Time for increased awareness of sex as a biological variable in transplantation

Sex difference and immunosenescence affect transplantation outcomes

Kidney transplantation is a well-established alternative to renal replacement therapy. Although the number of patients with end-stage renal disease (ESRD) is increasing, the availability of kidney for transplantation is still insufficient to meet the needs. As age increases, the prevalence of ESRD increases; thus, the population of aged donors and recipients occupies large proportion. Accumulated senescent cells secrete pro-inflammatory factors and induce senescence. Additionally, it is gradually becoming clear that biological sex differences can influence aging and cause differences in senescence. Here, we review whether age-related sex differences affect organ transplant outcomes and what should be done in the future.

Female sex and advanced age are associated with invasive cytomegalovirus disease in solid organ transplant recipients

BACKGROUND

Limited data exist to describe sex-based differences in the severity of cytomegalovirus (CMV) infection after solid organ transplant (SOT). We sought to identify if a difference exists in likelihood of tissue-invasive disease between male and female SOT recipients and to understand how age affects this relationship.

METHODS

A retrospective cohort of 180 heart, liver, and kidney recipients treated for CMV was examined. A logistic regression model was developed to assess the relationship between female sex and CMV type (noninvasive vs. invasive). A secondary regression analysis looked at the relationship of invasive CMV with a variable combining sex with age above or below 50.

RESULTS

There were 37 cases of proven or probable invasive CMV, occurring in 30% of females versus 16% of males. After adjustment for potential confounders, females with CMV infection were significantly more likely to have invasive disease (odds ratio (OR) 2.69, 95% confidence interval (CI) 1.25-5.90, p = .01). Females 50 years or older were at particular risk compared with males under 50 years (adjusted OR 4.54, 95% CI 1.33-18.83, p = .02).

CONCLUSION

Female SOT recipients with CMV in our cohort were more likely than males to have tissue-invasive disease, with the highest risk among older females. Further prospective studies are warranted to explore underlying immunologic mechanisms.