Nephrology Patients Exhibit Frequent Depression Without Neurological Deficits
Authors: Roque Alex F. , Holmgren Nathaniel J. , Saxe Jonathan M. , Jacobson Lewis E. , West‐Sell Sharon A. , Harper Paul , Williams Jamie , Jensen Courtney D. 
Published: May 2022

INTRODUCTIONChronic kidney disease (CKD) is a progressive condition that associates with high comorbidity, and often requires complex management.PURPOSETo investigate interrelationships between kidney function, neurological deficits, and mental health in a diverse sample of nephrology patients.METHODSWe analyzed 621 patients admitted to a major midwestern hospital for acute kidney injury (AKI), CKD, or end‐stage renal disease (ESRD) between September, 2015 and July, 2018. We recorded all demographic, anthropometric, metabolic, and diagnostic information, and used this dataset to evaluate relationships within the clinical population. We also exported a comparison sample from the same hospital, consisting of 2,306 patients without kidney injury or disease. In the first dataset, there were 269 patients with a diagnosis of CKD; coarsened exact matching selected 269 patients from the comparison group, matched for both age and sex. We characterized each sample with means, standard deviations, and categorical percentages. Using the comparison data, we assessed group differences with independent‐samples t‐tests and chi‐squared tests. In the larger dataset of nephrology patients, we performed logistic regression analyses to evaluate predictors of depression, anxiety, cognitive deficits, and cerebrovascular accidents (CVA), holding potential confounders constant.RESULTSNephrology patients were 65.2 ± 17.3 yr, 50.9% were female, 41.4% were obese, glomerular filtration rate (GFR) was 28.8 ± 13.8 mL/min, 77.1% had an AKI, 43.3% had CKD, and 4.2% had ESRD. Anxiety affected 6.6%, depression affected 12.9%, 8.1% of patients had dementia or Alzheimer’s, 5.0% had encephalopathy, and 8.5% had experienced a CVA. In the logistic regression models, holding all significant confounders constant, GFR was an insignificant predictor of depression (p=0.292), anxiety (p=0.203), CVA (p=0.442), and cognitive decline (p=0.949). In alternative models, depression was not predicted by diagnosis of AKI (p=0.400), CKD (p=0.606), CKD stage (p=0.982), or ESRD (p=0.268) when substituted for GFR. Similarly, anxiety was not predicted by AKI (p=0.334), CKD (p=0.544), CKD stage (p=0.262), or ESRD (p=0.998). CVA was not predicted by AKI (p=0.231), CKD stage (p=0.228), or ESRD (p=0.401); diagnosis of CKD exhibited a trending significance, reducing the odds of CVA by 46%, holding age, sex, and body mass index constant (p=0.062; 95% CI of OR: 0.283 to 1.031). Diagnosis of dementia or Alzheimer’s was not predicted by CKD (p=0.532), CKD stage (p=0.550), or ESRD (p=0.998). Holding constant age, diagnosis of encephalopathy, history of CVA, and traumatic brain injury, AKI predicted a 3.1‐fold increase in the odds of dementia or Alzheimer’s (p=0.047; 95% CI of OR: 1.015 to 9.193). Comparisons of CKD patients to the control group matched for age and sex revealed no differences in CVA (p=0.861) or dementia (p=0.276), but depression was higher among CKD patients (13.4%) than the comparison group (2.2%; p<0.001).CONCLUSIONWhen matched for sex and age, patients with CKD or ESRD did not exhibit higher incidence of CVA or cognitive decline. However, depression disproportionately affected these patients.