The importance of sex and gender in medical research.
For many years it was widely assumed that the occurrence and outcome of disease was the same for women and men.
Our understanding was that studies involving only men would be equally relevant for women. In the last two decades however, it has been shown that this assumption is highly prejudice and can have a detrimental impact on the health of women.
It is, therefore, really important to incorporate a sex and gender research lens in to medical research.
First, Kelly makes the important distinction between sex and gender and how this can impact medical diagnosis, treatment and outcomes.
Then, she identifies how the incorporation of sex and gender into research has allowed for advancements across healthcare. Improved accuracy, avoiding misinterpretation, reduced unintentional bias and greater social equity to name a few.
In this presentation, Kelly Thompson refers to case studies to examine the differences in the interpretation of health data when examining through a sex and gender research lens.
The severity of disease, risk factors and treatment effectiveness are just a few of the reasons why this is so important.
Kelly encourages researchers to ensure gender diversity in the research team and to explain how sex and gender are accounted for in research applications moving forward.
From CodaZero Live, tune into this fascinating discussion on the importance of sex and gender in medical research by Kelly Thompson.
2. Responsible science: sex and gender analyses
Kelly Thompson
Research Fellow / Program Manager
Global Women’s Health & Critical Care
3. Overview
3
• Definitions
• Importance of conducting sex and gender disaggregated analysis
• Case studies
• Heart disease
• COVID-19
• Sepsis and septic shock
• Recommendations
• Questions
4. Sex and Gender
4
• Sex biological attributes that distinguish organisms as male, female,
intersex and hermaphrodite
• Gender psychological, social and cultural factors that shape attitudes,
behaviours, stereotypes, technologies and knowledge.
3 dimensions:
• Gender norms - rules in culture that influence individuals
• Gender identity - how individuals and groups perceive and
present themselves within cultures
• Gender relations - power relations between individuals with
different gender roles and identities
Tannenbaum et al, Nature, 2019
5. Importance of sex and gendered analysis
5
• Better science
o Rigorous
o Reproducible
o Responsible
• Enables advancements
• Fosters scientific discovery
• Improves experimental efficiency
• Enables social equity
Tannenbaum et al, Nature, 2019
6. Case study: coronary heart disease
Using routinely collected health data, data from large-scale
studies and meta-analyses
Has identified:
• Presentation differences
Acute Myocardial Infarction
Men significantly less likely than women to complain of:
• Neck pain OR = 0.52; 95% CI: 0.35, 0.78
• Back pain OR = 0.38; 95% CI: 0.26, 0.56
• Jaw pain OR = 0.50; 95% CI: 0.31, 0.81
• Nausea OR = 0.58; 95% CI: 0.45, 0.75
6
Goldberg et al, JAHA, 1998
8. + 44%
Peters et al., Lancet, 2014
Peters et al., Diabetologia, 2014
Diabetes and CVD
9. Peters et al, Diabetalogia 2016
Number of children
Hazard
ratio
(95%
CI)
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0 1 2 3 >3
Women (No. events = 5579)
9
China Kadoorie Biobank:
7-year risk of incident diabetes
10. China Kadoorie Biobank:
7-year risk of incident diabetes
Peters et al, Diabetalogia 2016
Number of children
Hazard
ratio
(95%
CI)
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0 1 2 3 >3
Women (No. events = 5579)
Men (No. events = 3261)
10
13. - Open-label trial of daily dexamethasone (6mg IV or oral), for up to 10 days vs. usual care
- Primary outcome 28 day mortality
- Subgroups by illness severity based on oxygen requirements
- 6425 participants (2104 assigned dex. vs. 4321 assigned usual care)
Conclusions: Use of dexamethasone improved mortality in severely ill COVID-19 patients
(those receiving mechanical ventilation or requiring oxygen)
RECOVERY trial Investigators, NEJM 2020
15. Let’s break that down
15
27%=87
37%=473
- Assuming women (N=2338)
were distributed relatively
equally between
dexamethasone and usual
care groups this would
mean……
- Possibly insufficient numbers
of women to determine
whether dexamethasone
treatment was as effective in
women, particularly those who
were ventilated
16. Take home message
16
- Women and men may be more (or less) likely to acquire severe forms of disease
- Where treatment effects are dependent on disease severity, true effects in women and men
may be masked if;
1. Sex-disaggregated analyses are not performed in appropriate subgroups
2. Insufficient numbers of the lesser impacted sex are included
19. - Double-blind randomised controlled trial of daily 7-days IV hydrocortisone (200mg) vs. placebo in
3800 patients with septic shock
- Primary outcome 90 day mortality
- Secondary outcomes; time to resolution of shock, recurrence of shock, length of ICU stay, length of
hospital stay, frequency and duration of mechanical ventilation and RRT, onset of new
bacteraemia, receipt of blood transfusions
Conclusions: Hydrocortisone did not improve 90-day mortality, but patients assigned hydrocortisone
had faster resolution of shock, spent less time on a mechanical ventilator, had a shorter duration of
ICU stay.
Venkatesh et al, NEJM 2018
20. - Assessment of ADRENAL secondary outcomes separately for women and men, after
adjustments
- To compare treatment effects in women and men separately
- To assess differences between women and men; differences in mean differences,
ratio of odds ratio and ratio of hazard ratios
Thompson et al, ICM 2021
22. Conclusion: In the ADRENAL trial hydrocortisone produced beneficial effects on some
secondary outcomes in men but not women. Sex-specific treatment effects should be
examined in other critical care trials.
Thompson et al, ICM 2021
23. Recommendations
Researchers: ensure gender diversity in the research team
Journals: adopt the SAGER guidelines & create a mechanism to be
accountable
Funders: require applicants to explain how sex and gender is
accounted for