Health outcomes in chronic kidney disease patients with cognitive impairment or dementia: a global collaborative analysis.

Background and hypothesis: Mild cognitive impairment and dementia (CI) are common in patients with CKD. We aim to clarify whether and how CKD and CI coexistence increases adverse health outcomes. Methods: This retrospective observational cohort study was conducted on CKD patients (stages 3-5) from the TriNetX platform. CKD patients with and without pre-existing CI were included from 115 healthcare organizations, and their outcomes were compared. The two cohorts were propensity score matched (PSM) for age, sex, ethnicity, comorbidities, BMI, blood parameters, and medications. The proportional hazard assumption was tested with a 95% confidence interval. Kaplan-Meier analysis was used to calculate survival probability. Outcomes were included from 1 day after the CKD diagnosis until 10 years afterwards. Results: We identified 533 772 CKD patients, and 8184 had co-existent CI. Two cohorts of 8170 PSM patients each were generated. The mean age was 60.5 ± 7.0 years and the eGFR was 52.1±19 mL/min. Mean follow-up was 23.2 months. CKD patients with CI had higher all-cause mortality (18.5% vs 12.6%), higher risk of cerebrovascular disease (11.3% vs 6.9%), transient cerebral ischemic attacks (2.7% vs 1.6%), hypotension (16.5%-12.5%), malnutrition (6.7% vs 4.0%), pneumonia (10.7% vs 7.9%), urinary infections (13.2% vs 9.3%), encephalopathy (9.9% vs 5.0%), mood disorders (13.6% vs 9.7%), psychosis (9.8% vs 4.6%), and epilepsy (4.3% vs 1.5%). Higher use of antidepressants (26.3% vs 16.3%), anticonvulsants (19.5% vs 15.1%), antipsychotics (18.6% vs 9.1%), anticholinesterase (5.6% vs 0.1%), and benzodiazepines (30.6% vs 26.6%) was noted in those with CI. All these findings were statistically significant. Conclusion: Despite the limitations of a retrospective study, real-world data demonstrate that concomitant CI is a decisive risk factor for higher mortality and increased adverse outcomes in patients with CKD. These results highlight the need for routine comprehensive cognitive assessments in patients at any stage of CKD.