Effects of SGLT2 inhibitors on fractures and bone mineral density in type 2 diabetes: An updated meta-analysis

The effects of type 1 and type 2 diabetes mellitus on bone health in chronic kidney disease

Fracture is an under-recognized but common complication of diabetes mellitus, with an incidence approaching twofold in type 2 diabetes mellitus (T2DM) and up to sevenfold in type 1 diabetes mellitus (T1DM) compared with that in the general population. Both T1DM and T2DM induce chronic hyperglycaemia, leading to the accumulation of advanced glycosylation end products that affect osteoblast function, increased collagen crosslinking and a senescence phenotype promoting inflammation. Together with an increased incidence of microvascular disease and an increased risk of vitamin D deficiency, these factors reduce bone quality, thereby increasing bone fragility. In T1DM, reduced anabolic stimuli as well as the presence of autoimmune conditions might also contribute to reduced bone mass and increased fragility. Diabetes mellitus is the most common cause of kidney failure, and fracture risk is exacerbated when chronic kidney disease (CKD)-related mineral and bone disorders are superimposed on diabetic changes. Microvascular pathology, cortical thinning and trabecular deterioration are particularly prominent in patients with T1DM and CKD, who suffer more fragility fractures than do other patients with CKD. This Review explores the pathophysiology of bone fragility in patients with diabetes mellitus and CKD and discusses techniques to predict fracture and pharmacotherapy that might reduce fracture risk.

Is the Impact of Sodium-Glucose Co-Transporter 2 (SGLT2) Inhibitors on Bone Metabolism and Fracture Incidence a Class or Drug Effect? A Narrative Review

Background/Objectives: Type 2 diabetes mellitus (T2DM) has a growing prevalence, even in developed countries. Because of the increase in life expectancy, the number of older people with T2DM is also increasing. The management and handling of these patients is challenging due to its co-morbidities. Aim: In the present study, we reviewed the literature in order to investigate the impact of sodium-glucose co-transporter 2 inhibitors (SGLT-2 inhibitors) on bone metabolism and fracture incidence. Methods: We searched the literature using the databases of PubMed, CENTRAL and Cochrane Central Register of Controlled Trials up to December 2024. Results: There is a controversial position in the literature concerning the effects of SGLT2 inhibitors when administered in T2DM, with respect to bone metabolism and bone fracture incidence. Multiple studies suggest the SGLT2 inhibitors have a disadvantageous effect on bone metabolism and fracture incidence, while several others suggest a beneficial effect. Conclusions: Patients with type 2 diabetes mellitus are at high risk of alterations in their bone metabolism. SGLT2 inhibitors are a novel class with pleiotropic effects in many organs, such as the kidneys and heart, although their effect on bone metabolism and fracture incidence is still unclear. Until we have more clinical data, all caregivers (medical and nursing staff) should be aware of possible bone fractures in patients receiving this class of agents.

Dapagliflozin Improves High-Fat Diet-Induced Cognitive Impairment in Female Mice

BACKGROUND

High fat consumption is a known risk factor for the development of type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD). Sodium-glucose cotransporter 2 inhibitors (SGLT2is) have been found to possess anti-inflammatory and neuroprotective properties. However, the cognitive effects and mechanisms of SGLT2is on female mice fed with a high-fat diet remain unknown.

OBJECTIVE

This study aimed to investigate the impacts of dapagliflozin on metabolism, cognition, neuroinflammation, insulin resistance, and microglial activation in female mice fed a HFD.

METHODS

Dapagliflozin (1 mg/kg) was administered to HFD-fed mice for 24 weeks. Body weight, glucose tolerance, and insulin resistance were assessed. Additionally, all mice were subjected to the Morris water maze (MWM) and one-trial Y-maze tests. The levels of metabolic hormones and cytokines were analyzed using ELISA kits. The levels of phosphorylated tau (p-tau) protein in the hippocampus were measured. Microglia, insulin receptors, NLRP3, and IL-1β in the hippocampus of mice were evaluated by immunofluorescence or immunohistochemical staining.

RESULTS

As anticipated, dapagliflozin improved insulin resistance and glucose metabolism and reduced cognitive impairment in female mice fed with a HFD. In the hippocampus, dapagliflozin alleviated microglial activation yet did not reduce the secretion of inflammatory chemokines. Furthermore, it increased the expression of insulin receptor in the hippocampus of HFD-fed mice and decreased the expression of p-tau.

CONCLUSIONS

Our results provide a foundation for the clinical application of SGLT2is as an adjuvant to slow down the progression of central degenerative diseases related to metabolic disorders, such as AD.

Causal inference in health and disease: a review of the principles and applications of Mendelian randomization

Mendelian randomization (MR) is a genetic epidemiological technique that uses genetic variation to infer causal relationships between modifiable exposures and outcome variables. Conventional observational epidemiological studies are subject to bias from a range of sources; MR analyses can offer an advantage in that they are less prone to bias as they use genetic variants inherited at conception as "instrumental variables", which are proxies of an exposure. However, as with all research tools, MR studies must be carefully designed to yield valuable insights into causal relationships between exposures and outcomes, and to avoid biased or misleading results that undermine the validity of the causal inferences drawn from the study. In this review, we outline Mendel's laws of inheritance, the assumptions and principles that underlie MR, MR study designs and methods, and how MR analyses can be applied and reported. Using the example of serum phosphate concentrations on liability to kidney stone disease we illustrate how MR estimates may be visualized and, finally, we contextualize MR in bone and mineral research including exemplifying how this technique could be employed to inform clinical studies and future guidelines concerning BMD and fracture risk. This review provides a framework to enhance understanding of how MR may be used to triangulate evidence and progress research in bone and mineral metabolism as we strive to infer causal effects in health and disease.

Dapagliflozin cardiovascular effects on end-stage kidney disease (DARE-ESKD-2) trial: rationale and design

BACKGROUND

Dapagliflozin prevents myocardial dysfunction in chronic kidney disease patients regardless of residual kidney function. We hypothesized that this effect is extensible also to patients on dialysis.

RESEARCH DESIGN AND METHODS

The DARE-ESKD-2 is an ongoing, single-center, open-label randomized clinical trial designed to determine the effects of adding dapagliflozin to standard treatment on myocardial function and structure. Eligible patients were adults on a regular dialysis scheme for more than 3 months. Pregnancy, liver failure, allergy to the investigational drug, and prior use of SGLT2i were exclusion criteria. Participants were randomized in a 1:1 ratio to dapagliflozin or standard treatment groups for 24-weeks. The primary goal is to compare the change in NT-proBNP levels between study arms, and secondary goals include comparing the between-group difference in left ventricle global longitudinal strain, indexed mass, ejection fraction, and E/e` ratio, and on symptoms scale and 6-minute walk test distance. An exploratory analysis will evaluate changes in body composition and bone densitometry.

RESULTS

The trial has finished the enrollment of 80 patients, who are currently being followed-up.

CONCLUSIONS

This trial will provide novel data on myocardial effects of SGLT2i in dialysis recipients. Results from this study may provide evidence to support SGLT2i use in ESKD.

A multicentre, double-blind, placebo-controlled, randomized, parallel comparison, phase 3 trial to evaluate the efficacy and safety of pioglitazone add-on therapy in type 2 diabetic patients treated with metformin and dapagliflozin

AIM

To investigate the efficacy and safety of pioglitazone compared to placebo when added to metformin plus dapagliflozin, a sodium-glucose cotransporter-2 (SGLT2) inhibitor, for patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

In a multicentre study, with a randomized, double-blind, placebo-controlled design, 249 Korean patients with T2DM suboptimally managed on metformin and dapagliflozin were assigned to receive either pioglitazone (15 mg daily) or placebo for 24 weeks, followed by a 24-week pioglitazone extension. Primary outcomes included changes in glycated haemoglobin (HbA1c), with secondary outcomes assessing insulin resistance, adiponectin levels, lipid profiles, liver enzymes, body weight and waist circumference.

RESULTS

Pioglitazone administration resulted in a significant reduction in HbA1c levels (from 7.80% ± 0.72% to 7.27% ± 0.82%) compared with placebo (from 7.79% ± 0.76% to 7.69% ± 0.86%, corrected mean difference: -0.42% ± 0.08%; p < 0.01) at 24 weeks. Additional benefits from pioglitazone treatment included enhanced insulin sensitivity, increased adiponectin levels, raised high-density lipoprotein cholesterol levels and reduced liver enzyme levels, resulting in improvement in nonalcoholic fatty liver disease liver fat score. Despite no serious adverse events in either group, pioglitazone therapy was modestly but significantly associated with weight gain and increased waist circumference.

CONCLUSIONS

Adjunctive pioglitazone treatment in T2DM inadequately controlled with metformin and dapagliflozin demonstrates considerable glycaemic improvement, metabolic benefits, and a low risk of hypoglycaemia. These advantages must be weighed against the potential for weight gain and increased waist circumference.

4. Comprehensive Medical Evaluation and Assessment of Comorbidities: Standards of Care in Diabetes-2024

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, an interprofessional expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Drug Therapies for Diabetes

The treatment of type 2 diabetes (T2D) necessitates a multifaceted approach that combines behavioral and pharmacological interventions to mitigate complications and sustain a high quality of life. Treatment encompasses the management of glucose levels, weight, cardiovascular risk factors, comorbidities, and associated complications through medication and lifestyle adjustments. Metformin, a standard in diabetes management, continues to serve as the primary, first-line oral treatment across all age groups due to its efficacy, versatility in combination therapy, and cost-effectiveness. Glucagon-like peptide-1 receptor agonists (GLP-1 RA) offer notable benefits for HbA1c and weight reduction, with significant cardiovascular benefits. Sodium-glucose cotransporter inhibitors (SGLT-2i) lower glucose levels independently of insulin while conferring notable benefits for cardiovascular, renal, and heart-failure outcomes. Combined therapies emphasizing early and sustained glycemic control are promising options for diabetes management. As insulin therapy remains pivotal, metformin and non-insulin agents such as GLP-1 RA and SGLT-2i offer compelling options. Notably, exciting novel treatments like the dual GLP-1/ glucose-dependent insulinotropic polypeptide (GIP) agonist show promise for substantially reducing glycated hemoglobin and body weight. This comprehensive review highlights the evolving landscape of pharmacotherapy in diabetes, the drugs currently available for treating diabetes, their effectiveness and efficacy, the impact on target organs, and side effects. This work also provides insights that can support the customization of treatment strategies.

SGLT2 Inhibitors' Cardiovascular Benefits in Individuals Without Diabetes, Heart Failure, and/or Chronic Kidney Disease: A Systematic Review

Despite the growing body of evidence regarding the beneficial cardiovascular effects of sodium-glucose cotransporter-2 (SGLT2) inhibitors, clinical data in individuals without diabetes, heart failure (HF), and/or chronic kidney disease (CKD) is limited. A systematic review of the literature was conducted in PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar, from database inception until May 4, 2023, to explore new evidence of SGLT2 inhibitors' cardiovascular benefits in individuals without diabetes, HF, and/or CKD. A total of 1156 individuals from 14 studies (13 randomized controlled trials and 1 nonrandomized study) were included. The results showed the benefits of SGLT2 inhibitors on blood pressure, weight, and body mass index in this population with an acceptable safety profile. The current evidence supports the potential role of SGLT2 inhibitors as primary prevention in individuals without diabetes, HF, and/or CKD. This review may shed light on the use of SGLT2 inhibitors in conditions such as stage A HF and metabolic syndrome. The literature trend is going toward uncovering SGLT2 inhibitors' role in stage B HF, different types of myocardial infarction, and cardiac arrhythmias.

Effect of SGLT2 inhibitors on fractures, BMD, and bone metabolism markers in patients with type 2 diabetes mellitus: a systematic review and meta-analysis

This meta-analysis aims to evaluate the impact of Sodium Glucose Transporter 2 (SGLT2) inhibitors on fractures, bone mineral density (BMD), and bone metabolism markers in type 2 diabetes mellitus (T2DM) patients. Pooled relative risk (RR) with 95% confidence interval (CI) assessed the relationship between SGLT2 inhibitors and fracture risk. Weighted mean difference (WMD) with 95% CI explored the correlation between SGLT2 inhibitors and BMD, as well as bone metabolism markers. A total of 20 randomised controlled trials (RCTs) involving 12,764 patients were analysed. No significant association emerged between SGLT2 inhibitor use and elevated fracture risk (pooled RR = 1.21, 95% CI [0.95, 1.54], I2 = 22%). Furthermore, SGLT2 inhibitors exhibited no substantial effects on BMD changes at the lumbar spine (WMD = -0.02, 95% CI [-0.38, 0.34]), femoral neck (WMD = 0.11, 95% CI [-0.28, 0.50]), total hip (WMD = -0.20, 95% CI [-0.41, 0.01]), and distal forearm (WMD = -0.20, 95% CI [-0.62, 0.22]). Similarly, no notable impact of SGLT2 inhibitors on bone metabolism markers, including CTX (WMD = 0.04, 95% CI [-0.02, 0.09]), P1NP (WMD = 1.06, 95% CI [-0.44, 2.57]), PTH (WMD = 0.34, 95% CI [-0.07, 0.75]), calcium (WMD = 0.01, 95% CI [-0.02, 0.04]), and phosphate (WMD = 2.37, 95% CI [-0.76, 5.49]). The findings suggest that the utilization of SGLT2 inhibitors is not significantly linked to an elevated risk of fractures in individuals with T2DM. However, further clinical investigations and extended follow-up periods are warranted to establish more conclusive determinations.

Effect of Antidiabetic Drugs on Bone Health in Patients with Normal Renal Function and in Chronic Kidney Disease (CKD): Insight into Clinical Challenges in the Treatment of Type 2 Diabetes

Among the metabolic changes occurring during the course of type 2 diabetes (T2DM) and diabetic kidney disease (DKD), impaired bone health with consequent increased fracture risk is one of the most complex and multifactorial complications. In subjects with diabetic kidney disease, skeletal abnormalities may develop as a consequence of both conditions. In the attempt to define a holistic approach to diabetes, potential effects of various classes of antidiabetic drugs on the skeleton should be considered in the setting of normal kidney function and in DKD. We reviewed the main evidence on these specific topics. Experimental studies reported potential beneficial and harmful effects on bone by different antidiabetics, with few data available in DKD. Clinical studies specifically designed to evaluate skeletal effects of antidiabetics have not been performed; notwithstanding, data gleaned from randomized controlled trials and intervention studies did not completely confirm observations made by basic research. In the aggregate, evidence from meta-analyses of these studies suggests potential positive effects on fracture risk by metformin and glucagon-like peptide-1 receptor agonists, neutral effects by dipeptidyl peptidase-4 inhibitors, sodium-glucose cotransporter-2 inhibitors, and sulfonylureas, and negative effects by insulin and thiazolidinediones. As no clinical recommendations on the management of antidiabetic drugs currently include fracture risk assessment among the main goal of therapy, we propose an integrated approach with the aim of defining a patient-centered management of diabetes in chronic kidney disease (CKD) and non-CKD patients. Future clinical evidence on the skeletal effects of antidiabetics will help in optimizing the approach to a personalized and more effective therapy of diabetes.

Evaluation of the Effect of Sodium-Glucose Cotransporter 2 Inhibition on Fracture Risk: Evidence From Mendelian Randomization and Genetic Association Study

This study aims to evaluate the causal effect of sodium-glucose cotransporter 2 (SGLT2) inhibition on bone mineral density (BMD), osteoporosis, and fracture risk using genetics. Two-sample Mendelian randomization (MR) analyses were performed utilizing two sets of genetic variants as instruments (six and two single-nucleotide polymorphisms [SNPs]) associated with SLC5A2 gene expression and glycated hemoglobin A1c levels. Summary statistics of BMD from the Genetic Factors for Osteoporosis consortium (BMD for total body, n = 66,628; femoral neck, n = 32,735; lumbar spine, n = 28,498; forearm, n = 8143) and osteoporosis (6303 cases, 325,717 controls) and 13 types of fracture (≤17,690 cases, ≤328,382 controls) data from the FinnGen study were obtained. One-sample MR and genetic association analyses were conducted in UK Biobank using the individual-level data of heel BMD (n = 256,286) and incident osteoporosis (13,677 cases, 430,262 controls) and fracture (25,806 cases, 407,081 controls). Using six SNPs as the instrument, genetically proxied SGLT2 inhibition showed little evidence of association with BMD of total body, femoral neck, lumbar spine, and forearm (all p ≥ 0.077). Similar results were observed using two SNPs as instruments. Little evidence was found for the SGLT2 inhibition effect on osteoporosis (all p ≥ 0.112) or any 11 major types of fracture (all p ≥ 0.094), except for a nominal significance for fracture of lower leg (p = 0.049) and shoulder and upper arm (p = 0.029). One-sample MR and genetic association analysis showed that both the weighted genetic risk scores constructed from the six and two SNPs were not causally associated with heel BMD, osteoporosis, and fracture (all p ≥ 0.387). Therefore, this study does not support an effect of genetically proxied SGLT2 inhibition on fracture risk. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Dapagliflozin cardiovascular effects on end-stage kidney disease (DARE-ESKD-2) trial: rationale and design

Purpose

Sodium glucose co-transporter 2 inhibitors (SGLT2i) remarkably reduced the incidence of hospitalization for heart failure and cardiovascular death of conservatively managed chronic kidney disease. We hypothesized that adding SGLT2i to standard treatment would yield cardiovascular benefits also in end-stage kidney disease (ESKD) individuals on dialysis.

Methods

The DARE-ESKD-2 Trial (NCT05685394) is an ongoing, single-center, open-label, controlled trial aimed at assessing the cardiovascular effects of dapagliflozin in ESKD on dialysis. Eligible patients are adults on renal replacement therapy for more than 3 prior to enrollment. Exclusion criteria encompass pregnancy, liver failure, and current use of a SGLT2i. After signing an informed consent form, participants are randomized 1:1 to either dapagliflozin 10mg PO plus standard treatment or standard treatment alone for 6 months. Echocardiogram, anthropometry, blood sample collection, 6-min walk test, gait speed, and Kansas City Cardiomyopathy Questionnaire (KCCQ), are performed at baseline and at study termination. Participants are contacted monthly during treatment for outcomes disclosure. The primary endpoint of our study is the between-groups differences in posttreatment changes in plasma levels of N-terminal pro-B natriuretic peptide. Secondary endpoints include the differences between groups in the changes of echocardiography measurements, cardiopulmonary tests performance, body composition. The incidence of safety endpoints will also be diligently compared between study arms.

Conclusion

The DARE-ESKD-2 trial will provide unprecedented data on the cardiovascular safety and efficacy of SGLT2i in ESKD individuals on dialysis. This study will pave the grounds for improving clinical outcomes of dialysis recipients.

An Increase in Plasma Sodium Levels Is Associated With an Increase in Osteoblast Function in Chronic SIAD

CONTEXT

Hyponatremia is associated with increased risk for osteoporosis. Preclinical studies in untreated hyponatremia suggest osteoclast upregulation, whereas a clinical study showed improved osteoblast function after hyponatremia normalization in hospitalized patients with syndrome of inappropriate antidiuresis (SIAD).

OBJECTIVE

This work aimed to investigate the effect of an increase in sodium on bone turnover, that is, the ratio of the osteoblast marker procollagen type 1 N-terminal propeptide (P1NP) to the osteoclast marker cross-linked C-terminal telopeptide of type 1 collagen (CTX), in outpatients with chronic SIAD.

METHODS

A predefined secondary analysis was conducted of the 2-month double-blind, crossover, placebo-controlled SANDx Trial (NCT03202667) performed from December 2017 to August 2021. Participants included 11 outpatients with chronic SIAD: 6 women, median age 73 years, who received a 4-week treatment with 25-mg empagliflozin or placebo. Main outcome measures included the relationship between the change in bone formation index (BFI), defined as P1NP/CTX, and the change in plasma sodium levels.

RESULTS

Changes in sodium were positively correlated with changes in BFI and P1NP (BFI: ρ=.55; P < .001; P1NP: ρ=.45; P = .004) but not with CTX (P = .184) and osteocalcin (P = .149). A sodium increase of 1 mmol/l was associated with an increase of 5.21 in BFI (95% CI, 1.41-9.00; P = .013) and with an increase of 1.48 µg/l in P1NP (95% CI, .26-2.62; P = .03). The effect of sodium change on bone markers was independent of the study medication empagliflozin.

CONCLUSION

An increase in plasma sodium levels in outpatients with chronic hyponatremia due to SIAD, even when mild, was associated with an increase in bone formation index (P1NP/CTX) triggered by an increase in P1NP, a surrogate marker of osteoblast function.

Management of Type 2 Diabetes in Frail Older Adults

Aging is one of the most important factors associated with the dramatic increase in the prevalence of type 2 diabetes mellitus (T2DM) globally. In addition to traditional micro- and macrovascular complications, diabetes mellitus (DM) in older adults is of great importance due to its independent relationship with frailty, which is defined as a decline in functional reserves and vulnerability to stressors. Frailty assessment enables the determination of biological age, thus predicting potential complications in older adults and identifying tailored treatment strategies. Although the latest guidelines have acknowledged the frailty concept and provided recommendations specific to this subgroup of older adults, frail older adults are particularly considered only as anorexic, malnourished people for whom relaxed treatment targets should be set. However, this approach bypasses other metabolic phenotypes in the context of diabetes and frailty. Recently, a spectrum of metabolic phenotypes in the context of frailty in DM was suggested, and the two edges of this spectrum were defined as "anorexic malnourished (AM)" and "sarcopenic obese (SO)." These two edges were suggested to require different strategies: Opposite to the AM phenotype requiring less stringent targets and de-intensification of treatments, tight blood glucose control with agents promoting weight loss was recommended in the SO group. Our suggestion is that, regardless of their phenotype, weight loss should not be the primary goal in DM management in older adults who are overweight or obese, because of the increased malnutrition prevalence in older adults suffering from DM compared with standard older adults. Furthermore, overweight older adults have been reported to have the lowest risk of mortality compared with other groups. On the other hand, obese older individuals may benefit from intensive lifestyle interventions including caloric restriction and regular exercise with the assurance of at least 1 g/kg/day high-quality protein intake. Besides metformin (MF), sodium-glucose cotransporter-2 inhibitors (SGLT-2i) or glucagon-like peptide-1 receptor agonists (GLP-1RA) should be considered in appropriate SO cases, due to high evidence of cardiorenal benefits. MF should be avoided in the AM phenotype due to their weight loss property. Although weight loss is not desired in AM phenotype, SGLT-2i may still be preferred with close follow-up in certain individuals demonstrating high cardiovascular disease (CVD) risk. Of note, SGLT-2i should be considered earlier in the diabetes treatment in both groups due to their multiple benefits, i.e., organ protective effects, the potential to reduce polypharmacy, and improve frailty status. The concept of different metabolic phenotypes in frail older adults with diabetes once again shows "one size fits all" cannot be applied in geriatric medicine, and a tailored, individualized approach should be adopted to get the highest benefit from treatments.

[Diagnosis and management of patients with diabetes and co-existing osteoporosis (Update 2023) : Common guideline of the Austrian Society for Bone and Mineral Research and the Austrian Diabetes Society]

Fragility fractures are increasingly recognized as a complication of both type 1 and type 2 diabetes, with fracture risk that increases with disease duration and poor glycemic control. The identification and management of fracture risk in these patients remains challenging. This manuscript explores the clinical characteristics of bone fragility in adults with diabetes and highlights recent studies that have evaluated areal bone mineral density (BMD), bone microstructure and material properties, biochemical markers, and fracture prediction algorithms (FRAX) in these patients. It further reviews the impact of diabetes drugs on bone tissue as well as the efficacy of osteoporosis treatments in this population. An algorithm for the identification and management of diabetic patients at increased fracture risk is proposed.

Repurposing SGLT-2 Inhibitors to Target Aging: Available Evidence and Molecular Mechanisms

Caloric restriction promotes longevity in multiple animal models. Compounds modulating nutrient-sensing pathways have been suggested to reproduce part of the beneficial effect of caloric restriction on aging. However, none of the commonly studied caloric restriction mimetics actually produce a decrease in calories. Sodium-glucose cotransporter 2 inhibitors (SGLT2-i) are a class of drugs which lower glucose by promoting its elimination through urine, thus inducing a net loss of calories. This effect promotes a metabolic shift at the systemic level, fostering ketones and fatty acids utilization as glucose-alternative substrates, and is accompanied by a modulation of major nutrient-sensing pathways held to drive aging, e.g., mTOR and the inflammasome, overall resembling major features of caloric restriction. In addition, preliminary experimental data suggest that SGLT-2i might also have intrinsic activities independent of their systemic effects, such as the inhibition of cellular senescence. Consistently, evidence from both preclinical and clinical studies have also suggested a marked ability of SGLT-2i to ameliorate low-grade inflammation in humans, a relevant driver of aging commonly referred to as inflammaging. Considering also the amount of data from clinical trials, observational studies, and meta-analyses suggesting a tangible effect on age-related outcomes, such as cardiovascular diseases, heart failure, kidney disease, and all-cause mortality also in patients without diabetes, here we propose a framework where at least part of the benefit provided by SGLT-2i is mediated by their ability to blunt the drivers of aging. To support this postulate, we synthesize available data relative to the effect of this class on: 1- animal models of healthspan and lifespan; 2- selected molecular pillars of aging in preclinical models; 3- biomarkers of aging and especially inflammaging in humans; and 4- COVID-19-related outcomes. The burden of evidence might prompt the design of studies testing the potential employment of this class as anti-aging drugs.

Unfavorable effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors on the skeletal system of nondiabetic rats

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of antidiabetic drugs, acting by inhibiting the reabsorption of glucose in the kidneys. They turned out to improve cardiovascular and renal outcomes not only in patients with type 2 diabetes but also in nondiabetic patients. At present, they are more and more widely used in patients without diabetes. Since there were concerns that SGLT2 inhibitors may increase fracture risk in diabetes, the aim of the study was to examine the effect of dapagliflozin and canagliflozin on the musculoskeletal system of nondiabetic, healthy rats. The experiments were carried out on mature female rats, divided into the control rats and rats treated with dapagliflozin (1.4 mg/kg p.o.) or canagliflozin (4.2 mg/kg p.o.) for 4 weeks. Serum bone turnover markers, skeletal muscle strength and mass, bone mass, density, histomorphometric parameters and mechanical properties were determined. Administration of the drugs did not affect the skeletal muscle mass and strength. There was no effect on serum bone turnover markers, and bone mass and composition. However, administration of both drugs resulted in disorders of cancellous bone microarchitecture and worsening of bone mechanical properties. In conclusion, both SGLT2 inhibitors unfavorably affected the skeletal system of healthy rats.

Use of sodium-glucose co-transporter 2 inhibitors, changes in body mass index and risk of fracture: A population-based cohort study

AIMS

Sodium-glucose co-transporter-2 (SGLT-2) inhibitor-induced weight loss might play a role in the debated elevated fracture risk with these agents. The aim of the current study was to investigate the association between SGLT-2 inhibitor use, changes in body mass index (BMI) and fracture risk.

METHODS

A retrospective cohort study was conducted using data from the UK Clinical Practice Research Datalink (CPRD) GOLD (2013-2018). The study population (N = 34,960) consisted of adults with diabetes initiating a sulphonylurea or SGLT-2 inhibitor. Cox proportional hazards models estimated hazard ratios (HRs) for major osteoporotic fracture with SGLT-2 inhibitor use versus sulphonylurea use, stratified by change in BMI, average daily dose and cumulative dose. Analyses were adjusted for age, sex, lifestyle variables, comorbidities, and concomitant drug use.

RESULTS

SGLT-2 inhibitor use was not associated with an increased fracture risk compared to sulphonylurea use (adjusted HR 1.19; 95% confidence interval (CI): 0.80-1.79). This finding remained consistent after stratification by BMI change. However, the highest cumulative dose category was associated with an increased fracture risk (adjusted HR: 2.10, 95 %CI: 1.11-3.99).

CONCLUSION

SGLT-2 inhibitor use was not associated with increased osteoporotic fracture risk, irrespective of change in BMI. However, a high cumulative dose could be an important risk factor.

Characteristics and molecular mechanisms through which SGLT2 inhibitors improve metabolic diseases: A mechanism review

Metabolic diseases, such as diabetes, gout and hyperlipidemia are global health challenges. Among them, diabetes has been extensively investigated. Type 2 diabetes mellitus (T2DM), which is characterized by hyperglycemia, is a complex metabolic disease that is associated with various metabolic disorders. The newly developed oral hypoglycemic agent, sodium-glucose cotransporter 2 (SGLT2) inhibitor, has been associated with glucose-lowering effects and it affects metabolism in various ways. However, the potential mechanisms of SGLT2 inhibitors in metabolic diseases have not fully reviewed. Many of the effects beyond glycemic control must be considered off-target effects. Therefore, we reviewed the effects of SGLT2 inhibitors on metabolic diseases such as obesity, hypertension, hyperlipidemia, hyperuricemia, fatty liver disease, insulin resistance, osteoporosis and fractures. Moreover, we elucidated their molecular mechanisms to provide a theoretical basis for metabolic disease treatment.

Clinical insights into management options for recurrent type 2 diabetes and cardiovascular risk after metabolic-bariatric surgery

AIMS

Long-term clinical trials evaluating the effects of metabolic-bariatric surgery (MBS) on type 2 diabetes (T2D) demonstrate that a significant proportion of patients either fail to achieve remission or experience T2D recurrence over time. Furthermore, patients with recurrent T2D might require reinstitution of pharmacotherapy to control comorbidities (hypertension, dyslipidemia). This paper reviews therapeutic options in patients with T2D relapse.

DATA SYNTHESIS

Although presently there is no recommended pharmacological strategy, the available data support GLP-1 analogues (GLP-1a) as the most suitable option to control hyperglycemia post-MBS. Beside their efficacy in lowering glycemia and body weight while preserving lean mass, GLP-1a exert cardiovascular/renal-protection and are also safe and well tolerated in surgical patients. In addition, the s.c. route of administration of these medications circumvents the problem of changes in oral drugs bioavailability following MBS. Of note, the available data refers to liraglutide and needs to be confirmed with weekly GLP-1a agents. Information regarding the impact of MBS on the pharmacokinetics of lipid lowering and anti-hypertensive drugs is scarce and inconclusive. The findings indicate that timing from intervention is particularly important because of adaptive intestinal mechanisms.

CONCLUSIONS

The recurrence of T2D following MBS is a clinically relevant issue. GLP-1a therapy represents the best option to improve glycemic and weight control with good tolerability. Long-term clinical trials will clarify the impact of these drugs on cardiovascular outcomes. A close monitoring of MBS patients is advised to guide drug dosage adjustments and ensure the control of cardiovascular risk factors.

Fracture Risk of Sodium-Glucose Cotransporter-2 Inhibitors in Chronic Kidney Disease

BACKGROUND AND OBJECTIVES

Sodium-glucose cotransporter-2 (SGLT2) inhibitors have been associated with a higher risk of skeletal fractures in some randomized, placebo-controlled trials. Secondary hyperparathyroidism and increased bone turnover (also common in CKD) may contribute to the observed fracture risk. We aimed to determine if SGLT2 inhibitor use associates with a higher risk of fractures compared with dipeptidyl peptidase-4 (DPP-4) inhibitors, which have no known association with fracture risk. We hypothesized that this risk, if present, would be greatest in patients with lower eGFR.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a population-based cohort study in Ontario, Canada between 2015 and 2019 using linked provincial administrative data to compare the incidence of fracture between new users of SGLT2 inhibitors and DPP-4 inhibitors. We used inverse probability of treatment weighting on the basis of propensity scores to balance the two groups of older adults (≥66 years of age) on indicators of baseline health. We compared the 180- and 365-day cumulative incidence rates of fracture between groups. Prespecified subgroup analyses were conducted by eGFR category (≥90, 60 to <90, 45 to <60, and 30 to <45 ml/min per 1.73 m²). Weighted hazard ratios were obtained using Cox proportional hazard regression.

RESULTS

After weighting, we identified a total of 38,994 new users of a SGLT2 inhibitor and 37,449 new users of a DPP-4 inhibitor and observed a total of 342 fractures at 180 days and 689 fractures at 365 days. The weighted 180- and 365-day risks of a fragility fracture did not significantly differ between new users of a SGLT2 inhibitor versus a DPP-4 inhibitor: weighted hazard ratio, 0.95 (95% confidence interval, 0.79 to 1.13) and weighted hazard ratio, 0.88 (95% confidence interval, 0.88 to 1.00), respectively. There was no observed interaction between fracture risk and eGFR category (P=0.53).

CONCLUSIONS

In this cohort study of older adults, starting a SGLT2 inhibitor versus DPP-4 inhibitor was not associated with a higher risk of skeletal fracture, regardless of eGFR.

Secondary Osteoporosis

Osteoporosis is a global public health problem, with fractures contributing to significant morbidity and mortality. Although postmenopausal osteoporosis is most common, up to 30% of postmenopausal women, > 50% of premenopausal women, and between 50% and 80% of men have secondary osteoporosis. Exclusion of secondary causes is important, as treatment of such patients often commences by treating the underlying condition. These are varied but often neglected, ranging from endocrine to chronic inflammatory and genetic conditions. General screening is recommended for all patients with osteoporosis, with advanced investigations reserved for premenopausal women and men aged < 50 years, for older patients in whom classical risk factors for osteoporosis are absent, and for all patients with the lowest bone mass (Z-score ≤ -2). The response of secondary osteoporosis to conventional anti-osteoporosis therapy may be inadequate if the underlying condition is unrecognized and untreated. Bone densitometry, using dual-energy x-ray absorptiometry, may underestimate fracture risk in some chronic diseases, including glucocorticoid-induced osteoporosis, type 2 diabetes, and obesity, and may overestimate fracture risk in others (eg, Turner syndrome). FRAX and trabecular bone score may provide additional information regarding fracture risk in secondary osteoporosis, but their use is limited to adults aged ≥ 40 years and ≥ 50 years, respectively. In addition, FRAX requires adjustment in some chronic conditions, such as glucocorticoid use, type 2 diabetes, and HIV. In most conditions, evidence for antiresorptive or anabolic therapy is limited to increases in bone mass. Current osteoporosis management guidelines also neglect secondary osteoporosis and these existing evidence gaps are discussed.

Risk Factors for Fracture in Patients with Coexisting Chronic Kidney Disease and Type 2 Diabetes: An Observational Analysis from the CREDENCE Trial

BACKGROUND

The fracture pathophysiology associated with type 2 diabetes and chronic kidney disease (CKD) is incompletely understood. We examined individual fracture predictors and prediction sets based on different pathophysiological hypotheses, testing whether any of the sets improved prediction beyond that based on traditional osteoporotic risk factors.

METHODS

Within the CREDENCE cohort with adjudicated fracture outcomes, we assessed the association of individual factors with fracture using Cox regression models. We used the Akaike information criteria (AIC) and Schwartz Bayes Criterion (SBC) to assess six separate variable sets based on hypothesized associations with fracture, namely, traditional osteoporosis, exploratory general population findings, cardiovascular risk, CKD-mineral and bone disorder, diabetic osteodystrophy, and an all-inclusive set containing all variables.

RESULTS

Fracture occurred in 135 (3.1%) participants over a median 2.35 [1.88-2.93] years. Independent fracture predictors were older age (hazard ratio [HR] 1.04, confidence interval [CI] 1.01-1.06), female sex (HR 2.49, CI 1.70-3.65), previous fracture (HR 2.30, CI 1.58-3.34), Asian race (HR 1.74, CI 1.09-2.78), vitamin D therapy requirement (HR 2.05, CI 1.31-3.21), HbA1c (HR 1.14, CI 1.00-1.32), prior cardiovascular event (HR 1.60, CI 1.10-2.33), and serum albumin (HR 0.41, CI 0.23-0.74) (lower albumin associated with greater risk). The goodness of fit of the various hypothesis sets was similar (AIC range 1870.92-1849.51, SBC range 1875.60-1948.04).

CONCLUSION

Independent predictors of fracture were identified in the CREDENCE participants with type 2 diabetes and CKD. Fracture prediction was not improved by models built on alternative pathophysiology hypotheses compared with traditional osteoporosis predictors.

The Extraglycemic Effect of SGLT-2is on Mineral and Bone Metabolism and Bone Fracture

Type 2 diabetes mellitus (T2DM) is a risk factor for osteoporosis. The effects of T2DM and anti-diabetic agents on bone and mineral metabolism have been observed. Sodium-glucose co-transporter 2 inhibitors (SGLT-2is) promote urinary glucose excretion, reduce blood glucose level, and improve the cardiovascular and diabetic nephropathy outcomes. In this review, we focused on the extraglycemic effect and physiological regulation of SGLT-2is on bone and mineral metabolism. SGLT-2is affect the bone turnover, microarchitecture, and bone strength indirectly. Clinical evidence of a meta-analysis showed that SGLT-2is might not increase the risk of bone fracture. The effect of SGLT-2is on bone fracture is controversial, and further investigation from a real-world study is needed. Based on its significant benefit on cardiovascular and chronic kidney disease (CKD) outcomes, SGLT-2is are an outstanding choice. Bone mineral density (BMD) and fracture risk evaluation should be considered for patients with a high risk of bone fracture.

New Therapeutic Horizons in Chronic Kidney Disease: The Role of SGLT2 Inhibitors in Clinical Practice

Chronic kidney disease (CKD) is a serious, progressive condition associated with significant patient morbidity. Hypertension control and use of renin-angiotensin system blockers are the cornerstones of treatment for CKD. However, even with these treatment strategies, many individuals will progress towards kidney failure. Recently, sodium-glucose cotransporter 2 (SGLT2) inhibitor clinical trials with primary renal endpoints have firmly established SGLT2 inhibition, in addition to standard of care, as an effective strategy to slow down the progression of CKD and reduce some of its associated complications. The emergence of this new clinical evidence supports the use of SGLT2 inhibitors in the management of CKD in people with and without diabetes. As licensing and guidelines for SGLT2 inhibitors are updated, there is a need to adapt CKD treatment pathways and for this class of drugs to be included as part of standard care for CKD management. In this article, we have used consensus opinion alongside the available evidence to provide support for the healthcare community involved in CKD management, regarding the role of SGLT2 inhibitors in clinical practice. By highlighting appropriate prescribing and practical considerations, we aim to encourage greater and safe use of SGLT2 inhibitors for people with CKD, both with and without diabetes.

Management of Hyperglycemia in Older Adults with Type 2 Diabetes

The increasing incidence of type 2 diabetes in the general population as well as enhanced life expectancy has resulted in a rapid rise in the prevalence of diabetes in the older population. Diabetes causes significant morbidity and impairs quality of life. Managing diabetes in older adults is a daunting task due to unique health and psychosocial challenges. Medical management is complicated by polypharmacy, cognitive impairment, urinary incontinence, injurious falls, and persistent pain. Health care providers now have several traditional and contemporary pharmacologic agents to manage diabetes. Avoidance of hypoglycemia is critical; however, evidence-based guidelines are lacking due to the paucity of clinical trials in older adults. For many in this population, maintaining independence is more important than adherence to published guidelines to prevent diabetes complications. The goal of diabetes care in older adults is to enhance the quality of life without subjecting these patients to intrusive and complicated interventions. Recent technological advancements such as continuous glucose monitoring systems can have crucial supplementary benefits in the geriatric population.

Update on the pathogenesis and treatment of skeletal fragility in type 2 diabetes mellitus

Fracture risk is increased in patients with type 2 diabetes mellitus (T2DM). In addition, these patients sustain fractures despite having higher levels of areal bone mineral density, as measured by dual-energy X-ray absorptiometry, than individuals without T2DM. Thus, additional factors such as alterations in bone quality could have important roles in mediating skeletal fragility in patients with T2DM. Although the pathogenesis of increased fracture risk in T2DM is multifactorial, impairments in bone material properties and increases in cortical porosity have emerged as two key skeletal abnormalities that contribute to skeletal fragility in patients with T2DM. In addition, indices of bone formation are uniformly reduced in patients with T2DM, with evidence from mouse studies published over the past few years linking this abnormality to accelerated skeletal ageing, specifically cellular senescence. In this Review, we highlight the latest advances in our understanding of the mechanisms of skeletal fragility in patients with T2DM and suggest potential novel therapeutic approaches to address this problem.

Efficacy / safety balance of DPP-4 inhibitors versus SGLT2 inhibitors in elderly patients with type 2 diabetes

Dipeptidyl peptidase-4 inhibitors (DPP-4is) and sodium-glucose cotransporter type 2 inhibitors (SGLT2is) offer new options for the oral management of type 2 diabetes mellitus (T2DM), with the advantage in the elderly population to be devoid of a high risk of hypoglycaemia. SGLT2is have also shown benefits regarding cardiovascular (heart failure) and renal protection, including in patients with T2DM aged ≥ 65 years while DPP-4is have only proved cardiovascular and renal safety without superiority compared with placebo. The glucose-lowering efficacy of the two pharmacological classes is almost similar including in older patients with T2DM. However, the tolerance and safety profile may be highly different and overall more favourable with DPP-4is than with SGLT2is. Some adverse events have been reported with SGLT2is which may be more prevalent or severe in older patients than in younger patients. The present comprehensive review focuses on the benefit/risk balance in the elderly population with T2DM by comparing the profile of DPP-4is and SGLT2is regarding the following potential issues: metabolic disorders (hypoglycaemia and diabetic ketoacidosis); cardiac and vascular issues (atheromatous cardiovascular disease, heart failure, volume reduction hypotension, and lower limb amputations); renal endpoints including acute renal injury; risk of infections; digestive disorders; bone and skin adverse events; and cancer risk. Both DPP-4is and SGLT2is have their own advantages and disadvantages. Personalised treatment is recommended based upon the efficacy/safety profile of each drug class and individual patient characteristics that may be markedly different among the heterogeneous population of older individuals with T2DM.

A Role for SGLT-2 Inhibitors in Treating Non-diabetic Chronic Kidney Disease

In recent years, inhibitors of the sodium-glucose co-transporter 2 (SGLT2 inhibitors) have been shown to have significant protective effects on the kidney and the cardiovascular system in patients with diabetes. This effect is also manifested in chronic kidney disease (CKD) patients and is minimally due to improved glycaemic control. Starting from these positive findings, SGLT2 inhibitors have also been tested in patients with non-diabetic CKD or heart failure with reduced ejection fraction. Recently, the DAPA-CKD trial showed a significantly lower risk of CKD progression or death from renal or cardiovascular causes in a mixed population of patients with diabetic and non-diabetic CKD receiving dapagliflozin in comparison with placebo. In patients with heart failure and reduced ejection fraction, two trials (EMPEROR-Reduced and DAPA-HF) also found a significantly lower risk of reaching the secondary renal endpoint in those treated with an SGLT2 inhibitor in comparison with placebo. This also applied to patients with CKD. Apart from their direct mechanism of action, SGLT2 inhibitors have additional effects that could be of particular interest for patients with non-diabetic CKD. Among these, SGLT2 inhibitors reduce blood pressure and serum acid uric levels and can increase hemoglobin levels. Some safety issues should be further explored in the CKD population. SGLT2 inhibitors can minimally increase potassium levels, but this has not been shown by the CREDENCE trial. They also increase magnesium and phosphate reabsorption. These effects could become more significant in patients with advanced CKD and will need monitoring when these agents are used more extensively in the CKD population. Conversely, they do not seem to increase the risk of acute kidney injury.

Management of bone fragility in type 2 diabetes: Perspective from an interdisciplinary expert panel

AIM

Bone fragility is increasingly recognized as a relevant complication of type 2 diabetes (T2D) and diabetic patients with fragility fractures have higher mortality rates than non diabetic individuals or diabetic patients without fractures. However, current diagnostic approaches for fracture risk stratification, such as bone mineral density measurement or the use of risk assessment algorithms, largely underestimate fracture risk in T2D patients. A multidisciplinary expert panel was established in order to in order to formulate clinical consensus recommendations on bone health assessment and management of fracture risk in patients with T2D.

DATA SYNTHESIS

The following key questions were addressed: a) which are the risk factors for bone fragility in T2D?, b) which diagnostic procedures can be currently used to stratify fracture risk in T2D patients?, c) which are the effects of antidiabetic treatments on bone?, and d) how to prevent and treat bone fragility in T2D patients? Based on the available data members of this panel suggest that the stratification of fracture risk in patients with diabetes should firstly rely on the presence of a previous fragility fracture and on the individual risk profile, with the inclusion of T2D-specific risk factors (namely T2D duration above 10 yrs, presence of chronic T2D complications, use of insulin or thiazolidinediones and persistent HbA1c levels above 8% for at least 1 year). Two independent diagnostic approaches were then suggested in the presence or the absence of a prevalent fragility fracture, respectively.

CONCLUSIONS

Clinical trials in T2D patients at risk for fragility fractures are needed to determine the efficacy and safety of available antiresorptive and anabolic agents in this specific setting.

Metformin: Is It the Well Wisher of Bone Beyond Glycemic Control in Diabetes Mellitus?

Both diabetes mellitus and osteoporosis constitute a notable burden in terms of quality of life and healthcare costs. Diabetes mellitus affecting the skeletal system has been gaining attention in recent years and is now getting recognized as yet another complication of the disease, known as diabetic bone disease. As this condition with weaker bone strength increases fracture risk and reduces the quality of life, so much attention is being paid to investigate the molecular pathways through which both diabetes and its therapy are affecting bone metabolism. Out of many therapeutic agents currently available for managing diabetes mellitus, metformin is one of the most widely accepted first choices worldwide. The purpose of this review is to describe the effects of biguanide-metformin on bone metabolism in type 2 diabetes mellitus including its plausible mechanisms of action on the skeleton. In vitro studies suggest that metformin directly stimulates osteoblasts differentiation and may inhibit osteoclastogenesis by increasing osteoprotegerin expression, both through activation of the AMPK signaling pathway. Several studies in both preclinical and clinical settings report the favorable effects of metformin on bone microarchitecture, bone mineral density, bone turnover markers, and fracture risk. However, animal studies were not specific in terms of the diabetic models used and clinical studies were associated with several confounders. The review highlights some of these limitations and provide future recommendations for research in this area which is necessary to better understand the role of metformin on skeletal outcomes in diabetes.

Effect of sodium-glucose cotransporter 2 inhibitors on cardiovascular and kidney outcomes-Systematic review and meta-analysis of randomized placebo-controlled trials

Sodium-glucose cotransporter 2 inhibitor (SGLT2i) use is associated with improved cardiovascular and kidney outcomes. However, the magnitude and potential heterogeneity of effect across patients with varying types of cardiometabolic and kidney disease is unclear. To examine the effect of SGLT2i on cardiovascular and kidney outcomes among patients with type 2 diabetes mellitus (T2DM), and independent of T2DM status, among patients with heart failure (HF), and chronic kidney disease.

METHOD

Medline, Embase, Cochrane library and scientific conferences were searched from inception till September 24, 2020 for randomized controlled trials comparing cardiovascular and kidney outcomes between SGLT2i and placebo. Random effects hazard ratios (HR) with 95% confidence intervals (CIs) were calculated.

RESULTS

Eight trials with a combined 59,747 patients were included. In the overall population, SGLT2i reduced the risk of all-cause mortality (HR 0.84; 95% CI [0.78-0.91]), cardiovascular mortality (HR 0.84; 95% CI [0.76-0.93]) hospitalization for HF (HR 0.69; 95% CI [0.64-0.74]), myocardial infarction (HR 0.91; 95% CI [0.84-0.99]), and composite kidney outcome (HR 0.62; 95% CI [0.56-0.70]). There was no significant effect on the risk of stroke (HR 0.98; 95% CI [0.86-1.11]). Results were consistent across subgroups stratified by diabetes and HF status. SGLT2i use was not associated with a greater risk of hypoglycemia (OR 0.92; 95% CI [0.84-1.01]) or amputation (OR 1.25; 95% CI [0.97-1.62]). There were 64 diabetic ketoacidosis events with SGLT2i use and 18 with placebo (OR 2.86; 95% CI [1.39-5.86]).

CONCLUSIONS

In patients with cardiometabolic and kidney disease, SGLT2i improved cardiovascular and kidney outcomes, regardless of T2DM, HF, and/or CKD status. The magnitude of risk reduction was largest for hospitalization for HF and progression of kidney disease, more modest for mortality and MI and absent for stroke.

Adverse events associated with sodium glucose co-transporter 2 inhibitors: an overview of quantitative systematic reviews

Background:

Multiple published quantitative systematic reviews have reported on adverse events associated with the use of sodium glucose co-transporter 2 (SGLT-2) inhibitors in patients with type 2 diabetes mellitus.

Aims:

To summarize and appraise the quality of evidence from quantitative systematic reviews assessing adverse events of SGLT-2 inhibitors.

Methods:

We searched PubMed, EMBASE and the Cochrane Library for quantitative systematic reviews assessing SGLT-2 inhibitor safety. Two reviewers extracted data and assessed methodological quality using the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) tool. Main outcomes included pooled and single study point estimaates (in the absence of pooled estimates) with corresponding 95% confidence intervals (CIs) of SGLT-2 inhibitors versus placebo or active comparators for genitourinary infections, volume depletion, acute kidney injury, bone fractures, diabetic ketoacidosis, lower limb amputations, cancers, and other notable adverse events.

Results:

Out of 1289 citations screened, 47 reviews assessed SGLT-2 inhibitor safety, of which 35 were of low quality. Canagliflozin, dapagliflozin and empagliflozin were consistently associated with an increased risk of genital tract infections versus placebo (point estimates ranged from 2.5 to 9.8) and other antihyperglycemic agents (point estimates ranged from 2.7 to 12.0). Canagliflozin and dapagliflozin were associated with an increased risk of diabetic ketoacidosis. Canagliflozin was the only agent associated with an increased amputation risk; however, this was driven by results from a single trial program. Dapagliflozin was the only agent that exhibited a statistically significant increased risk of urinary tract infections. Empagliflozin was associated with a statistically significant increased risk of bladder cancer; however, this finding was susceptible to detection bias. None of the agents were associated with a statistically significant increased risk of acute kidney injury, or bone fractures compared to placebo or mixed (active or placebo) comparators. Upper 95% CI limits do not rule out clinically meaningful outcomes.

Conclusion:

The majority of quantitative systematic reviews reporting on adverse events of SGLT-2 inhibitors were of low methodological quality. Despite almost 50 quantitative systematic reviews published on the safety of SGLT-2 inhibitors, clinicians are still left uncertain of the risks of important adverse effects.

Plain Language Summary

SGLT-2 iInhibitor side effects: overview of reviews

Many published systematic reviews have reported on side effects associated with the use of sodium glucose co-transporter 2 (SGLT-2) inhibitors in patients with type 2 diabetes. We aimed to summarize and appraise the quality of evidence from quantitative systematic reviews assessing side effects of SGLT-2 inhibitors. Using the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) tool, two authors extracted data and assessed the methods of included reviews. Main outcomes included reported pooled and single study point estimates for several SGLT-2 inhibitor side effects such as genital infections, bone fractures, lower limb amputations, increased blood acidity, among others. Of the reviews included in our study, 35 of the 47 reviews assessed were of low quality. Canagliflozin and dapagliflozin were associated with an increased risk of blood acidity in a 2020 review. Canagliflozin was the only agent associated with an increased amputation risk; however, this was driven by results from a single trial program. Dapagliflozin was the only agent that exhibited a significantly increased risk of urinary tract infections. Empagliflozin was associated with an increased risk of bladder cancer; however, this finding was susceptible to bias. None of the agents were associated with an increased risk of kidney injury or bone fractures.

Association between combined treatment with SGLT2 inhibitors and metformin for type 2 diabetes mellitus on fracture risk: a meta-analysis of randomized controlled trials

This study analyzed the effects of combination therapy with sodium-glucose transporter-2 inhibitors (SGLT2is) and metformin on fracture risk. Summarizing available randomized controlled trials, we found that SGLT2is combined with metformin therapy did not influence fracture risk compared with metformin monotherapy or other comparators in patients with T2DM.

INTRODUCTION

No study is available evaluating the association between sodium-glucose transporter-2 inhibitors (SGLT2is) in combination with metformin use and fracture risk. Our study aimed to investigate the fracture risk of combination therapy with SGLT2is and metformin in patients with type 2 diabetes mellitus (T2DM).

METHODS

PubMed, Embase, ClinicalTrials.gov site, and the Cochrane Library databases were scrutinized for all eligible randomized controlled trials (RCTs). The summarized odds ratios (ORs) and their 95% confidence intervals (CI) were calculated using Review Manager 5.3 software.

RESULTS

A total of 25 RCTs involving 19,500 participants with T2DM were included in our studies. There were 88 fracture cases in the SGLT2is in combination with metformin therapy group and 79 in the control group. SGLT2is combined with metformin use did not influence fracture risk compared with metformin monotherapy or other comparators in patients with T2DM (OR = 0.97, 95% CI 0.71-1.32). After stratification by drug type, follow-up time, control regimen, and type of fracture, the upshots were still stable.

CONCLUSION

SGLT2is and metformin combination therapy did not influence fracture risk compared with metformin monotherapy or other comparators in patients with T2DM.

PROSPERO REGISTRATION NUMBER

CRD42020168435.

Update on: effects of anti-diabetic drugs on bone metabolism

INTRODUCTION

Preclinical, clinical, and population-based studies have provided evidence that anti-diabetic drugs affect bone metabolism and may affect the risk of fracture in diabetic patients.

AREAS COVERED

An overview of the skeletal effects of anti-diabetic drugs used in type 2 diabetes is provided. Searches on AdisInsight, PubMed, and Medline databases were conducted up to 1^st July 2020. The latest evidence from randomized clinical trials and population-based studies on the skeletal safety of the most recent drugs (DPP-4i, GLP-1RA, and SGLT-2i) is provided.

EXPERT OPINION

Diabetic patients present with a higher risk of fracture for a given bone mineral density suggesting a role of bone quality in the etiology of diabetic fracture. Bone quality is difficult to assess in human clinical practice and the use of preclinical models provides valuable information on diabetic bone alterations. As several links have been established between bone and energy homeostasis, it is interesting to study the safety of anti-diabetic drugs on the skeleton. So far, evidence for the newest molecules suggests a neutral fracture risk, but further studies, especially in different types of patient populations (patients at risk or with history of cardiovascular disease, renal impairment, neuropathy) are required to fully appreciate this matter.

Potential Safety Issues with Use of Sodium-Glucose Cotransporter 2 Inhibitors, Particularly in People with Type 2 Diabetes and Chronic Kidney Disease

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a major advance in the fields of diabetology, nephrology, and cardiology. The cardiovascular and renal benefits of SGLT2 inhibitors are likely largely independent of their glycaemic effects, and this understanding is central to the use of these agents in the high-risk population of people with type 2 diabetes and chronic kidney disease. There are a number of potential safety issues associated with the use of SGLT2 inhibitors. These include the rare but serious risks of diabetic ketoacidosis and necrotising fasciitis of the perineum. The data regarding a possibly increased risk of lower limb amputation and fracture with SGLT2 inhibitor therapy are conflicting. This article aims to explore the potential safety issues associated with the use of SGLT2 inhibitors, with a particular focus on the safety of these drugs in people with type 2 diabetes and chronic kidney disease. We discuss strategies that clinicians can implement to minimise the risk of adverse effects including diabetic ketoacidosis and volume depletion. Risk mitigation strategies with respect to SGLT2 inhibitor-associated diabetic ketoacidosis are of particular importance during the current coronavirus disease 2019 (COVID-19) pandemic.

How should rheumatologists manage glucocorticoid-induced hyperglycemia?

Glucocorticoid-induced hyperglycemia (GIH) is an important complication to be managed by rheumatologists as it can affect morbidity and mortality of patients. Before administration of glucocorticoids, risk for the development of GIH should be assessed in every patient. A meta-analysis identified male gender, older age, family history of diabetes mellitus, current smoking history, past history of hypertension, higher body mass index, higher fasting plasma glucose (PG) and higher hemoglobin A1c (HbA1c) levels as risk factors for GIH. Then, rheumatologists need to carefully monitored PG levels including 2-h after meals because glucocorticoids particularly affect postprandial glucose metabolism. Fasting PG level ≥ 126 mg/dL and/or post-meal PG level ≥ 200 mg/dL are considered as GIH regardless of HbA1c level. Treatment strategy for GIH should center on insulin injection since the effectiveness of oral hypoglycemic agents for GIH has been uncertain. But, rheumatologists may try oral hypoglycemic agents in advance of insulin therapy for mild GIH, whereas diabetologists should be consulted in case of intractable GIH. More strict control of GIH could be possible using intensive insulin protocol. Rheumatologists are encouraged to be interested in the management of GIH for providing patients superior care, working closely with diabetologists.

Diabetes and Bone Fragility: SGLT2 Inhibitor Use in the Context of Renal and Cardiovascular Benefits

PURPOSE OF REVIEW

Type 2 diabetes mellitus (T2DM) has been shown to negatively impact bone quality and increase fracture risk. While the pathophysiology of bone fragility in T2DM is not clear and likely multifactorial, medications used to treat T2DM are increasingly scrutinized for their potential role in aberrant bone metabolism. Sodium-glucose co-transporter 2 (SGLT2) inhibitors are gaining popularity in patients with T2DM. In addition to lowering blood glucose, there is evidence that these drugs offer cardiac and renal benefit to individuals with T2DM, leading to FDA-approved indications for use in at-risk individuals. At the same time, there remain concerns that SGLT2 inhibitors, specifically canagliflozin, have adverse effects on bone metabolism and increase fracture risk in T2DM. This review seeks to further clarify the impact of these agents on the skeleton.

RECENT FINDINGS

SGLT2 inhibitors may indirectly disrupt calcium and phosphate homeostasis, contribute to weight loss, and cause hypotension, resulting in bone mineral density (BMD) losses and increased falls. The true long-term impact of SGLT2 inhibitors on the diabetic skeleton is still unclear; this review summarizes the results in studies investigating the impact of SGLT2 inhibitors on fracture risk in T2DM. Whereas studies performed with dapagliflozin and empagliflozin have not shown an increased risk of bone fractures compared with placebo, some studies have shown increased markers of bone turnover and reduced bone mineral density with canagliflozin treatment. While an increased fracture risk was observed with canagliflozin in the CANVAS trial (HR 1.26; 95% CI 1.04, 1.52), an increased risk was not seen in the CANVAS-R (HR 0.86) or CREDENCE (HR 0.98) trials. There is substantial evidence of the cardiac and renal protective benefits of SGLT2 inhibitors. There does not appear to be an increased fracture risk with the use of dapagliflozin or empagliflozin. Given the possible association between canagliflozin and adverse bone outcomes described in CANVAS, canagliflozin use should be pursued in individuals with T2DM only after careful consideration of the individual's skeletal risk.

Sodium-Glucose Co-Transporter 2 Inhibitors and Fracture Risk

Patients with type 2 diabetes mellitus (T2DM) appear to have increased risk for fractures. In this context, the finding that canagliflozin, a sodium-glucose co-transporter-2 (SGLT) inhibitor, increased the risk for fracture compared with placebo in the Canagliflozin Cardiovascular Assessment Study (CANVAS), a large randomized controlled trial (RCT) in patients with established cardiovascular disease or multiple cardiovascular risk factors, created concern. In the present review, we summarize the data regarding the association between SGLT2 inhibitors and fracture risk in patients with T2DM. In contrast to the findings reported in CANVAS, canagliflozin did not affect the risk of fracture in a more recent, large RCT in patients with diabetic nephropathy. In addition, empagliflozin and dapagliflozin, other members of this class, also do not appear to affect the incidence of fracture. Moreover, there is no clear pathogenetic mechanism through which SGLT2 inhibitors increase the risk for fractures. Therefore, available data are inconclusive to attribute to these drugs a direct responsibility for bone fractures.

The Effect of Type 2 Diabetes on Bone Biomechanics

PURPOSE OF REVIEW

There is ample evidence that patients with type 2 diabetes (T2D) have increased risk of fracture even though they have normal or high bone mineral density. As a result, poor bone quality is suggested to contribute to skeletal fragility in this population. Thus, our goal was to conduct a comprehensive literature review to understand how bone quality components are altered in T2D and their effects on bone biomechanics and fracture risk.

RECENT FINDINGS

T2D does affect bone quality via alterations in bone microarchitecture, organic matrix, and cellular behavior. Further, studies indicate that bone biomechanical properties are generally deteriorated in T2D, but there are few reports in patients. Additional work is needed to better understand molecular and cellular mechanisms that contribute to skeletal fragility in T2D. This knowledge can contribute to the development of improved diagnostic tools and drug targets to for improved quality of life for those with T2D.

Bone health in diabetes and prediabetes

Bone fragility has been recognized as a complication of diabetes, both type 1 diabetes (T1D) and type 2 diabetes (T2D), whereas the relationship between prediabetes and fracture risk is less clear. Fractures can deeply impact a diabetic patient's quality of life. However, the mechanisms underlying bone fragility in diabetes are complex and have not been fully elucidated. Patients with T1D generally exhibit low bone mineral density (BMD), although the relatively small reduction in BMD does not entirely explain the increase in fracture risk. On the contrary, patients with T2D or prediabetes have normal or even higher BMD as compared with healthy subjects. These observations suggest that factors other than bone mass may influence fracture risk. Some of these factors have been identified, including disease duration, poor glycemic control, presence of diabetes complications, and certain antidiabetic drugs. Nevertheless, currently available tools for the prediction of risk inadequately capture diabetic patients at increased risk of fracture. Aim of this review is to provide a comprehensive overview of bone health and the mechanisms responsible for increased susceptibility to fracture across the spectrum of glycemic status, spanning from insulin resistance to overt forms of diabetes. The management of bone fragility in diabetic patient is also discussed.