New study shows sex impacts blood vessel health in people with CF
Variations may help explain sex-specific differences in survival outcomes
Written by |
Among people with cystic fibrosis (CF), certain measures of blood vessel health — especially regarding the aorta, the body’s main artery — tend to vary according to biological sex, a new study reports.
Researchers think these variations may help explain sex-specific differences in survival outcomes among people with CF, but they cautioned that more work is needed to validate and expand upon these findings.
Specifically, the scientists found female CF patients “exhibit greater aortic stiffness,” or a loss of elasticity in the aorta, compared with males. According to the team, this affects the so-called vascular age of patients, which measures the biological age of blood vessels compared to a person’s chronological age.
“These findings provide critical insight into vascular aging and the role of sex in CF disease progression,” the team wrote.
The study, “Evidence of sex-related differences in vascular health among people with cystic fibrosis,” was published in the journal Respiratory Medicine. The work was funded by the Cystic Fibrosis Foundation.
CF affects people of all sexes, but disease outcomes differ based on biological sex. Indeed, data indicate that female patients with CF consistently have worse survival outcomes than their male counterparts.
The reasons for these differences, however, are not well-understood.
Investigating CF impact on blood vessels by biological sex
Cardiovascular disease — that is, disease affecting the heart and blood vessels — is the most common cause of death in the general population worldwide. Cardiovascular issues are usually not a primary manifestation of CF, but there are emerging data that the disease may impact blood vessel health.
Whether these impacts vary by biological sex has not been clear, so a team of scientists in the U.S. conducted a battery of blood vessel health tests in 22 CF patients — 12 male and 10 female — to learn more.
“Despite the established sex differences in CF-related outcomes and the emerging evidence of vascular and cardiac dysfunction in CF, whether or not sex differences in vascular health are present in people with CF remains to be explored. Thus, the present study sought to determine if sex differences in vascular health exist between males and females with CF,” the scientists wrote.
The results show the answer to that question may be yes, according to the team.
The study findings indicated that female CF patients had significantly stiffer aortas than male patients. The aorta is a large blood vessel responsible for carrying oxygen-rich blood from the heart out to the body.
These data “demonstrate that CF [disease characteristics] may have a greater negative impact on arterial stiffness in females compared to males,” the researchers wrote, noting that stiffer arteries are associated with a higher risk of issues such as high blood pressure.
Female patients with CF also had a more pronounced response to cutaneous acetylcholine — a test in which a signaling molecule that makes blood vessels widen is applied to the skin. This “may reflect underlying differences in endothelial [blood vessel cell] signaling pathways,” the researchers wrote, highlighting an opportunity for further research.
Other tests of cardiovascular health showed no significant differences between male and female patients, the team noted.
More research needed on ‘sex disparities’ in CF
The researchers stressed that this study was limited to fewer than two dozen patients assessed at one point in time and at a single site, so much more work is needed to better understand how CF affects cardiovascular health, how this differs by biological sex, and if these differences may contribute to sex-specific differences in survival.
“Although the present findings provide the foundation, it is important to note that larger studies … are certainly warranted,” the team wrote.
The researchers also noted that, “as survival in CF increases, future longitudinal studies of arterial stiffness over time are warranted to determine whether increases in [cardiovascular disease] risk can help explain the observed CF-related sex disparities in clinical outcomes.”
This new evidence “extend CF cardiovascular literature by demonstrating that vascular dysfunction in CF … appears to differ meaningfully between males and females,” the team wrote.
