The Protective Effect of Low-Dose Aspirin against Colorectal Cancer Is Unlikely Explained by Selection Bias: Results from Three Different Study Designs in Clinical Practice

Risk Factors and Prevention of Cancer and CVDs: A Chicken and Egg Situation

Cardiovascular diseases and cancer are the two primary causes of mortality worldwide. Although traditionally regarded as distinct pathologies, they share numerous pathophysiological mechanisms and risk factors, including chronic inflammation, insulin resistance, obesity, and metabolic dysregulation. Notably, several cancers have been identified as closely linked to cardiovascular diseases, including lung, breast, prostate, and colorectal cancers, as well as hematological malignancies, such as leukemia and lymphoma. Additionally, renal and pancreatic cancers exhibit a significant association with cardiovascular complications, partly due to shared risk factors and the cardiotoxic effects of cancer therapies. Addressing the overlapping risk factors through lifestyle modifications-such as regular physical activity, a balanced diet, and cessation of smoking and alcohol-has proven effective in reducing both CV and oncological morbidity and mortality. Furthermore, even in patients with established cancer, structured interventions targeting physical activity, nutritional optimization, and smoking cessation have been associated with improved outcomes. Beyond lifestyle modifications, pharmacological strategies play a crucial role in the prevention of both diseases. Several cardiovascular medications, including statins, aspirin, beta-blockers, and metformin, exhibit pleiotropic effects that extend beyond their primary indications, demonstrating potential anti-neoplastic properties in preclinical and observational studies. Recently, novel therapeutic agents have garnered attention for their possible cardioprotective and metabolic benefits. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2is), initially developed for managing type 2 diabetes, have shown CV and renal protective effects, alongside emerging evidence of their role in modulating cancer-related metabolic pathways. Inclisiran, a small interfering RNA targeting PCSK9, effectively lowers LDL cholesterol and may contribute to reducing CV risk, with potential implications for tumor biology. Additionally, sacubitril/valsartan, an angiotensin receptor-neprilysin inhibitor, has revolutionized heart failure management by improving hemodynamic parameters and exerting anti-inflammatory effects that may have broader implications for chronic disease prevention. Given the intricate interplay between CVD and cancer, further research is essential to clarify the exact mechanisms linking these conditions and assessing the potential of CV therapies in cancer prevention. This review aims to examine shared risk factors, consider the role of pharmacological and lifestyle interventions, and emphasize crucial epidemiological and mechanistic insights into the intersection of CV and oncological health.

Aspirin for Colorectal Cancer Prevention: Age Matters

Further data from the Aspirin in Reducing Events in the Elderly (ASPREE) trial heightens the concern regarding aspirin use for colorectal cancer prevention in elderly subjects. A 95-variant colorectal cancer polygenic risk score (PRS) failed to identify a subset of elderly individuals who could have benefited from aspirin preventive activity. Further research to define predictive biomarkers of aspirin preventive activity is needed. Meanwhile, the use of aspirin for colorectal cancer prevention in the elderly becomes more questionable. See Cancer Prev Res 15(7):447-53.

Safety and effectiveness of low-dose aspirin for the prevention of gastrointestinal cancer in adults without atherosclerotic cardiovascular disease: a population-based cohort study

OBJECTIVE

To assess the association between low-dose aspirin and the incidence of colorectal cancer (CRC), gastric cancer (GC), oesophageal cancer (EC) and gastrointestinal bleeding (GIB) in adults without established atherosclerotic cardiovascular disease.

DESIGN

Cohort study with propensity score matching of new-users of aspirin to non-users.

SETTING

Clinical Data Analysis and Reporting System database, Hong Kong.

PARTICIPANTS

Adults ≥40 years with a prescription start date of either low-dose aspirin (75-300 mg/daily) or paracetamol (non-aspirin users) between 1 January 2004 to 31 December 2008 without a history of atherosclerotic cardiovascular disease.

MAIN OUTCOME MEASURES

The primary outcome was the first diagnosis of gastrointestinal cancer (either CRC, GC or EC) and the secondary outcome was GIB. Individuals were followed from index date of prescription until the earliest occurrence of an outcome of interest, an incident diagnosis of any type of cancer besides the outcome, death or until 31 December 2017. A competing risk survival analysis was used to estimate HRs and 95% CIs with death as the competing risk.

RESULTS

After matching, 49 679 aspirin and non-aspirin users were included. The median (IQR) follow-up was 10.0 (6.4) years. HRs for low-dose aspirin compared with non-aspirin users were 0.83 for CRC (95% CI, 0.76 to 0.91), 0.77 for GC (95% CI, 0.65 to 0.92) and 0.88 for EC (95% CI, 0.67 to 1.16). Patients prescribed low-dose aspirin had an increased risk of GIB (HR 1.15, 95% CI, 1.11 to 1.20), except for patients prescribed proton pump inhibitors or histamine H2-receptor antagonists (HR 1.03, 95% CI, 0.96 to 1.10).

CONCLUSION

In this cohort study of Chinese adults, patients prescribed low-dose aspirin had reduced risks of CRC and GC and an increased risk of GIB. Among the subgroup of patients prescribed gastroprotective agents at baseline, however, the association with GIB was attenuated.

Aspirin for prevention of colorectal cancer in the elderly: friend or foe?

Cancer is the leading cause of death among men and women aged 60-79 years. Colorectal cancer is the third most common cancer in males and the second most common in females, with about 0.8 million deaths worldwide per year. Individuals older than 50 years account for 20-50% of colonic adenomas. Several measures have been proposed to decrease colorectal cancer risks, such as an increase in dietary fiber, use of aspirin, and physical activity. Nonsteroidal anti-inflammatory drugs have been proposed as protective agents against the development of colorectal cancer and colorectal adenomas. Aspirin was the first pharmacological agent endorsed by the United States Preventive Services Task Force screening for colorectal cancer chemoprevention. Although studies have shown up to 40% colorectal cancer risk reduction in individuals at average risk, data regarding this benefit are inconsistent. Several recent studies show that prophylactic use of aspirin in elderly subjects may not be beneficial in preventing the occurrence of colorectal cancers. Given the risks associated with aspirin, such as non-fatal and fatal bleeding events, aspirin's role should be redefined, especially in individuals at risk of bleeding. This review provides a discussion of the recent studies on the role of aspirin use in elderly individuals at risk of colorectal cancer.

An action plan to address the rising burden of colorectal cancer in younger adults

Aim: The National Colorectal Cancer Roundtable convened a national Summit to discuss the causes of early-onset colorectal cancer and clinical challenges to mitigating burden of this disease. Materials & methods: Information presented was synthesized through scientific consensus building to determine priorities for new research and practice change. Results: Research priorities include evaluating role of novel risk factors, understanding natural history and identifying ways to implement evidenced-based practices for identifying and managing at-risk persons. Practice change should focus on adoption of guidelines for collecting family history, screening in young adults at risk, provider and population awareness about risk and symptoms, and universal tumor testing. Conclusion: Successful implementation of strategies to address research and practice change will require collaboration from multiple partners.

Metabolic dysfunction and early-onset colorectal cancer - how macrophages build the bridge

Background

The incidence of colorectal cancer (CRC) among patients <50 years of age has increased dramatically over the last decades. At the same time, the growing proportion of obese children and adolescents and the increasing proportion of young and obese patients with CRC suggests an association between metabolic dysfunction and carcinogenesis. Tumor‐associated macrophages (TAMs) are able to orchestrate tumor promoting and suppressing mechanisms in CRC. The aim of this review was to discuss the different roles of TAMs in CRC and their phenotype‐specific metabolic pathways to identify potential new targets for CRC treatment.

Methods

A literature search was performed using PubMed, Cochrane and Embase to identify studies on TAMs and their metabolism in CRC. The following search terms were used in various combinations: (obesity OR adiposity OR obese) AND (macrophage OR polarization OR macrophage metabolism) AND ((colon cancer*) OR (colon carcinoma) OR (colonic tumor*) OR (colonic neoplasm[MeSH]) OR (rectal cancer*) OR (rectal carcinoma) OR (rectal tumor*) OR (rectal neoplasm[MeSH]) OR (colorectal cancer*) OR (colorectal carcinoma) OR (colorectal tumor*) OR (colorectal neoplasm[MeSH])). Studies including data on the phenotype and metabolism of TAMs in CRC were analyzed.

Results

Evidence for the prognostic utility of macrophage markers in CRC is currently evolving, with a particular role of stage‐dependent cellular metabolism profiles of TAMs. Itaconate is one of the metabolites produced by proinflammatory subtypes of TAMs and it is known to have tumor promoting effects. Metabolic pathways that are involved in macrophage activation and reprogramming play a role in a chronic inflammatory setting, consequently affecting the onset and development of CRC.

Conclusions

Tumor‐promoting metabolites, such as itaconate, are directly regulating these mechanisms, thereby triggering carcinogenesis. Metabolic reprogramming in TAMs can build a bridge between metabolic dysfunction and the onset and progression of CRC through inflammatory pathways, particularly in younger patients with early‐onset CRC.

Association of Aspirin and Nonsteroidal Anti-Inflammatory Drugs With Colorectal Cancer Risk by Molecular Subtypes

BACKGROUND

Regular use of aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) for a longer period has been inversely associated with colorectal cancer (CRC) risk. However, CRC is a heterogenic disease, and little is known regarding the associations with molecular pathological subtypes.

METHODS

Analyses included 2444 cases with a first diagnosis of CRC and 3130 healthy controls from a German population-based case control study. Tumor tissue samples were analyzed for major molecular pathological features: microsatellite instability (MSI), CpG island methylator phenotype, B-Raf proto-oncogene serine/threonine kinase (BRAF) mutation, and Kirsten rat sarcoma viral oncogene homolog gene (KRAS) mutation. Information on past and current use of NSAIDs, including aspirin, was obtained by standardized interviews. Multinomial logistic regression models were used to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). All statistical tests were two-sided.

RESULTS

Regular use of NSAIDs was associated with a reduced CRC risk if tumors were MSS (OR = 0.66, 95% CI = 0.57 to 0.77), BRAF wildtype (OR = 0.67, 95% CI = 0.58 to 0.78), or KRAS wildtype (OR = 0.68, 95% CI = 0.58 to 0.80). Regular NSAID use was less clearly and mostly not statistically significantly associated with CRC risk reduction for MSI-high, BRAF-mutated, or KRAS-mutated CRC. In more specific analyses on MSI-high CRC, regular use of NSAIDs was associated with much stronger risk reduction in the absence of BRAF or KRAS mutations (OR = 0.34, 95% CI = 0.18 to 0.65) but not with KRAS- or BRAF-mutated MSI-high CRC (Pheterogeneity < .001). Results for just aspirin use were similar.

CONCLUSION

Our study suggests variation in risk reduction of CRC subtypes following regular use of NSAIDs and aspirin. Regular use of NSAIDs and aspirin may be more strongly associated with risk reduction of MSI-high CRC without KRAS or BRAF mutation.

Low-dose aspirin and risk of gastric and oesophageal cancer: A population-based study in the United Kingdom using The Health Improvement Network

There is increasing interest regarding potential protective effects of low‐dose aspirin against various gastrointestinal cancers. We aimed to quantify the association between use of low‐dose aspirin and risk of gastric/oesophageal cancer using a population‐based primary care database in the UK. Between January 2005 and December 2015, we identified a cohort of 223 640 new users of low‐dose aspirin (75‐300 mg/day) and a matched cohort of nonusers at the start of follow‐up from The Health Improvement Network. Cohorts were followed to identify incident cases of gastric/oesophageal cancer. Nested case‐control analyses were conducted and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for current vs nonuse of low‐dose aspirin using logistic regression. Current use was defined as when low‐dose aspirin lasted 0 to 90 days before the index date (event date for cases, random date for controls) and previous duration was ≥1 year. We identified 727 incident cases of gastric cancer and 1394 incident cases of oesophageal cancer. ORs (95% CIs) were 0.46 (0.38‐0.57) for gastric cancer and 0.59 (0.51‐0.69) for oesophageal cancer. The effect remained consistent with no clear change seen between previous duration of low‐dose aspirin use of 1‐3, 3‐5 or >5 years. The reduced risks was seen with 75 mg/day, and effects were consistent in lag‐time analyses. In conclusion, our results indicate that use of low‐dose aspirin is associated with a 54% reduced risk of gastric cancer and a 41% reduced risk of oesophageal cancer as supported by mechanistic data.

What's new?

Low‐dose aspirin may help protect against the development of gastric and oesophageal cancers. This population‐based study using data from primary care electronic health records in the United Kingdom lends further support to that idea. Compared with no use of low‐dose aspirin, daily use of low‐dose aspirin (75–300 mg) for at least one year was associated with a 54 percent reduction in gastric cancer risk and a 41 percent reduction in oesophageal cancer risk. No clear difference in effect was observed between low‐dose aspirin use for one to three years versus more than three years.

No association between use of phosphodiesterase 5 inhibitors and colorectal cancer in men with erectile dysfunction

PURPOSE

There is an increase interest on the potential chemoprotective effect of selective phosphodiesterase 5 (PDE5) inhibitors. Several authors have shown in vivo the immune-mediated anti-tumor effect of these inhibitors on tumors arising from the digestive tract.

OBJECTIVES

To test the potential effect of selective PDE5 inhibitors against colorectal cancer (CRC) onset previously observed.

METHODS

We used data from The Health Improvement Network database and identified an established cohort of 200 000 new users of low-dose aspirin and a matched comparison cohort aged 40-84 years between 1 January 2000 and 31 December 2011. A follow-up to identify CRC cases was performed within an extensive validation exercise. Nested case-control analyses compared PDE5 inhibitors vs non-use on CRC risk were performed.

RESULTS

Restricting to males (59.3% controls and 59.5% cases), no association was observed among current users of PDE5 inhibitors (1.05 [95% CI: 0.69-1.60]) and neither among recent (1.36 [95% CI: 0.81-2.28]) or past users (1.06 [95% CI: 0.72-1.58]). No duration response effect was found.

CONCLUSIONS

Our results do not support an increased risk of CRC associated with the use of PDE5 inhibitors among men with erectile dysfunction.

The effect of low-dose aspirin on colorectal cancer prevention and gastrointestinal bleeding according to bodyweight and body mass index: Analysis of UK primary care data

BACKGROUND

Meta-analysis of trial data suggests that in primary cardiovascular disease (CVD) prevention bodyweight modifies low-dose aspirin's effects on colorectal cancer (CRC) and major bleeding risk. We sought to investigate whether these effects are seen in patients with or without CVD in routine clinical practice by undertaking sub-analyses of data from two cohort studies with nested-case-control analyses.

METHODS

We followed ~200,000 new users of low-dose aspirin (75-300 mg/day) and a matched cohort of non-users to identify incident cases of CRC/upper gastrointestinal bleeding (UGIB). Adjusted relative risks (RRs) with 95% confidence intervals (CIs) were calculated for current vs. non-use of low-dose aspirin using logistic regression stratified by bodyweight/body mass index (BMI) strata.

RESULTS

RRs (95% CIs) for CRC by bodyweight were: 0.60 (0.50-0.72) for ≤70 kg, 0.68 (0.60-0.76) for >70 kg; and by BMI were 0.60 (0.52-0.68) for ≤28 kg/m², 0.76 (0.64-0.89) for >28 kg/m². For UGIB, estimates were: 1.49 (1.28-1.74) for ≤90 kg, 1.78 (1.29-2.45) for >90 kg/m², 1.44 (1.21-1.72) for ≤28 kg/m², 1.72 (1.38-2.16) for >28 kg/m². Results were similar in the primary CVD prevention population.

CONCLUSION

Our findings suggest that the effects of low-dose aspirin in reducing CRC risk and increasing UGIB risk are not modified by bodyweight/BMI.

Reviewing the role of P2Y receptors in specific gastrointestinal cancers

Extracellular nucleotides are important intercellular signaling molecules that were found enriched in the tumor microenvironment. In fact, interfering with G protein-coupled P2Y receptor signaling has emerged as a promising therapeutic alternative to treat aggressive and difficult-to-manage cancers such as those affecting the gastrointestinal system. In this review, we will discuss the functions of P2Y receptors in gastrointestinal cancers with an emphasis on colorectal, hepatic, and pancreatic cancers. We will show that P2Y2 receptor up-regulation increases cancer cell proliferation, tumor growth, and metastasis in almost all studied gastrointestinal cancers. In contrast, we will present P2Y6 receptor as having opposing roles in colorectal cancer vs. gastric cancer. In colorectal cancer, the P2Y6 receptor induces carcinogenesis by inhibiting apoptosis, whereas P2Y6 suppresses gastric cancer tumor growth by reducing β-catenin transcriptional activity. The contribution of the P2Y11 receptor in the migration of liver and pancreatic cancer cells will be compared to its normal inhibitory function on this cellular process in ciliated cholangiocytes. Hence, we will demonstrate that the selective inhibition of the P2Y12 receptor activity in platelets was associated to a reduction in the risk of developing colorectal cancer and metastasis formation. We will succinctly review the role of P2Y1, P2Y4, P2Y13, and P2Y14 receptors as the knowledge for these receptors in gastrointestinal cancers is sparse. Finally, redundant ligand selectivity, nucleotide high lability, cell context, and antibody reliability will be presented as the main difficulties in defining P2Y receptor functions in gastrointestinal cancers.

Antiplatelet Agents for Cancer Prevention: Current Evidences and Continuing Controversies

Over the past two decades, aspirin has emerged as a promising chemoprotective agent to prevent colorectal cancer (CRC). In 2016, the mounting evidence supporting its chemoprotective effect, from both basic science and clinical research, led the US Preventive Services Task Force to recommend regular use of low-dose aspirin in some subgroups of patients for whom the benefits are deemed to outweigh the risks. In contrast, data on the chemoprotective effect of aspirin against other cancers are less clear and remain controversial. Most data come from secondary analyses of cardiovascular prevention trials, with only a limited number reporting cancer outcomes as a prespecified endpoint, and overall unclear findings. Moreover, the potential chemoprotective effect of aspirin against other cancers has been recently questioned with the publication of 3 long-awaited trials of aspirin in the primary prevention of cardiovascular diseases reporting no benefit of aspirin on overall cancer incidence and cancer-related mortality. Data on the chemoprotective effects of other antiplatelet agents remain scarce and inconclusive, and further research to examine their benefit are warranted. In this narrative review, we summarize current clinical evidence and continuing controversies on the potential chemoprotective properties of antiplatelet agents against cancer.

Effects of Aspirin or Clopidogrel on Colorectal Cancer Chemoprevention in Patients with Type 2 Diabetes Mellitus

Background: The effect of clopidogrel, whose mechanism of action differs from that of aspirin, on CRC risk remains unknown. We investigated the effects of clopidogrel and aspirin, either as monotherapy or combined, on colorectal cancer (CRC) risk in patients with Type 2 diabetes mellitus (T2DM). Methods: We conducted a cohort study using Taiwan National Health Insurance Research Database. Four groups comprising 218,903 patients using aspirin monotherapy, 20,158 patients using clopidogrel monotherapy, 42,779 patients using dual antiplatelet therapy, and 281,840 nonuser matched controls were created using propensity score matching. Cox proportional hazards regression was used to evaluate the CRC risk during follow-up. Results: During the 13-year follow-up period, we found 9431 cases of CRC over 3,409,522 person-years. The overall incidence rates of CRC were 2.04, 3.45, 1.55, and 3.52 per 1000 person-years in the aspirin, clopidogrel, dual antiplatelet, and nonuser cohorts, respectively. The adjusted hazard ratios (aHRs) were 0.59 (95% confidence interval [CI], 0.56–0.61), 0.77 (95% CI, 0.68–0.87), and 0.37 (95% CI, 0.33–0.40) for the aspirin, clopidogrel, and dual antiplatelet cohorts, respectively. Dose- and duration-dependent chemopreventive effects were observed in the three cohorts.

Clopidogrel and Low-Dose Aspirin, Alone or Together, Reduce Risk of Colorectal Cancer

BACKGROUND & AIMS

The antiplatelet effect of low-dose aspirin, via inhibition of cyclooxygenase-1, might contribute to its ability to reduce the risk of colorectal cancer (CRC). Antiplatelet agents with a different mechanism, such as clopidogrel, might have the same effects. We aimed to quantify the effects of low-dose aspirin and clopidogrel on the risk of CRC in a Mediterranean population.

METHODS

We performed a nested case-control study using a primary care database (Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria) in Spain. We collected data, from 2001 through 2014, on 15,491 incident cases of CRC and 60,000 randomly selected individuals (controls), frequency-matched to cases by age, sex, and year. To estimate the association between exposure to different antiplatelet agents and the risk of colorectal cancer, we built multiple logistic regression models and computed the adjusted-odds ratios (AORs) and their respective 95% CIs.

RESULTS

Use of low-dose aspirin was associated with a reduced risk of CRC overall (AOR, 0.83; 95% CI, 0.78-0.89) and in patients receiving treatment for more than 1 year (AOR, 0.79; 95% CI, 0.73-0.85). Use of clopidogrel was associated with a decreased risk of CRC overall (AOR, 0.8; 95% CI, 0.69-0.93) and in patients receiving treatment for more than 1 year (AOR, 0.65; 95% CI, 0.55-0.78). Dual antiplatelet therapy had the same effect as either drug taken as monotherapy. No modification by sex or age was observed.

CONCLUSIONS

In a nested case-control study of a primary care database in Spain, we found clopidogrel use, alone or in combination with low-dose aspirin, to reduce the risk of CRC by 20% to 30%, a magnitude similar to that of low-dose aspirin alone. These data support the concept that inhibiting platelets is an effective strategy for prevention of CRC.

Incidence of Upper and Lower Gastrointestinal Bleeding in New Users of Low-Dose Aspirin

BACKGROUND & AIMS

There are few data on the incidence of upper and lower gastrointestinal bleeding (UGIB and LGIB) from observational studies of low-dose aspirin users. We aimed to estimate incidence rates of UGIB and LGIB in a large cohort of new users of low-dose aspirin in the United Kingdom, with subanalyses of hospitalization status and fatalities.

METHODS

We performed a population-based study of 199,079 new users of low-dose aspirin (median age, 64.0 years) identified from the Health Improvement Network primary care database (2000-2012). Individuals were followed for a median 5.4 years (maximum, 14 years) to identify new cases of UGIB and LGIB. Following multistep validation, we calculated overall and age- and sex-specific incidence rates; we performed subanalyses for health care use and death within 30 days of GIB. We also estimated rates within a matched (1:1) cohort of nonusers of low-dose aspirin at the start of the follow-up period.

RESULTS

The low-dose aspirin users had 1115 UGIB events and 1936 LGIB events; most subjects with UGIB events (58.9%) were hospitalized, whereas most subjects with LGIB events were referred to secondary care (72.8%). Crude incidence rates of GIB per 1000 person-years were 0.97 for subjects with UGIB (95% CI, 0.91-1.02) and 1.68 for subjects with LGIB (95% CI, 1.60-1.75). Incidence rates per 1000 person-years for patients hospitalized for GIB were 0.57 for UGIB (95% CI, 0.53-0.61) and 0.45 for LGIB (95% CI, 0.42-0.49); for referred (but not hospitalized) cases, these values were 0.39 for UGIB (95% CI, 0.36-0.43) and 1.22 for LGIB (1.16-1.29). Incidence rates per 1000 person-years were 0.06 for fatal UGIB (95% CI, 0.04-0.07), 0.01 for fatal LGIB (95% CI, 0.01-0.02), 0.91 for nonfatal UGIB (95% CI, 0.86-0.97), and 1.66 for nonfatal LGIB (95% CI, 1.59-1.74). Among nonusers of low-dose aspirin, incidence rates per 1000 person-years were 0.67 (95% CI, 0.63-0.75) for UGIB and 0.76 (95% CI, 0.72-0.82) for LGIB.

CONCLUSION

In a population-based study of low-dose aspirin users, the incidence of LGIB was higher than the incidence of UGIB. However, incidence rates of hospitalized GI bleeds and 30-day mortality rates were lower for LGIB than for UGIB. These estimates are valuable for benefit-risk assessments of low-dose aspirin for cardiovascular and colorectal cancer prevention.

Conditions Associated with Essential Tremor in Veterans: A Potential Role for Chronic Stress

Background

Increased depression, hearing loss, dementia, alcoholism, and mortality in essential tremor patients remain unexplained. We investigated whether conditions associated with tremor are linked to chronic stress.

Methods

The FY2013 Veterans Affairs database was queried for 38 selected dual diagnosis combinations in 5,854,223 veterans aged 21–95 years.

Results

Post-traumatic stress disorder, anxiety, and depression were the most common psychiatric diagnoses in tremor patients, with the odds ratio exceeding 2 in all 15-year cohorts. Depending on age, patients with essential tremor were more likely than those without to have obsessive–compulsive disorder, bipolar illness, schizophrenia, use tobacco and abuse alcohol, have hypertension, obesity, hyperlipidemia, diabetes, vitamin D deficiency, coronary and cerebrovascular diseases, congestive heart failure, stroke, asthma, hypothyroidism, irritable bowel syndrome, renal insufficiency, alcoholic liver disease, hearing loss, glaucoma, macular degeneration, migraine, epilepsy, idiopathic polyneuropathy, history of head trauma, and ‘Alzheimer’s dementia. In contrast, lung and colorectal cancer, amyotrophic lateral sclerosis, psychostimulant abuse, and rheumatoid arthritis were not more common.

Discussion

Post-traumatic stress disorder, anxiety, and depression, strongly associated with essential tremor, are known risk factors for poor health habits, tobacco use and alcohol abuse; collectively these are risk factors for vascular disease, with further negative health consequences for multiple organ systems. As essential tremor is associated with all these conditions, we propose that chronic stress is not only responsible for the conditions associated with tremor but in some cases itself directly and indirectly induces essential tremor, so that tremor and poor health share a common cause.

Associations between aspirin use and the risk of cancers: a meta-analysis of observational studies

Background

Epidemiological studies have clarified the potential associations between regular aspirin use and cancers. However, it remains controversial on whether aspirin use decreases the risk of cancers risks. Therefore, we conducted an updated meta-analysis to assess the associations between aspirin use and cancers.

Methods

The PubMed, Embase, and Web of Science databases were systematically searched up to March 2017 to identify relevant studies. Relative risks (RRs) with 95% confidence intervals (CIs) were used to assess the strength of associations.

Results

A total of 218 studies with 309 reports were eligible for this meta-analysis. Aspirin use was associated with a significant decrease in the risk of overall cancer (RR = 0.89, 95% CI: 0.87–0.91), and gastric (RR = 0.75, 95% CI: 0.65–0.86), esophageal (RR = 0.75, 95% CI: 0.62–0.89), colorectal (RR = 0.79, 95% CI: 0.74–0.85), pancreatic (RR = 0.80, 95% CI: 0.68–0.93), ovarian (RR = 0.89, 95% CI: 0.83–0.95), endometrial (RR = 0.92, 95% CI: 0.85–0.99), breast (RR = 0.92, 95% CI: 0.88–0.96), and prostate (RR = 0.94, 95% CI: 0.90–0.99) cancers, as well as small intestine neuroendocrine tumors (RR = 0.17, 95% CI: 0.05–0.58).

Conclusions

These findings suggest that aspirin use is associated with a reduced risk of gastric, esophageal, colorectal, pancreatic, ovarian, endometrial, breast, and prostate cancers, and small intestine neuroendocrine tumors.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4156-5) contains supplementary material, which is available to authorized users.

Incidence of colorectal cancer in new users and non-users of low-dose aspirin without existing cardiovascular disease: A cohort study using The Health Improvement Network

BACKGROUND

Evidence regarding the chemo-protective effects of aspirin has influenced expert opinion in favour of low-dose aspirin use in certain patient populations without cardiovascular disease (CVD). The effects of aspirin in reducing the incidence of colorectal cancer (CRC) may be a large contributor to this favourable risk-benefit profile of low-dose aspirin in primary CVD prevention.

METHODS

Using The Health Improvement Network, we estimated the incidence of CRC in individuals free of CVD and either prescribed or not prescribed prophylactic low-dose aspirin. Two cohorts - new-users of low-dose aspirin (N=109,426) and a comparator cohort of non-users (N=154,056) at start of follow-up - were followed (maximum 13years) to identify incident CRC cases. Individuals with a record of CVD, cancer or low-dose aspirin prescription before start of follow-up were excluded.

RESULTS

2330 incident cases of CRC occurred; 885 in the aspirin cohort and 1445 in the comparator cohort, after mean follow-ups of 5.43years and 5.17years, respectively. Incidence rates of CRC per 10,000 person-years (95% confidence interval) were 14.90 (13.95-15.92) in the aspirin cohort and 18.15 (17.24-19.12) in the comparator cohort; incidence rate ratio 0.82 (0.76-0.89) adjusted for age, sex and primary care practitioner (PCP) visits in the previous year. Lower incidence rates were seen in the aspirin cohort for all strata evaluated (gender, age group and number of PCP visits in the previous year) except those aged ≥80years.

CONCLUSION

Among most individuals without established CVD, initiation of low-dose aspirin is associated with a reduced incidence of CRC.

Low-dose aspirin and risk of intracranial bleeds

Objective:

To quantify the risk of intracranial bleeds (ICBs) associated with new use of prophylactic low-dose aspirin using a population-based primary care database in the United Kingdom.

Methods:

A cohort of new users of low-dose aspirin (75–300 mg; n = 199,079) aged 40–84 years and a 1:1 matched cohort of nonusers of low-dose aspirin at baseline were followed (maximum 14 years, median 5.4 years) to identify incident cases of ICB, with validation by manual review of patient records or linkage to hospitalization data. Using 10,000 frequency-matched controls, adjusted rate ratios (RRs) with 95% confidence intervals (CIs) were calculated for current low-dose aspirin use (0–7 days before the index date [ICB date for cases, random date for controls]); reference group was never used.

Results:

There were 1,611 cases of ICB (n = 743 for intracerebral hemorrhage [ICH], n = 483 for subdural hematoma [SDH], and n = 385 for subarachnoid hemorrhage [SAH]). RRs (95% CI) were 0.98 (0.84–1.13) for all ICB, 0.98 (0.80–1.20) for ICH, 1.23 (0.95–1.59) for SDH, and 0.77 (0.58–1.01) for SAH. No duration of use or dose–response association was apparent. RRs (95% CI) for ≥1 year of low-dose aspirin use were 0.90 (0.72–1.13) for ICH, 1.20 (0.91–1.57) for SDH, and 0.69 (0.50–0.94) for SAH.

Conclusion:

Low-dose aspirin is not associated with an increased risk of any type of ICB and is associated with a significantly decreased risk of SAH when used for ≥1 year.

Chemoprevention by artesunate in a preclinical model of colorectal cancer involves down regulation of β-catenin, suppression of angiogenesis, cellular proliferation and induction of apoptosis

Use of anti-inflammatory drugs is well known to decrease the risk of colorectal cancer, one of the most common causes of cancer related mortality. In view of anti-inflammatory property of artesunate reported in various experimental models, the present study was carried out to evaluate its efficacy in rat model where colon carcinogenesis was induced by 1, 2 dimethylhydrazine (DMH). A time course study revealed that two injections of DMH given at an interval of one week resulted in appearance of multiple plaque lesions and aberrant crypt foci in the colon with a peak effect occurring at the end of 8 weeks. An efficacy study carried out with daily oral administration of artesunate (50 and 150 mg/kg) and aspirin (60 mg/kg) showed a marked reduction in pre-neoplastic changes with a significant decrease in the number of aberrant crypt foci, crypt multiplicity and restoration of histoarchitecture. Both the drugs down regulated β-catenin signaling, reduced the levels of angiogenic markers like VEGF, MMP-9 and inhibited cellular proliferation. The anti-cancer effect of these drugs was concomitant with the pro-apoptotic effect as revealed by increased DNA fragmentation, TUNEL positivity and Bax/Bcl₂ immunoreactivity. This is the first study to evaluate the inhibitory effect of artesunate on pre-neoplastic changes in colon where its chemopreventive effect was found to be comparable to that of aspirin. Our study strengthens the previous findings and shows that it has a preventive and therapeutic potential in the treatment of colon cancer.

New use of low-dose aspirin and risk of colorectal cancer by stage at diagnosis: a nested case-control study in UK general practice

Background

Evidence from clinical trial populations suggests low-dose aspirin reduces the risk of colorectal cancer (CRC). Part of this reduction in risk might be due to protection against metastatic disease.

Methods

We investigated the risk of CRC among new-users of low-dose aspirin (75–300 mg), including risk by stage at diagnosis. Using The Health Improvement Network, we conducted a cohort study with nested case–control analysis. Two cohorts (N = 170,336 each) aged 40–89 years from 2000 to 2009 and free of cancer were identified: i) new-users of low-dose aspirin, ii) non-users of low-dose aspirin, at start of follow-up, matched by age, sex and previous primary care practitioner visits. Patients were followed for up to 12 years to identify incident CRC. 10,000 frequency-matched controls were selected by incidence density sampling where the odds ratio is an unbiased estimator of the incidence rate ratio (RR). RRs with 95% confidence intervals were calculated. Low-dose aspirin use was classified ‘as-treated’ independent from baseline exposure status to account for changes in exposure during follow-up.

Results

Current users of low-dose aspirin (use on the index date or in the previous 90 days) had a significantly reduced risk of CRC, RR 0.66 (95% CI 0.60–0.74). The reduction in risk was apparent across all age groups, and was unrelated to dose, indication, gender, CRC location or case-fatality status. Reduced risks occurred throughout treatment duration and with all low-dose aspirin doses. RRs by aspirin indication were 0.71 (0·63–0·79) and 0.60 (0.53–0.68) for primary and secondary cardiovascular protection, respectively. Among cases with staging information (n = 1421), RRs for current use of low-dose aspirin were 0.94 (0.66–1.33) for Dukes Stage A CRC, 0.54 (0.42–0.68) for Dukes B, 0.71 (0.56–0.91) for Dukes C, and 0.60 (0.48–0.74) for Dukes D. After 5 years’ therapy, the RR for Dukes Stage A CRC was 0.53 (0.24–1.19).

Conclusions

Patients starting low-dose aspirin therapy have a reduced risk of Stages B–D CRC, suggesting a role for low-dose aspirin in the progression of established CRC; a substantial reduction in the risk of Dukes A CRC may occur after 5 years’ therapy.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3594-9) contains supplementary material, which is available to authorized users.

Incidence of intracranial bleeds in new users of low-dose aspirin: a cohort study using The Health Improvement Network

Essentials Intracranial bleeds (ICB) are serious clinical events that have been associated with aspirin use. Incidence rates of ICB were calculated among new-users of low-dose aspirin in the UK (2000-2012). Over a median follow-up of 5.58 years, the incidence of ICB was 0.08 per 100 person-years. Our estimates are valuable for inclusion in risk-benefit assessments of low-dose aspirin use.

SUMMARY

Background Low-dose aspirin protects against both ischemic cardiovascular (CV) events and colorectal cancer (CRC). However, low-dose aspirin may be associated with a slightly increased risk of intracranial bleeds (ICBs). Objectives To obtain the incidence rates of ICBs overall and by patient subgroups among new users of low-dose aspirin. Patients/Methods Using The Health Improvement Network (THIN) UK primary-care database (2000-2012), we identified a cohort of new users of low-dose aspirin aged 40-84 years (N = 199 079; mean age at start of follow-up, 63.9 years) and followed them for up to 14 years (median 5.58 years). Incident ICB cases were identified and validated through linkage to hospitalization data and/or review of THIN records with free-text comments. Incidence rates with 95% confidence intervals (CIs) were calculated. Results Eight hundred and eighty-one incident ICBs cases were identified: 407 cases of intracerebral hemorrhage (ICH), 283 cases of subdural hematoma (SDH), and 191 cases of subarachnoid hemorrhage (SAH). Incidence rates per 100 person-years were 0.08 (95% CI 0.07-0.08) for all ICBs, 0.04 (95% CI 0.03-0.04) for ICH, 0.03 (95% CI 0.02-0.03) for SDH, and 0.02 (95% CI 0.01-0.02) for SAH. The ICB incidence rates per 100 person-years for individuals with an indication of primary CV disease prevention were 0.07 (95% CI 0.06-0.07) and 0.09 (95% CI 0.08-0.10) for secondary CV disease prevention. Incidence rates were higher in men for SDH, and higher in women for ICH and SAH. Conclusions Our results provide valuable estimates of the absolute ICB risk for incorporation into risk-benefit assessments of low-dose aspirin use.

Prevention and treatment of cancer targeting chronic inflammation: research progress, potential agents, clinical studies and mechanisms

Numerous experimental and clinical studies indicate that chronic inflammation is closely related to the initiation, progression, and spread of cancer, in which proinflammatory cytokines, such as interleukin (IL)-6, IL-1β, and tumor necrosis factor-α (TNF-α), and transcription factors, such as nuclear factor-κB (NF-κB), and signal transducer and activator of transcription 3 (STAT3), play pivotal roles. Stimulated by proinflammatory cytokines, NF-κB and STAT3 can modulate the expression of target genes, most of which are oncogenic ones, and promote the survival, proliferation, invasion, and metastasis of cancer cells. Now it is generally accepted that inflammation-related molecules and pathways are useful targets for the prevention and treatment of cancer. In this review, we summarize the relationship between chronic inflammation and cancer and describe some potentially useful agents including aspirin, meformin, statins, and some natural products (green tea catechins, andrographolide, curcumin) for their cancer prevention and treatment activities targeting chronic inflammation. The results of typical clinical studies are included, and the influences of these agents on the proinflammatory cytokines and inflammation-related pathways are discussed. Data from the present review support that agents targeting chronic inflammation may have a broad application prospect for the prevention and treatment of cancer in the future.

Metformin therapy and the risk of colorectal adenoma in patients with type 2 diabetes: A meta-analysis

BACKGROUND

Existing data evaluating the impact of metformin on the colorectal adenoma (CRA) risk in patients suffering from type 2 diabetes (T2D) are limited and controversial. We therefore summarized the studies currently available and assessed the relationship between metformin treatment and risk of CRA in T2D patients.

METHODS

We systematically searched databases for eligible studies that explored the impact of metformin treatment on the occurrence of CRA in T2D patients from inception to June 2016. The summary odds ratio (OR) estimates with their 95% confidence interval (CI) were derived using random-effect, generic inverse variance methods. Sensitivity analysis and subgroup analysis were performed.

RESULTS

Seven studies involving 7178 participants met the inclusion criteria. The pooling showed that metformin therapy has a 27% decrease in the CRA risk (OR, 0.73; 95% CI, 0.58 - 0.90). In subgroup analysis, we detected that metformin exhibits significant chemoprevention effects in Asia region (OR, 0.68; 95% CI, 0.48 - 0.96). Similar results were identified in both studies with adjusted ORs and high-quality studies (OR, 0.66; 95% CI, 0.50 - 0.86 and OR, 0.70; 95% CI, 0.58 - 0.84, respectively). Of note, an inverse relationship was noted that metformin therapy may result in a significant decrease in the advanced adenoma risk (OR, 0.52; 95% CI, 0.38 - 0.72). Low heterogeneity was observed, however, the results remained robust in multiple sensitivity analyses.

CONCLUSIONS

This meta-analysis indicates that metformin therapy is correlated with a significant decrease in the risk of CRA and advanced adenoma in T2D patients. Further confirmatory studies are warranted.