancer diagnosis for each cancer site studied. Diabetes adds the highest risk for pancreatic cancer (HR = 2.294, 99 % CI: 2.099; 2.507) and for liver cancer (HR = 1.830, 99 % CI: 1.631; 2.054); it adds the lowest - but still significant - risk for breast cancer (HR = 1.137, 99 % CI: 1.055; 1.227) and prostate cancer (HR = 1.171, 99 % CI: 1.071; 1.280).The difference in cancer rate is driven by the younger age group (40-54 years: for patients with diabetes 5.4 % vs. controls 4.4 %; 70-89 years: for patients with diabetes 12.7 % vs. controls 12.4 %). There are no consistent results whether the presence of diabetes increases the risk of cancer diagnosis differently in males and females. The cancer incidence starts to increase before the diagnosis of diabetes and peaks in the year after. By the year after the start of the inclusion date, the incidence is 114/10,000 population in the control group, vs 195/10,000 population in the group with diabetes. Following this, the incidence drops close to the control group.

CONCLUSIONS

Screening activities should be revised and the guidelines on diabetes should be complemented with recommendations on cancer prevention also considering that the cancer incidence is highest around the time of the diagnosis of diabetes. For prostate cancer, our results contradict many previous studies, and further research is recommended to clarify this.

Correlation between High Incidence of Colorectal Neoplastic Polyps and High-risk Adenomas in Patients with Diabetes Mellitus: A Retrospective Study

BACKGROUND

Early detection and resection of colorectal polyps by routine colonoscopy screening can be effective in reducing the risk of colorectal cancer (CRC).

OBJECTIVE

This study aimed to determine the association between diabetes mellitus (DM) and different types of colorectal polyps in the Chinese population.

METHODS

A retrospective analysis was performed on inpatients admitted to the Gastroenterology Department of our hospital from January to December 2019. Clinical data, and colonoscopy and pathology findings of the subjects were collected. Bivariate analysis was used to assess factors associated with colorectal polyps. Significant variables from the bivariate evaluation were included in a stepwise multivariate logistic regression analysis to recognize independent predictors of neoplastic polyps and high-risk adenomas.

RESULTS

The proportion of patients with DM was significantly higher in patients with neoplastic polyps and high-risk adenomas than in patients without polyps. Age ≥ 50 years, male gender, and a first-degree relative with a history of CRC were independent risk factors for neoplastic polyps and high-risk adenomas, even in non-smokers. An independent risk factor analysis that did not include a family history of CRC showed that age, gender, and alcohol consumption were independent risk factors for neoplastic polyps and high-risk adenomas. DM was an independent risk factor for high-risk adenomas (OR = 2.902, 95% CI = 1.221-6.899; p = 0.016) after adjusting for age, gender, alcohol consumption, and body mass index. Thus, a history of DM significantly increases the risk of high-risk adenomas.

CONCLUSION

This study demonstrated that patients with DM, age ≥ 50 years, male gender, alcohol consumption, and a first-degree relative with a history of CRC should undergo regular endoscopic screening and colonic polypectomy.

Systemic Diseases and Gastrointestinal Cancer Risk

Importance

Gastrointestinal (GI) cancers are the second leading cause of cancer-related deaths worldwide.

Observations

The global challenges GI cancers pose are high, especially in middle- and low-income countries. Patients with these cancers present with symptoms of poor appetite, weight loss, heartburn, abdominal pain, fatigue and anaemia. Several risk factors contribute to GI cancers, including age, gender, obesity, pathogenic infections, smoking cigarettes, alcohol consumption and dietary habits. Most of these cancers are sporadic. However, some patients are at high risk due to a family history of GI cancers. Systemic diseases affect multiple organs, and their chronic occurrence elicits inflammatory responses at various sites. These diseases also contribute to GI cancers.

Conclusion and Relevance

In this review, we discuss that untreated systemic diseases, including diabetes, hepatitis, acquired immune deficiency syndrome, ulcers and hypertension, can potentially lead to GI cancers if they remain untreated for a longer period. Systemic diseases initiate oxidative stress, inflammatory pathways and genetic manipulations, which altogether confer risks to GI cancers. Here, we describe the association between systemic diseases and their underlying mechanisms leading to GI cancers.

Obesity, diabetes mellitus, and pancreatic carcinogenesis: Correlations, prevention, and diagnostic implications

The prevalence of obesity, diabetes mellitus (DM), and pancreatic cancer (PC) has been consistently increasing in the last two decades worldwide. Sharing various influential risk factors in genetics and environmental inducers in pathogenesis, the close correlations of these three diseases have been demonstrated in plenty of clinical studies using multiple parameters among different populations. On the contrary, most measures aimed to manage and treat obesity and DM effectively reduce the risk and prevent PC occurrence, yet certain drugs can inversely promote pancreatic carcinogenesis instead. Most importantly, an elevation of blood glucose with or without a reduction in body weight, along with other potential tools, may provide valuable clues for detecting PC at an early stage in patients with obesity and DM, favoring a timely intervention and prolonging survival. Herein, the epidemiological and etiological correlations among these three diseases and the supporting clinical evidence of their connections are first summarized to favor a better and more thorough understanding of obesity- and DM-related pancreatic carcinogenesis. After comparing the distinct impacts of different weight-lowering and anti-diabetic treatments on the risk of PC, the possible diagnostic implications of hyperglycemia and weight loss in PC screening are also addressed in detail.

Association between diabetes and cancer. Current mechanistic insights into the association and future challenges

Compelling pieces of epidemiological, clinical, and experimental research have demonstrated that Diabetes mellitus (DM) is a major risk factor associated with increased cancer incidence and mortality in many human neoplasms. In the pathophysiology context of DM, many of the main classical actors are relevant elements that can fuel the different steps of the carcinogenesis process. Hyperglycemia, hyperinsulinemia, metabolic inflammation, and dyslipidemia are among the classic contributors to this association. Furthermore, new emerging actors have received particular attention in the last few years, and compelling data support that the microbiome, the epigenetic changes, the reticulum endoplasmic stress, and the increased glycolytic influx also play important roles in promoting the development of many cancer types. The arsenal of glucose-lowering therapeutic agents used for treating diabetes is wide and diverse, and a growing body of data raised during the last two decades has tried to clarify the contribution of therapeutic agents to this association. However, this research area remains controversial, because some anti-diabetic drugs are now considered as either promotors or protecting elements. In the present review, we intend to highlight the compelling epidemiological shreds of evidence that support this association, as well as the mechanistic contributions of many of these potential pathological mechanisms, some controversial points as well as future challenges.

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.

Rectal Cancer and Diabetes Relationship: An Evidence-Based Overview for Healthcare Providers

As the third most frequently diagnosed cancer through the worldwide, colorectal cancer (CRC) is the fourth leading cause and account for around 8% of all cancer-related death. Diabetes mellitus (DM) is a complex metabolic disorder characterized by chronic hyperglycemia and inflammation due to deficiency in insulin secretion or dysregulation of the insulin action pathway, which further leads to dysfunction and failure of multiple organs. Many advances have been made in the diagnosis and management of rectal cancer. Although colorectal cancer survival is severely dependent on the stage of disease at diagnosis, it might also be influenced by several risk factors. The relationship between colorectal cancer and diabetes is a complex one and can raise problems in both diagnosis and the management of patients with both conditions. Metabolic pathways of the type II diabetes, glucose intolerance and obesity can be considered as a link to rectal cancer. This article provides not just an overview of the epidemiology, diagnosis and management of CRC and DM, but also highlights of CRC and DM relationship.

Reduced serum high-density lipoprotein cholesterol levels and aberrantly expressed cholesterol metabolism genes in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a common malignant tumor of the gastrointestinal tract. Lipid metabolism, as an important part of material and energy circulation, is well known to play a crucial role in CRC.

AIM

To explore the relationship between serum lipids and CRC development and identify aberrantly expressed cholesterol metabolism genes in CRC.

METHODS

We retrospectively collected 843 patients who had confirmed CRC and received surgical resection from 2013 to 2015 at the Cancer Hospital of the Chinese Academy of Medical Sciences as our research subjects. The levels of serum total cholesterol (TC), triglycerides, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), LDL-C/HDL-C and clinical features were collected and statistically analyzed by SPSS. Then, we used the data from Oncomine to screen the differentially expressed genes (DEGs) of the cholesterol metabolism pathway in CRC and used Gene Expression Profiling Interactive Analysis to confirm the candidate DEGs. PrognoScan was used to analyze the prognostic value of the DEGs, and Search Tool for the Retrieval of Interacting Genes was used to construct the protein–protein interaction network of DEGs.

RESULTS

The serum HDL-C level in CRC patients was significantly correlated with tumor size, and patients whose tumor size was more than 5 cm had a lower serum HDL-C level (1.18 ± 0.41 mmol/L vs 1.25 ± 0.35 mmol/L, P < 0.01) than their counterparts. In addition, TC/HDL (4.19 ± 1.33 vs 3.93 ± 1.26, P < 0.01) and LDL-C/HDL-C (2.83 ± 1.10 vs 2.61 ± 0.96, P < 0.01) were higher in patients with larger tumors. The levels of HDL-C (P < 0.05), TC/HDL-C (P < 0.01) and LDL-C/HDL-C (P < 0.05) varied in different stages of CRC patients, and the differences were significant. We screened 14 differentially expressed genes (DEGs) of the cholesterol metabolism pathway in CRC and confirmed that lipoprotein receptor-related protein 8 (LRP8), PCSK9, low-density lipoprotein receptor (LDLR), MBTPS2 and FDXR are upregulated, while ABCA1 and OSBPL1A are downregulated in cancer tissue. Higher expression of LDLR (HR = 3.12, 95%CI: 1.77-5.49, P < 0.001), ABCA1 (HR = 1.66, 95%CI: 1.11-2.48, P = 0.012) and OSBPL1A (HR = 1.38, 95%CI: 1.01-1.89, P = 0.041) all yielded significantly poorer DFS outcomes. Higher expression of FDXR (HR = 0.7, 95%CI: 0.47-1.05, P = 0.002) was correlated with longer DFS. LDLR, ABCA1, OSBPL1A and FDXR were involved in many important cellular function pathways.

CONCLUSION

Serum HDL-C levels are associated with tumor size and stage in CRC patients. LRP8, PCSK9, LDLR, MBTPS2 and FDXR are upregulated, while ABCA1 and OSBPL1A are downregulated in CRC. Among them, LDLR, ABCA1, OSBPL1A and FDXR were valuable prognostic factors of DFS and were involved in important cellular function pathways.

Relationship between diabetes and risk of gastric cancer: A systematic review and meta-analysis of cohort studies

Patients with diabetes mellitus (DM) are at increased risk of developing several cancers; however, there is a lack of consensus on the relationship between gastric cancer (GC) and DM. This study aimed to explore the association between GC and DM based on the type and duration of DM. We searched nine databases from inception to December 1, 2021, and 40 cohort studies that evaluated the relationship between DM and the incidence of GC were included in this review. The summary relative ratios for the relationship of GC incidence with type 1 DM (T1DM) and type 2 DM (T2DM) were estimated using the fixed-effect and random-effect models, respectively. The risk of GC was 46% and 14% higher in individuals with T1DM and T2DM, respectively, than in those without diabetes. The risk of GC development in patients with diabetes showed a U-shape curve of change with DM duration. Our meta-analysis suggested that both T1DM and T2DM present a higher risk of GC development. The risk of GC may be influenced by the different time windows following the onset of diabetes. Future studies are required to explore the mechanism by which the duration of DM, antidiabetic medication use, and sex affect this association.

High HbA1c is a risk factor for complications after hepatectomy and influences for hepatocellular carcinoma without HBV and HCV infection

Background

Currently, the population with type 2 diabetes mellitus (DM) is increasing worldwide. However, the influence of DM or hyperglycemia on the outcome of resected hepatocellular carcinoma (HCC) is unclear.

Methods

We analyzed 756 patients with HCC who underwent hepatectomy. These patients were assigned to an HbA1c ≥7.0% (H-A1c; n=100) or HbA1c <7.0% (L-A1c; n=656) group depending on their HbA1c level at admission. We investigated prognoses, clinicopathological characteristics and surgical outcomes including morbidities of HCC patients with high HbA1c, prognoses according to the treatment for DM were also investigated.

Results

Among all patients and those with hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, overall survival (OS) and relapse-free survival (RFS) did not differ significantly between the H-A1c and L-A1c groups. In contrast, the 5-year OS rate of the H-A1c group was 55% and that of the L-A1c group 71% among patients without HBV and HCV (NBNC patients) (P=0.03). Among NBNC patients, the median RFS of the H-A1c group was 13 months, and that of the L-A1c group was 26 months (P=0.02). In addition, metformin use was an independent favorable factor for both OS and RFS. The H-A1c group had significantly higher rates of hyperbilirubinemia, wound infection, and pneumonia.

Conclusions

HCC patients with high HbA1c might have poor prognoses for both survival and recurrence in NBNC-HCC. High HbA1c may also be a risk factor for morbidities after hepatectomy. Metformin use may constitute a good option for NBNC patients with HCC.

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.

Timing of surgery for asymptomatic patients with severe aortic valve stenosis: An updated systematic review and meta-analysis

BACKGROUND

The research findings concerning the effect of early surgery on mortality among asymptomatic patients with severe aortic valve stenosis (AS) are controversial and contradictory. In this study, the total weight of evidence regarding early surgery versus conservative management in these population was examined.

METHODS

Embase, PubMed, CENTRAL, and CINAHL databases were thoroughly searched without language restriction until 29 February, 2020. We included all studies exploring the mortality in asymptomatic patients with severe AS comparing early surgery with conservative management and obtained data in a standard form. Pooled relative risks ratios (RRs) and 95% confidence intervals (CI) were pooled by using a random- or fixed-effects model and by using intention-to-treat principle. Randomized controlled trials (RCTs) and observational studies (OSs) were analyzed separately.

RESULTS

Finally, 8 studies involving 2462 patients were enrolled, including 1 RCT and 7 OSs. In the OSs, early surgery was linked with significant reduction among all-cause mortality (RR & 95% CI, I²: 0.32 (0.18-0.57), 84.9%) and cardiac death (0.28 (0.18-0.45), 62.5%) in asymptomatic patients with severe AS. The superiority of early surgery over conservative management in reducing all-cause mortality in these patients is also intensified in the RCT.

CONCLUSIONS

The existing RCT and OSs indicate that earlier surgery is associated with better outcomes for asymptomatic patients with severe AS. Nevertheless, more well-designed and large-sized RCTs are needed to find an individual approach focusing on individual risk stratification and staging.

Sex-specific association between type 1 diabetes and the risk of end-stage renal disease: a systematic review and meta-analysis

PURPOSE

This meta-analysis was conducted given the inconsistent findings of studies regarding the sex discrepancy in the relationship between type 1 diabetes (T1D) and the risk of end-stage renal disease (ESRD).

METHODS

Articles published on PubMed between January 1, 1966 and March 31, 2019 were systematically retrieved without language restrictions. The included articles all presented sex-specific data of the incidence rate ratio, standardized incidence or mortality ratio, hazard ratio, relative risk, or odds ratio, or provided data to estimate the association between T1D and ESRD or kidney disease-related mortality. The gender-specific effect estimates and pooled ratio (female-to-male) for ESRD and for deaths from T1D-related renal disease were acquired via a random-effects meta-analysis with inverse variance weighting, regardless of heterogeneity evaluated based on the I² statistic.

RESULTS

Nineteen studies, including 122,842 individuals, were finally selected for this meta-analysis. Sex differences in effect estimates were found in ESRD (pooled ratio = 0.81 (95% confidence interval 0.69-0.94)) with considerable heterogeneity (I² = 66.9%), but not in mortality with T1D-associated renal disease.

CONCLUSION

Women with T1D have a lower risk of ESRD compared with that in men, but this finding may be biased by potential confounding factors and must be verified by other well-planned prospective studies.

The association between gestational diabetes mellitus and cancer in women: A systematic review and meta-analysis of observational studies

AIM

Both type 1 and type 2 diabetes are associated with greater risk of a variety of cancers. However, the association between gestational diabetes mellitus (GDM) and risk of cancer has so far not been well addressed. This study aimed to summarize the epidemiological evidence of the association between GDM and subsequent risk of cancer.

METHODS

PubMed and Embase databases were searched for relevant studies, and a random-effects model was used to calculate the summary relative risks (RRs) along with the corresponding 95% confidence intervals (CIs).

RESULTS

A total of 17 observational studies were selected, comprising 7 case-control and 10 cohort studies. Pooled effect estimates retrieved from these 17 studies showed that GDM was associated with an increased risk of breast cancer in Asia (pooled RR: 1.31, 95% CI: 1.01-1.70), but not in other regions, and also with thyroid cancer (RR: 1.28, 95% CI: 1.16-1.42), stomach cancer (RR: 1.43, 95% CI: 1.02-2.00) and liver cancer (RR: 1.27, 95% CI: 1.03-1.55). However, GDM was not associated with any increased risk of colon (RR: 1.41, 95% CI: 0.90-2.21), colorectal (RR: 1.16, 95% CI: 0.95-1.41), ovarian (RR: 1.14, 95% CI: 0.90-1.44), cervical (RR: 1.02, 95% CI: 0.81-1.29), pancreatic (RR: 3.49, 95% CI: 0.80-15.23), brain and nervous system (RR: 1.26, 95% CI: 0.80-1.97), blood (leukaemia, RR: 0.77, 95% CI: 0.45-1.30), endometrial (RR: 0.77, 95% CI: 0.20-2.98), skin (RR: 1.13, 95% CI: 0.81-1.59) or urological (RR: 0.98, 95% CI: 0.73-1.31) cancers.

CONCLUSION

GDM is associated with a greater risk of cancer in women, including breast, thyroid, stomach and liver cancers. However, further investigation is nonetheless warranted.

Middle-aged men with type 2 diabetes as potential candidates for pancreatic cancer screening: a 10-year nationwide population-based cohort study

AIMS

Before developing a national screening program for pancreatic cancer, more detailed and reliable estimation of pancreatic cancer incidence rate is needed according to sex, age, and diabetes mellitus status.

METHODS

Among populations who underwent a biennial or annual evaluation provided by the National Health Insurance Service Database of Claims between 2006 and 2015, data were evaluated from the medical records of 34.2 million individuals aged 30 years and over.

RESULTS

The annual incidence rate (IR; per 100,000) of pancreatic cancer in 2006 was 5.96, and the IR in 2015 increased to 8.92. The IRs increased consistently and significantly with age (p for trend < 0.0001). The incidence rate ratio (IRR; after adjusting for age and sex) of pancreatic cancer was higher (about 1.5 times) in males than in females for all ages. In particular, the IR (15.8) of pancreatic cancer between 50 and 59 years in patients with diabetes was strikingly higher compared to that in patients without diabetes (IR 7.6). Furthermore, the pancreatic cancer IR (19.1) of men with diabetes between 50 and 59 years was similar to the IR (20.2) in women with diabetes between 60 and 69 years, and it was even greater than the IR (17.0) in non-diabetic women between 60 and 69 years.

CONCLUSIONS

In middle-aged populations, men with type 2 diabetes had the highest relative risk. Their annual incidence rate of pancreatic cancer persistently increased and was higher by about 10-30% than in women with diabetes.

Cancer has overtaken cardiovascular disease as the commonest cause of death in Scottish type 2 diabetes patients: A population-based study (The Ayrshire Diabetes Follow-up Cohort study)

AIMS/INTRODUCTION

The increased mortality risk associated with diabetes is well established. The aim of the present study was to determine the causes of death of people with type 2 diabetes in Ayrshire and Arran, Scotland, between 2009 and 2014, and compare them with the national mortality rates.

MATERIALS AND METHODS

The primary causes of death were collated. The causes of death were clustered into nine categories: heart disease, stroke, infection, renal failure, respiratory disorders, cancer, mental health, decompensated diabetes and other. The total rates were compared with national rates using the standardized mortality ratio (SMR), and then individually with heart disease, cerebrovascular disease and cancer.

RESULTS

There were 2116 deaths with the SMR, and 145 of those were caused by type 2 diabetes (n = 16,643; 95% confidence interval 139-152; P < 0.01). The SMR was >100 in all age bands, particularly in the younger age bands (P < 0.01). The SMR was consistently higher for women (P < 0.01). The SMR for heart disease was significantly >100 for both sexes in all age bands <65 years (P < 0.05). There was no difference in mortality causes related to the duration of diabetes. The most common cause of death was cancer (27.8%), followed by heart disease (24.1%). The SMR for cancer deaths was significantly elevated in women (120, 95% CI 104-137; P < 0.05).

CONCLUSIONS

This study confirmed increased mortality risk in type 2 diabetes patients, and suggests that where cardiovascular risk factors are being treated aggressively, cancer takes on a greater importance in the cause of death. Should greater consideration now be given for cancer as a complication of diabetes?

Increased Risk of Site-Specific Cancer in People with Type 2 Diabetes: A National Cohort Study

A retrospective cohort design was used with the objective to evaluate cancer risk among people with type 2 diabetes mellitus (T2DM) in Lithuania. The cohort was established by identifying all patients with the first diagnosis of T2DM in the National Health Insurance Fund database during 2000-2012. Cancer cases were identified by record linkage with the Lithuanian Cancer Registry. Standardized incidence ratios (SIRs) were calculated. Of the 127,290 people that were included, 5959 cases of cancer in men and 6661 cancer cases in women with T2DM were observed. A statistically significant increase in risk for all cancer sites was observed in women, SIR 1.16 (95% CI 1.14-1.19), but not in men, SIR 1.00 (95% CI 0.98-1.03). Among males, a significant increase of liver (SIR 2.11, 95% CI 1.79-2.49]), pancreas (SIR 1.77, 95% CI 1.57-1.99), kidney (SIR 1.46 95% CI 1.31-1.62), thyroid (SIR 1.83, 95% CI 1.32-2.54), colorectal (SIR 1.23, 95% CI 1.14-1.31]), skin melanoma (SIR 1.40, 95% CI 1.11-1.76), and non-melanoma skin (SIR 1.14, 95% CI 1.05-1.23) cancer was observed. For females with T2DM, a significant increase in risk of cancer of the liver (SIR 1.45, 95% CI 1.17-1.79), pancreas (SIR 1.74, 95% CI 1.56-1.93), kidney (SIR = 1.43, 95% CI 1.28-1.60), thyroid (SIR = 1.40, 95% CI 1.22-1.62), breast (SIR = 1.24, 95% CI 1.17-1.31), and corpus uteri (SIR 2.07, 95% CI 1.93-2.21) was observed. In conclusion, people with T2DM in Lithuania had an increased risk of site-specific cancer.

Exploring the link between diabetes and pancreatic cancer

Introduction: Epidemiological studies indicate an association between type 2 diabetes and pancreatic cancer but the complex and multidirectional relationship between them remains unclear. Areas covered: We summarized epidemiological evidence on diabetes and pancreatic cancer exploring the time-risk relationship. We described mechanisms linking long-standing diabetes to pancreatic cancer. We discussed pancreatic cancer-associated diabetes and its implication in the early detection of pancreatic cancer. Expert opinion: The markedly increased risk of pancreatic cancer in patients with new-onset diabetes compared with long-standing diabetes observed in several epidemiological studies indicates a complex and bidirectional connection, with long-standing diabetes being a predisposing factor for pancreatic cancer (increasing the risk of the malignancy 1.5- to 2-fold) and new-onset diabetes an early manifestation of the tumor. Identifying clinical features and biomarkers to distinguish pancreatic cancer-associated diabetes from type 2 diabetes is an important goal to improve management and survival of this cancer. Imaging (MRI) for middle-age patients with new-onset diabetes may be considered.

Sex differences in the association between diabetes and risk of cardiovascular disease, cancer, and all-cause and cause-specific mortality: a systematic review and meta-analysis of 5,162,654 participants

BACKGROUND

Studies have suggested sex differences in the mortality rate associated with diabetes. We conducted a meta-analysis to estimate the relative effect of diabetes on the risk of all-cause, cancer, cardiovascular disease (CVD), infectious disease, and respiratory disease mortality in women compared with men.

METHODS

Studies published from their inception to April 1, 2018, identified through a systematic search of PubMed and EMBASE and review of references. We used the sex-specific RRs to derive the women-to-men ratio of RRs (RRR) and 95% CIs from each study. Subsequently, the RRR for each outcome was pooled with random-effects meta-analysis weighted by the inverse of the variances of the log RRRs.

RESULTS

Forty-nine studies with 86 prospective cohorts met the inclusion criteria and were eligible for analysis. The pooled women-to-men RRR showed a 13% greater risk of all-cause mortality associated with diabetes in women than in men (RRR 1.13, 95% CI 1.07 to 1.19; P < 0.001). The pooled multiple-adjusted RRR indicated a 30% significantly greater excess risk of CVD mortality in women with diabetes compared with men (RRR 1.30, 95% CI 1.13 to 1.49; P < 0.001). Compared with men with diabetes, women with diabetes had a 58% greater risk of coronary heart disease (CHD) mortality, but only an 8% greater risk of stroke mortality (RRR_CHD 1.58, 95% CI 1.32 to 1.90; P < 0.001; RRR_stroke 1.08, 95% CI 1.01 to 1.15; P < 0.001). However, no sex differences were observed in pooled results of populations with or without diabetes for all-cancer (RRR 1.02, 95% CI 0.98 to 1.06; P = 0.21), infectious (RRR 1.13, 95% CI 0.90 to 1.38; P = 0.33), and respiratory mortality (RRR 1.08, 95% CI 0.95 to 1.23; P = 0.26).

CONCLUSIONS

Compared with men with the same condition, women with diabetes have a 58% and 13% greater risk of CHD and all-cause mortality, respectively, although there was a significant heterogeneity between studies. This points to an urgent need to develop sex- and gender-specific risk assessment strategies and therapeutic interventions that target diabetes management in the context of CHD prevention.

Prognostic value of small nuclear RNAs (snRNAs) for digestive tract pan- adenocarcinomas identified by RNA sequencing data

Malignant tumors of the digestive tract include esophageal, gastric, and colorectal carcinomas, which all have high global mortality rates. A clinical role for small nuclear RNA (snRNA), a type of small non-coding RNA, has not yet been documented for digestive tract pan-adenocarcinomas. Therefore, the aim of the study was to identify differentially expressed snRNAs and to explore their prognostic implications in pan-adenocarcinomas from the esophagus, stomach, colon, and rectum. The pan-carcinoma RNA-sequencing data of four types of digestive tract cancers with 1, 102 cases obtained from The Cancer Genome Atlas (TCGA) project were analyzed and the differentially expressed snRNAs were evaluated using the edgeR package. The prognostic value of each of the selected snRNAs was determined by univariate and multivariate Cox regression analyses. All the digestive tract pan-adenocarcinomas showed differential expression of three snRNAs: the up-regulated RNU1-106 P and RNU6-850 P and the down-regulated RNU6-529 P. Interestingly, RNU6-101 P appeared to be a risk factor for esophageal adenocarcinoma (ESAD) and RNVU1-4 was potentially a protective factor for stomach adenocarcinoma (STAD) survival. This consistent finding of differential expression of all three snRNAs in all four types of digestive system cancers suggests potential roles for these snRNAs in the tumorigenesis of digestive system cancers. RNU6-101 P could play a pivotal role in the progression of ESAD and RNVU1-4 could perform a protective role in STAD. However, since the current findings were based on RNA-sequencing data mining, more studies are needed for verification.