Proton pump inhibitors and risk of periampullary cancers--A nested case-control study

The State of Use and Utility of Negative Controls in Pharmacoepidemiologic Studies

Uses of real-world data in drug safety and effectiveness studies are often challenged by various sources of bias. We undertook a systematic search of the published literature through September 2020 to evaluate the state of use and utility of negative controls to address bias in pharmacoepidemiologic studies. Two reviewers independently evaluated study eligibility and abstracted data. Our search identified 184 eligible studies for inclusion. Cohort studies (115, 63%) and administrative data (114, 62%) were, respectively, the most common study design and data type used. Most studies used negative control outcomes (91, 50%), and for most studies the target source of bias was unmeasured confounding (93, 51%). We identified 4 utility domains of negative controls: 1) bias detection (149, 81%), 2) bias correction (16, 9%), 3) P-value calibration (8, 4%), and 4) performance assessment of different methods used in drug safety studies (31, 17%). The most popular methodologies used were the 95% confidence interval and P-value calibration. In addition, we identified 2 reference sets with structured steps to check the causality assumption of the negative control. While negative controls are powerful tools in bias detection, we found many studies lacked checking the underlying assumptions. This article is part of a Special Collection on Pharmacoepidemiology.

Association between proton-pump inhibitors and the risk of gastric cancer: a systematic review and meta-analysis

BACKGROUND

Proton pump inhibitors (PPIs) may be associated with gastric cancer, but studies in recent years have proven still inconsistent results. We conducted a systematic review and meta-analysis to investigate the association between PPI use and gastric cancer.

METHODS

Pubmed, EMBASE, and Cochrane library were searched for studies published up to 15th February 2022. Studies on the association between PPI and the risk of gastric cancer, pooled the odds ratios (ORs) using a random-effects model. The subgroup analysis for study design, site of gastric cancer, and the duration of PPI use was performed. Heterogeneity was assessed using the I² and Cochran's Q statistics.

RESULTS

Sixteen cohorts and case-control studies were included. PPI use was significantly associated with gastric cancer (OR: 1.75, 95% CI: 1.28-2.40). The subgroup analysis found a significant risk increase in non-cardia gastric cancer (OR: 2.14, 95%CI: 1.50-3.07). There was no duration-dependent effect of PPI use and gastric cancer risk (< 1 year: OR: 2.56, 95% CI: 1.41-4.64, I² = 98%; 1-3 years: OR: 1.47, 95% CI: 1.26-1.71, I² = 41%; > 3 years: OR: 1.58, 95% CI: 1.16-2.14, I² = 74%).

CONCLUSIONS

PPIs were significantly associated with an increased risk of gastric cancer. However, this association does not confirm causation. Several well-design studies are needed to confirm the findings in the future.

Using proton pump inhibitors increases the risk of hepato-biliary-pancreatic cancer. A systematic review and meta-analysis

Background: More and more studies are focusing on the adverse effects and damage caused by PPI abuse, we carried out a systematic review and meta-analysis for assessing whether the proton pump inhibitor (PPI) leads to hepato-biliary-pancreatic cancer.

Methods: PubMed, EMBASE and Web of Science were searched until 1 July 2022, 25 studies (17 case-control and 8 cohort studies; 2741853 individuals) included in this study. Pooled Odd Ratios (ORs) were used for random effect models. Sensitivity analysis and dose-response analysis, subgroup analysis were all conducted.

Results: The aggregate OR of the meta-analysis was 1.69 (95% confidence interval (CI): 1.42–2.01, p = 0.01) and heterogeneity (I² = 98.9%, p < 0.001) was substantial. According to stratified subgroup analyses, the incidence of hepato-biliary-pancreatic cancer was associated, expect for study design, study quality and region. Risk of hepato-biliary-pancreatic cancer is highest when people is treated with normal doses of PPI. The risks decrease and become insignificant when the cumulative defined daily dose (cDDD) increases.

Conclusion: The use of PPI may be associated with an increased risk of hepato-biliary-pancreatic cancer. Hence, caution is needed when using PPIs among patients with a high risk of hepato-biliary-pancreatic cancer.

Risk factors for the occurrence of ampullary tumors: A case-control study

Background

The incidence of ampullary tumors is increasing but data on association with an increased exposure to certain risk factors are scanty.

Objective

To investigate risk and protective factors associated with the occurrence of ampullary tumors and whether these factors differ between ampullary tumors of the intestinal and pancreatobiliary subtypes or between adenomas and carcinomas.

Methods

The association between a large set of exposome features and ampullary tumors occurrence was investigated in a bi‐centric case‐control study after ethic committee approval and power calculation.

Results

In 223 histologically confirmed patients and 446 controls, previous cholecystectomy (odd ratio [OR] = 2.07; 95% confidence interval [CI] = 1.34–3.20) and proton pump inhibitors use (OR = 1.66; 95% CI = 1.16–2.37) were associated with increased risk of ampullary tumors, aspirin use (OR = 0.57; 95% CI = 0.36–0.90) and light alcohol intake (OR = 0.54; 95% CI = 0.38–0.76) with reduced risk. A previous cholecystectomy was also associated with tumors of intestinal subtype and with both adenomas and carcinomas, and proton pump inhibitors use with adenomas only. Smoking, body mass index, family history of cancers, previous ulcer, diabetes and use of statins, insulin and metformin were not significant factors.

Conclusion

This is the first case‐control study specifically highlighting factors associated with the occurrence of ampullary tumors. We report factors that are novel and plausible, in keeping with mechanisms described for other gastrointestinal tumors and with potential clinical relevance.

Association Between DPP-4 Inhibitors and Events of Colorectal and Liver Cancers in Patients With Diabetes Receiving Second-Line Agents: A Nested Case-Control Study

Objective

Plasma dipeptidyl peptidase-4 (DPP4) levels were significantly lower in patients with colorectal and liver cancers, and animal studies also showed DPP4 inhibitors (DPP4is) have procarcinogenic effects in colorectal cancer. Until now, whether DPP4is therapy affects the progression of liver cancer and colorectal cancer in patients with T2DM has not been well investigated. We investigated the association between cumulative defined daily dose (cDDD) of DPP4is exposure and risks of liver and colorectal cancers in patients with type 2 diabetes.

Materials and Methods

We identified 268,520 patients with diabetes receiving DPP4is as second-line agents between March 1, 2009, and December 31, 2013, from Taiwan’s National Health Insurance Research Database, Taiwan Cancer Registry, and National Death Registry of Taiwan. The amount of DPP4is were divided into three groups (low, medium, and high) based on the interquartile range of the cDDD of the DPP4is.

Results

The data showed that the low cDDD of DPP-4is was associated with a reducing risk of colorectal cancer [adjusted odds ratio (OR), 0.49; 95% CI, 0.32–0.75; P=0.001]. However, the high cDDD of DPP-4is was associated with an increasing risk of colorectal cancer (adjusted OR, 1.86; 95% CI, 1.32–2.61; P&lt;0.001). No association between DPP4is use and liver cancer risk was observed.

Conclusions

This nested case study revealed a J-shaped association between the cDDD of DPP-4is and colorectal cancer risk, but not liver cancer risk. Therefore, the effects of long-term DPP4is use on colorectal cancer risk warrant further study.

Association between proton-pump inhibitors and the risk of gastric cancer: a systematic review with meta-analysis

INTRODUCTION

The use of proton-pump inhibitors (PPI) may be associated with an increased risk of gastric cancer (GC).

OBJECTIVE

To review and meta-analyse available literature investigating the association between PPI use and GC risk.

METHODS

Two independent reviewers systematically searched Ovid MEDLINE, EMBASE, and Cochrane Library (inception to July 2020) for case-control and cohort studies assessing the association between PPI use and GC according to a predefined protocol in PROSPERO (CRD42018102536). Reviewers independently assessed study quality, extracted data, and meta-analysed available and newly calculated odds ratios (ORs) using a random-effects model, and stratified for GC site (cardia versus non-cardia) and PPI duration (<1 year, 1-3 years, >3 years).

RESULTS

We screened 2,396 records and included five retrospective cohort and eight case-control studies comprising 1,662,881 individuals in our meta-analysis. In random-effect models, we found an increased GC risk in PPI users [OR: 1.94, 95% confidence interval (95% CI): 1.47-2.56] with high statistical heterogeneity (I ² = 82%) and overall moderate risk of bias. Stratified analyses indicated a significant risk increase in non-cardia (OR: 2.20, 95% CI: 1.44-3.36, I ² = 77%) with a similar non-significant trend in cardia regions (OR: 1.77, 95% CI: 0.72-4.36, I ² = 66%). There was no GC increase with longer durations of PPI exposure (<1 year: OR: 2.29, 95% CI: 2.13-2.47, I ² = 0%; 1-3 years: OR: 1.46, 95% CI: 0.53-4.01, I ² = 35%; >3 years: OR: 2.08, 95% CI: 0.56-7.77, I ² = 61%).

CONCLUSION

We found a twofold increased GC risk among PPI users, but this association does not confirm causation and studies are highly heterogeneous. PPI should only be prescribed when strictly indicated.

Association between proton pump inhibitors after percutaneous coronary intervention and risk of gastric cancer

BACKGROUND

Previous studies showing an association between chronic use of proton pump inhibitor (PPI) and gastric cancer are limited by confounding by indication. This relationship has not been studied in patients receiving PPI for prophylaxis, such as those undergoing percutaneous coronary intervention (PCI).

METHOD

This was a retrospective cohort study including 14 hospitals under the Hospital Authority of Hong Kong between 1 January 2004 and 31 December 2017. Participants were patients who underwent first-ever PCI, were not on PPI prescription within 30 days before admission for PCI, had no known malignancy and survived for 365 days after PCI. Propensity score matching was used to balance baseline characteristics and other prescription patterns. The primary outcome was diagnosis of gastric cancer made >365 days after PCI as a time-to-first-event analysis. The secondary outcome was death from gastric cancer.

RESULTS

Among the 13 476 patients (6738 pairs) matched by propensity score, gastric cancer developed in 17 (0.25%) PPI users and 7 (0.10%) PPI non-users after a median follow-up of 7.1 years. PPI users had a higher risk of gastric cancer (HR 3.55; 95% CI 1.46 to 8.66, p=0.005) and death from gastric cancer (HR 4.18; 95% CI 1.09 to 16.08, p=0.037), compared with non-users. The association was duration-dependent and patients who took PPI for ≥365 days were at increased risk.

CONCLUSIONS

Chronic use of PPI was significantly associated with increased risk of gastric cancer and death from gastric cancer in patients for whom it was prescribed as prophylaxis. Physicians should judiciously assess the relevant risks and benefits of chronic PPI use before prescription.

When does proton pump inhibitor treatment become long term? A scoping review

Objective

Proton pump inhibitor (PPI) use has risen substantially, primarily driven by ongoing use over months to years. However, there is no consensus on how to define long-term PPI use. Our objectives were to review and compare definitions of long-term PPI use in existing literature and describe the rationale for each definition. Moreover, we aimed to suggest generally applicable definitions for research and clinical use.

Design

The databases PubMed and Cochrane Library were searched for publications concerning long-term use of PPIs and ClinicalTrials.gov was searched for registered studies. Two reviewers independently screened the titles, abstracts, and full texts in two series and subsequently extracted data.

Results

A total of 742 studies were identified, and 59 met the eligibility criteria. In addition, two ongoing studies were identified. The definition of long-term PPI use varied from >2 weeks to >7 years. The most common definition was ≥1 year or ≥6 months. A total of 12/61 (20%) of the studies rationalised their definition.

Conclusion

The definitions of long-term PPI treatment varied substantially between studies and were seldom rationalised.

In a clinical context, use of PPI for more than 8 weeks could be a reasonable definition of long-term use in patients with reflux symptoms and more than 4 weeks in patients with dyspepsia or peptic ulcer. For research purposes, 6 months could be a possible definition in pharmacoepidemiological studies, whereas studies of adverse effects may require a tailored definition depending on the necessary exposure time. We recommend to always rationalise the choice of definition.

A Population-Based Cohort Study Examining the Long-term Risk of Repeated Surgery in Non-Helicobacter pylori-Infected PPU Patients Who Underwent Simple Closure

OBJECTIVES

The management of perforated peptic ulcer (PPU) has shifted from vagotomy/drainage to simple closure, followed by postoperative proton pump inhibitors (PPIs) and Helicobacter pylori (HP) eradication. Few studies have focused on the long-term impacts of this trend shift. We hypothesize that simple closure with PPIs is sufficient and does not carry an elevated rate of repeated surgery in non-HP-infected PPU patients.

METHODS

Hospitalized PPU patients who underwent simple closure or truncal vagotomy/pyloroplasty (TVP) in the National Health Insurance Research Database (NHIRD) from 2000 to 2008 were collected. The index date was defined as the date of ulcer admission. Patients who underwent other ulcer surgeries (e.g., gastrectomy, highly or selective vagotomy), who had a history of HP infection, or who were < 18 or > 100 years old were excluded. Additionally, the distributions of postoperative nonsteroidal anti-inflammatory drug (NSAID) and PPI use were calculated using the Longitudinal Health Insurance Database (LHID).

RESULTS

After exclusion, a total of 66,413 patients were enrolled. There were 7232 (10.9%) patients who underwent TVP and 59,181 (89.1%) patients who underwent simple closure. The incidences of repeated ulcer-associated surgery were 5.10 and 23.05 versus 5.11 and 15.77 per 1000 person-years in the TVP cohort vs. the simple closure cohort before and after propensity score matching, respectively. When adjusted for age, sex, comorbidity, and Charlson comorbidity index score, the TVP cohort had a 68% (HR) and 66% (sHR) decreased risk compared with the simple closure cohort before propensity score matching, with a 67% decreased risk after propensity score matching in Cox proportional subdistribution hazard analysis and a 66% decreased risk in Fine-Gray proportional subdistribution hazard analysis. The LHID analysis showed a lower rate of postoperative NSAID use and a higher rate of postoperative PPI use in simple closure patients.

CONCLUSION

Our findings suggest that in the Asian population, simple closure increases the risk of repeated ulcer-associated surgery in non-HP-infected PPU patients compared with TVP patients. However, further studies are warranted.

Proton pump inhibitors and odds of cholangiocarcinoma: A retrospective case-control study

BACKGROUND & AIMS

Proton pump inhibitors (PPIs) have been reported to be associated with cholangitis and might possibly be carcinogenic. However, few studies have been conducted to investigate the association of PPIs with cholangiocarcinoma (CCA). Thus, a hospital-based case-control study was carried out in China to explore the association between PPIs and CCA.

METHODS

In this study, 1468 CCA cases (826 intrahepatic cholangiocarcinoma (ICC) and 642 extrahepatic cholangiocarcinoma (ECC)) were included, which were observed at Beijing Friendship Hospital, from February 2002 to October 2018. We retrospectively extracted PPI use and other possible risk factors from clinical records, followed by an investigation of the relationship with CCA via calculation of odds ratios (ORs), adjusted odds ratios (AORs), and 95% confidence intervals (CIs) using logistic regression analysis.

RESULTS

PPIs were used by 135 (9.2%) CCA cases and 173 (5.9%) controls. We found that PPI use was associated with a 1.61-fold elevated CCA odds (P < .001) (AOR = 1.61, 95% CI = 1.28-2.05; P < .001). After stratification by CCA subtypes, the AORs of PPIs were consistent for both CCA subtypes, with ORs of 1.36 (AOR = 1.36, 95% CI = 1.02-1.83; P = .003) and 1.95 (AOR = 1.95, 95% CI = 1.46-2.62; P < .001) for ICC and ECC respectively. Our results also showed that PPI use was slightly linked to the odds of CCA in a dose-dependent manner.

CONCLUSION

PPI use was correlated with a significant 61% increased odds of CCA, particularly in the ECC. However, the retrospective design and observational nature cannot establish causation. Larger scale, multi-centre prospective studies are required for further validation.

The association between acid-suppressive agent use and the risk of cancer: a systematic review and meta-analysis

BACKGROUND

Acid-suppressive agents (ASAs) may be associated with cancer; previous studies reported that the risk of cancer with acid suppressants has differed depending on the site of cancer. Here, we conducted a systematic review and meta-analysis of the association between ASA use and the type of cancer risk.

METHODS

MEDLINE, EMBASE, and Cochrane library databases were searched for publications up to the end of September 2019 for MeSH terms and text words related to cancer and ASAs. Studies on the association between ASAs and cancer risk, which included a control group and reported the relative risk of cancer, were included. The inverse-variance random effect model was used to estimate the pooled relative risk (RR) and 95% confidence interval (CI), and subgroup analysis for type of acid suppressants, drug uptake duration, and cumulative doses was performed. Heterogeneity was assessed using the I² test and Q statistic.

RESULTS

Thirty-nine cohort and case-control studies were included. ASA use was found to be significantly associated with a 46% higher risk of gastric cancer (RR, 1.46; 95% CI, 1.18-1.80) and a 53% higher risk of liver cancer (RR, 1.53; 95% CI, 1.31-1.78) compared with nonuse; however, there was no significant association for esophageal, colorectal, pancreatic, lung, breast, prostate, and kidney cancer; melanoma; and lymphoma.

CONCLUSIONS

ASAs were significantly associated with an increased risk of gastric and liver cancer; therefore, special attention of ASA use considering the potential risk of gastric and liver cancer is needed.

Long-term proton pump inhibitor usage and the association with pancreatic cancer in Sweden

BACKGROUND

The long-term safety of proton pump inhibitors (PPIs) is increasingly questioned. The aim of our study was to assess the risk of pancreatic cancer among long-term PPI users in Sweden.

METHODS

This population-based nationwide Swedish cohort study including 796,492 adult long-term PPI users has been used to calculate the standardized incidence rate ratios (SIRs) and 95% confidence intervals (CI) for pancreatic cancer, stratifying by indications of use, age, sex, and duration of use. The risk among all 20,210 long-term H2-receptor antagonist users was assessed as comparison.

RESULTS

Pancreatic cancer was found in 1733 long-term PPI users, and 25 H2-receptor antagonist users. For PPI users, the risk of pancreatic cancer was increased overall (SIRs = 2.22; 95% CI 2.12-2.32) and in all subgroup analyses, with the highest risk among PPI-users younger than 40 years (SIR = 8.90, 95% CI 4.26-16.37), and among individuals with a history of Helicobacter pylori (SIR = 2.99, 95% CI 2.54-3.49). After the first year after enrolment (during which PPI use may be because of early symptoms of pancreatic cancer), the risk remained increased over time, with SIR = 1.57 (95% CI 1.38-1.76) after 5 years. No associations were found for H2-receptor antagonists (SIR = 1.02, 95% CI 0.66-1.51).

CONCLUSIONS

This large study showed an increased risk of pancreatic cancer in long-term users of PPIs in Sweden, in particular among the youngest users.

Exposure to proton pump inhibitors and risk of pancreatic cancer: a meta-analysis

Objectives: To estimate the pancreatic cancer risk among subjects exposed versus not exposed to proton pump inhibitors.Methods: The authors searched PubMed, EMBASE, Scopus, Cochrane Library, and clinicaltrials.gov to identify relevant studies. The authors quantified pancreatic cancer risk among subjects exposed versus not exposed to PPIs, expressed as the pooled (adjusted) odds ratio (OR/aOR) and 95% confidence interval (95%CI) in overall and sensitivity analyses.Results: One randomized trial, two cohort, four case-control, and five nested case-control studies with 700,178 subjects (73,985 cases; 626,193 controls) were retained. PPI exposure was associated with pancreatic cancer risk (OR = 1.75, 95%CI = 1.12-2.72, I2 = 99%); confirmed in sensitivity analyses for high-quality studies, observational studies, case-control studies, studies with pancreatic cancer as the primary outcome, and in sensitivity analyses for diabetes and obesity but not for pancreatitis and smoking. This association was independent of the duration and Defined Daily Dose of PPI exposure. Rabeprazole had a singular significant association with pancreatic cancer (OR = 5.40, 95%CI = 1.98-14.703, I2 = 87.9%).Conclusion: The class of PPIs is associated with a 1.75-fold increase in pancreatic cancer risk, confirmed in sensitivity analyses.

Long-term Proton Pump Inhibitor Administration Caused Physiological and Microbiota Changes in Rats

Proton pump inhibitors (PPIs) are used for the long-term treatment of gastroesophageal disorders and the non-prescription medicines for acid reflux. However, there is growing concerns about PPI misuse, overuse and abuse. This study aimed to develop an animal model to examine the effects of long-term use of PPI in vivo. Twenty one Wistar rats were given omeprazole orally or intravenously for 30 days, and caerulein as a positive control. After euthanization, the serum and stool were collected to perform MS-based quantitative analysis of metabolites. We carried out 16S-based profiling of fecal microbiota, assessed the expression of bile acid metabolism regulators and examined the immunopathological characteristics of bile ducts. After long-term PPI exposure, the fecal microbial profile was altered and showed similarity to those observed in high-fat diet studies. The concentrations of several metabolites were also changed in various specimens. Surprisingly, morphological changes were observed in the bile duct, including ductal epithelial proliferation, micropapillary growth of biliary epithelium, focal bile duct stricture formation and bile duct obstruction. These are characteristics of precancerous lesions of bile duct. FXR and RXRα expressions were significantly reduced, which were similar to that observed in cholangiocarcinoma in TCGA and Oncomine databases. We established a novel animal model to examine the effects of long-term use of omeprazole. The gut microbes and metabolic change are consequences of long-term PPI exposure. And the results showed the environment in vivo tends to a high-fat diet. More importantly, we observed biliary epithelial hyperplasia, which is an indicator of a high-fat diet.

Proton Pump Inhibitors and Risk of Hepatocellular Carcinoma in Patients With Chronic Hepatitis B or C

Researchers have hypothesized that the long-term use of proton pump inhibitors (PPIs) can increase the risk of developing cancer. However, the association between PPI use and hepatocellular carcinoma (HCC) risk is unclear. Using data from the Taiwan National Health Insurance Research Database for the period between 2003 and 2013, we identified 35,356 patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections. One-to-one propensity score matching by gender, age, cohort entry year, comorbidity, and medication resulted in the inclusion of 7,492 pairs of patients (PPI users and non-PPI users) for analyses. We performed multivariate and stratified analysis using the Kaplan-Meier method and Cox proportional hazards models in order to estimate the association between PPI use and the risk of developing HCC. In the HBV cohort, 237 patients developed HCC during a median follow-up of 53 months. However, PPI use was not associated with an increased risk of developing HCC (adjusted hazard ratio [aHR], 1.25; 95% confidence interval [CI], 0.90-1.73; P = 0.18). In the HCV cohort, 211 patients developed HCC; but again, PPI use was not associated with an increase in the risk of developing HCC (aHR, 1.19; 95% CI, 0.88-1.61; P = 0.25). We observed no relationship between a dose-dependent effect of PPI use and HCC risk. Subgroup analysis also confirmed that PPI use was not correlated to an increased HCC risk. Conclusion: Based on a retrospective population-based cohort study throughout Taiwan, where the prescription of PPI is tightly regulated, PPI use is not associated with the risk of developing HCC among patients with chronic HBV or HCV infections.

Negative Association of Proton Pump Inhibitors With Subsequent Development of Breast Cancer: A Nationwide Population-Based Study

Although current evidence suggests potential antitumor activity of proton pump inhibitors (PPIs), there is no population-based evidence of an association between PPI use and subsequent breast cancer risks. We used an observational case-control study to examine the association between prior PPI use and breast cancer occurrence. Additional analysis examined dose-response and age-stratified associations of PPIs with breast cancer. This study used data from the Taiwan National Health Insurance Research Dataset. A total of 64,234 women diagnosed with breast cancer between 2004 and in 2013 were selected as cases. Controls were 64,234 women without cancer who were selected by matching them with cases on the basis of sociodemographic characteristics and widely prevalent comorbidities. Each study subject's claims data were tracked back for 5 years to determine precancer prescriptions of PPIs. Logistic regression modeling was used for the analysis. A total of 11,871 (9.24%) women had used PPIs within the prior 5 years, 8.06% and 10.42% among cases and controls, respectively. Breast cancer patients were 25% less likely to have had prior PPI exposure after adjustment for comorbidities that predispose to PPI exposure (95%CI 0.72-0.78) in the risk of breast cancer occurrence. A dose-response effect was also detected, with the highest effect, 35% lower PPI odds (95%CI 0.61-0.70) among patients in the highest exposure category. Our findings may suggest that women at a higher-than-average risk of breast cancer may benefit from PPI prescriptions if they have medical conditions that could benefit from PPIs.

Proton Pump Inhibitor Use is Associated With Risk of Pancreatic Cancer: A Nested Case-Control Study

Purpose:

To investigate the use of proton pump inhibitors (PPIs) and the risk of pancreatic cancer.

Methods:

A nested case–control analysis was conducted. Patients with pancreas cancer were matched with controls by propensity score. Univariate and multivariate logistic regression models were used to determine whether PPIs use affected the risk of pancreas cancer. Dose effect was analyzed based on the cumulative defined daily dose (DDD), which was calculated using the total supply of PPIs to individual patients in terms of days and quantity.

Results:

A total of 1087 patients with pancreas cancer were matched with 1087 control patients from the database. The overall adjusted odds ratio (OR) of PPI use associated with pancreas cancer was 1.69 (95% confidence interval [CI], 1.44-2.05). Dose analysis by cumulative DDD, based on all types of PPI combined, revealed a lower adjusted OR of 0.92 (95% CI, 0.64-1.33) for those on <30 cumulative DDD compared with those on ≥150 cumulative DDD, whose adjusted OR was 2.19 (95% CI, 1.68-2.85). Compared with PPI nonusers, the risks of pancreas cancer were: OR 0.89 (95% CI, 0.62-1.27) for patients using PPI <30 days and 2.22 (95% CI, 1.68-2.94) for ≥150 days.

Conclusions:

Risk of pancreas cancer was associated with PPI use in patients with peptic ulcer diseases or gastroesophageal reflux disease.

Association between proton pump inhibitors and the risk of hepatocellular carcinoma

BACKGROUND

Proton pump inhibitor (PPI) use has been reported to be associated with liver damage and might possibly be carcinogenic.

AIMS

We examined whether long-term PPI use increases the risk of hepatocellular carcinoma (HCC) in patients without viral hepatitis B or C.

METHODS

We conducted a nested case-control study in a cohort of patients without viral hepatitis in Taiwan from 2000 to 2013. In total, 29 473 HCC cases and 294 508 matched controls were included. Moreover, we identified prescriptions for PPI and durations between the PPI index date and cancer diagnosis date (or the corresponding date in controls).

RESULTS

The adjusted odds ratio (AOR) for HCC associated with PPI use was 2.86 (95% confidence interval [CI], 2.69-3.04). Considering the use of PPIs determined according to cumulative defined daily dose (cDDD) subgroups, a dose-response effect was observed in patients exposed to 29-180, 181-240, 241-300, and 300+ cDDDs of PPIs. The AORs were 2.74 (95% CI, 2.57-2.93), 2.98 (95% CI, 2.50-3.56), 3.23 (95% CI, 2.59-4.02), and 3.43 (95% CI, 2.94-4.00) in the 29-180, 181-240, 241-300, and 300+ cDDD groups, respectively, compared with the 0-28 cDDD group. A sensitivity analysis revealed a consistent association between PPI use and the risk of HCC in subpopulations stratified by risk factors associated with HCC.

CONCLUSIONS

This observational study demonstrated that PPIs might increase the risk of HCC.

Use of proton pump inhibitors and risk of pancreatic cancer

PURPOSE

Preclinical studies have suggested that proton pump inhibitors (PPIs) may increase pancreatic cancer risk; however, epidemiological studies are few, with conflicting results. This spurred us to evaluate whether PPI use is associated with an increased risk of pancreatic cancer in a large population-based study.

METHODS

We conducted a nationwide case-control study using data from Danish demographic and health care registries. All patients with a first cancer diagnosis of pancreatic cancer between 2000 and 2015 were identified from the Danish Cancer Registry and age-matched, sex-matched, and calendar-matched 1:20 to population controls using risk set sampling. Conditional logistic regression was applied to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for pancreatic cancer associated with PPI use, adjusting for potential confounders. Secondary analyses examined dose-response patterns and associations with individual PPIs as well as with histamine-2-receptor antagonists.

RESULTS

Ever use of PPIs occurred among 27.8% of 6921 pancreatic cancer cases and 25.4% of 34 695 matched controls, yielding a neutral adjusted OR of 1.04 (95% CI 0.97-1.11). Odds ratios were also close to unity in analyses of high use of PPIs (≥1000 DDDs; OR, 0.92 95% CI 0.80-1.07). There was no evidence of a dose-response relationship, with ORs close to unity across categories, including for those with the highest cumulative use (>2000 DDDs; OR, 1.03 95% CI 0.84-1.26). Analyses of subgroups as well as individual types of PPI and of histamine-2-receptor antagonists use also returned neutral associations.

CONCLUSIONS

In this large nationwide case-control study, PPI use was not associated with an increased risk of pancreatic cancer.

Association Between Cholangiocarcinoma and Proton Pump Inhibitors Use: A Nested Case-Control Study

Background: The present study aimed to examine the odds of cholangiocarcinoma (CCA) in patients with proton pump inhibitors (PPIs) use. Methods: A nested case-control study design was employed using data obtained from Taiwan's National Health Insurance Research Database. In total, 2,293 patients with confirmed diagnosis of CCA were identified and served as the CCA group. The CCA patients were propensity score-matched with 2,293 subjects without CCA who served as the control group. The cumulative defined daily dose (DDD) of PPIs was calculated based on the total supply in days and quantity of individual PPIs. Univariable and multivariate logistic regression models were used to determine the odds of CCA, and calculated odds ratios (ORs) and 95% confidence intervals (CI) were used to assess PPIs use and odds of CCA. Results: The overall adjusted OR of PPIs use-associated CCA was 2.58 (95% CI 2.27, 2.93). The adjusted OR of CCA by cumulative DDD dose of PPIs and CCA was analyzed and revealed those odds of CCA are associated with all types of PPIs. Conclusions: There were odds of intrahepatic and extrahepatic CCA among PPIs users. All PPIs use was associated with odds of CCA. Analyses of larger numbers of cases are needed to confirm these findings.

Interactive role of diabetes mellitus and female sex in the risk of cholangiocarcinoma: A population-based nested case-control study

Diabetes mellitus (DM) has been associated with an increased risk of extrahepatic cholangiocarcinoma (ECC) and intrahepatic cholangiocarcinoma (ICC). However, the role of DM in a population with a lower incidence of ECC remains unclear. We investigated the role of DM and other risk factors for ECC and ICC by conducting a population-based, nested, case–control study in Taiwan, a region with a lower incidence but a higher proportion of ICC. We identified patients who received a diagnosis of cholangiocarcinoma (CC) from the Taiwan Cancer Registry between 2003 and 2009. A total of 6,093 CC cases (ICC: 4,695; ECC: 1,396) and 60,906 matched controls were included. Compared with the controls, the patients with ICC and ECC were more likely to have DM, with an adjusted OR of 1.22 [95% confidence interval (CI): 1.07–1.39] and 1.48 (95% CI: 1.18–1.85), respectively. DM was associated with an increased risk of CC in the women and patients without a history of biliary tract diseases. Moreover, compared with the controls, DM was not associated with an increased risk of ECC in the patients who received cholecystectomy. These findings strongly support the positive association between DM and the increased risk of both ICC and ECC; however, this association was not observed in the patients who received cholecystectomy.

A case of adenocarcinoma developed in the small intestine with chronic strongyloidiasis

We experienced a case of intestinal strongyloidiasis complicated by jejunal carcinoma. A Japanese male in his 50s, who has a 7-year medical history of duodenal ulcers, complained of loss of appetite, nausea, vomiting and diarrhea. Computed tomography and gastroduodenal endoscopic examination revealed a stenosis of the duodenum. To remove the stenosis, gastric bypass surgery was performed. The pathological diagnosis of the resected jejunum was strongyloidiasis and well-differentiated adenocarcinoma with subserosal invasion and vascular infiltration. After administration of Ivermectin, Strongyloides stercoralis was not found in any biopsies or in the specimens of the intestine, which were resected due to cancer recurrence 2 years later. There are three possibilities for the reason of coexistence of S. stercoralis and adenocarcinoma: S. stercoralis caused the adenocarcinoma, S. stercoralis moved to the carcinoma, or just coincidence. Although it is difficult to prove a causal relationship between S. stercoralis and adenocarcinoma, this is the first report of adenocarcinoma developed in the jejunum with chronic strongyloidiasis. The number of nematode infections, including strongyloidiasis, is decreasing in Japan, although not worldwide. Therefore, it should be considered in patients with prolonged intestinal ulcers.

Adverse reactions and rational use of proton pump inhibitors

Proton pump inhibitors (PPIs) are a class of important drugs for treating acid related diseases, such as gastroesophageal reflux diseases (GERD), peptic ulcer, Zollinger-Ellison syndrome, and upper gastrointestinal bleeding. When combined with other drugs, PPIs can be used for the eradication of Helicobacter pylori. Short-term use of PPIs can cause allergic reactions, adverse reactions of the hematologic system, the digestive system and the nervous system and so on. Long-term use of PPIs can cause a series of new safety issues, such as increased risk of infection, vitamin B₁₂ deficiency caused by the lack of nutrients, fractures, hypomagnesemia, occurrence or development of atrophic gastritis, interstitial nephritis, microscopic colitis, increased risk of serious skin allergy and so on. However, inappropriate use and off-label use of PPIs, and even abuse of PPIs are very common worldwide. Therefore, clinical rational use of PPIs should be emphasized among the relevant national administration departments, clinicians and pharmacists.