Chronic kidney disease (CKD) can affect anyone, no matter their age, gender, race, or ethnic background. Some research has shown that the risk for CKD is slightly greater in women than in men – 14% women versus 12% men.
Gender differences continue to exist around the world in access to education, medical care, and participation in clinical studies. Pregnancy is a unique state for women, offering an opportunity for diagnosis of kidney disease, but also a state where acute and chronic kidney diseases may manifest, and which may impact future generations with respect to kidney health.
There are various autoimmune and other conditions that are more likely to impact women. Women have different complications on dialysis than men, and are more likely to be donors than recipients of kidney transplants.
UTIs and kidney infections are more common in women
Urinary tract infections (UTIs) lead to nearly 10 million healthcare visits each year and, if not treated early, the germs can travel up to the kidneys and cause a worse type of infection, called pyelonephritis (pie-yeh-low-nef-right-us). UTIs and kidney infections are more common in women and the risk increases in pregnancy.
Women have added risks for CKD
Women’s health is unique. One thing we know for certain is that women of child-bearing age face different problems than men when it comes to kidney disease.
Women with Chronic Kidney Disease (CKD) are generally discouraged from using “the pill” as a birth control method due to a greater chance for an increase in blood pressure and blood clots that can make kidney disease worse.
Non-pregnancy
Even women without CKD may be at risk during both pregnancy and birth because of pre-eclampsia and other problems that increase blood pressure and put a strain on the kidneys. Prenatal care is therefore crucial for all pregnant women for this very reason.
Pre-eclampsia and high blood pressure when pregnant can lead to kidney failure and the risk for CKD later in life.
Pregnancy
Pregnancy is a unique challenge and is a major cause of acute kidney injury (AKI) in women of childbearing age; AKI and pre-eclampsia (PE) may lead to subsequent CKD.
CKD has a negative effect on pregnancy even at very early stages. The risks increase with CKD progression thus posing potentially challenging ethical issues around conception and maintaining pregnancies.
Autoimmune Disease
Specific systemic conditions like Systemic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA), and Systemic Scleroderma (SS), are more likely to affect women than men. We do not know the relative contribution of these acute and chronic conditions on progression to end-stage renal disease (ESRD) in women.
Women with CKD have a higher cardiovascular risk than women without CKD; but their risk is still lower than that of men with similar degrees of kidney impairment.
Women are more likely to donate kidneys for transplantation than to receive them. We do not know if this is because of the differential incidence of CKD in men vs women, cultural factors, or other reasons.
Dialysis and transplantation
Fertility is reduced in women in dialysis compared to the general population.
Fertility is partly restored after kidney transplantation. However, even in an ideal situation (normal kidney function, no hypertension or proteinuria, at least 2 years after transplantation, without recent rejection episodes), the risk of complications is higher in women with transplanted kidneys than in the general population.
Sex Difference in Dialysis
At least 2.284 million people may have died prematurely due to lack of access to dialysis with treatment gaps being much larger in low-income countries, with conservative estimates in Asia and Africa of 1.907 million and 432,000 people not receiving dialysis.
Studies in Africa show that men were more likely to receive dialysis than women. In Japan, the incidence of being treated with dialysis in females was less than half of that in males (3287 in males vs. 1764 women per million population treated). One US study reports women having significantly higher rates for late initiation of dialysis compared to men. Awareness levels of previous kidney disease in women were reported much lower than in men (2.9% ± 1.6% in women vs. 17.9% ± 5.9% in men), which may contribute to later initiation of dialysis.
Mortality rates are similar in men and women on dialysis, but the incident rates of some dialysis-associated complications and morbidity are higher in women. A US report of hospitalizations in 111,653 patients undergoing maintenance hemodialysis describes higher hospitalization rates in women, and higher risk for 30-day readmissions.
In addition, the prevalent use of arteriovenous fistula, which is associated with reduced mortality, complication, and costs, is lower among female than male hemodialysis patients. This may be due to a number of different factors, including anatomical/surgical issues relating to vessel size, timing of referral, and attitudinal differences.
Women receiving dialysis have also been reported to have worse clinical parameters including anemia, nutrition, and quality of life.
Sex differences in transplantation
Transplantation represents the best form of treatment in patients without contraindications. Worldwide data describes that women are less likely than men to be kidney transplant recipients, either from a cadaveric or living donor, but are more likely to serve as living donors for kidney transplantation.
Data from different countries, including the US, France, China, and India, confirm differential kidney transplant rates (lower in women than men), less likelihood of women being registered on national transplant waiting lists, and longer time from dialysis initiation to listing.
Mothers are more likely to be donors, as are female spouses. Sex inequality also exists in the pediatric population. A survey from 35 countries participating in the European Society for Pediatric Nephrology/European Renal Association-European Dialysis and Transplant Association Registry, reported girls had a lower access to renal transplantation than boys.
Socioeconomic factors undoubtedly play a role in the inequality of transplantation between sexes, especially in the low and middle-income countries and regions.
Generally, men provide the major income for their family which may discourage them to donate kidneys. Different employment status and incomes between genders may contribute to sex differences in transplantation because employment and income status is usually associated with better healthcare insurance which cover the costs for transplantation.
US data found black women were less likely to want living donor kidney transplantation compared with men, despite being twice as likely as men to receive unsolicited offers for kidneys. They were also less likely to have been evaluated for a kidney transplant.
Other reports describe disparities in age and sex in access to kidney transplantation which originate at the time of pre-referral discussions about kidney transplantation; irrespective of age, women were more likely not to have had discussions with medical professionals.
Summary
Women have unique risks for kidney diseases: kidney diseases, as well as issues related to access to care, have a profound impact on both the current and next generations. Advocating for improved access to care for women is critical to maintain the health of families, communities, and populations.
Focused studies on the unique contribution of sex hormones, or the interaction of sex hormones and other physiology, is important to improve our understanding of the progression of kidney diseases. Immunological conditions such as pregnancy (viewed as a state of tolerance to non-self) as well as SLE and other autoimmune and systemic conditions common in women, better studied may also lead to breakthroughs in understanding and care plans.
There is a clear need for higher awareness, timely diagnosis, and proper follow up of chronic kidney disease in pregnancy. In turn, pregnancy may also be a valuable occasion for early diagnosis of chronic kidney disease, allowing planning of better therapies.
