The association between sodium-glucose cotransporter 2 inhibitors and incident dementia: A nationwide population-based longitudinal cohort study

The Promising Potency of Sodium–Glucose Cotransporter 2 Inhibitors in the Prevention of and as Treatment for Cognitive Impairment Among Type 2 Diabetes Patients

Type 2 diabetes mellitus (T2DM), accounting for the majority of diabetes mellitus prevalence, is associated with an increased risk of cognition decline and deterioration of cognition function in diabetic patients. The sodium–glucose cotransporter 2 (SGLT2), located in the renal proximal tubule, plays a role in urine glucose reabsorption. SGLT2 inhibitors (SGLT2i), have shown potential benefits beyond cardiac and renal improvement in preventing and treating cognitive impairment (CI), including mild cognitive impairment, Alzheimer’s disease and vascular dementia in T2DM patients. Studies suggest that SGLT2i may ameliorate diabetic CI through metabolism pathways, inflammation, oxidative stress, neurotrophic factors and AChE inhibition. Clinical trials and meta-analyses have reported significant and insignificant results. Given their vascular effects, SGLT2i may offer unique protection against vascular CI. This review compiles mechanisms and clinical evidence, emphasizing the need for future analysis, evaluation, trials and meta-analyses to verify and recommend optimal SGLT2i selection and dosage for specific patients.

New Insights into the Role of SGLT-2 Inhibitors in the Prevention of Dementia

Diabetes mellitus (DM) is a chronic disease associated with numerous complications, including cardiovascular diseases, nephropathy, and neuropathy. Sodium-glucose cotransporter 2 (SGLT-2) inhibitors, a class of novel antidiabetic agents, have demonstrated promising therapeutic effects beyond glycemic control, with potential benefits extending to the cardiovascular and renal systems. Recently, research has increasingly focused on exploring the potential role of SGLT-2 inhibitors in preventing dementia. The aim of this review is to summarize the current research suggesting that SGLT-2 inhibitors, such as empagliflozin and dapagliflozin, may have neuroprotective effects that reduce dementia risk and improve cognitive function in type 2 diabetes patients. These benefits are likely due to better glycemic control, reduced oxidative stress, and less advanced glycation end-product (AGE) formation, all linked to neurodegeneration. Despite these promising findings, existing studies are limited by small sample sizes and short follow-up durations, which may not adequately capture long-term outcomes. To establish more robust evidence, larger-scale, long-term randomized controlled trials (RCTs) involving diverse populations are needed. These studies should involve diverse populations and focus on understanding the mechanisms behind the neuroprotective effects. Addressing these limitations will provide clearer guidelines for using SGLT-2 inhibitors in dementia prevention and management. This will help improve therapeutic strategies for cognitive health in diabetic patients.

Association of sodium-glucose cotransporter 2 inhibitors with risk of incident dementia and all-cause mortality in older patients with type 2 diabetes: A retrospective cohort study using the TriNetX US collaborative networks

BACKGROUND

Limited evidence exists to support any specific medication over others to prevent dementia in older patients with type 2 diabetes (T2D). We investigated whether treatment with sodium-glucose cotransporter 2 (SGLT-2) inhibitors is associated with a lower risk of incident dementia and all-cause mortality, relative to dipeptidyl peptidase-4 (DPP-4) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RA).

METHODS

In this retrospective, active-comparator cohort study, we used data from the TriNetX electronic health records network. Our primary cohort comprised patients with T2D aged ≥50 years, registered between January 2012 and December 2022. Patients with a history of dementia were excluded. We used Kaplan-Meier survival analysis to estimate the incidence of dementia and all-cause mortality in our cohort after they had used glucose-lowering drugs for at least 12 months. Propensity score matching was performed to balance the SGLT-2 inhibitor, DPP-4 inhibitor and GLP-1 RA cohorts. Subgroup analyses for sex and age were also conducted.

RESULTS

Our first cohort comprised 193 948 patients treated with metformin and SGLT-2 inhibitors and an equal number of patients treated with metformin and DPP-4 inhibitors. In this cohort, the risk of dementia and all-cause mortality was lower in patients treated with SGLT-2 inhibitors than in those treated with DPP-4 inhibitors (hazard ratio [HR]: 0.62, 95% confidence interval [CI]: 0.59-0.65, for dementia; HR: 0.54, 95% CI: 0.52-0.56, for all-cause mortality). Our second cohort comprised 165 566 patients treated with metformin and SGLT-2 inhibitors and an equal number of patients treated with metformin and GLP-1 RAs. In this cohort, the risk of dementia and all-cause mortality was lower in those treated with SGLT-2 inhibitors than in those treated with GLP-1 RAs (HR: 0.92, 95% CI: 0.87-0.98, for dementia; HR: 0.88, 95% CI: 0.85-0.91, for all-cause mortality).

CONCLUSIONS

The use of SGLT-2 inhibitor was associated with a lower risk of incident dementia and all-cause mortality in older adults with T2D compared to DPP-4 inhibitor and GLP-1 RA.

Sodium-glucose cotransporter-2 inhibitors versus dipeptidyl peptidase IV inhibitors and risk of dementia among patients with type 2 diabetes and comorbid mental disorders: A population-based cohort study

AIM

To evaluate whether the use of sodium-glucose cotransporter-2 (SGLT2) inhibitors which have shown potential neuroprotective effects, is associated with lower risk of dementia in patients with type 2 diabetes (T2D) and comorbid mental disorders, who are considerably more susceptible to dementia.

METHODS

Using the nationwide healthcare data of South Korea between 2010 and 2022, we conducted a retrospective cohort study among patients with T2D and comorbid mental disorders initiating SGLT2 inhibitors versus active comparator (Dipeptidyl Peptidase IV (DPP4) inhibitors). Hazard ratios (HRs) and rate differences (RDs) per 1000 person-years of incident dementia were estimated after weighting by propensity score fine stratification method.

RESULTS

Over a 4.8-year median follow-up, SGLT2 inhibitors were associated with a 12 % lower risk of dementia compared with DPP4 inhibitors (11.31 vs. 12.86 events per 1000 person years; HR 0.88, 95 % CI 0.84 to 0.92; RD -1.55, -2.13 to -0.97). The results were consistent when stratified by age, sex, individual component, severe mental disorders, presence of insulin, history of cardiovascular disease, or history of hypertension.

CONCLUSIONS

SGLT2 inhibitors versus DPP4 inhibitors were associated with a lower risk of incident dementia in patients with T2D and comorbid mental disorders. Further randomized controlled trials are required to confirm our findings.

SGLT2 Inhibitor Use and Risk of Dementia and Parkinson Disease Among Patients With Type 2 Diabetes

BACKGROUND AND OBJECTIVES

Despite the mechanistic potential of sodium-glucose cotransporter 2 inhibitor (SGLT2i) to improve neurologic outcomes, the efficacy of SGLT2i in neurodegenerative disorders among patients with type 2 diabetes is not well established. This population-based cohort study aimed to investigate the association of SGLT2i use with risks of incident dementia and Parkinson disease (PD) in patients with type 2 diabetes.

METHODS

This was a retrospective examination of data from a cohort of 1,348,362 participants with type 2 diabetes (≥40 years), who started antidiabetic drugs from 2014 to 2019, evaluated using the Korean National Health Insurance Service Database. Propensity score matching (1:1; SGLT2i to other oral antidiabetic drugs [OADs]) produced a cohort of 358,862 participants. Primary outcomes were the individual incidence of Alzheimer disease (AD), vascular dementia (VaD), and PD. Secondary outcomes were all-cause dementia (AD, VaD, and other dementia) and a composite of all-cause dementia and PD. Cox proportional hazards models were used to investigate the association between SGLT2i use and the risks of dementia and PD.

RESULTS

From the 358,862 participants analyzed (mean [SD] age, 57.8 [9.6] years; 58.0% male), 6,837 incident dementia or PD events occurred. Regarding the individual endpoints, SGLT2i use was associated with reduced risks of AD (adjusted hazard ratio [aHR] 0.81, 95% CI 0.76-0.87), VaD (aHR 0.69, 95% CI 0.60-0.78), and PD (aHR 0.80, 95% CI 0.69-0.91) with a 6-month drug use lag period. In addition, use of SGLT2i was associated with a 21% lower risk of all-cause dementia (aHR 0.79, 95% CI 0.69-0.90) and a 22% lower risk of all-cause dementia and PD than use of other OADs (aHR 0.78, 95% CI 0.73-0.83). The association between the use of SGLT2i and the lowered risk of these neurodegenerative disorders was not affected by sex, Charlson Comorbidity Index, diabetic complications, comorbidities, and medications. Sensitivity analysis further adjusting for bioclinical variables from health screening tests, including blood pressure, glucose, lipid profiles, and kidney function, yielded generally consistent results.

DISCUSSION

In this nationwide population-based study, SGLT2i use significantly reduced the risks of neurodegenerative disorders in patients with type 2 diabetes independent of various factors including comorbidities and bioclinical parameters.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that SGLT2 antidiabetic drugs decrease the risk of dementia and PD in people with diabetes.

Risk of dementia after initiation of sodium-glucose cotransporter-2 inhibitors versus dipeptidyl peptidase-4 inhibitors in adults aged 40-69 years with type 2 diabetes: population based cohort study

OBJECTIVE

To compare the risk of dementia associated with sodium-glucose cotransporter-2 (SGLT-2) inhibitors versus dipeptidyl peptidase-4 (DPP-4) inhibitors in adults aged 40-69 years with type 2 diabetes.

DESIGN

Population based cohort study.

SETTING

Korean National Health Insurance Service data, 2013-21.

PARTICIPANTS

110 885 propensity score matched pairs of adults with type 2 diabetes aged 40-69 years who were initiators of either an SGLT-2 inhibitor or a DPP-4 inhibitor.

MAIN OUTCOME MEASURES

The primary outcome was new onset dementia. Secondary outcomes were dementia requiring drug treatment and individual types of dementia, including Alzheimer's disease and vascular dementia. Control outcomes were genital infections (positive), and osteoarthritis related clinical encounters and cataract surgery (negative). Hazard ratios and 95% confidence intervals (CIs) were estimated using Cox models. Follow-up time stratified analyses (>2 years and ≤2 years) and subgroup analyses by age, sex, concomitant use of metformin, and baseline cardiovascular risk were performed.

RESULTS

110 885 propensity score matched pairs of initiators of an SGLT-2 inhibitor or a DPP-4 inhibitor were followed-up for a mean 670 (standard deviation 650) days, generating 1172 people with newly diagnosed dementia: incidence rate 0.22 per 100 person years in initiators of SGLT-2 inhibitors and 0.35 per 100 person years in initiators of DPP-4 inhibitors, with hazard ratios of 0.65 (95% CI 0.58 to 0.73) for dementia, 0.54 (0.46 to 0.63) for dementia requiring drugs, 0.61 (0.53 to 0.69) for Alzheimer's disease, and 0.48 (0.33 to 0.70) for vascular dementia. The hazard ratios for the control outcomes were 2.67 (2.57 to 2.77) for genital infections, 0.97 (0.95 to 0.98) for osteoarthritis related encounters, and 0.92 (0.89 to 0.96) for cataract surgery. When calibrated for residual confounding measured by cataract surgery, the hazard ratio for dementia was 0.70 (0.62 to 0.80). The association was greater for more than two years of treatment (hazard ratio of dementia 0.57, 95% CI 0.46 to 0.70) than for two years or less (0.52, 0.41 to 0.66) and persisted across subgroups.

CONCLUSION

SGLT-2 inhibitors might prevent dementia, providing greater benefits with longer treatment. As this study was observational and therefore prone to residual confounding and informative censoring, the effect size could have been overestimated. Randomised controlled trials are needed to confirm these findings.

Insulin Resistance, a Risk Factor for Alzheimer's Disease: Pathological Mechanisms and a New Proposal for a Preventive Therapeutic Approach

Peripheral insulin resistance (IR) is a well-documented, independent risk factor for the development of type 2 diabetes, cardiovascular disease, cancer and cellular senescence. Recently, the brain has also been identified as an insulin-responsive region, where insulin acts as regulator of the brain metabolism. Despite the clear link between IR and the brain, the exact mechanisms underlying this relationship remain unclear. Therapeutic intervention in patients showing symptoms of neurodegenerative diseases has produced little or no results. It has been demonstrated that insulin resistance plays a significant role in the pathogenesis of neurodegenerative diseases, particularly cognitive decline. Peripheral and brain IR may represent a modifiable state that could be used to prevent major brain disorders. In this review, we will analyse the scientific literature supporting IR as a risk factor for Alzheimer's disease and suggest some therapeutic strategies to provide a new proposal for the prevention of brain IR and its consequences.

Impact of Sodium Glucose Cotransporter 2 Inhibitors (SGLT2i) Therapy on Dementia and Cognitive Decline

Dementia is an age-related syndrome characterized by the progressive deterioration of cognition and capacity for independent living. Diabetes is often associated with cognitive decline and shares similar pathophysiological mechanisms with dementia, such as systemic inflammation, oxidative stress, insulin resistance, and advanced glycation end-products formation. Therefore, adequate diabetes management may reduce the risk of cognitive decline, especially in patients with other comorbidities and risk factors. The sodium glucose cotransporter inhibitors (SGLT2i) regulate renal glucose reabsorption by blocking the SGLT2 cotransporters located in the proximal tubules, causing glycosuria and intraglomerular pressure reduction. Their use helps to lower blood pressure by modifying sodium and water homeostasis; these drugs are also commonly used in the treatment of heart failure and chronic kidney disease, while recently, a potential neuroprotective role in the central nervous system has been suggested. The aim of our scoping review is to analyze current evidence about the potential neuroprotective effects of SGLT2i in adult patients. We performed a scoping literature review to evaluate the effect of SGLT2i on dementia, mild cognitive impairment (MCI) and Alzheimer's disease incidence and progression. The screening process was performed through different searches on PubMed and EMBASE, evaluating original works published up to January 2024. In conclusion, the use of SGLT2i could be associated with a neuroprotective effect in patients with diabetes, reducing the incidence or the progression of MCI and dementia. Further prospective studies are needed to validate this hypothesis and to evaluate the effectiveness of this class of drugs in normal glycemic profile patients.

Assessment of sodium-glucose cotransporter 2 inhibitors (SGLT2i) and other antidiabetic agents in Alzheimer's disease: A population-based study

The lack of effective treatments for dementia has led to explore the potential of antidiabetic agents as a possible approach. This cross-sectional and population-based study aimed to investigate the relationship between each antidiabetic drug and their defined daily doses (DDDs) and the use of anti-Alzheimer's disease (AD) drugs in order to establish new possible hypotheses about the role of antidiabetic drugs in AD. For that purpose, a database containing information on medications prescribed to 233183 patients aged 50 years or older between 2018 and 2020 was used. DDDs were calculated according to the ATC/DDD index 2023. Statistical analyses, with logistic regression, were carried out to assess antidiabetic and anti-AD drugs consumption. A total of 91836 patients who were prescribed at least one antihypertensive, antidiabetic, or lipid-modifying agent were included in the study; specifically, 29260 patients were prescribed antidiabetic medication. Among the antidiabetic agents, glucagon-like peptide-1 analogs (GLP-1) DDDs were likely to have a positive association with anti-AD drugs in people aged between 70 and 80 years. Additionally, sodium-glucose cotransporter 2 inhibitors (SGLT2i) were prone to have a positive association with anti-AD drug usage across almost every age. However, insulin usage was associated with an increased usage of anti-AD agents. In conclusion, there is evidence suggesting a correlation between certain antidiabetic agents and dementia. Specifically, GLP-1 and SGLT2i might be associated with lower odds of anti-AD drugs usage, while insulins might be linked to higher odds of using anti-AD drugs.

Comparing regional brain uptake of incretin receptor agonists after intranasal delivery in CD-1 mice and the APP/PS1 mouse model of Alzheimer's disease

Targeting brain insulin resistance (BIR) has become an attractive alternative to traditional therapeutic treatments for Alzheimer's disease (AD). Incretin receptor agonists (IRAs), targeting either or both of the glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors, have proven to reverse BIR and improve cognition in mouse models of AD. We previously showed that many, but not all, IRAs can cross the blood-brain barrier (BBB) after intravenous (IV) delivery. Here we determined if widespread brain uptake of IRAs could be achieved by circumventing the BBB using intranasal (IN) delivery, which has the added advantage of minimizing adverse gastrointestinal effects of systemically delivered IRAs. Of the 5 radiolabeled IRAs tested (exenatide, dulaglutide, semaglutide, DA4-JC, and DA5-CH) in CD-1 mice, exenatide, dulaglutide, and DA4-JC were successfully distributed throughout the brain following IN delivery. We observed significant sex differences in uptake for DA4-JC. Dulaglutide and DA4-JC exhibited high uptake by the hippocampus and multiple neocortical areas. We further tested and found the presence of AD-associated Aβ pathology minimally affected uptake of dulaglutide and DA4-JC. Of the 5 tested IRAs, dulaglutide and DA4-JC are best capable of accessing brain regions most vulnerable in AD (neocortex and hippocampus) after IN administration. Future studies will need to be performed to determine if IN IRA delivery can reduce BIR in AD or animal models of that disorder.

Gluco-regulation & type 2 diabetes: entrenched misconceptions updated to new governing principles for gold standard management

Our understanding of type 2 diabetes (T2D) has evolved dramatically. Advances have upended entrenched dogmas pertaining to the onset and progression of T2D, beliefs that have prevailed from the early era of diabetes research-and continue to populate our medical textbooks and continuing medical education materials. This review article highlights key insights that lend new governing principles for gold standard management of T2D. From the historical context upon which old beliefs arose to new findings, this article outlines evidence and perspectives on beta cell function, the underlying defects in glucoregulation, the remediable nature of T2D, and, the rationale supporting the shift to complication-centric prescribing. Practical approaches translate this rectified understanding of T2D into strategies that fill gaps in current management practices of prediabetes through late type 2 diabetes.

Sodium-glucose cotransporter-2 inhibitors and their potential role in dementia onset and cognitive function in patients with diabetes mellitus: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to determine the association between the use of sodium-glucose cotransporter 2 (SGLT-2) inhibitors and dementia onset as well as cognitive function in patients with diabetes mellitus. We comprehensively searched the MEDLINE, Embase, and CENTRAL databases to select relevant studies published up to August 2023. The use of SGLT-2 inhibitors significantly lowers dementia risk compared to SGLT-2i non-users (Hazard ratio: 0.68, 95 % CI: 0.50-0.92). Furthermore, our findings indicated a positive effect of SGLT-2 inhibitor use on cognitive function score improvement, as demonstrated by the standardized mean difference of 0.88 (95 % CI: 0.32-1.44), particularly among populations with mild cognitive impairment or dementia. This systematic review and meta-analysis indicate a potential role of SGLT-2 inhibitors in reducing the risk of dementia in patients with diabetes mellitus. These findings underscore the need for well-controlled large clinical trials and future research in this field.

Pharmacological interventions in human aging

Pharmacological interventions are emerging as potential avenues of alleviating age-related disease. However, the knowledge of ongoing clinical trials as they relate to aging and pharmacological interventions is dispersed across a variety of mediums. In this review we summarize 136 age-related clinical trials that have been completed or are ongoing. Furthermore, we establish a database that describe the trials (AgingDB, www.agingdb.com) keeping track of the previous and ongoing clinical trials, alongside their outcomes. The aim of this review and database is to give people the ability to easily query for their trial of interest and stay up to date on the latest results. In sum, herein we give an overview of the current pharmacological strategies that have been applied to target human aging.

Risk of Dementia in Patients with Diabetes Using Sodium-Glucose Transporter 2 Inhibitors (SGLT2i): A Systematic Review, Meta-Analysis, and Meta-Regression

INTRODUCTION

Dementia is quite prevalent and among the leading causes of death worldwide. According to earlier research, diabetes may increase the possibility of developing dementia. However, the association between antidiabetic agents and dementia is not yet clear. This investigation examines the association between the use of sodium-glucose transporter 2 inhibitors (SGLT2i) and the risk of dementia in patients with diabetes.

METHODS

Up to April 18, 2023, four databases-Europe PMC, Medline, Scopus, and Cochrane Library-were searched for relevant literature. We included all studies that examine dementia risk in adults with diabetes who use SGLT2i. Random-effect models were used to compute the outcomes in this investigation, producing pooled odds ratios (OR) with 95% confidence intervals (CI).

RESULTS

Pooled data from seven observational studies revealed that SGLT2i use was linked to a lower risk of dementia in people with diabetes (OR 0.45, 95% CI 0.34-0.61; p < 0.00001, I2 = 97%). The reduction in the risk of dementia due to SGLT2i's neuroprotective effect was only significantly affected by dyslipidemia (p = 0.0004), but not by sample size (p = 0.2954), study duration (p = 0.0908), age (p = 0.0805), sex (p = 0.5058), hypertension (p = 0.0609), cardiovascular disease (p = 0.1619), or stroke (p = 0.2734).

CONCLUSIONS

According to this research, taking SGLT2i reduces the incidence of dementia in people with diabetes by having a beneficial neuroprotective impact. Randomized controlled trials (RCTs) are still required in order to verify the findings of our research.

The impact of sodium-glucose co-transporter-2 inhibitors on dementia and cardiovascular events in diabetic patients with atrial fibrillation

AIMS

The effectiveness of sodium-glucose co-transporter-2 inhibitors (SGLT2i) on incident dementia in patients with diabetes and atrial fibrillation (AF) remains unknown. This study aimed to investigate the association between SGLT2i and the risk of incident dementia in diabetic patients with AF, and to explore the interactions with oral anticoagulants or dipeptidyl peptidase-4 inhibitors (DPP4i).

MATERIALS AND METHODS

We conducted a cohort study using Taiwan's National Health Insurance Research Database. Patients with diabetes and AFwithout a prior history of established cardiovascular diseases, were identified. Using propensity score matching, 810 patients receiving SGLT2i were matched with 1620 patients not receiving SGLT2i. The primary outcome was incident dementia, and secondary outcomes included composite cardiovascular events and mortality.

RESULTS

After up to 5 years of follow-up, SGLT2i use was associated with a significantly lower risk of incident dementia (hazard: 0.71, 95% confidence interval: 0.51-0.98), particularly vascular dementia (HR: 0.44, 95% CI: 0.24-0.82). SGLT2i was related to reduced risks of AF-related hospitalisation (HR: 0.72, 95% CI: 0.56-0.93), stroke (HR: 0.75, 95% CI: 0.60-0.94), and all-cause death (HR: 0.33, 95% CI: 0.24-0.44). The protective effects were consistent irrespective of the concurrent use of non-vitamin K antagonist oral anticoagulants (NOACs) or DPP4i.

CONCLUSIONS

In diabetic patients with AF, SGLT2i was associated with reduced risks of incident dementia, AF-related hospitalisation, stroke, and all-cause death. The protective effects were independent of either concurrent use of NOACs or DPP4i.

Diabetes, antidiabetic medications and risk of dementia: A systematic umbrella review and meta-analysis

AIMS

The objective of this umbrella review and meta-analysis was to evaluate the effect of diabetes on risk of dementia, as well as the mitigating effect of antidiabetic treatments.

MATERIALS AND METHODS

We conducted a systematic umbrella review on diabetes and its treatment, and a meta-analysis focusing on treatment. We searched MEDLINE/PubMed, Embase, PsycINFO, CINAHL and the Cochrane Library for systematic reviews and meta-analyses assessing the risk of cognitive decline/dementia in individuals with diabetes until 2 July 2023. We conducted random-effects meta-analyses to obtain risk ratios and 95% confidence intervals estimating the association of metformin, thiazolidinediones, pioglitazone, dipeptidyl peptidase-4 inhibitors, α-glucosidase inhibitors, meglitinides, insulin, sulphonylureas, glucagon-like peptide-1 receptor agonists (GLP1RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2is) with risk of dementia from cohort/case-control studies. The subgroups analysed included country and world region. Risk of bias was assessed with the AMSTAR tool and Newcastle-Ottawa Scale.

RESULTS

We included 100 reviews and 27 cohort/case-control studies (N = 3 046 661). Metformin, thiazolidinediones, pioglitazone, GLP1RAs and SGLT2is were associated with significant reduction in risk of dementia. When studies examining metformin were divided by country, the only significant effect was for the United States. Moreover, the effect of metformin was significant in Western but not Eastern populations. No significant effect was observed for dipeptidyl peptidase-4 inhibitors, α-glucosidase inhibitors, or insulin, while meglitinides and sulphonylureas were associated with increased risk.

CONCLUSIONS

Metformin, thiazolidinediones, pioglitazone, GLP1RAs and SGLT2is were associated with reduced risk of dementia. More longitudinal studies aimed at determining their relative benefit in different populations should be conducted.

GLP-1 receptor agonists, SGLT2 inhibitors and noncardiovascular mortality in type 2 diabetes: Insights from a meta-analysis

OBJECTIVE

Type-2 diabetes (T2D) poses a higher risk of noncardiovascular mortality in addition to the burden of cardiovascular mortality. The well-established cardiovascular benefits of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2i) could solely explain their apparent effects on all-cause mortality in T2D. The present meta-analysis aims to pool their effects on noncardiovascular mortality in T2D and summarize the recent evidence on plausible pathways mediating these effects.

METHODS

PubMed, Embase, Web of Science, and clinical trial registries were searched for randomized controlled trials (RCTs) with ≥1-year duration in adults with T2D reporting both cardiovascular and all-cause mortality in treatment versus placebo arms (PROSPERO: CRD42022337559). Noncardiovascular mortality was calculated by subtracting cardiovascular mortality events from all-cause mortality and risk ratios (RRs) were calculated. Random-effects meta-analysis was done. GRADE framework was used to assess evidence quality.

RESULTS

We identified 17 eligible RCTs pooling data retrieved from 109,892 patients. Randomization to GLP-1 RA treatment versus placebo was associated with reduced noncardiovascular mortality (RR = 0.90; 95%CI: 0.81-0.99; I2 = 0 %; p < 0.05), consistent with their effects on cardiovascular mortality (RR = 0.88; 95%CI: 0.81-0.95; I2 = 0 %; p < 0.01) in T2D. Compared to placebo, SGLT2i significantly reduced noncardiovascular mortality (RR = 0.90; 95%CI: 0.82-0.99; I2 = 0 %; p < 0.05) along with cardiovascular mortality (RR = 0.84; 95%CI: 0.77-0.92; I2 = 28 %; p < 0.001). Subgroup analysis showed no significant effects of heart failure or renal function on treatment benefits of SGLT2i on noncardiovascular mortality (p value > 0.2 for subgroup differences).

CONCLUSION

The impact of GLP-1RAs and SGLT2i on mortality in people with T2D extends beyond their cardiovascular benefits.

Anti-diabetics and the Prevention of Dementia: A Systematic Review

Type 2 diabetes mellitus (T2DM) is a worldwide epidemic that is only increasing as the years progress, and as of 2019, affecting over 37 million. T2DM is a chronic condition caused by reduced insulin secretion and increased insulin resistance. Due to insulin not operating at optimal conditions, blood glucose rises and remains high, thus disturbing metabolic hemostasis. Many complications can arise from T2DM, such as coronary vascular disease, kidney damage, eye damage, and, quite significantly, dementia. It is theorized that dementia from T2DM stems from the fact that the brain is susceptible to hyperglycemic conditions, which are promoted by the increase in insulin resistance of target cells in the central nervous system. This directly affects cognitive processes and memory, which correlates to decreased temporal and front lobes volume. The risk of diabetic complications can be minimized with therapeutic interventions such as oral-antidiabetic (OAD) agents and insulin. Several OADs are on the market, but the first-line agent is metformin, a biguanide that decreases glucose production and increases insulin sensitivity. This paper aims to determine if currently prescribed OADs can help slow cognitive decline and reduce the risk and incidence of dementia as a complication of T2DM. Studies found that, for the most part, all OADs except sulfonylureas (SU) significantly slowed the decline of cognitive function and reduced the risk and incidence of dementia. SU's were shown to increase the risk of dementia in most studies. Of all the OADs, thiazolidinediones may be the most beneficial drug class for reducing the risk of dementia in T2DM patients. Future research should focus on whether early intervention with specific classes of OADs can not only improve glycemic control, leading to decreased hyperglycemia but also prevent the build-up of damaged brain tissue and help to reduce the risk and incidence of dementia in patients with T2DM.

Comparison on cognitive outcomes of antidiabetic agents for type 2 diabetes: A systematic review and network meta-analysis

We aimed to summarise current evidence on different antidiabetic drugs to delay cognitive impairment, including mild cognitive impairment, dementia, Alzheimer's disease (AD) and vascular dementia, among subjects with type 2 diabetes mellitus (T2DM). Medline, Cochrane and Embase databases were searched from inception to 31 July 2022. Two investigators independently reviewed and screened trials comparing antidiabetic drugs with no antidiabetic drugs, placebo, or other active antidiabetic drugs on cognitive outcomes in T2DM. Data were analysed using meta-analysis and network meta-analysis. Twenty-seven studies met the inclusion criteria, including 3 randomised controlled trials, 19 cohort studies and 5 case-control studies. Compared with non-user, SGLT-2i (OR 0.41 [95% CI 0.22-0.76]), GLP-1RA (OR 0.34 [95% CI 0.14-0.85]), thiazolidinedione (OR 0.60 [95% CI 0.51-0.69]), and DPP-4i (OR 0.78 [95% CI 0.61-0.99]) users had a decreased risk of dementia, whereas sulfonylurea (OR 1.43 [95% CI 1.11-1.82]) increased dementia risk. Network meta-analysis showed that SGLT-2i was most likely to rank best (SUCRA = 94.4%), GLP-1 RA second best (SUCRA = 92.7%), thiazolidinedione third best (SUCRA = 74.7%) and DPP-4i fourth best (SUCRA = 54.9%), while sulfonylurea second worst (SUCRA = 20.0%) for decreasing dementia outcomes, by synthesising evidence from direct and indirect comparisons of multiple intervention. Evidence suggests the effects of SGLT-2i ≈ GLP-1 RAs > thiazolidinedione > DPP-4i for delaying cognitive impairment, dementia and AD outcomes, whereas sulfonylurea was associated with the highest risk. These findings provide evidence for evaluating the optional treatment for clinical practice. PROSPERO REGISTRATION: Registration no. CRD42022347280.

The role of Neurochemicals, Stress Hormones and Immune System in the Positive Feedback Loops between Diabetes, Obesity and Depression

Type 2 diabetes mellitus (T2DM) and depression are significant public health and socioeconomic issues. They commonly co-occur, with T2DM occurring in 11.3% of the US population, while depression has a prevalence of about 9%, with higher rates among youths. Approximately 31% of patients with T2DM suffer from depressive symptoms, with 11.4% having major depressive disorders, which is twice as high as the prevalence of depression in patients without T2DM. Additionally, over 80% of people with T2DM are overweight or obese. This review describes how T2DM and depression can enhance one another, using the same molecular pathways, by synergistically altering the brain's structure and function and reducing the reward obtained from eating. In this article, we reviewed the evidence that eating, especially high-caloric foods, stimulates the limbic system, initiating Reward Deficiency Syndrome. Analogous to other addictive behaviors, neurochemical changes in those with depression and/or T2DM are thought to cause individuals to increase their food intake to obtain the same reward leading to binge eating, weight gain and obesity. Treating the symptoms of T2DM, such as lowering HbA1c, without addressing the underlying pathways has little chance of eliminating the disease. Targeting the immune system, stress circuit, melatonin, and other alterations may be more effective.

Antidiabetic agents as a novel treatment for Alzheimer's and Parkinson's disease

Therapeutic strategies for neurodegenerative disorders have commonly targeted individual aspects of the disease pathogenesis to little success. Neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD), are characterized by several pathological features. In AD and PD, there is an abnormal accumulation of toxic proteins, increased inflammation, decreased synaptic function, neuronal loss, increased astrocyte activation, and perhaps a state of insulin resistance. Epidemiological evidence has revealed a link between AD/PD and type 2 diabetes mellitus, with these disorders sharing some pathological commonalities. Such a link has opened up a promising avenue for repurposing antidiabetic agents in the treatment of neurodegenerative disorders. A successful therapeutic strategy for AD/PD would likely require a single or several agents which target the separate pathological processes in the disease. Targeting cerebral insulin signalling produces numerous neuroprotective effects in preclinical AD/PD brain models. Clinical trials have shown the promise of approved diabetic compounds in improving motor symptoms of PD and preventing neurodegenerative decline, with numerous further phase II trials and phase III trials underway in AD and PD populations. Alongside insulin signalling, targeting incretin receptors in the brain represents one of the most promising strategies for repurposing currently available agents for the treatment of AD/PD. Most notably, glucagon-like-peptide-1 (GLP-1) receptor agonists have displayed impressive clinical potential in preclinical and early clinical studies. In AD the GLP-1 receptor agonist, liraglutide, has been demonstrated to improve cerebral glucose metabolism and functional connectivity in small-scale pilot trials. Whilst in PD, the GLP-1 receptor agonist exenatide is effective in restoring motor function and cognition. Targeting brain incretin receptors reduces inflammation, inhibits apoptosis, prevents toxic protein aggregation, enhances long-term potentiation and autophagy as well as restores dysfunctional insulin signalling. Support is also increasing for the use of additional approved diabetic treatments, including intranasal insulin, metformin hydrochloride, peroxisome proliferator-activated nuclear receptor γ agonists, amylin analogs, and protein tyrosine phosphatase 1B inhibitors which are in the investigation for deployment in PD and AD treatment. As such, we provide a comprehensive review of several promising anti-diabetic agents for the treatment of AD and PD.

Repositioning of Anti-Diabetic Drugs against Dementia: Insight from Molecular Perspectives to Clinical Trials

Insulin resistance as a hallmark of type 2 DM (T2DM) plays a role in dementia by promoting pathological lesions or enhancing the vulnerability of the brain. Numerous studies related to insulin/insulin-like growth factor 1 (IGF-1) signaling are linked with various types of dementia. Brain insulin resistance in dementia is linked to disturbances in Aβ production and clearance, Tau hyperphosphorylation, microglial activation causing increased neuroinflammation, and the breakdown of tight junctions in the blood-brain barrier (BBB). These mechanisms have been studied primarily in Alzheimer's disease (AD), but research on other forms of dementia like vascular dementia (VaD), Lewy body dementia (LBD), and frontotemporal dementia (FTD) has also explored overlapping mechanisms. Researchers are currently trying to repurpose anti-diabetic drugs to treat dementia, which are dominated by insulin sensitizers and insulin substrates. Although it seems promising and feasible, none of the trials have succeeded in ameliorating cognitive decline in late-onset dementia. We highlight the possibility of repositioning anti-diabetic drugs as a strategy for dementia therapy by reflecting on current and previous clinical trials. We also describe the molecular perspectives of various types of dementia through the insulin/IGF-1 signaling pathway.

Molecular and neural roles of sodium-glucose cotransporter 2 inhibitors in alleviating neurocognitive impairment in diabetic mice

Diabetes causes a variety of molecular changes in the brain, making it a real risk factor for the development of cognitive dysfunction. Complex pathogenesis and clinical heterogeneity of cognitive impairment makes the efficacy of current drugs limited. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) gained our attention as drugs with potential beneficial effects on the CNS. In the present study, these drugs ameliorated the cognitive impairment associated with diabetes. Moreover, we verified whether SGLT2i can mediate the degradation of amyloid precursor protein (APP) and modulation of gene expression (Bdnf, Snca, App) involved in the control of neuronal proliferation and memory. The results of our research proved the participation of SGLT2i in the multifactorial process of neuroprotection. SGLT2i attenuate the neurocognitive impairment through the restoration of neurotrophin levels, modulation of neuroinflammatory signaling, and gene expression of Snca, Bdnf, and App in the brain of diabetic mice. The targeting of the above-mentioned genes is currently seen as one of the most promising and developed therapeutic strategies for diseases associated with cognitive dysfunction. The results of this work could form the basis of a future administration of SGLT2i in diabetics with neurocognitive impairment.

Efficacy and safety profile of SGLT2 inhibitors in the elderly: How is the benefit/risk balance?

Type 2 diabetes mellitus (T2DM) is a highly prevalent health condition in the aging population. Older adults with T2DM have higher risks of cardiovascular disease, heart failure (long underestimated) and premature death than those without diabetes. Sodium-glucose cotransporter 2 inhibitors (SGLT2is) have proven their ability to improve cardiovascular prognosis and reduce the risk of hospitalization for heart failure (hHF). However, several adverse events have been reported, whose incidence and severity might be increased in the elderly population. The aims of this comprehensive review were to analyze the benefit-risk ratio of SGLT2i therapy in older patients with T2DM by collecting data from (i) large prospective placebo-controlled cardiovascular outcome trials (including those dedicated to heart failure), using both original publications and dedicated post-hoc analyses across different age groups and (ii) observational cohort studies, describing the effects of SGLT2is versus other glucose-lowering agents on cardiovascular outcomes and hHF in elderly patients or these effects in different age groups. Overall, consistent results showed a similar relative risk reduction in cardiovascular mortality and hHF with SGLT2is independently of age. The absolute risk reduction may be greater in elderly because of a higher background risk in older versus younger patients. Similarly, the safety profile of SGLT2is appeared comparable in older versus younger patients. In conclusion, the benefit/risk balance favors the use of SGLT2is in older patients at risk of cardiovascular disease and/or heart failure. Caution may be required in very old frail patients, especially those exposed to an increased risk of volume depletion.

Clinical pharmacology of antidiabetic drugs: What can be expected of their use?

The pharmacotherapy of type 2 diabetes mellitus (T2DM) has markedly evolved in the last two decades. Classical antidiabetic agents (sulphonylureas, metformin, insulin) are now in competition with new glucose-lowering medications. Alpha-glucosidase inhibitors and thiazolidinediones (glitazones) were not able to replace older agents, because of insufficient efficacy and/or poor tolerability/safety. In contrast, incretin-based therapies, both dipeptidyl peptidase-4 inhibitors (DPP-4is or gliptins, oral agents) and glucagon-like peptide-1 receptor agonists (GLP-1RAs, subcutaneous injections) are a major breakthrough in the management of T2DM. Because they are not associated with hypoglycaemia and weight gain, DPP-4is tend to replace sulphonylureas as add-on to metformin while GLP-1RAs tend to replace basal insulin therapy after failure of oral therapies. Furthermore, placebo-controlled cardiovascular outcome trials demonstrated neutrality for DPP-4is, but cardiovascular protection for GLP-1RAs in patients with T2DM at high cardiovascular risk. More recently sodium-glucose cotransporter 2 inhibitors (SGLT2is or gliflozins, oral agents) also showed cardiovascular protection, especially a reduction in hospitalization for heart failure, as well as a renal protection in patients with and without T2DM, at high cardiovascular risk, with established heart failure and/or with chronic kidney disease. Thus, GLP-1RAs and SGLT2is are now considered as preferred drugs in T2DM patients with or at high risk of atherosclerotic cardiovascular disease whereas SGLT2is are more specifically recommended in patients with or at risk of heart failure and renal (albuminuric) disease. The management of T2DM is moving from a glucocentric approach to a broader strategy focusing on all risk factors, including overweight/obesity, and to an organ-disease targeted personalized approach.

Association of Sodium-Glucose Cotransporter 2 Inhibitors With Time to Dementia: A Population-Based Cohort Study

OBJECTIVE

Type 2 diabetes (T2D) increases dementia risk, but clear evidence to recommend interventions that can mitigate that risk remains lacking. This population-based retrospective cohort study aimed to determine whether new use of sodium-glucose cotransporter 2 (SGLT2) inhibitors compared with dipeptidyl peptidase 4 (DPP-4) inhibitors was associated with lower dementia risk.

RESEARCH DESIGN AND METHODS

Ontario residents aged ≥66 years who were new users of an SGLT2 inhibitor or a DPP-4 inhibitor from 1 July 2016 to 31 March 2021 entered the cohort. Incident dementia was identified using a validated algorithm for Alzheimer's disease and related dementias. Propensity score-weighted Cox proportional hazards models were used to obtain adjusted hazard ratios (aHR) and CIs for time to incident dementia. To address reverse causality and disease latency, the observation window started at 1-year lag time from cohort entry. The primary analysis followed intention-to-treat exposure definition, and a secondary as-treated analysis was performed.

RESULTS

Among 106,903 individuals, SGLT2 inhibitors compared with DPP-4 inhibitors were associated with lower risk of dementia (14.2/1,000 person-years; aHR 0.80 [95% CI 0.71-0.89]) over a mean follow-up of 2.80 years from cohort entry. When stratified by different SGLT2 inhibitors, dapagliflozin exhibited the lowest risk (aHR 0.67 [95% CI 0.53-0.84]), followed by empagliflozin (aHR 0.78 [95% CI 0.69-0.89]), whereas canagliflozin showed no association (aHR 0.96 [95% CI 0.80-1.16]). The as-treated analysis observed a larger association (aHR 0.66 [95% CI 0.57-0.76]) than the intention-to-treat analysis.

CONCLUSIONS

SGLT2 inhibitors showed an association with lower dementia risk in older people with T2D. Randomized controlled trials are warranted.