Proton Pump Inhibitor Use and Risk of Developing Alzheimer’s Disease or Vascular Dementia: A Case–Control Analysis

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.

Proton Pump Inhibitors and Cognitive Health: Review on Unraveling the Dementia Connection and Co-morbid Risks

Dementia, an international health issue distinguished by the impairment of daily functioning due to cognitive decline, currently affects more than 55 million people worldwide, with the majority residing in low-income and middle-income countries. Globally, dementia entails significant economic burdens in 2019, amounting to a cost of 1.3 trillion US dollars. Informal caregivers devote considerable hours to providing care for those affected. Dementia imposes a greater caregiving and disability-adjusted life-year burden on women. A recent study has established a correlation between prolonged Proton Pump Inhibitor (PPI) usage and dementia, in addition to other neurodegenerative conditions. PPIs are frequently prescribed to treat peptic ulcers and GERD (gastroesophageal reflux disease) by decreasing stomach acid secretion. They alleviate acid-related symptoms through the inhibition of acid-secreting H+-K+ ATPase. In a number of observational studies, cognitive decline and dementia in the elderly have been linked to the use of PPIs. The precise mechanism underlying this relationship is unknown. These drugs might also alter the pH of brain cells, resulting in the accumulation of amyloid-beta (Aβ) peptides and the development of Alzheimer's disease (AD). Despite the compelling evidence supporting the association of PPIs with dementia, the results of studies remain inconsistent. The absence of a correlation between PPI use and cognitive decline in some studies emphasizes the need for additional research. Chronic PPI use can conceal underlying conditions, including cancer, celiac disease, vitamin B12 deficiency, and renal injury, highlighting dementia risk and the need for further investigations on cognitive health.

Proton pump inhibitors and dementia: what association?

Several recent studies have suggested an association between proton pump inhibitors and the development of cognitive changes.

Objective

To assess the existence of this association.

Methods

A comprehensive literature search was conducted including guidelines, meta-analyses, systematic reviews, observational and experimental studies published between February 2011 and February 2021.

Results

The initial research identified 393 articles, 28 of which were included: 8 systematic reviews, 1 clinical trial, 15 observational studies, 3 case-control studies, and 1 cross-sectional observational study.

Conclusions

Most studies classified with the highest level of evidence found no statistically significant association between the use of proton pump inhibitors and the development of cognitive impairment or dementia.

Time-Varying Use of Proton Pump Inhibitors and Cognitive Impairment and Dementia: A Real-World Analysis from Germany

BACKGROUND

Cumulative evidence of dementia risk in patients taking proton pump inhibitors (PPIs) is still inconclusive, probably due to a variety of study designs.

OBJECTIVE

This study aimed to compare how the association between dementia risk and use of PPIs differs by different outcome and exposure definitions.

METHODS

We conceptualized a target trial using claims data with 7,696,127 individuals aged 40 years or older without previous dementia or mild cognitive impairment (MCI) from the Association of Statutory Health Insurance Physicians in Bavaria. Dementia was defined as either including or excluding MCI to compare how the results alter by different outcome definitions. We used weighted Cox models to estimate the PPI initiation effect on dementia risk and weighted pooled logistic regression to assess the effect of time-varying use versus non-use during 9 years of study period, including 1 year of wash-out period (2009-2018). The median follow-up time of PPI initiators and non-initiators was 5.4 and 5.8 years, respectively. We also evaluated the association between each PPI agent (omeprazole, pantoprazole, lansoprazole, esomeprazole, and combined use) and dementia risk.

RESULTS

A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk. A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk.A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk.A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk.A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk.A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk.A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk.A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk.A total of 105,220 (3.6%) PPI initiators and 74,697 (2.6%) non-initiators were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.04 [95% confidence interval (CI) 1.03-1.05]. The HR for time-varying PPI use versus non-use was 1.85 (1.80-1.90). When MCI was included in the outcome, the number of outcomes increased to 121,922 in PPI initiators and 86,954 in non-initiators, but HRs remained similar, showing 1.04 (1.03-1.05) and 1.82 (1.77-1.86), respectively. Pantoprazole was the most frequently used PPI agent. Although the estimated HRs for the time-varying use effect of each PPI showed different ranges, all agents were associated with an increased dementia risk.

CONCLUSION

Our large study supports existing evidence that PPI use is related to an increased risk of dementia.

Signal and Noise: Proton Pump Inhibitors and the Risk of Dementia?

The association between proton pump inhibitor (PPI) use and dementia remains controversial. This cohort study re-examines this issue, addressing shortcomings identified in previous publications using a population-based and a high-dimension propensity-score matched cohort to follow patients for up to 22 years. Cox regression models using baseline characteristics, a lag period, and time-varying variables were used to examine the risk of dementia by cumulative PPI exposure. High-dose PPI users (> 180 days of use) had significantly higher risk of dementia in crude Cox models. After adjustment for medical diagnoses and prescription drug use, these associations disappeared. Among high-dose users starting PPI therapy between 46 and 55 years old, the unadjusted hazard ratio (HR) was 1.55 (95% confidence interval (CI) 1.14, 2.10); the adjusted hazard ratio (aHR) was 1.10 (95% CI 0.80, 1.51). For high-dose users starting therapy between 56 and 65 years, HR = 1.22 (95% CI1.03, 1.44); aHR = 0.99 (95% CI 0.83, 1.17). High-dose users between the ages of 66 and 75 years had no association with the risk of dementia. The use of lag models or time-varying parameters similarly found some association with dementia in crude, but not multivariable Cox models. Although high-dose PPI users were more likely to develop dementia, they were more likely to be diagnosed with dementia risk factors, such as diabetes and cardiovascular disease, which are risk factors for dementia. Controlling for these conditions using multivariable models or a propensity-score matched cohort eliminated this association.

Associations between proton pump inhibitors and Alzheimer’s disease: a nested case–control study using a Korean nationwide health screening cohort

Background

Safety concerns against the use of proton pump inhibitors (PPIs) based on the risk of dementia, especially Alzheimer’s disease (AD), remain controversial. Here, we investigated the likelihood of AD depending on previous PPI exposure, use duration, and PPI generation.

Methods

This nested case–control study comprised 17,225 AD patients who were 1:4 matched with 68,900 controls for age, sex, income, and region of residence from Korean National Health Insurance Service-Health Screening Cohort data between 2002 and 2015 using propensity-score matching method. Conditional and unconditional logistic regression analyses were used to evaluate the effects of previous PPI use on AD adjusting for multiple covariates.

Results

Prior PPI use increased likelihood for AD in current and past PPI users (adjusted odds ratio 1.36 [95% confidence interval (CI) = 1.26–1.46] and 1.11 [95% CI = 1.04–1.18], respectively). Participants with either < 30 days, 30–90 days, or > 90 days of PPI prescription showed higher odds for AD (1.13 [95% CI = 1.07–1.19]; 1.18 [95% CI = 1.10–1.27]; 1.26 [95% CI = 1.16–1.36], respectively). Participants with either 1st-generation or 2nd-generation PPIs demonstrated higher incidences of AD in those with < 30 days (1.14 [95% CI = 1.07–1.22] and 1.13 [95% CI = 1.05–1.22], respectively), 30–90 days (1.19 [95% CI = 1.09–1.30] and 1.17 [95% CI = 1.05–1.29], respectively), or > 90 days (1.18 [95% CI = 1.07–1.30] and 1.27 [95% CI = 1.14–1.43], respectively) of prescription.

Conclusions

Prior PPI use, regardless of current or past exposure, duration of use, or use of 1st- or 2nd-generation PPIs, may increase likelihood of AD, providing supportive evidence of previous pharmacoepidemiologic studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13195-022-01032-5.

Regular proton pump inhibitor use and incident dementia: population-based cohort study

BACKGROUND

To examine the association between regular use of proton pump inhibitors and the risk of incident dementia, including dementia subtypes, and whether the association differs between APOE genotypes.

METHODS

Based on a prospective analysis of data from the UK Biobank, 501,002 individuals (female, 54.4%) aged between 40 and 70 years, who had no prevalent dementia at baseline, were enrolled between 2006 and 2010 and followed up to 2018. We compared all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD) incidence rates between proton pump inhibitor users and non-users by the Cox proportional hazard model.

RESULTS

During 4,438,839 person-years of follow-up (median length of follow-up, 9.0 years), there were 2505 incident cases of all-cause dementia, including 932 cases of AD and 524 cases of VaD. The incident rate of all-cause dementia among proton pump inhibitor users was 1.06 events per 1000 person-years, compared with 0.51 events per 1000 person-years among non-users. After adjustment for multiple confounders and indications, the hazard ratios (HRs) of the proton pump inhibitor users were 1.20 (95% CI, 1.07-1.35) for incident all-cause dementia, 1.23 (95% CI, 1.02-1.49) for incident AD, and 1.32 (95% CI, 1.05-1.67) for incident VaD. In addition, the association between proton pump inhibitor use and all-cause dementia differed by APOE genotype (P for interaction = 0.048). Among APOE ε4 heterozygotes, the fully adjusted HR of proton pump inhibitor use was 1.46 (95% CI, 1.22-1.75) and 1.68 (95% CI, 1.36-2.07), especially for individuals aged 65 years and older.

CONCLUSIONS

The finding of this large population-based cohort study indicates that the use of proton pump inhibitors is associated with an increased risk of incident dementia, particularly among APOE ε4 heterozygotes.

Emulating a target trial of proton pump inhibitors and dementia risk using claims data

BACKGROUND

Understanding the adverse effects of proton pump inhibitors (PPIs) is important due to their widespread use, but the available evidence for an increased dementia risk among patients taking PPIs is inconclusive. The present study aimed to estimate the causal effect of PPIs on the risk of dementia by target trial emulation and time-varying exposure modeling.

METHODS

Using claims data of 2,698,176 insured people of a large German statutory health insurer, we conceptualized a target trial in which individuals aged 40 years and older were classified as PPI initiators or non-initiators between 2008 and 2018, and followed until diagnosis of dementia, death, loss to follow-up or end of study. Incidence of dementia (ICD-10 codes F00, F01, F03, F05.1, G30, G31.0, G31.1, G31.9, and F02.8+G31.82) was defined applying a 1-year lag window. We used weighted Cox models to estimate the effect of PPI initiation vs. non-initiation on dementia risk and weighted pooled logistic regression to estimate the effect of time-varying use vs. non-use.

RESULTS

29,746 PPI initiators (4.4%) and 26,830 non-initiators (1.3%) were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio (HR) for dementia was 1.54 (95% confidence interval [CI]: 1.51-1.58). The HR for time-dependent PPI use vs. non-use was 1.56 (95% CI: 1.50-1.63). Differentiated subtypes, including unspecified dementia, Alzheimer's disease (AD), and vascular dementia (VaD), showed increased risk by PPI initiation and time-varying PPI use.

CONCLUSIONS

This study suggests that PPI initiation and time-varying PPI use may increase overall dementia risk.

Gastric acid suppressants and cognitive decline in people with or without cognitive impairment

INTRODUCTION

Studies suggest associations between proton pump inhibitors (PPIs) and dementia risk; however, many neither considered histamine-2 receptor antagonists (H2RAs) nor baseline cognitive status.

METHODS

Participants (National Alzheimer's Coordinating Center Database; 2005-2021) using a PPI or H2RA were compared. Covariate-adjusted Cox regression was used to estimate hazard ratios (HR) for progression from normal cognition to mild cognitive impairment (MCI), and from MCI to dementia over 5 years. In a propensity-score-matched subsample of mild-moderate Alzheimer's disease (AD), mixed-effects negative binomial regression was used to estimate decline in delayed recall memory.

RESULTS

Compared to PPI, H2RA use was associated with earlier progression from MCI to dementia (HR = 1.40 [1.09-1.81]; n = 1701), and with faster memory decline in AD over time (rate ratio = 0.76 [0.64-0.92]; n = 628), but not with progression from normal cognition to MCI (HR = 0.94 [0.71-1.24]; n = 2784).

DISCUSSION

Compared to PPIs, H2RAs were associated with cognitive decline, specifically among people with pre-existing cognitive impairment.

No association between acid suppressant use and risk of dementia: an updated meta-analysis

PURPOSE

Findings from large observational studies on whether the use of acid suppressants increases the risk of dementia have been inconsistent. Since proton pump inhibitors (PPI) and histamine-2 receptor antagonists (H2RA) are the most commonly used acid suppressants in clinical practice, we performed a meta-analysis to examine the influence of PPI and H2RA on the risk of dementia.

METHODS

A systematic search was performed on the PubMed, EMBASE, and Cochrane Library databases to identify studies published up to April, 2021. Studies that reported adjusted hazard ratio (HR) with 95% confidence intervals (CI) for the associations of interest were included. Data in the included studies were pooled using the random-effects model for meta-analysis. Statistical analysis was performed using Stata version 12.0 software.

RESULTS

Seventeen studies involving 1,251,562 participants were included. It was found that PPI users were not likely to develop dementia compared with those not taking PPI (HR = 0.98, 95% CI: 0.85-1.13). Subgroup analysis based on publication year, location, mean age, duration of PPI use, and female proportion also revealed no association between PPI use and dementia risk. Similarly, H2RA use was not associated with the risk of dementia, as indicated by the pooled HR of 1.20 (95% CI: 0.98-1.47).

CONCLUSION

Results of this meta-analysis suggest that PPI and H2RA do not increase the risk of dementia. These results may be used to inform the clinical application of acid suppressants. However, further randomized controlled trials are needed to confirm the present conclusions.

The Janus-like Association between Proton Pump Inhibitors and Dementia

Early pharmacoepidemiological studies suggested that Proton Pump Inhibitors (PPIs) might increase the risk of Alzheimer’s Disease (AD) and non-AD related dementias. These findings were supported by preclinical studies, specifically stressing the proamyloidogenic and indirect anticholinergic effects of PPIs. However, further large-scale pharmacoepidemiological studies showed inconsistent results on the association between PPIs and dementia. Pharmacodynamically, these findings might be related to the LXR/RXR-mediated amyloid clearance effect and anti-inflammatory action of PPIs. Further aspects that influence PPI effects on AD are related to patient-specific pharmacokinetic and pharmacogenomic characteristics. In conclusion, a personalized (individualized) medicinal approach is necessary to model and predict the potential harmful or beneficial effects of PPIs in AD and non-AD-related dementias in the future.

Lack of association between proton pump inhibitor use and decline in cognitive performance in the ELSA-Brasil cohort

OBJECTIVE

The study aims to investigate the longitudinal association of use and time of use of proton pump inhibitors (PPIs) with decreased performance in three cognitive tests.

METHODS

Prospective cohort study included 7115 participants with mean age of 58.9 years at baseline (2008-2010) who participated in the second wave (2012-2014) of ELSA-Brasil (average interval between visits = 3.9 years (range: 1.7 to 6.0 years)). Cognitive performance was assessed by tests of memory, phonemic and semantic verbal fluency, and the trail making test, applied to both waves. Associations with the use and time of use of PPIs at baseline were investigated using linear models with mixed effects after adjusting for confounding factors.

RESULTS

At baseline, 7.4% (529) of the participants used PPIs on a regular basis. After all adjustments, the interaction term use of PPI × age was not statistically significant for the cognitive tests evaluated, indicating that the use of PPI at baseline was not associated with a more accelerated decline in cognitive performance between waves. The interaction term PPI use × age was not statistically significant, in any of the categories of medication use time, any of the cognitive function tests evaluated, indicating that PPI use time is not associated with decrease in cognitive scores as the time interval between visits increases.

CONCLUSION

In this cohort middle-aged and elderly adults, after average interval of 3.9 years (relatively short time to detect cognitive decline in a young cohort), the use and time of use of PPIs at the beginning of the study were not associated with a decline in cognitive performance in these tests between visits.

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.

Promoting Successful Cognitive Aging: A Ten-Year Update

A decade has passed since we published a comprehensive review in this journal addressing the topic of promoting successful cognitive aging, making this a good time to take stock of the field. Because there have been limited large-scale, randomized controlled trials, especially following individuals from middle age to late life, some experts have questioned whether recommendations can be legitimately offered about reducing the risk of cognitive decline and dementia. Despite uncertainties, clinicians often need to at least make provisional recommendations to patients based on the highest quality data available. Converging lines of evidence from epidemiological/cohort studies, animal/basic science studies, human proof-of-concept studies, and human intervention studies can provide guidance, highlighting strategies for enhancing cognitive reserve and preventing loss of cognitive capacity. Many of the suggestions made in 2010 have been supported by additional research. Importantly, there is a growing consensus among major health organizations about recommendations to mitigate cognitive decline and promote healthy cognitive aging. Regular physical activity and treatment of cardiovascular risk factors have been supported by all of these organizations. Most organizations have also embraced cognitively stimulating activities, a heart-healthy diet, smoking cessation, and countering metabolic syndrome. Other behaviors like regular social engagement, limiting alcohol use, stress management, getting adequate sleep, avoiding anticholinergic medications, addressing sensory deficits, and protecting the brain against physical and toxic damage also have been endorsed, although less consistently. In this update, we review the evidence for each of these recommendations and offer practical advice about behavior-change techniques to help patients adopt brain-healthy behaviors.

Acid suppressants use and the risk of dementia: A population-based propensity score-matched cohort study

In this population-based propensity score matched (PSM) cohort study, we aimed to investigate the risk of developing dementia with the use of acid suppressants, including proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2 antagonists). Cohorts of PPI users (n = 2,778), H2 antagonist users (n = 6,165), and non-users (n = 86,238) were selected from a dataset covering the years 2000 to 2010 in Taiwan’s National Health Insurance Research Database. Patients in the three groups were PSM at a ratio of 1:1 within each comparison cohort (CC). Three CCs were created: (1) PPI users compared to non-users (CC1, n = 2,583 pairs); (2) H2 antagonist users compared to non-users (CC2, n = 5,955 pairs); and (3) PPI users compared to H2 antagonist users (CC3, n = 2,765 pairs). A multivariable robust Cox proportional hazard model was used to estimate the adjusted hazard ratio (aHR) and the 95% confidence interval (CI) for the risk of developing dementia. The multivariable analysis results show that the aHR of developing dementia during the follow-up period was 0.72 (CC1: 95% CI = 0.51–1.03, P = 0.07) for PPI users and 0.95 (CC2: 95% CI = 0.74–1.22, P = 0.69) for H2 antagonist users, when compared to non-users. Between the patients using acid suppressants, there was no difference between PPI and H2 antagonist users in the risk of developing dementia (CC3: aHR = 0.82, 95% CI = 0.58–1.17, P = 0.28). In conclusion, no association was observed between the use of acid suppressants and the risk of developing dementia in any of the three CCs. Further, randomized controlled trials are warranted to confirm this relationship.

Clinical Use of Acid Suppressants and Risk of Dementia in the Elderly: A Pharmaco-Epidemiological Cohort Study

BACKGROUND

Results of studies regarding the potential link between acid suppressant use and dementia risk are inconsistent. This study aimed to evaluate the association of cumulative exposure to histamine 2 receptor antagonists (H2RAs) and proton pump inhibitors (PPIs) with dementia risk in an Asian older cohort aged ≥65 years.

METHODS

Patients initiating H2RA (the H2RA user cohort, n = 21,449) or PPI (the PPI user cohort, n = 6584) and those without prescription for H2RA (the H2RA non-user cohort, n = 21,449) or PPI (the PPI non-user cohort, n = 6584) between 1 January 2000 and 31 December 2005 without a prior history of dementia were identified from Taiwan's National Health Insurance Research Database (NHIRD). The outcome of interest was all-cause dementia. Patients' exposure to H2RAs or PPIs was followed-up from dates of initial prescription to the earliest outcome of incident dementia, death, or the end of 2013. Potential associations between acid suppressant use and dementia risk were analyzed using time-dependent Cox regression estimated hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

After mutual adjustment for H2RA and PPI use and other potential confounders, patients with H2RA use had significantly higher risk of developing dementia as compared to those not treated with H2RAs (adjusted HR, 1.84; 95% CI, 1.49-2.20). Likewise, PPI users had significantly elevated risk of dementia compared to PPI non-users (adjusted HR, 1.42; 95% CI, 1.07-1.84).

CONCLUSIONS

Our results indicate that exposures to H2RAs and PPIs are associated with increased dementia risk.

Proton pump inhibitors do not increase the risk of dementia: a systematic review and meta-analysis of prospective studies

Published studies have reported variable results on the association between duration of proton pump inhibitor (PPI) use and the risk of dementia. An extensive literature search was performed in PubMed, Embase, Google Scholar, and Cochrane for studies examining the risk of cognitive decline and dementia among PPI users versus non-PPI users in prospective studies. Retrospective database linkage studies, case reports, case series, editorials, uncontrolled cohort studies, cross-sectional studies, and review articles were excluded. Primary outcome was pooled hazard rate (HR) of any dementia among PPI users compared with non-PPI users. Secondary outcomes were pooled HR of Alzheimer's dementia (AD) and risk with long-term PPI follow-up (more than 5 years) studies. Meta-analysis outcomes, heterogeneity (I2), and meta-regression (for the effect of covariates) were derived by statistical software R and Open meta-analyst. A total of six studies (one RCT and five prospective) with 308249 subjects, average age of 75.8 ± 5.2 years, and follow-up of 5 (range 1.5-11) years were included in the analysis. Pooled HR of any dementia was 1.16 (n = 6, 95% confidence interval (CI) = 0.86-1.47). Results remained unchanged when only studies with long-term PPI use (more than 5 years) were analyzed (n = 4, pooled HR 1.10, 95% CI 0.66-1.53). Finally, the pooled HR for AD was 1.06 (n = 3, 95% CI 0.70-1.41). There was substantial heterogeneity among inclusion studies (I2 = 93%). Meta-regression did not demonstrate a significant role of age at study start (P = 0.1) or duration of PPI use (P = 0.62) to incident dementia. The results of this systematic review and meta-analysis do not show a significant relationship between PPI use and dementia in prospective studies with at least a 5-year follow-up.

Proton pump inhibitors and dementia risk: Evidence from a cohort study using linked routinely collected national health data in Wales, UK

OBJECTIVES

Proton pump inhibitors (PPIs) are commonly prescribed for prevention and treatment of gastrointestinal conditions or for gastroprotection from other drugs. Research suggests they are linked to increased dementia risk. We use linked national health data to examine the association between PPI use and the development of incident dementia.

METHODS AND FINDINGS

A population-based study using electronic health-data from the Secure Anonymised Information Linkage (SAIL) Databank, Wales (UK) from 1999 to 2015. Of data available on 3,765,744 individuals, a cohort who had ever been prescribed a PPI was developed (n = 183,968) for people aged 55 years and over and compared to non-PPI exposed individuals (131,110). Those with prior dementia, mild-cognitive-impairment or delirium codes were excluded. Confounding factors included comorbidities and/or drugs associated with them. Comorbidities might include head injury and some examples of medications include antidepressants, antiplatelets and anticoagulants. These commonly prescribed drugs were investigated as it was not feasible to explore all drugs in this study. The main outcome was a diagnosis of incident dementia. Cox proportional hazard regression modelling was used to calculate the Hazard ratio (HR) of developing dementia in PPI-exposed compared to unexposed individuals while controlling for potential confounders. The mean age of the PPI exposed individuals was 69.9 years and 39.8% male while the mean age of the unexposed individuals was 72.1 years and 41.1% male. The rate of PPI usage was 58.4% (183,968) and incident dementia rate was 11.8% (37,148/315,078). PPI use was associated with decreased dementia risk (HR: 0.67, 95% CI: 0.65 to 0.67, p<0.01).

CONCLUSIONS

This study, using large-scale, multi-centre health-data was unable to confirm an association between PPI use and increased dementia risk. Previously reported links may be associated with confounders of people using PPI's, such as increased risk of cardiovascular disease and/or depression and their associated medications which may be responsible for any increased risk of developing dementia.

Potential proton pump inhibitor-related adverse effects

Proton pump inhibitors (PPIs) are one of the most common medications taken by patients worldwide. PPIs are used to treat acid-related disorders, including gastroesophageal reflux disease, peptic ulcer disease, Helicobacter pylori infection, and nonsteroidal anti-inflammatory drug/stress ulceration. For some of these diseases, long-term treatment is necessary. With such prolonged use, concern and investigation into potential adverse effects has increased. In addition, data are available regarding potential anticancer effects of PPIs, especially regarding solid tumors. The aim of this review is to assess the literature on PPIs with regard to common concerns, such as drug-drug interactions, the intestinal microbiome, dementia and central nervous system disease, and osteoporosis, as well as to highlight potential negative and positive impacts of the drug in cancer.

Possible dementia risk of proton pump inhibitors and H2 receptor blockers use in the treatment of Helicobacter pylori: A meta-analysis study

INTRODUCTION

The risk of dementia when using proton-pump-inhibitors (PPIs) and H2-receptor-blockers as a treatment of Helicobacter-pylori have a lot of controversial-research with different results; however, no final recommendation was deduced from all these researches. A meta-analysis study was performed to evaluate the relationship between PPIs and H2-receptor-blockers use and dementia.

METHODS

Through a systematic literature search up to December-2019, 10-studies with 371951-subjects of them 71021Helicobacter-pylori-positive subjects using either PPIs or H2-receptor-blockers or both were identified reporting-relationships between PPIs and H2-receptor-blockers uses and dementia (10-studies contained PPIS, 4-contained H2-receptor-blockers). Odd-ratio (OR) with 95% confidence-intervals (CIs) was calculated comparing PPIs and H2-receptor-blockers users and to non-user subjects on the bases of dementia using the dichotomous-method with a random-effect-model.

RESULTS

No significant difference was found between PPIs-users or non-user (OR, 0.87; 95% CI, 0.62-1.22) or between H2-receptor blockers-users and non-users (OR, 1.21; 95% CI, 0.91-1.59) as a risk of dementia. The extent of increases in dementia with H2-receptor-blockers was higher than that with PPIs. The impact of PPIs and H2-receptor-blockers was similar in all populations.

CONCLUSIONS

Based on this meta-analysis, the contentious use of PPIs or H2-receptor-blockers may not have an independent-relationship to dementia. This suggests that using PPIs or H2-receptor-blockers is not related to dementia. However, we still have to recommend careful use of PPIs and H2-receptor-blockers when treating Helicobacter-pylori and sticking to the dose and length of treatment and not to extend it to avoid any possible risk.

Is it time to use real-world data from primary care in Alzheimer's disease?

BACKGROUND

The analysis of real-world data in clinical research is rising, but its use to study dementia subtypes has been hardly addressed. We hypothesized that real-world data might be a powerful tool to update AD epidemiology at a lower cost than face-to-face studies, to estimate the prevalence and incidence rates of AD in Catalonia (Southern Europe), and to assess the adequacy of real-world data routinely collected in primary care settings for epidemiological research on AD.

METHODS

We obtained data from the System for the Development of Research in Primary Care (SIDIAP) database, which contains anonymized information of > 80% of the Catalan population. We estimated crude and standardized incidence rates and prevalences (95% confidence intervals (CI)) of AD in people aged at least 65 years living in Catalonia in 2016.

RESULTS

Age- and sex-standardized prevalence and incidence rate of AD were 3.1% (95%CI 2.7-3.6) and 4.2 per 1000 person-years (95%CI 3.8-4.6), respectively. Prevalence and incidence were higher in women and in the oldest people.

CONCLUSIONS

Our incidence and prevalence estimations were slightly lower than the recent face-to-face studies conducted in Spain and higher than other analyses of electronic health data from other European populations. Real-world data routinely collected in primary care settings could be a powerful tool to study the epidemiology of AD.

No Association Linking Short-Term Proton Pump Inhibitor Use to Dementia: Systematic Review and Meta-analysis of Observational Studies

INTRODUCTION

Long-term use of proton pump inhibitors (PPIs) has been associated with a wide variety of potentially serious adverse effects including a possible increased risk of dementia. Studies evaluating this association have reached divergent conclusions. We aimed to evaluate this proposed association further and to assess the quality of the evidence in its support.

METHODS

We searched MEDLINE, EMBASE, ISI Web of Science, and Cochrane databases for studies examining a link between PPI use and dementia, up to February 2019. Studies reporting summary results as hazard ratio (HR) or odds ratio (OR) were pooled using the DerSimonian and Laird random-effects model for meta-analyses. Methodological quality of individual observational studies was assessed using the Newcastle-Ottawa scale and the overall quality of evidence rated as per the GRADE approach.

RESULTS

We identified and included 11 observational studies comprising 642,949 subjects; 64% were women. Most studies were short-term ranging from 5 to 10 years. There were 158,954 PPI users and 483,995 nonusers. For studies summarizing data as adjusted HR, pooled HR for all causes of dementia was 1.10 (0.88-1.37); for Alzheimer dementia only, it was 1.06 (0.72-1.55). For studies summarizing data as adjusted OR, pooled OR for all causes of dementia was 1.03 (0.84-1.25) and for Alzheimer dementia only 0.96 (0.82-1.11). Per Newcastle-Ottawa scale assessment, 10 studies were of high quality and 1 was of moderate quality. By applying GRADE methodology, quality of evidence for both outcomes was very low.

DISCUSSION

We found no evidence to support the proposed association between PPI use and an increased risk of dementia. PPI use among patients who have a valid indication for it, should not be curtailed because of concerns about dementia risk.

Benzodiazepines, z-Hypnotics, and Risk of Dementia: Special Considerations of Half-Lives and Concomitant Use

The utilization of benzodiazepines (BZDs) and z-hypnotics has substantially increased with the aging of the population, but the risk of BZDs and z-hypnotics in the development of dementia remains a strong concern. This cohort study aimed to evaluate the risk of BZDs and z-hypnotics for subsequent dementia development with a special consideration of their half-lives and the concomitant use of these medications. People aged 65 years and older who were newly prescribed oral BZDs or z-hypnotics between 2003 and 2012 were identified from Taiwan's National Health Insurance Research Database. All BZDs were categorized as long-acting drugs (≥ 20 h) or short-acting drugs (< 20 h) for further comparisons, and data were collected on a quarterly basis, starting on the first date of drug prescription and ending on the date of death, occurrence of dementia, or end of the follow-up period (December 31, 2012), whichever came first. All dementia events except vascular dementia occurring during the follow-up period were identified. Among 260,502 eligible subjects, short-acting BZDs and z-hypnotics users were at greater risk of dementia than long-acting users [adjusted odds ratio (95% confidence interval) in short-acting BZD users, 1.98 (1.89-2.07); z-hypnotic users, 1.79 (1.68-1.91); and long-acting BZD users, 1.47 (1.37-1.58)]. In addition, subjects concomitantly using 2 or more BZDs or z-hypnotics had a higher risk of dementia than those who used 1 of these drugs (4.79 (3.95-5.81)). The use of BZDs and z-hypnotics was strongly associated with the risk of dementia development, especially the short-acting BZDs, z-hypnotics, and concomitant use of multiple agents. These findings deserve further interventional studies for clarification.

No association between proton pump inhibitor use and risk of dementia: Evidence from a meta-analysis

BACKGROUND AND AIM

A growing body of literature suggests the association between dementia risk and proton pump inhibitor (PPI) use. Therefore, we aimed to investigate the association between PPI use and dementia risk.

METHODS

An extensive literature search was performed in PubMed, Embase, and Cochrane till March 31, 2019. All the studies (cohort and case-control) assessing the association between PPI use and dementia risk were eligible for inclusion. Articles were selected based on the screening of title and abstract, data were extracted, and risk of bias was assessed using Newcastle-Ottawa scale. The primary outcome was pooled risk of dementia among PPI user as compared with non-PPI user. Secondary outcomes include dementia risk based on subgroups. Statistical analysis was performed using review manager software.

RESULTS

Twelve studies (eight cohort and four case-control) were found to be eligible for inclusion. Majority of the studies were of high quality. Dementia was diagnosed based on International Classification of Diseases 9/10 codes in majority of the included studies. PPI use was not associated with the dementia risk, with a pooled relative risk (RR) of 1.05 (95% confidence interval [CI]: 0.96-1.15), P = 0.31. Subgroup analysis based on study design (cohort: P = 0.14; case-control: P = 0.14), sex (RR 1.25 [95% CI: 0.97-1.60], P = 0.08), histamine 2 receptor antagonist blockers (P = 0.93), and Alzheimer's disease (RR 1.00 [95% CI: 0.91-1.09], P = 0.93) revealed no significant association between PPI use and dementia risk.

CONCLUSION

We found no significant association between PPI use and the risk of dementia or Alzheimer's disease.

Proton pump inhibitors use and dementia risk: a meta-analysis of cohort studies

PURPOSE

The aim of this study was to explore the relationship between proton pump inhibitors use and the risk of dementia.

METHODS

A comprehensive literature search was conducted in English and Chinese databases from origination to December 2018. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated with a random-effects model. Subgroup analyses and sensitivity analyses were also conducted. Cochran's Q test and the I² statistic were used to evaluate the heterogeneity. Publication bias was assessed by Begg's test and Egger's test.

RESULTS

Six studies were included, which contained a total of 166,146 participants. The overall result demonstrated a significant increase in dementia risk with proton pump inhibitors use (HR = 1.29, 95% CI = 1.12-1.49). In subgroup analyses, a significant association was detected between proton pump inhibitors use and the risk of dementia in Europe (HR = 1.46, 95% CI = 1.23-1.73) and among participants aged ≥ 65 years (HR = 1.39, 95% CI = 1.17-1.65). For the factor follow-up time ≥ 5 years, the pooled HR was 1.28 (95% CI = 1.12-1.46), demonstrating a 1.28-fold increase in the risk of dementia among proton pump inhibitors users. In the case of regional impact, participants from Europe showed an overall pooled HR estimate of 1.46 (95% CI = 1.23-1.73). There was no evidence of publication bias.

CONCLUSIONS

The overall result of this meta-analysis supports the hypothesis that proton pump inhibitors increase the risk of dementia. Furthermore, high-quality cohort studies are needed to confirm these findings.

Drug interactions with dementia-related pathophysiological pathways worsen or prevent dementia

Many risk factors are known to induce or precipitate dementia. Drugs acting via different mechanisms can modulate cognitive performance and exert either beneficial or deleterious effects on cognition through functional or neuropathological mechanisms. This review discusses the association between several classes of drugs and cognitive impairment and dementia risk. These drugs can be divided into drugs targeting CNS disorders (e.g., anticholinergic drugs, antiepileptics, antipsychotics, benzodiazepines, and opioids) and drugs targeting non‐CNS disorders (e.g., antidiabetics, antihypertensives, proton pump inhibitors, and statins). Furthermore, we sought to highlight the pharmacological mechanisms underlying their possible detrimental or beneficial effects on cognition. Anticholinergic and antiepileptic drugs were excluded from this review because their effects on cognition are well known. Studies investigating benzodiazepines have revealed an increased risk of dementia. Conclusions on dementia risk or cognitive impairment regarding opioids and antipsychotic drugs are difficult to draw. These different classes appear to impair cognition not by a single clear mechanism of action specific to each class but by several relatively interdependent and interconnected mechanisms (e.g., impaired neurotransmission, neuroinflammation, neuronal death, oxidative stress, or interactions with dementia‐related pathways). The dementia risk initially associated with the use of proton pump inhibitors might have been overestimated. In contrast, statins, antihypertensive medications, and antidiabetics could potentially decrease the risk of dementia and cognitive impairment by acting in ways opposite to the mechanisms cited above.

Linked Articles

This article is part of a themed section on Therapeutics for Dementia and Alzheimer's Disease: New Directions for Precision Medicine. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.18/issuetoc

Proton pump inhibitor use does not increase dementia and Alzheimer's disease risk: An updated meta-analysis of published studies involving 642305 patients

Recent studies have indicated an increased risk of dementia and Alzheimer’s disease (AD) among people who consume proton pump inhibitors (PPIs), but the results of those studies are inconsistent. This meta-analysis aimed to explore the correction risk of dementia and AD among PPI users. The literature search for relevant studies was conducted in PubMed, Web of Science, EMBase and ScienceDirect. Pooled hazard ratio (HR) and 95% confidence intervals (CIs) were used to assess the relationship between the PPIs and risk of dementia and AD. Ten independent studies that involved 642305 participants were included in this meta-analysis. PPI users were unassociated with dementia (HR = 1.04, 95% CI 0.92–1.15; I² = 95.6%, p < 0.001) and AD (HR = 0.96, 95% CI 0.83–1.09; I² = 80.7%, p <0 .001). No evidence of publication bias was detected by Begg’s and Egger’s test. Sensitivity analyses showed no important differences in the estimates of effects. The current evidence indicates that PPI use does not increase dementia and AD risk. The remarkable heterogeneity among the studies warrants a further review of our findings.