Clinical Trials of Heart Failure: Is There a Question of Sex?

Sex and gender-based analysis and diversity metric reporting in acute care trials published in high-impact journals: a systematic review

OBJECTIVE

To characterise sex and gender-based analysis (SGBA) and diversity metric reporting, representation of female/women participants in acute care trials and temporal changes in reporting before and after publication of the 2016 Sex and Gender Equity in Research guideline.

DESIGN

Systematic review.

DATA SOURCES

We searched MEDLINE for trials published in five leading medical journals in 2014, 2018 and 2020.

STUDY SELECTION

Trials that enrolled acutely ill adults, compared two or more interventions and reported at least one clinical outcome.

DATA ABSTRACTION AND SYNTHESIS

4 reviewers screened citations and 22 reviewers abstracted data, in duplicate. We compared reporting differences between intensive care unit (ICU) and cardiology trials.

RESULTS

We included 88 trials (75 (85.2%) ICU and 13 (14.8%) cardiology) (n=111 428; 38 140 (34.2%) females/women). Of 23 (26.1%) trials that reported an SGBA, most used a forest plot (22 (95.7%)), were prespecified (21 (91.3%)) and reported a sex-by-intervention interaction with a significance test (19 (82.6%)). Discordant sex and gender terminology were found between headings and subheadings within baseline characteristics tables (17/32 (53.1%)) and between baseline characteristics tables and SGBA (4/23 (17.4%)). Only 25 acute care trials (28.4%) reported race or ethnicity. Participants were predominantly white (78.8%) and male/men (65.8%). No trial reported gendered-social factors. SGBA reporting and female/women representation did not improve temporally. Compared with ICU trials, cardiology trials reported significantly more SGBA (15/75 (20%) vs 8/13 (61.5%) p=0.005).

CONCLUSIONS

Acute care trials in leading medical journals infrequently included SGBA, female/women and non-white trial participants, reported race or ethnicity and never reported gender-related factors. Substantial opportunity exists to improve SGBA and diversity metric reporting and recruitment of female/women participants in acute care trials.

PROSPERO REGISTRATION NUMBER

CRD42022282565.

Sex as a biological variable for cardiovascular physiology

There have been ongoing efforts by federal agencies and scientific communities since the early 1990s to incorporate sex and/or gender in all aspects of cardiovascular research. Scientific journals provide a critical function as change agents to influence transformation by encouraging submissions for topic areas, and by setting standards and expectations for articles submitted to the journal. As part of ongoing efforts to advance sex and gender in cardiovascular physiology research, the American Journal of Physiology-Heart and Circulatory Physiology recently launched a call for papers on Considering Sex as a Biological Variable. This call was an overwhelming success, resulting in 78 articles published in this collection. This review summarizes the major themes of the collection, including Sex as a Biological Variable Within: Endothelial Cell and Vascular Physiology, Cardiovascular Immunity and Inflammation, Metabolism and Mitochondrial Energy, Extracellular Matrix Turnover and Fibrosis, Neurohormonal Signaling, and Cardiovascular Clinical and Epidemiology Assessments. Several articles also focused on establishing rigor and reproducibility of key physiological measurements involved in cardiovascular health and disease, as well as recommendations and considerations for study design. Combined, these articles summarize our current understanding of sex and gender influences on cardiovascular physiology and pathophysiology and provide insight into future directions needed to further expand our knowledge.

Guidelines on the use of sex and gender in cardiovascular research

In cardiovascular research, sex and gender have not typically been considered in research design and reporting until recently. This has resulted in clinical research findings from which not only all women, but also gender-diverse individuals have been excluded. The resulting dearth of data has led to a lack of sex- and gender-specific clinical guidelines and raises serious questions about evidence-based care. Basic research has also excluded considerations of sex. Including sex and/or gender as research variables not only has the potential to improve the health of society overall now, but it also provides a foundation of knowledge on which to build future advances. The goal of this guidelines article is to provide advice on best practices to include sex and gender considerations in study design, as well as data collection, analysis, and interpretation to optimally establish rigor and reproducibility needed to inform clinical decision-making and improve outcomes. In cardiovascular physiology, incorporating sex and gender is a necessary component when optimally designing and executing research plans. The guidelines serve as the first guidance on how to include sex and gender in cardiovascular research. We provide here a beginning path toward achieving this goal and improve the ability of the research community to interpret results through a sex and gender lens to enable comparison across studies and laboratories, resulting in better health for all.

Sex Differences in the Effectiveness of Angiotensin-Converting Enzyme Inhibitors, Angiotensin II Receptor Blockers, and Sacubitril-Valsartan for the Treatment of Heart Failure

Background PARAGON-HF (Efficacy and Safety of LCZ696 Compared to Valsartan, on Morbidity and Mortality in Heart Failure Patients With Preserved Ejection Fraction) suggested a potential benefit of sacubitril-valsartan in women with preserved ejection fraction. Among patients with heart failure previously treated with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs), we studied whether effectiveness of treatment with sacubitril-valsartan compared with ACEI/ARB monotherapy differed between men and women for both preserved and reduced ejection fraction. Methods and Results Data were derived from the Truven Health MarketScan Databases between January 1, 2011, and December 31, 2018. We included patients with a primary diagnosis of heart failure on treatment with ACEIs, ARBs, or sacubitril-valsartan on the basis of the first prescription after diagnosis. A total of 7181 patients treated with sacubitril-valsartan, 25 408 patients using an ACEI, and 16 177 patients treated with ARBs were included. A total of 790 readmissions or deaths occurred among 7181 patients in the sacubitril-valsartan group and 11 901 events in 41 585 patients treated with an ACEI/ARB. Adjusted for covariates, the hazard ratio (HR) for treatment with sacubitril-valsartan compared with an ACEI or ARB was 0.74 (95% CI, 0.68-0.80). The protective effect of sacubitril-valsartan was evident for men and women (women: HR, 0.75 [95% CI, 0.66-0.86]; P<0.01; men: HR, 0.71 [95% CI, 0.64-0.79]; P<0.01; P interaction 0.03). A protective effect for both sexes was seen only among those with systolic dysfunction. Conclusions Treatment with sacubitril-valsartan is more effective at reducing death and admission to the hospital for heart failure compared with ACEIs/ARBs similarly among men and women with systolic dysfunction; sex differences in the effectiveness of sacubitril-valsartan in diastolic dysfunction requires further investigation.