Kidney and Cardiovascular Effects of Canagliflozin According to Age and Sex: A Post Hoc Analysis of the CREDENCE Randomized Clinical Trial

The Efficacy and Safety of Canagliflozin by Frailty Status in Participants of the CANVAS and CREDENCE Trials

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have been shown to improve renal and cardiovascular outcomes in patients with type 2 diabetes. Limited evidence exists about the efficacy and safety of SGLT2 inhibitors in patients with frailty.

METHODS

This was a post hoc pooled, participant-level data analysis of the CANVAS Program (CANVAS and CANVAS-R) and the CREDENCE trial. We examined the effect of canagliflozin on: (1) Major adverse cardiovascular events (MACE), (2) Cardiovascular mortality, (3) all-cause mortality, and (4) key safety outcomes. Frailty was defined by a Frailty Index (FI) based on a deficit accumulation approach (FI > 0.25: frail). Cox proportional-hazard models were used to estimate the efficacy and safety of canagliflozin overall and according to frailty status.

RESULTS

There were 14,543 participants (10,142 from the CANVAS Program, 4401 from the CREDENCE trial). Their mean age was 63.2 years; 35.3% were female. Frailty was present in 56% of the study participants. The benefits of canagliflozin were observed in both the frail and non-frail subgroups: HRs for MACE 0.80 (95% CI 0.70-0.90) in the frail versus 0.91 (95% CI 0.75-1.09) in the non-frail (p for interaction = 0.27); HRs for cardiovascular mortality 0.79 (95% CI 0.67-0.95) in the frail versus 0.94 (95% CI 0.70-1.27) in the non-frail (p for interaction = 0.38); HRs for all-cause mortality 0.81 (95% CI 0.70-0.94) in the frail versus 0.93 (95% CI 0.74-1.16) in the non-frail (p for interaction = 0.39). Adverse events were similar among frail and non-frail participants, except for osmotic diuresis (HRs 1.67, 95% CI 1.22-2.28 in the frail vs. 3.05, 95% CI 2.13-4.35 in the non-frail, p for interaction = 0.01).

CONCLUSIONS

Canagliflozin improved cardiovascular and mortality endpoints in participants with type 2 diabetes irrespective of frailty status, with a similar safety profile. Our findings, in addition to those from other recent studies, provide evidence to support the introduction of SGLT2 inhibitor therapy in patients perceived to be frail.

TRIAL REGISTRATION

ClinicalTrials.gov CANVAS: NCT01032629; CANVAS-R: NCT01989754; CREDENCE: NCT02065791.

Safety and Efficacy of Sodium-Glucose Cotransporter 2 Inhibitors in Older Adults with Variable Disease States: A Meta-analysis of Large Placebo-Controlled Trials

BACKGROUND

Recent guidelines recommend the use of sodium-glucose cotransporter 2 (SGLT-2) inhibitors (SGLT2i) in patients suffering from cardiorenal diseases. However, the safety and efficacy of SGLT2i in older adults with atherosclerotic cardiovascular disease (ASCVD), heart failure (HF), and chronic kidney disease (CKD) remain unclear.

METHODS

Online databases were queried from inception to 11 July 2023 to identify primary or secondary analyses for inclusion. Efficacy outcomes included all-cause mortality, cardiovascular (CV) death, hospitalization for heart failure (HHF), major adverse cardiac events (MACE), CV death/HHF composite, and cardiorenal composite events. Safety endpoints included acute kidney injury (AKI), serious adverse events, genital infections, limb amputation, fractures, urinary tract infections (UTI), and volume depletion. Data were pooled using a random-effects model to derive risk ratios (RRs) and 95% confidence intervals (CIs).

RESULTS

Eight trials with 32,541 older adults identified in primary or secondary analyses were included. In older adults, SGLT2i reduced the risk of all-cause mortality (RR 0.88; 95% CI 0.83- 0.95), CV death (RR 0.82; 95% CI 0.74-0.92), HHF (RR 0.72; 95% CI 0.66-0.79), MACE (RR 0.87; 95% CI 0.77-0.99), CV death/HHF composite (RR 0.78; 95% CI 0.70-0.88), and cardiorenal composite events (RR 0.77; 95% CI 0.70-0.85). For safety endpoints, SGLT2i decreased the risk of serious adverse events (RR 0.92; 95% CI 0.89-0.95) and increased the risk of genital infections (RR 3.48; 95% CI 2.58-4.69).

CONCLUSIONS

This analysis of randomized trials demonstrates that SGLT2i are efficacious in older adults. However, since older individuals are often underrepresented in most clinical trials, further research targeting this growing demographic is essential.

One or two? Comparison of the cardiorenal effects between combination therapy and monotherapy with SGLT2i or GLP1RA

OBJECTIVE

This study aimed to evaluate the cardiorenal effect of combining sodium-glucose cotransporter 2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) when compared with monotherapy of either agent in patients with type 2 diabetes (T2D).

METHODS

PubMed, Web of Science, Embase, the Cochrane Central Register of Controlled Trials and Clinicaltrial.gov were systematically searched from inception to June 2024. Eligible studies included randomised controlled trials and observational studies assessing that compared with SGLT2i or GLP-1RA monotherapy, the risk of cardiorenal outcomes in patients with T2D who treated with combination therapy. Pooled relative risk (RR) and 95% confidence intervals (CIs) were computed in random-effects model.

RESULTS

In all, five RCTs, 10 post hoc analyses and one observational study were included. The reduced risk of the composite cardiovascular outcome was observed in patients receiving combination therapy of SGLT2i and GLP-1RA when compared with SGLT2i monotherapy (RR = 0.57, 95% CI 0.38-0.86, p = 0.008) or GLP-1RA monotherapy (RR = 0.77, 95% CI 0.65-0.91, p = 0.002). Likewise, the composite renal adverse events were less frequent in patients receiving combination therapy of SGLT2i and GLP-1RA when compared with SGLT2i monotherapy (RR = 0.69, 95% CI 0.59-0.82, p < 0.001) or GLP-1RA monotherapy (RR = 0.66, 95% CI 0.53-0.83, p < 0.001). Compared with GLP-1RA monotherapy, the combination therapy of SGLT2i and GLP-1RA was associated with lower risks of heart failure-related outcomes (RR = 0.63, 95% CI 0.51-0.77, p < 0.001) and all-cause mortality (RR = 0.66, 95% CI 0.50-0.88, p = 0.004) in patients with T2D.

CONCLUSION

The cardiorenal benefits might be magnified with the combination therapy of SGLT2i and GLP-1RA when compared with monotherapy of either agent. Further investigations are needed to validate the findings.

The use of SGLT2 inhibitors and GLP-1 receptor agonists in older patients: a debate on approaches in CKD and non-CKD populations

The management of CKD in older patients presents a significant challenge in modern medicine. As the global population ages, the prevalence of CKD among older adults is increasing, which demands effective and safe treatment strategies. The introduction of sodium-glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists has revolutionized the treatment of CKD, offering potential benefits beyond traditional therapies. However, their use in the older population raises essential questions about safety and efficacy, given the unique physiological changes and comorbidities associated with aging. In this CKJ controversy paper, Roberto Minutolo (PRO) and Sophie Liabeuf (CON) debate on the use of SGLT2 inhibitors and GLP-1 receptor agonists in older patients with CKD. Roberto Minutolo advocates the benefits of these medications, highlighting their role in improving cardiovascular outcomes and slowing CKD progression in older patients. He emphasizes the importance of personalized treatment plans based on the patient's cardio-renal risk profile and preferences. In contrast, Sophie Liabeuf expresses concerns about the safety of these drugs in older adults, citing risks such as fractures, acute kidney injury, and urinary tract infections. She argues that treatment decisions should be guided by patient frailty rather than chronological age, as frail individuals are more vulnerable to adverse drug effects. Both contenders agree on the need for more inclusive clinical trials to better understand the impact of these treatments on older populations. While Roberto Minutolo and Sophie Liabeuf present differing perspectives on the use of SGLT2 inhibitors and GLP-1 receptor agonists in older patients with CKD, their views can be seen as complementary rather than strictly opposing. Minutolo's focus on the benefits of these drugs underscores their potential to improve outcomes. Liabeuf's emphasis on caution and the consideration of frailty highlights the need for careful patient assessment. Both agree on the importance of personalized treatment and the inclusion of older patients in future clinical trials, suggesting a shared goal of optimizing care for this vulnerable population. Their debate underscores the complexity of treatment decisions and the necessity of balancing risks and benefits in managing CKD in older adults.

Cost-effectiveness of sodium-glucose cotransporter-2 inhibitors in the treatment of diabetic nephropathy in Japan

AIM

To assess the cost-effectiveness of diabetic nephropathy treatment with sodium-glucose cotransporter-2 (SGLT2) inhibitors in Japanese clinical practice, considering diabetes-related complications.

MATERIALS AND METHODS

A population-based Monte Carlo simulation was used to estimate the cost-effectiveness for people with diabetic nephropathy who initiated pharmacotherapy with an SGLT2 inhibitor plus conventional treatment or conventional treatment alone, based on quality-adjusted life-years (QALYs) and healthcare costs. The Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation study (CREDENCE) and the Japanese Society for Dialysis Research statistical survey were the primary sources of probability and mortality, while Japanese Health Insurance Claims Data were the cost source. The state transition model included diabetic nephropathy, hospitalization due to cardiovascular disease, dialysis, and death. One-way and probabilistic sensitivity analyses were used to explore model uncertainty.

RESULTS

Using the threshold of JPY 5 000 000 per QALY, SGLT2 inhibitor plus conventional treatment was more cost-effective than conventional treatment alone, with an incremental cost-effectiveness ratio of JPY 654 309 per QALY. Treating 100 000 people, SGLT2 inhibitor plus conventional treatment prevented 2234 deaths and reduced 5793 fewer heart failure cases, 3967 fewer myocardial infarctions and stroke events. Sensitivity analysis affirmed the robustness of these results for patients aged under 70 years.

CONCLUSIONS

The SGLT2 inhibitor treatment appeared to be cost-effective for the overall population of our study and particularly for younger patients (<70 years old). For older patients (≥70 years old), the cost-effectiveness was less clear and may require further evaluation. Decision-makers should consider this age-based heterogeneity when making recommendations about SGLT2 inhibitor treatment.

Chronic kidney disease in older adults: challenges and opportunities for the primary care provider

Kidney disease and its comorbidities disproportionately affect older persons. Kidney disease modifying therapy is underutilized in older adults, as guidelines lack consensus on approaching diagnosis and treatment in older adults. This review aims to highlight the challenges presented by, and opportunities for, identifying and treating CKD in older adults.

Geographic and racial variability in kidney, cardiovascular and safety outcomes with canagliflozin: A secondary analysis of the CREDENCE randomized trial

AIM

To explore the effect of canagliflozin on kidney and cardiovascular events and safety outcomes in individuals with type 2 diabetes and chronic kidney disease across geographic regions and racial groups.

MATERIALS AND METHODS

A stratified Cox proportional hazards model was used to assess efficacy and safety outcomes by geographic region and racial group. The primary composite outcome was a composite of end-stage kidney disease (ESKD), doubling of the serum creatinine (SCr) level, or death from kidney or cardiovascular causes. Secondary outcomes included: (i) cardiovascular death or heart failure (HF) hospitalization; (ii) cardiovascular death, myocardial infarction (MI) or stroke; (iii) HF hospitalization; (iv) doubling of the SCr level, ESKD or kidney death; (v) cardiovascular death; (vi) all-cause death; and (vii) cardiovascular death, MI, stroke, or hospitalization for HF or for unstable angina.

RESULTS

The 4401 patients were divided into six geographic region subgroups: North America (n = 1182, 27%), Central and South America (n = 941, 21%), Eastern Europe (n = 947, 21%), Western Europe (n = 421, 10%), Asia (n = 749, 17%) and Other (n = 161, 4%). The analyses included four racial groups: White (n = 2931, 67%), Black or African American (n = 224, 5%), Asian (n = 877, 20%) and Other (n = 369, 8%). Canagliflozin reduced the relative risk of the primary composite outcome in the overall trial by 30% (hazard ratio 0.70, 95% confidence interval 0.59-0.82; P = 0.00001). Across geographic regions and racial groups, canagliflozin consistently reduced the primary composite endpoint without evidence of heterogeneity (interaction P values of 0.39 and 0.91, respectively) or significant safety outcome differences.

CONCLUSIONS

Canagliflozin reduces the risk of kidney and cardiovascular events similarly across geographic regions and racial groups.

Evaluation of glucose-lowering medications in older people: a comprehensive systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Type 2 diabetes mellitus (T2DM) is increasingly being diagnosed in older adults. Our objective is to assess the advantages and potential drawbacks of different glucose-lowering medications in this specific population.

METHODS

A network meta-analysis was conducted to identify randomized controlled trials that examined patient-centered outcomes in adults aged ≥65 years with T2DM. We searched PubMed, Cochrane CENTRAL, and Embase up to September 23, 2023. Quality of eligible studies were assessed using the Cochrane RoB 2.0 tool.

RESULTS

A total of 22 trials that involved 41 654 participants were included, incorporating sodium-glucose cotransporter-2 (SGLT2) inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1RAs), dipeptidyl peptidase-4 (DPP-4) inhibitors, metformin, sulfonylureas (SU) and acarbose. Our findings reveal that GLP-1RAs reduce the risk of major adverse cardiovascular events (risk ratio [RR], 0.83; 95% confidence interval [CI], 0.71 to 0.97) and body weight (mean difference [MD], -3.87 kg; 95% CI, -5.54 to -2.21). SGLT2 inhibitors prevent hospitalization for heart failure (RR, 0.66; 95% CI, 0.57 to 0.77), renal composite outcome (RR, 0.69; 95% CI, 0.53 to 0.89), and reduce body weights (MD, -1.85 kg; 95% CI, -2.42 to -1.27). SU treatment increases the risk of any hypoglycaemia (RR, 4.19; 95% CI, 3.52 to 4.99) and severe hypoglycaemia (RR, 7.06; 95% CI, 3.03 to 16.43). GLP-1RAs, SGLT2 inhibitors, metformin, SU and DPP-4 inhibitors are effective in reducing glycaemic parameters. Notably, the number of treatments needed decreases in most cases as age increases.

CONCLUSIONS

Novel glucose-lowering medications with benefits that outweigh risks should be prioritized for older patients with diabetes.

SGLT2 Inhibitor Use in Chronic Kidney Disease: Supporting Cardiovascular, Kidney, and Metabolic Health

Originally developed for use in type 2 diabetes mellitus (T2DM), sodium-glucose co-transporter-2 (SGLT2) inhibitors demonstrated diverse cardiovascular- and kidney-protective effects in large outcome trials. Their subsequent approval as a treatment for chronic kidney disease (CKD) marked a pivotal shift in the landscape of CKD management. Further to this, the approval of dapagliflozin and empagliflozin for use in patients with CKD with and without T2DM afforded new treatment opportunities for this population. SGLT2 inhibitors provide an effective treatment for CKD with a favorable safety profile. However, their uptake has been slow, especially among patients without T2DM, owing perhaps to a lack of certainty and familiarity among health care professionals. As the landscape of CKD management continues to evolve, health care professionals should remain knowledgeable about these changes, and implement new guideline recommendations promptly to avoid therapeutic inertia. SGLT2 inhibitors are recommended for patients with CKD with or without T2DM and are foundational agents to support cardiovascular, kidney, and metabolic health. In this review, we provide evidence-based answers to questions that may be asked in the clinic regarding the use of SGLT2 inhibitors to treat CKD.

Effect of SGLT2 inhibitors on heart failure outcomes and cardiovascular death across the cardiometabolic disease spectrum: a systematic review and meta-analysis

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors have been studied in patients with heart failure, type 2 diabetes, chronic kidney disease, atherosclerotic cardiovascular disease, and acute myocardial infarction. Individual trials were powered to study composite outcomes in one disease state. We aimed to evaluate the treatment effect of SGLT2 inhibitors on specific clinical endpoints across multiple demographic and disease subgroups.

METHODS

In this systematic review and meta-analysis, we queried online databases (PubMed, Cochrane CENTRAL, and SCOPUS) up to Feb 10, 2024, for primary and secondary analyses of large trials (n>1000) of SGLT2 inhibitors in patients with heart failure, type 2 diabetes, chronic kidney disease, and atherosclerotic cardiovascular disease (including acute myocardial infarction). Outcomes studied included composite of first hospitalisation for heart failure or cardiovascular death, first hospitalisation for heart failure, cardiovascular death, total (first and recurrent) hospitalisation for heart failure, and all-cause mortality. Effect sizes were pooled using random-effects models. This study is registered with PROSPERO, CRD42024513836.

FINDINGS

We included 15 trials (N=100 952). Compared with placebo, SGLT2 inhibitors reduced the risk of first hospitalisation for heart failure by 29% in patients with heart failure (hazard ratio [HR] 0·71 [95% CI 0·67-0·77]), 28% in patients with type 2 diabetes (0·72 [0·67-0·77]), 32% in patients with chronic kidney disease (0·68 [0·61-0·77]), and 28% in patients with atherosclerotic cardiovascular disease (0·72 [0·66-0·79]). SGLT2 inhibitors reduced cardiovascular death by 14% in patients with heart failure (HR 0·86 [95% CI 0·79-0·93]), 15% in patients with type 2 diabetes (0·85 [0·79-0·91]), 11% in patients with chronic kidney disease (0·89 [0·82-0·96]), and 13% in patients with atherosclerotic cardiovascular disease (0·87 [0·78-0·97]). The benefit of SGLT2 inhibitors on both first hospitalisation for heart failure and cardiovascular death was consistent across the majority of the 51 subgroups studied. Notable exceptions included acute myocardial infarction (22% reduction in first hospitalisation for heart failure; no effect on cardiovascular death) and heart failure with preserved ejection fraction (26% reduction in first hospitalisation for heart failure; no effect on cardiovascular death).

INTERPRETATION

SGLT2 inhibitors reduced heart failure events and cardiovascular death in patients with heart failure, type 2 diabetes, chronic kidney disease, and atherosclerotic cardiovascular disease. These effects were consistent across a wide range of subgroups within these populations. This supports the eligibility of a large population with cardiorenal-metabolic diseases for treatment with SGLT2 inhibitors.

FUNDING

None.

Fibrosis in Chronic Kidney Disease: Pathophysiology and Therapeutic Targets

Chronic kidney disease (CKD) is a slowly progressive condition characterized by decreased kidney function, tubular injury, oxidative stress, and inflammation. CKD is a leading global health burden that is asymptomatic in early stages but can ultimately cause kidney failure. Its etiology is complex and involves dysregulated signaling pathways that lead to fibrosis. Transforming growth factor (TGF)-β is a central mediator in promoting transdifferentiation of polarized renal tubular epithelial cells into mesenchymal cells, resulting in irreversible kidney injury. While current therapies are limited, the search for more effective diagnostic and treatment modalities is intensive. Although biopsy with histology is the most accurate method of diagnosis and staging, imaging techniques such as diffusion-weighted magnetic resonance imaging and shear wave elastography ultrasound are less invasive ways to stage fibrosis. Current therapies such as renin-angiotensin blockers, mineralocorticoid receptor antagonists, and sodium/glucose cotransporter 2 inhibitors aim to delay progression. Newer antifibrotic agents that suppress the downstream inflammatory mediators involved in the fibrotic process are in clinical trials, and potential therapeutic targets that interfere with TGF-β signaling are being explored. Small interfering RNAs and stem cell-based therapeutics are also being evaluated. Further research and clinical studies are necessary in order to avoid dialysis and kidney transplantation.

Emerging role of antidiabetic drugs in cardiorenal protection

The global prevalence of diabetes mellitus (DM) has led to widespread multi-system damage, especially in cardiovascular and renal functions, heightening morbidity and mortality. Emerging antidiabetic drugs sodium-glucose cotransporter 2 inhibitors (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP-1RAs), and dipeptidyl peptidase-4 inhibitors (DPP-4i) have demonstrated efficacy in preserving cardiac and renal function, both in type 2 diabetic and non-diabetic individuals. To understand the exact impact of these drugs on cardiorenal protection and underlying mechanisms, we conducted a comprehensive review of recent large-scale clinical trials and basic research focusing on SGLT2i, GLP-1RAs, and DPP-4i. Accumulating evidence highlights the diverse mechanisms including glucose-dependent and independent pathways, and revealing their potential cardiorenal protection in diabetic and non-diabetic cardiorenal disease. This review provides critical insights into the cardiorenal protective effects of SGLT2i, GLP-1RAs, and DPP-4i and underscores the importance of these medications in mitigating the progression of cardiovascular and renal complications, and their broader clinical implications beyond glycemic management.

Hippo/YAP signaling pathway: a new therapeutic target for diabetes mellitus and vascular complications

Diabetic angiopathy, which includes diabetic kidney disease (DKD), cardio-cerebrovascular disease, and diabetic retinopathy (DR) among other diseases, is one of the most common complications affecting diabetic patients. Among these, DKD, which is a major cause of morbidity and mortality, affects about 40% of diabetic patients. Similarly, DR involves retinal neovascularization and neurodegeneration as a result of chronic hyperglycemia and is the main cause of visual impairment and blindness. In addition, inflammation also promotes atherosclerosis and diabetes, with atherosclerosis-related cardiovascular diseases being often a main cause of disability or death in diabetic patients. Given that vascular diseases caused by diabetes negatively impact human health, it is therefore important to identify appropriate treatments. In this context, some studies have found that the Hippo/Yes-associated protein (YAP) pathway is a highly evolutionarily conserved protein kinase signal pathway that regulates organ growth and size through its effector signaling pathway Transcriptional co-Activator with PDZ-binding motif (TAZ) and its YAP. YAP is a key factor in the Hippo pathway. The activation of YAP regulates gluconeogenesis, thereby regulating glucose tolerance levels; silencing the YAP gene thereby prevents the formation of glomerular fibrosis. YAP can combine with TEA domain family members to regulate the proliferation and migration of retinal vascular endothelial cells (ECs), so YAP plays a prominent role in the formation and pathology of retinal vessels. In addition, YAP/TAZ activation and translocation to the nucleus promote endothelial inflammation and monocyte-EC attachment, which can increase diabetes-induced cardiovascular atherosclerosis. Hippo/YAP signaling pathway provides a potential therapeutic target for diabetic angiopathy, which can prevent the progression of diabetes to DR and improve renal fibrosis and cardio-vascular atherosclerosis.

Sex-dependent effects of Canagliflozin on kidney protection in mice with combined hypertension-type 1 diabetes

Canagliflozin (CANA) is a sodium-glucose cotransporter 2 (SGLT2) inhibitor with blood glucose lowering effects. CANA also promotes kidney protection in patients with cardiovascular diseases and type 2 diabetes (T2D), as well as in normoglycemic patients with hypertension or heart failure. Clinical studies, although conduct in both sexes, do not report sex-dependent differences in T2DM treated with CANA. However, the impact of CANA in type 1 diabetes, as well in sex-dependent outcomes in such cohort needs further understanding. To analyze the effects of CANA in mice with combined hypertension and type 1 diabetes, diabetes was induced by STZ injection (5 days, 50mg/kg/day) in both male and female 8 weeks old genetic hypertensive mice (Lin), whereas the control (Lin) received 0.1M sodium citrate injections. 8 weeks after STZ. Mice were fed either regular or CANA-infused diet for 4 weeks. 8 weeks after STZ, hyperglycemia was present in both male and female mice. CANA reversed BG increase mice fed regular diet. Male LinSTZ mice had elevated water intake, urine output, urinary albumin to creatinine ratio (ACR), kidney lesion score, and creatinine clearance compared to the Lin control group. Kidney injury was improved in male LinSTZ + CANA group in male mice. Water intake and urine output were not statistically significantly different in female LinSTZ compared to female LinSTZ+ CANA. Moreover, CANA did not improve kidney injury in female mice, showing no effect in creatinine clearance, lesion score and fibrosis when compared to LinSTZ fed regular diet. Here we show that Canagliflozin might exert different kidney protection effects in male compared to female mice with hypertension and type 1 diabetes. Sex-dimorphisms were previously found in the pathophysiology of diabetes induced by STZ. Therefore, we highlight the importance of in-depth investigation on sex-dependent effects of CANA, taking in consideration the unique characteristics of disease progression for each sex.