Key takeaways:

• Diabetic kidney disease accounted for 16% of cases among women with CKD globally.
• Women aged 15 to 49 years face increasing risks for CKD due to metabolic factors and dietary behaviors.

Globally, 359 million women are living with chronic kidney disease, with increasing ties to metabolic diseases and CVD, according to study data published in Chinese Medical Journal.

Previous studies have identified the global prevalence of CKD overall. However, the prevalence of CKD and associated risk factors among women is not well understood, according to Lin Sun, MD, PhD, professor in the department of nephrology, Chongbin Liu, MD, both at The Second Xiangya Hospital of Central South University, China, and colleagues.

Globally, about one-third of women with CKD are of reproductive age. Image: Adobe Stock

“Most global epidemiology pools men and women together, so the pattern [of CKD] in women disappears into the average,” Sun and Liu told Healio. “Additionally, women accumulate kidney risk in ways men do not, such as with preeclampsia and other adverse pregnancy outcomes, which substantially raise the long-term risk of CKD and kidney failure.”

Using data from the 2021 Global Burden of Disease study, the researchers aimed to evaluate the prevalence of CKD among women between 1990 and 2021.

The primary indicators assessed were disease prevalence, mortality and disability-adjusted life-years. Risks factors for CKD, including dietary and behavioral factors, metabolic risk factors and environmental and occupational factors were also evaluated.

Results showed that 359 million women had CKD globally, a 90.65% increase compared with 188 million women living with CKD in 1990, according to the researchers. Population growth (58.63%) and aging (26.64%) were the primary drivers of the increase in disability-adjusted life-years.

In addition, about 16% of CKD cases and more than one-third of CKD-related deaths were tied to diabetic kidney disease.

“Deaths rose by about 181%,” Sun and Liu said. “Much of that reflects population growth and aging rather than rising individual risk, which is why we also report age-standardized rates. Either way, the number of women a health system has to look after has nearly doubled.”

CVD made up 46.7% of the total disease burden of CKD attributable to impaired kidney function. Ischemic heart disease made up the largest share of the CVD burden (60.4%), followed by intracerebral hemorrhages (19.6%) and ischemic stroke (18.7%).

The primary risk factors increasingly associated with the rising CKD burden for all ages included high fasting glucose (48.83%), high systolic blood pressure (32.76%) and high BMI (78.61%). Notably, women aged 15 to 49 years, compared with women aged 50 years and older, had sharper increases in CKD linked to high fasting glucose (40.66% vs. 26.22%), high BMI (112.17% vs. 44.67%), low fruit (21.28% vs. –11.66%) and vegetable consumption (19.49% vs. –11.76%) and low physical activity (54.76% vs. –3.67%), among other factors.

Overall, about one-third of women with CKD are of reproductive age, according to the researchers.

“[The data] suggest many women begin to be exposed to CKD risk well before middle age,” Sun and Liu said.

Regions with low and low-middle sociodemographic index had the highest age-standardized disability-adjusted life-year and age-standardized mortality rates. The age-standardized CKD prevalence rates were highest in low-middle sociodemographic index regions.

The findings suggest the global number of CKD cases among women has nearly doubled since 1990, according to the researchers. Challenges related to cardiovascular-kidney-metabolic syndrome may become more prevalent over time, the researchers wrote.

“Thirty years ago, kidney disease in women was largely glomerular and infectious in origin, and it is now metabolic,” Sun and Liu said. “In practice, women with diabetes, high blood pressure or obesity should undergo kidney function testing, including during prepregnancy and prenatal examinations. At the same time, a decrease in eGFR or the presence of proteinuria should also be considered a cardiovascular finding, not just a renal finding.”

More studies should enroll women with CKD to explore the benefits of CKD treatments and understand the mechanisms of kidney function decline after menopause, according to Sun and Liu.

“We would like to see more women enrolled in trials and report honestly what happened to them — every pivotal CKD trial we rely on was built on a population that undercounted women,” Sun and Liu said. “Secondly, we would like to see mechanistic work on why kidney function declines faster after menopause. Finally, we are looking forward to a reduction in the inequality of medical resources for women.”

For more information:

Chongbin Liu, MD, can be reached at nephrology@healio.com.

Lin Sun, MD, PhD, can be reached at sunlin@csu.edu.cn.