Are novel glucose-lowering agents' cardiorenal benefits generalizable to individuals of Black race? A meta-trial sequential analysis to address disparities in cardiovascular and renal outcome trials enrolment

Socioeconomic aspects of incretin-based therapy

Incretin-based therapies, particularly glucagon-like peptide-1 receptor agonists (GLP-1 RAs), have demonstrated cardiovascular benefits in people with type 2 diabetes. However, socioeconomic disparities in their uptake may constrain the collective advantages offered by these medications to the broader population. In this review we examine the socioeconomic disparities in the utilisation of incretin-based therapies and discuss strategies to address these inequalities. Based on real-world evidence, the uptake of GLP-1 RAs is reduced in people who live in socioeconomically disadvantaged areas, have low income and education level, or belong to racial/ethnic minorities, even though these individuals have a greater burden of type 2 diabetes and cardiovascular disease. Contributing factors include suboptimal health insurance coverage, limited accessibility to incretin-based therapies, financial constraints, low health literacy and physician-patient barriers such as provider bias. Advocating for a reduction in the price of GLP-1 RAs is a pivotal initial step to enhance their affordability among lower socioeconomic groups and improve their value-for-money from a societal perspective. By implementing cost-effective strategies, healthcare systems can amplify the societal benefits of incretin-based therapies, alongside measures that include maximising treatment benefits in specific subpopulations while minimising harms in vulnerable individuals, increasing accessibility, enhancing health literacy and overcoming physician-patient barriers. A collaborative approach between governments, pharmaceutical companies, healthcare providers and people with diabetes is necessary for the effective implementation of these strategies to enhance the overall societal benefits of incretin-based therapies.

Ethnic Variations in Cardiovascular and Renal Outcomes From Newer Glucose-Lowering Drugs: A Meta-Analysis of Randomized Outcome Trials

Background Hispanic populations are more likely to develop diabetes and its related diseases than non-Hispanic White populations. Little evidence exists to support whether the cardiovascular and renal benefits of sodium-glucose cotransporter 2 inhibitors and glucagon-like peptide-1 receptor agonists are generalizable to the Hispanic populations. Methods and Results We included the cardiovascular and renal outcome trials (up to March 2021) that reported the major adverse cardiovascular events (MACEs), cardiovascular death/hospitalization for heart failure, and composite renal outcomes by ethnicity in individuals with type 2 diabetes (T2D), calculated pooled hazard ratios (HRs) with 95% CIs using fixed-effects models, and tested the differences between Hispanic and non-Hispanic populations (P for interaction [P_interaction]). In 3 sodium-glucose cotransporter 2 inhibitor trials, there was a statistically significant difference between Hispanic (HR, 0.70 [95% CI, 0.54-0.91]) and non-Hispanic (HR, 0.96 [95% CI, 0.86-1.07]) groups in treatment effects on MACE risk (P_interaction=0.03), except for risks of cardiovascular death/hospitalization for heart failure (P_interaction=0.46) and composite renal outcome (P_interaction=0.31). In 5 glucagon-like peptide-1 receptor agonist trials, there was no statistically significant difference in treatment effect on MACE risk between Hispanic (HR, 0.82 [95% CI, 0.70-0.96]) and non-Hispanic (HR, 0.92 [95% CI, 0.84-1.00]) populations (P_interaction=0.22). In 3 dipeptidyl peptidase-4 inhibitor trials, the HR for MACE risk appeared greater in Hispanic (HR, 1.15 [95% CI, 0.98-1.35]) than non-Hispanic (HR, 0.96 [95% CI, 0.88-1.04]) populations (P_interaction=0.045). Conclusions Compared with non-Hispanic individuals, Hispanic individuals with T2D appeared to obtain a greater benefit of lowered MACE risk with sodium-glucose cotransporter 2 inhibitors.

Exploring ethnic representativeness in diabetes clinical trial enrolment from 2000 to 2020: a chronological survey

AIMS/HYPOTHESIS

Ethnic representativeness of participant enrolment in diabetes RCTs involving multiple ethnicities remains unknown. The aims of this study were to evaluate the status and temporal trend of ethnic representativeness in enrolment to diabetes RCTs, and to assess under-enrolment of non-white ethnic groups and explore trial characteristics associated with under-enrolment.

METHODS

We conducted a chronological survey by systematically searching the literature to include eligible RCTs published between January 2000 and December 2020. We assessed temporal trends in enrolment of ethnic groups in the included trials. Univariable logistic regression was used to explore the association between trial characteristics and under-enrolment of non-white groups, using a participant to prevalence ratio of <0.8 to define under-enrolment. This study was registered in PROSPERO (CRD42021229100).

RESULTS

We included 405 RCTs for analysis (327 multi-country trials, 69 conducted in the USA and nine conducted in the UK). The median enrolment rate of all non-white groups was 24.0% in the overall RCTs. Trials conducted in the USA and the UK had median enrolment rates of 29.0% and 12.0% for all non-white groups, respectively. There was a temporal trend towards increased participation of non-white ethnic groups in the overall RCTs; however, no significant improvement over time was found in the US or UK trials. Non-white groups were under-enrolled in most included trials: 62.3% (43/69) in US trials and 77.8% (7/9) in UK trials. The US trials with a high female proportion were associated with lower odds of under-enrolment of all non-white groups (OR 0.22; 95% CI 0.07, 0.65), while trials receiving funding from industry showed increased odds of under-enrolment (OR 4.64; 95% CI 1.50, 14.35). Outpatient enrolment and intervention duration were significantly associated with under-enrolment of Black participants. Only a small proportion of trials reported subgroup results or explored the effect modification by ethnicity.

CONCLUSIONS/INTERPRETATION

A temporal trend towards increased non-white ethnic enrolment was found in diabetes RCTs globally, but not in the USA or the UK. Non-white ethnic groups were under-represented in the majority of diabetes trials conducted in the USA and the UK. Some trial characteristics may be associated with non-white under-enrolment in diabetes trials. These findings provide some evidence for non-white ethnic representativeness in diabetes trials over the past two decades, and highlight the need for more effective strategies and endeavours to alleviate under-enrolment of non-white ethnic groups.