Chronic kidney disease (CKD) and cognitive impairment are often treated as separate clinical concerns. However, the latest research shows that the two are more connected than clinicians might think.
A new study published in JAMA Network Open suggests that the severity of CKD is linked to a higher risk of cognitive impairment, particularly in attention, processing speed, and executive function. The findings underscore how kidney health metrics (eGFR and proteinuria) could provide key insights into an older adult’s future cognitive function.
The research is particularly relevant to Black patients, who are over three times more likely to develop kidney failure than white Americans. This disparity reflects longstanding structural inequities and social determinants of health (SDOH) that disproportionately affect Black communities. As a result, Black communities have significantly higher rates of hypertension, diabetes, obesity, and heart disease—all of which are risk factors for kidney disease.
For providers, understanding the overlap is crucial to improving long-term outcomes for Black patients.
Study Overview
For patients with chronic kidney disease (CKD), the severity of CKD is associated with an increased incidence of cognitive impairment, according to a study published online Feb. 17 in JAMA Network Open.
Zhijie Huang, Ph.D., from the Tulane University School of Public Health and Tropical Medicine in New Orleans, and colleagues examined associations between CKD severity based on the estimated glomerular filtration rate (eGFR) and urinary protein-to-creatinine ratio (UPCR) and incident cognitive impairment in a study involving 5,607 participants with CKD.
The researchers found that each 1 standard deviation (SD) higher log-transformed UPCR was associated with an increased risk for impairments in attention and processing speed and impairment in executive function (hazard ratios, 1.21 and 1.16, respectively) in multivariable-adjusted analyses. Each 1 SD lower eGFR was associated with an increased risk for impairment in attention and processing speed (hazard ratio, 1.21). After further adjustment for eGFR, findings for UPCR remained nominally significant, while eGFR findings were attenuated with adjustment for UPCR. Compared with those with an eGFR of 60 mL/min/1.73 m2 or more and UPCR less than 150 mg/g, patients with a combined eGFR less than 60 mL/min/1.73 m2 and UPCR of 150 mg/g or more had a significantly increased risk for impairment in global cognition (hazard ratio, 1.38).
“More advanced proteinuria was significantly associated with impairments in attention and processing speed as well as executive function,” the authors write. “Although a decreased eGFR was also associated with attention and processing speed, proteinuria largely explained this association.”
Two authors disclosed ties to the biopharmaceutical industry.
Vascular Health and Shared Risk Pathways
CKD and cognitive impairment share several overlapping mechanisms through the kidney-brain axis, which involve:
- Chronic inflammation
- Hypertension-related brain changes
- Microvascular damage
- Uremic toxic buildup
Because Black patients can experience higher rates of uncontrolled hypertension and vascular disease, these shared pathways may place them at a compounded neurologic risk as CKD progresses.
Cognitive changes to executive function, attention, and processing speed can directly impact a patient’s ability to:
- Manage medications
- Adhere to dialysis schedules
- Follow dietary restrictions
- Monitor blood pressure or glucose
- Navigate complex insurance systems
For Black patients who may already face several systemic barriers, even minor cognitive impairment could accelerate health disparities.
Clinical Implications for Healthcare Providers Serving Black Patients With Chronic Kidney Disease
The study suggests that patients with an eGFR <60 mL/min/1.73 m2 and UPCR ≥150 mg/g may require closer cognitive monitoring.
Several practical strategies can help clinicians mitigate risk and support patients more effectively.
These include:
Considerations for Screening
For clinicians serving Black populations, this may mean:
- Earlier screening for cognitive changes in moderate CKD.
- Implementing brief executive function tools in nephrology.
- Monitoring patients with significant proteinuria more closely.
Communication Strategies
If you suspect cognitive decline is present, you can:
- Use plain language when delivering medical guidance.
- Confirm they understand through teach-back.
- Provide written summaries of what was covered during the visit.
- Involve family members or caregivers when appropriate.
Multidisciplinary Care
High-risk CKD patients may benefit from the following types of care:
- Social work support
- Nutritional counseling
- Nephrology and primary care collaboration
- Referral to neurology when appropriate
Structural and Policy Considerations
Since the severity of chronic kidney disease can drive cognitive risk, healthcare professionals and public health professionals can better address the health inequities Black patients face by:
- Expanding hypertension and CKD screening through trusted community settings, such as churches, community health centers, and barber shops.
- Improving access to urine protein testing.
- Reducing delays in referrals to nephrology.
The SDOH must also be addressed, as transportation barriers, fragmented care, and financial strain can keep some Black patients from getting quality medical care. Interventions must extend beyond laboratory metrics to get better outcomes.
Bottom Line
Chronic kidney disease severity—particularly proteinuria—is linked to a higher risk of cognitive impairment. Black patients have a disproportionate burden of CKD and vascular disease, and cognitive decline may further complicate disease self-management, thus widening already existing disparities.
Early cognitive screening, culturally responsive communication, and multidisciplinary collaboration may help reduce downstream complications and narrow disparities in this high-risk population.