Antireflux Surgery Versus Antireflux Medication and Risk of Esophageal Adenocarcinoma in Patients With Barrett's Esophagus.

BACKGROUND & AIMS: Antireflux treatment is recommended to reduce esophageal adenocarcinoma in patients with Barrett's esophagus. Antireflux surgery (fundoplication) counteracts gastroesophageal reflux of all types of carcinogenic gastric content and reduces esophageal acid exposure to a greater extent than antireflux medication (eg, proton pump inhibitors). We examined the hypothesis that antireflux surgery prevents esophageal adenocarcinoma to a larger degree than antireflux medication in patients with Barrett's esophagus. METHODS: This multinational and population-based cohort study included all patients with a diagnosis of Barrett's esophagus in any of the national patient registries in Denmark (2012-2020), Finland (1987-1996 and 2010-2020), Norway (2008-2020), or Sweden (2006-2020). Patients who underwent antireflux surgery were compared with nonoperated patients using antireflux medication. The risk of esophageal adenocarcinoma was calculated using multivariable Cox regression, providing hazard ratios (HRs) and 95% CIs adjusted for age, sex, country, calendar year, and comorbidity. RESULTS: The cohort consisted of 33,939 patients with Barrett's esophagus. Of these, 542 (1.6%) had undergone antireflux surgery. During up to 32 years of follow-up, the overall HR was not decreased in patients having undergone antireflux surgery compared with nonoperated patients using antireflux medication, but rather increased (adjusted HR, 1.9; 95% CI, 1.1-3.5). In addition, HRs did not decrease with longer follow-up, but instead increased for each follow-up category, from 1.8 (95% CI, 0.6-5.0) within 1-4 years of follow-up to 4.4 (95% CI, 1.4-13.5) after 10-32 years of follow-up. CONCLUSIONS: Patients with Barrett's esophagus who undergo antireflux surgery do not seem to have a lower risk of esophageal adenocarcinoma than those using antireflux medication.

Risk of Esophageal Adenocarcinoma After Helicobacter pylori Eradication Treatment in a Population-Based Multinational Cohort Study.

BACKGROUND & AIMS: Helicobacter pylori infection is associated with a decreased risk of esophageal adenocarcinoma, and the decreasing prevalence of such infection might contribute to the increasing incidence of this tumor. We examined the hypothesis that eradication treatment of H pylori increases the risk of esophageal adenocarcinoma. METHODS: This population-based multinational cohort, entitled "Nordic Helicobacter Pylori Eradication Project (NordHePEP)," included all adults (≥18 years) receiving H pylori eradication treatment from 1995-2018 in any of the 5 Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden) with follow-up throughout 2019. Data came from national registers. We calculated standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) by dividing the cancer incidence in the exposed cohort by that of the entire Nordic background populations of the corresponding age, sex, calendar period, and country. Analyses were stratified by factors associated with esophageal adenocarcinoma (ie, education, comorbidity, gastroesophageal reflux, and certain medications). RESULTS: Among 661,987 participants who contributed 5,495,552 person-years after eradication treatment (median follow-up, 7.8 years; range, 1-24 years), 550 cases of esophageal adenocarcinoma developed. The overall SIR of esophageal adenocarcinoma was not increased (SIR = 0.89; 95% CI, 0.82-0.97). The SIR did not increase over time after eradication treatment, but rather decreased and was 0.73 (95% CI, 0.61-0.86) at 11-24 years after treatment. There were no major differences in the stratified analyses. The overall SIR of esophageal squamous cell carcinoma, calculated for comparison, showed no association (SIR = 0.99; 95% CI, 0.89-1.11). CONCLUSIONS: This absence on an increased risk of esophageal adenocarcinoma after eradication treatment of H pylori suggests eradication is safe from a cancer perspective.

Magnitude and Time-Trends of Post-Endoscopy Esophageal Adenocarcinoma and Post-Endoscopy Esophageal Neoplasia in a Population-Based Cohort Study: The Nordic Barrett's Esophagus Study.

BACKGROUND & AIMS: Post-endoscopy esophageal adenocarcinoma (PEEC) and post-endoscopy esophageal neoplasia (PEEN) undermine early cancer detection in Barrett's esophagus (BE). We aimed to assess the magnitude and conduct time-trend analysis of PEEC and PEEN among patients with newly diagnosed BE. METHODS: This population-based cohort study was conducted in Denmark, Finland, and Sweden between 2006 and 2020 and included 20,588 patients with newly diagnosed BE. PEEC and PEEN were defined as esophageal adenocarcinoma (EAC) or high-grade dysplasia (HGD)/EAC, respectively, diagnosed 30-365 days from BE diagnosis (index endoscopy). HGD/EAC diagnosed from 0-29 days and HGD/EAC diagnosed >365 days from BE diagnosis (incident HGD/EAC) were assessed. Patients were followed up until HGD/EAC, death, or end of study period. Incidence rates (IR) per 100,000 person-years with 95% confidence interval (95% CI) were calculated using Poisson regression. RESULTS: Among 293 patients diagnosed with EAC, 69 (23.5%) were categorized as PEEC, 43 (14.7%) as index EAC, and 181 (61.8%) as incident EAC. The IRs/100,000 person-years for PEEC and incident EAC were 392 (95% CI, 309-496), and 208 (95% CI, 180-241), respectively. Among 279 patients diagnosed with HGD/EAC (Sweden only), 17.2% were categorized as PEEN, 14.6% as index HGD/EAC, and 68.1% as incident HGD/EAC. IRs/100,000 person-years for PEEN, and incident HGD/EAC were 421 (95% CI, 317-558), and 285 (95% CI, 247-328), respectively. Sensitivity analyses that varied time interval for occurrence of PEEC/PEEN demonstrated similar results. A time-trend analysis for IRs demonstrated rising incidence rates of PEEC/PEEN. CONCLUSIONS: Almost a quarter of all EACs are detected within a year after an ostensibly negative upper endoscopy in patients with newly diagnosed BE. Interventions to improve detection may reduce PEEC/PEEN rates.

Decreased Risk of Esophageal Adenocarcinoma After Gastric Bypass Surgery in a Cohort Study From 3 Nordic Countries.

OBJECTIVE: The objective of this study was to test the hypothesis that bariatric surgery decreases the risk of esophageal and cardia adenocarcinoma. BACKGROUND: Obesity is strongly associated with esophageal adenocarcinoma and moderately with cardia adenocarcinoma, but whether weight loss prevents these tumors is unknown. METHODS: This population-based cohort study included patients with an obesity diagnosis in Sweden, Finland, or Denmark. Participants were divided into a bariatric surgery group and a nonoperated group. The incidence of esophageal and cardia adenocarcinoma (ECA) was first compared with the corresponding background population by calculating standardized incidence ratios (SIR) with 95% CIs. Second, the bariatric surgery group and the nonoperated group were compared using multivariable Cox regression, providing hazard ratios (HR) with 95% CI, adjusted for sex, age, comorbidity, calendar year, and country. RESULTS: Among 748,932 participants with an obesity diagnosis, 91,731 underwent bariatric surgery, predominantly gastric bypass (n=70,176; 76.5%). The SIRs of ECA decreased over time after gastric bypass, from SIR=2.2 (95% CI, 0.9-4.3) after 2 to 5 years to SIR=0.6 (95% CI, <0.1-3.6) after 10 to 40 years. Gastric bypass patients were also at a decreased risk of ECA compared with nonoperated patients with obesity [adjusted HR=0.6, 95% CI, 0.4-1.0 (0.98)], with decreasing point estimates over time. Gastric bypass was followed by a strongly decreased adjusted risk of esophageal adenocarcinoma (HR=0.3, 95% CI, 0.1-0.8) but not of cardia adenocarcinoma (HR=0.9, 95% CI, 0.5-1.6), when analyzed separately. There were no consistent associations between other bariatric procedures (mainly gastroplasty, gastric banding, sleeve gastrectomy, and biliopancreatic diversion) and ECA. CONCLUSIONS: Gastric bypass surgery may counteract the development of esophageal adenocarcinoma in morbidly obese individuals.

Incidence and Mortality in Upper Gastrointestinal Cancer After Negative Endoscopy for Gastroesophageal Reflux Disease.

BACKGROUND AND AIMS: Gastroesophageal reflux disease (GERD) is associated with an increased risk of cancer of the upper gastrointestinal tract. This study aimed to assess whether and to what extent a negative upper endoscopy in patients with GERD is associated with decreased incidence and mortality in upper gastrointestinal cancer (ie, esophageal, gastric, or duodenal cancer). METHODS: We conducted a population-based cohort study of all patients with newly diagnosed GERD between July 1, 1979 and December 31, 2018 in Denmark, Finland, Norway, and Sweden. The exposure, negative upper endoscopy, was examined as a time-varying exposure, where participants contributed unexposed person-time from GERD diagnosis until screened and exposed person-time from the negative upper endoscopy. The incidence and mortality in upper gastrointestinal cancer were assessed using parametric flexible models, providing adjusted hazard ratios (HRs) with 95% confidence intervals (CIs). RESULTS: Among 1,062,740 patients with GERD (median age 58 years; 52% were women) followed for a mean of 7.0 person-years, 5324 (0.5%) developed upper gastrointestinal cancer and 4465 (0.4%) died from such cancer. Patients who had a negative upper endoscopy had a 55% decreased risk of upper gastrointestinal cancer compared with those who did not undergo endoscopy (HR, 0.45; 95% CI, 0.43-0.48), a decrease that was more pronounced during more recent years (HR, 0.34; 95% CI, 0.30-0.38 from 2008 onward), and was otherwise stable across sex and age groups. The corresponding reduction in upper gastrointestinal mortality among patients with upper endoscopy was 61% (adjusted HR, 0.39; 95% CI, 0.37-0.42). The risk reduction after a negative upper endoscopy in incidence and mortality lasted for 5 and at least 10 years, respectively. CONCLUSIONS: Negative upper endoscopy is associated with strong and long-lasting decreases in incidence and mortality in upper gastrointestinal cancer in patients with GERD.

Bariatric surgery volume by hospital and long-term survival: population-based NordOSCo data.

BACKGROUND: It is unclear whether annual hospital volume of bariatric surgery influences the long-term survival of individuals who undergo surgery for severe obesity. The hypothesis that higher annual hospital volume of bariatric surgery is associated with better long-term survival was evaluated. METHODS: This retrospective population-based study included patients who underwent bariatric surgery in Sweden and Finland between 1989 and 2020. Annual hospital volume was analysed for risk of all-cause mortality. Multivariable Cox regression provided HRs with 95 per cent confidence intervals adjusted for age, sex, co-morbidity, country, and type of bariatric procedure. RESULTS: Weight loss surgery was performed in 77 870 patients with a 0.5 per cent risk of postoperative death (mortality rate (MR) per 100 000 people 592.7, 95 per cent c.i. 575.0 to 610.9). Higher annual hospital volume of bariatric surgery was associated with a lower risk of all-cause mortality. The adjusted HRs were slightly more reduced for each quartile of annual hospital volume compared with the lowest quartile (MR per 100 000 people for lowest quartile 815.1, 95 per cent c.i. 781.7 to 849.9; for quartile II: HR 0.88, 95 per cent c.i. 0.81 to 0.96 (MR per 100 000 people 545.0, 512.0 to 580.1); for quartile III: HR 0.87, 0.78 to 0.97 (MR per 100 000 people 428.8, 395.5 to 465.0); for quartile IV: HR 0.82, 0.73 to 0.93 (MR per 100 000 people 356.0, 324.1 to 391.1)). In analyses restricted to laparoscopic surgery, volume and mortality were related only in the crude model (HR 0.86, 0.75 to 0.98), but not in the multivariable model (HR 0.97, 0.84 to 1.13) that compared highest and lowest quartiles. CONCLUSION: If there was a survival benefit associated with hospital volume, it may have been due to a faster uptake of laparoscopic surgery in the busier hospitals.

Cohort profile: Nordic Helicobacter Pylori eradication project (NordHePEP).

PURPOSE: This cohort description presents the Nordic Helicobacter Pylori Eradication Project (NordHePEP), a population-based cohort of patients having received eradication treatment for Helicobacter pylori (HP). The cohort is created with the main purpose of examining whether and to what extent HP eradication treatment influences the risk of gastrointestinal cancer. PARTICIPANTS: NordHePEP includes all adults (aged ≥18 years) having been prescribed and dispensed HP eradication treatment according to the nationwide complete drug registries in any of the five Nordic countries (Denmark, Finland, Iceland, Norway, or Sweden) between 1994 and 2020 (start and end year varies between countries). We have retrieved and merged individual-level data from multiple national registries, including drug, patient, cancer, population, and death registries. FINDINGS: The cohort includes 674,771 patients having received HP eradication treatment. During up to 23 years of follow-up, 59,292 (8.8%) participants were diagnosed with cancer (non-melanoma skin cancer excluded), whereof 15,496 (2.3%) in the gastrointestinal tract. FUTURE PLANS: We will analyse HP eradication treatment in relation to gastrointestinal cancer risk. Standardised incidence ratios will be calculated as the observed cancer incidence in the cohort divided by the expected cancer incidence, derived from the background population of the corresponding age, sex, and calendar year.

Menopausal hormone therapy and risk of oesophageal adenocarcinoma in a population-based cohort study.

BACKGROUND: Oesophageal adenocarcinoma is characterised by a strong male predominance. We aimed to test the hypothesis that menopausal hormonal therapy decreases the risk of oesophageal adenocarcinoma. METHODS: This population-based cohort study included all women who used systemic menopausal hormonal therapy (exposed) in Sweden between 2005 and 2018. For each exposed participant, five randomly selected female age-matched non-users of menopausal hormonal therapy (unexposed) were included. Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, smoking-related diagnoses, Helicobacter pylori eradication, use of non-steroidal anti-inflammatory drugs/aspirin, use of statins and hysterectomy. RESULTS: The study included 296,964 users of menopausal hormonal therapy and 1,484,820 non-users. Ever-users of menopausal hormonal therapy had an overall decreased risk of oesophageal adenocarcinoma (HR 0.78, 95% CI 0.63-0.97), which remained unchanged after further adjustment for gastro-oesophageal reflux disease (HR 0.78, 95% CI 0.63-0.97) and obesity/diabetes (HR 0.79, 95% CI 0.63-0.98). Decreased HRs were indicated both in users of oestrogen only (HR 0.82, 95% CI 0.60-1.12) and oestrogen combined with progestogen (HR 0.75, 95% CI 0.56-1.00). The risk reduction was more pronounced in users younger than 60 years (HR 0.57, 95% CI 0.38-0.86). CONCLUSIONS: Menopausal hormone therapy in women may decrease the risk of oesophageal adenocarcinoma.

Use of anti-androgenic 5α-reductase inhibitors and risk of oesophageal and gastric cancer by histological type and anatomical sub-site.

BACKGROUND: To investigate if anti-androgenic medications 5α-reductase inhibitors (5-ARIs) decrease the risk of developing oesophageal and gastric tumours, analysed by histological type and anatomical sub-site. METHODS: A Swedish population-based cohort study between 2005 and 2018 where men using 5-ARIs were considered exposed. For each exposed participant, ten male age-matched non-users of 5-ARIs (non-exposed) were included. Multivariable Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, calendar year, smoking, non-steroidal anti-inflammatory drugs/aspirin use, and statins use. Further adjustments were made depending on the tumour analysed. RESULTS: The cohort included 191,156 users of 5-ARIs and 1,911,560 non-users. Overall, the use of 5-ARIs was not associated with any statistically significantly reduced risk of oesophageal or cardia adenocarcinoma (adjusted HR 0.92, 95% CI 0.82-1.02) or gastric non-cardia adenocarcinoma (adjusted HR 0.90, 95% CI 0.80-1.02). However, the use of 5-ARIs indicated a decreased risk of oesophageal or cardia adenocarcinoma among obese or diabetic participants (adjusted HR 0.55, 95% CI 0.39-0.80) and a reduced risk of oesophageal squamous cell carcinoma (adjusted HR 0.49, 95% CI 0.37-0.65). CONCLUSION: Users of 5-ARIs may have a decreased risk of developing oesophageal or cardia adenocarcinoma among those obese or diabetic, and a decreased risk of oesophageal squamous cell carcinoma.

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

BACKGROUND: This systematic review and meta-analysis examined associations between serum levels of haemoglobin A1c (HbA1c) and glucose and the risk of gastric cancer. METHODS: MEDLINE, Embase, and Cochrane Library were searched for studies examining associations between serum levels of HbA1c or glucose and the risk of gastric cancer. Inclusion of studies, quality assessment, and data extraction were conducted independently by two authors. Pooled hazard ratios (HR) with 95% confidence intervals (CI) were synthesised using random-effects models. Cochran's Q test and I2 statistic were used to assess heterogeneity. RESULTS: Among 3473 identified studies, 12 were included. Of these, 5 studies examined HbA1c levels and 7 studies examined serum glucose levels. Serum HbA1c levels >6% were associated with an increased risk of gastric cancer (HR 1.36, 95% CI 1.06-1.74). When compared with the lowest glucose categories, the highest glucose categories were associated with a borderline increased risk of gastric cancer (HR 1.11, 95% CI 0.98-1.26). In subgroup analyses, studies that adjusted for Helicobacter pylori infection indicated stronger associations between elevated HbA1c levels and gastric cancer (HR 2.08, 95% CI 1.46-2.98) than those without such adjustment (HR 1.10, 95% CI 0.91-1.32). CONCLUSIONS: Long-standing poor glycaemic control may increase the risk of gastric cancer. REGISTRATION NUMBER: PROSPERO CRD42020157453.

Laryngeal and Pharyngeal Squamous Cell Carcinoma After Antireflux Surgery in the 5 Nordic Countries.

OBJECTIVE: The aim of this study was to clarify whether antireflux surgery prevents laryngeal and pharyngeal squamous cell carcinoma. SUMMARY BACKGROUND DATA: Gastroesophageal reflux disease (GERD) seems to increase the risk of laryngeal and pharyngeal squamous cell carcinoma. METHODS: All-Nordic (Denmark, Finland, Iceland, Norway, and Sweden) population-based cohort study of adults with documented GERD in 1980 to 2014. First, cancer risk after antireflux surgery was compared to the expected risk in the corresponding background population by calculating standardized incidence ratios (SIRs) with 95% confidence intervals (CIs). Second, cancer risk among antireflux surgery patients was compared to nonoperated GERD patients using multivariable Cox regression, providing hazard ratios (HR) with 95% CIs, adjusted for sex, age, calendar period, and diagnoses related to tobacco smoking, obesity, and alcohol overconsumption. RESULTS: Among 814,230 GERD patients, 47,016 (5.8%) underwent antireflux surgery. The overall SIRs and HRs of the combined outcome laryngeal or pharyngeal squamous cell carcinoma (n=39) were decreased after antireflux surgery [SIR=0.62 (95% CI 0.44-0.85) and HR=0.55 (95% CI 0.38-0.80)]. The point estimates were further decreased >10 years after antireflux surgery [SIR=0.48 (95% CI 0.26-0.80) and HR=0.47 (95% CI 0.26-0.85)]. The risk estimates of laryngeal squamous cell carcinoma were particularly decreased >10 years after antireflux surgery [SIR=0.28 (95% CI 0.08-0.72) and HR=0.23 (95% CI 0.08-0.69)], whereas no such decrease over time after surgery was found for pharyngeal squamous cell carcinoma. Analyses of patients with severe GERD (reflux esophagitis or Barrett esophagus) showed similar results. CONCLUSION: Antireflux surgery may decrease the risk of laryngeal squamous cell carcinoma and possibly also of pharyngeal squamous cell carcinoma.

Risk Factors for Suicide After Bariatric Surgery in a Population-based Nationwide Study in Five Nordic Countries.

OBJECTIVE: To identify risk factors for suicide after bariatric surgery. SUMMARY BACKGROUND DATA: Bariatric surgery reduces obesity-related mortality. However, it is for unclear reasons is associated with an increased risk of suicide. METHODS: This population-based cohort study included patients having undergone bariatric surgery in 1982 to 2012 in any of the 5 Nordic countries, with follow-up through 2012. Eleven potential risk factors of suicide (sex, age, comorbidity, surgery type, surgical approach, calendar year of surgery, history of depression or anxiety, psychosis, schizophrenia, mania, or bipolar disorder, personality disorder, substance use, and number of previously documented psychiatric diagnoses) were analyzed using Cox regression. RESULTS: Of 49,977 bariatric surgery patients, 98 (0.2%) committed suicide during follow-up. Women had a decreased risk of suicide compared to men (hazard ratio [HR] = 0.48, 95% confidence interval [CI] 0.33-0.77), although age and comorbidity did not influence this risk. Compared to gastric bypass, other types of bariatric surgery had lower risk of suicide (HR = 0.44, 95%CI 0.27-0.99). There was no difference in suicide risk between laparoscopic and open surgical approach. A history of depression or anxiety (HR = 6.87, 95%CI 3.97-11.90); mania, bipolar disorder, psychosis, or schizophrenia (HR = 2.70, 95%CI 1.14-6.37); and substance use (HR = 2.28, 95%CI 1.08-4.80), increased the risk of suicide. More of the above psychiatric diagnoses increased the risk of suicide (HR = 22.59, 95%CI 12.96-39.38 for ≥2 compared to 0 diagnoses). CONCLUSIONS: Although the risk of suicide is low, psychiatric disorders, male sex, and gastric bypass procedure seem to increase the risk of suicide after bariatric surgery, indicating a role for tailored preoperative psychiatric evaluation and postoperative surveillance.

Mortality, Reoperation, and Hospital Stay Within 90 Days of Primary and Secondary Antireflux Surgery in a Population-Based Multinational Study.

BACKGROUND & AIMS: Absolute rates and risk factors of short-term outcomes after antireflux surgery remain largely unknown. We aimed to clarify absolute risks and risk factors for poor 90-day outcomes of primary laparoscopic and secondary antireflux surgery. METHODS: This population-based cohort study included patients who had primary laparoscopic or secondary antireflux surgery in the 5 Nordic countries in 2000-2018. In addition to absolute rates, we analyzed age, sex, comorbidity, hospital volume, and calendar period in relation to all-cause 90-day mortality (main outcome), 90-day reoperation, and prolonged hospital stay (≥2 days over median stay). Multivariable logistic regression provided odds ratios (ORs) with 95% confidence intervals (95% CI), adjusted for confounders. RESULTS: Among 26,193 patients who underwent primary laparoscopic antireflux surgery, postoperative 90-day mortality and 90-day reoperation rates were 0.13% (n = 35) and 3.0% (n = 750), respectively. The corresponding rates after secondary antireflux surgery (n = 1 618) were 0.19% (n = 3) and 6.2% (n = 94). Higher age (56-80 years vs 18-42 years: OR, 2.66; 95% CI 1.03-6.85) and comorbidity (Charlson Comorbidity Index ≥2 vs 0: OR, 6.25; 95% CI 2.42-16.14) increased risk of 90-day mortality after primary surgery, and higher hospital volume suggested a decreased risk (highest vs lowest tertile: OR, 0.58; 95% CI, 0.22-1.57). Comorbidity increased the risk of 90-day reoperation. Higher age and comorbidity increased risk of prolonged hospital stay after both primary and secondary surgery. Higher annual hospital volume decreased the risk of prolonged hospital stay after primary surgery (highest vs lowest tertile: OR, 0.74; 95% CI, 0.67-0.80). CONCLUSION: These findings suggest that laparoscopic antireflux surgery has an overall favorable safety profile in the treatment of gastroesophageal reflux disease, particularly in younger patients without severe comorbidity who undergo surgery at high-volume centers.

Proton Pump Inhibitor and Clopidogrel Use After Percutaneous Coronary Intervention and Risk of Major Cardiovascular Events.

PURPOSE: Due to shared hepatic metabolism, concomitant medication with a proton pump inhibitor (PPI) and clopidogrel might reduce the effectiveness of clopidogrel in the prevention of cardiovascular events after percutaneous coronary intervention (PCI). We aimed to examine the risk of major cardiovascular events after PCI comparing patients who used clopidogrel together with PPI with those who used clopidogrel alone. METHODS: This Swedish nationwide cohort study included patients who received clopidogrel after primary PCI in 2005-2019. Patients were followed for up to 12 months after PCI. Data were retrieved from the Swedish Prescribed Drug Registry, Patient Registry, Cancer Registry, and Cause of Death Registry. Multivariable Cox regression provided hazard ratios (HRs) with 95% confidence intervals (CIs) for cardiovascular events comparing PPI users (exposed) with non-users of PPI (non-exposed). The HRs were adjusted for sex, age, comorbidity, calendar period, obesity, diabetes, anti-diabetic medication, tobacco-related diseases, hypertension, and congestive heart failure. RESULTS: The cohort included 99,836 patients who received clopidogrel after primary PCI. Among these, 35,772 (35.8%) received concomitant PPI. Compared to non-users, PPI users had increased adjusted HRs of all study outcomes, i.e., the main outcome myocardial infarction (HR = 1.23, 95% CI 1.15-1.32) and the secondary outcomes coronary heart disease (HR = 1.28, 95% CI 1.24-1.33), stroke (HR = 1.21, 95% CI 1.05-1.40), and death due to coronary heart disease (HR = 1.52, 95% CI 1.37-1.69). The results were similar in analyses including both primary and secondary PCIs. CONCLUSIONS: In patients who receive clopidogrel after PCI, concomitant use of PPI seems to increase the risk of major cardiovascular events.

Improved prognosis in gastric adenocarcinoma among metformin users in a population-based study.

BACKGROUND: Metformin may improve the prognosis in gastric adenocarcinoma, but the existing literature is limited and contradictory. METHODS: This was a Swedish population-based cohort study of diabetes patients who were diagnosed with gastric adenocarcinoma in 2005-2018 and followed up until December 2019. The data were retrieved from four national health data registries: Prescribed Drug Registry, Cancer Registry, Patient Registry and Cause of Death Registry. Associations between metformin use before the gastric adenocarcinoma diagnosis and the risk of disease-specific and all-cause mortality were assessed using multivariable Cox proportional hazard regression. The hazard ratios (HRs) and 95% confidence intervals (CIs) were adjusted for sex, age, calendar year, comorbidity, use of non-steroidal anti-inflammatory drugs or aspirin, and use of statins. RESULTS: Compared with non-users, metformin users had a decreased risk of disease-specific mortality (HR 0.79, 95% CI 0.67-0.93) and all-cause mortality (HR 0.78, 95% CI 0.68-0.90). The associations were seemingly stronger among patients of female sex (HR 0.66, 95% CI 0.49-0.89), patients with tumour stage III or IV (HR 0.71, 95% CI 0.58-0.88), and those with the least comorbidity (HR 0.71, 95% CI 0.57-0.89). CONCLUSIONS: Metformin use may improve survival in gastric adenocarcinoma among diabetes patients.

Prediction Model of Long-term Survival After Esophageal Cancer Surgery.

OBJECTIVE: We aimed to develop prediction models for estimating the long-term survival in patients who have undergone surgery for esophageal cancer. BACKGROUND: Few prediction models have been developed for the long-term survival in esophageal cancer patients. METHODS: This nationwide Swedish population-based cohort study included 1542 patients who survived for ≥90 days after esophageal cancer surgery between 1987 and 2010, with follow-up until 2016. Risk prediction models for 1-, 3-, and 5-year all-cause mortality and 3- and 5-year disease-specific mortality were developed using logistic regression. Candidate predictors were established and readily identifiable prognostic factors. The performance of the models was assessed by the area under receiver-operating characteristic curve (AUC) with interquartile range (IQR) using bootstrap cross-validation and risk calibration. RESULTS: Predictors included in all models were age, sex, pathological tumor stage, tumor histology, and resection margin status. The models also included various additional predictors depending on the outcome, that is, education level, neoadjuvant therapy, reoperation (within 30 d of primary surgery) and comorbidity (Charlson comorbidity index). The AUC statistics after cross-validation were 0.71 (IQR 0.69-0.74) for 1-year, 0.77 (IQR 0.75-0.80) for 3-year, and 0.78 (IQR 0.76-0.81) for 5-year all-cause mortality. The corresponding values were 0.76 (IQR 0.74-0.79) for 3-year and 0.77 (IQR 0.71-0.83) for 5-year disease-specific mortality. All models showed good agreement between the observed and predicted risks. CONCLUSIONS: These models showed good performance for predicting long-term survival after esophageal cancer surgery and may thus be useful for patients in planning their lives and to guide the postoperative treatment and follow-up.

Esophageal Adenocarcinoma After Antireflux Surgery in a Cohort Study From the 5 Nordic Countries.

OBJECTIVE: We aimed to clarify the long-term risk development of EAC after antireflux surgery. SUMMARY OF BACKGROUND DATA: Gastroesophageal reflux disease (GERD) increases EAC risk, but whether antireflux surgery prevents EAC is uncertain. METHODS: Multinational, population-based cohort study including individuals with GERD from all 5 Nordic countries in 1964-2014. First, EAC risk after antireflux surgery in the cohort was compared with the corresponding background population by calculating standardized incidence ratios (SIRs) with 95% confidence intervals (95% CIs). Second, multivariable Cox proportional hazards regression, providing hazard ratios (HRs) with 95% CIs, compared EAC risk in GERD patients with antireflux surgery with those with nonsurgical treatment. RESULTS: Among 942,071 GERD patients, 48,863 underwent surgery and 893,208 did not. Compared to the corresponding background population, EAC risk did not decrease after antireflux surgery [SIR 4.90 (95% CI 3.62-6.47) 1-<5 years and SIR 4.57 (95% CI 3.44-5.95) ≥15 years after surgery]. Similarly, no decrease was found for patients with severe GERD (esophagitis or Barrett esophagus) after surgery [SIR 6.09 (95% CI 4.39-8.23) 1-<5 years and SIR = 5.27 (95% CI 3.73-7.23) ≥15 years]. The HRs of EAC were stable comparing the surgery group with the nonsurgery group with GERD [HR 1.71 (95% CI 1.26-2.33) 1-<5 years and HR 1.69 (95% CI 1.24-2.30) ≥15 years after treatment], or for severe GERD [HR 1.56 (95% CI 1.11-2.20) 1-<5 years and HR 1.57 (95% CI 1.08-2.26) ≥15 years after treatment]. CONCLUSIONS: Surgical treatment of GERD does not seem to reduce EAC risk.

Hospital Volume of Antireflux Surgery in Relation to Endoscopic and Surgical Re-interventions.

OBJECTIVE: To test the hypothesis that higher hospital volume decreases endoscopic and surgical re-intervention rates after antireflux surgery. BACKGROUND: Antireflux surgery for gastro-esophageal reflux disease is followed by varying rates of re-interventions. Whether hospital volume influences re-intervention rates is uncertain. METHODS: This population-based cohort study used nationwide data from Denmark, Finland, and Sweden for patients having undergone primary antireflux surgery. Hospitals were divided into tertiles based upon annual volume, that is, 3 equal-sized groups. The outcomes were 30-day surgical re-intervention, endoscopic re-intervention, and secondary antireflux surgery. Multivariable Cox regression provided hazard ratios (HRs) with 95% confidence intervals (CIs) for risk of the first outcome occurrence. Incidence rate ratios were calculated to count all outcome occurrences. All risk estimates were adjusted for age, sex, comorbidity, type of antireflux surgery, year of surgery, and country. RESULTS: Among 33,060 patients and a median follow-up of 12 years after antireflux surgery, the frequencies of 30-day re-intervention, endoscopic re-intervention, and secondary antireflux surgery were 1.2%, 4.6%, and 7.0%, respectively. When comparing the highest with the lowest tertiles, higher hospital volume did not decrease HRs of 30-day re-intervention (adjusted HR = 1.14, 95% CI 0.73-1.77), endoscopic re-intervention (HR = 1.21, 95% CI 0.96-1.51), or secondary antireflux surgery (HR = 1.28, 95% CI 1.05-1.54), but rather increased point estimates. The incidence rate ratios showed similar patterns. CONCLUSIONS: Higher hospital volume of primary antireflux surgery may not decrease risk of endoscopic or surgical re-intervention, suggesting that centralization will not decrease rates of postoperative complications or recurrence of gastro-esophageal reflux disease.

Development and Validation of a Risk Prediction Model for Esophageal Squamous Cell Carcinoma Using Cohort Studies.

INTRODUCTION: Esophageal squamous cell carcinoma (ESCC) carries a poor prognosis, but earlier tumor detection would improve survival. We aimed to develop and externally validate a risk prediction model based on exposure to readily available risk factors to identify high-risk individuals of ESCC. METHODS: Competing risk regression modeling was used to develop a risk prediction model. Individuals' absolute risk of ESCC during follow-up was computed with the cumulative incidence function. We used prospectively collected data from the Nord-Trøndelag Health Study (HUNT) for model derivation and the UK Biobank cohort for validation. Candidate predictors were age, sex, tobacco smoking, alcohol consumption, body mass index (BMI), education, cohabitation, physical exercise, and employment. Model performance was validated internally and externally by evaluating model discrimination using the area under the receiver-operating characteristic curve (AUC) and model calibration. RESULTS: The developed risk prediction model included age, sex, smoking, alcohol, and BMI. The AUC for 5-year risk of ESCC was 0.76 (95% confidence interval [CI], 0.58-0.93) in the derivation cohort and 0.70 (95% CI, 0.64-0.75) in the validation cohort. The calibration showed close agreement between the predicted cumulative risk and observed probabilities of developing ESCC. Higher net benefit was observed when applying the risk prediction model than considering all participants as being at high risk, indicating good clinical usefulness. A web tool for risk calculation was developed: https://sites.google.com/view/escc-ugis-ki. DISCUSSION: This ESCC risk prediction model showed good discrimination and calibration and validated well in an independent cohort. This readily available model can help select high-risk individuals for preventive interventions.

Patient Age and Survival After Surgery for Esophageal Cancer.

BACKGROUND: Esophagectomy for esophageal cancer is associated with a substantial risk of life-threatening complications and a limited long-term survival. This study aimed to clarify the controversial questions of how age influences short-term and long-term survival. METHODS: This population-based cohort study included almost all patients who underwent curatively intended esophagectomy for esophageal cancer in Sweden in 1987-2010, with follow-up through 2016. The exposure was age, analyzed both as a continuous and categorical variable. The probability of mortality was computed using a novel flexible parametric model approach. The reported probabilities are proper measures of the risk of dying, and the related odds ratios (OR) are therefore more suitable measures of association than hazard ratios. The outcomes were 90-day all-cause mortality, 5-year all-cause mortality, and 5-year disease-specific mortality. A novel flexible parametric model was used to derive the instantaneous probability of dying and the related OR along with 95% confidence intervals (CIs), adjusted for sex, education, comorbidity, tumor histology, pathological tumor stage, and resection margin status. RESULTS: Among 1737 included patients, the median age was 65.6 years. When analyzed as a continuous variable, older age was associated with slightly higher odds of 90-day all-cause mortality (OR 1.05, 95% CI 1.02-1.07), 5-year all-cause mortality (OR 1.02, 95% CI 1.01-1.03), and 5-year disease-specific mortality (OR 1.01, 95% CI 1.01-1.02). Compared with patients aged < 70 years, those aged 70-74 years had no increased risk of any mortality outcome, while patients aged ≥ 75 years had higher odds of 90-day mortality (OR 2.85, 95% CI 1.68-4.84), 5-year all-cause mortality (OR 1.56, 95% CI 1.27-1.92), and 5-year disease-specific mortality (OR 1.38, 95% CI 1.09-1.76). CONCLUSIONS: Patient age 75 years or older at esophagectomy for esophageal cancer appears to be an independent risk factor for higher short-term mortality and lower long-term survival.