Cognitive Function and All-Cause Mortality in Maintenance Hemodialysis Patients

Abstract

Background Cognitive impairment is common in hemodialysis patients and associated with significant morbidity. Limited information exists on whether cognitive impairment is associated with survival, and whether type of cognitive impairment is important. Study Design Longitudinal cohort. Setting & Participants Cognitive function was assessed at baseline and yearly using a comprehensive battery of cognitive tests in 292 prevalent hemodialysis patients. Predictor Using principal component analysis, individual test results were reduced into 2 domain scores, representing memory and executive function. By definition, each score carried a mean of 0 and SD of 1. Outcomes Association of each score with all-cause mortality was assessed using Cox proportional hazards models adjusted for demographics as well as dialysis and cardiovascular (CV) risk factors. Results Mean age of participants was 63 years, 53% were male, 23% were African American and 90% had at least a high school education. During median follow up of 2.1 (IQR, 1.1–3.7) years, 145 deaths occurred. Each 1-SD better executive function score was associated with 35% lower hazard of mortality (HR, 0.65; 95% CI, 0.55–0.76). In models adjusting for demographics and dialysis-related factors, this relationship was partially attenuated but remained significant (HR, 0.81; 95% CI, 0.67–0.98), while adjustment for CV disease and heart failure further attenuated it (HR, 0.87; 95% CI, 0.72–1.06). Use of time-dependent models showed a similar unadjusted association (HR, 0.62; 95% CI, 0.54–0.72), with the relationship remaining significant after adjustment for demographics, dialysis, and CV risk factors (HR, 0.79; 95% CI, 0.66–0.94). Better memory was associated with lower mortality in univariate analysis (HR per 1 SD, 0.82 [95% CI, 0.69–0.96]), but not when adjusting for demographics (HR, 1.00; 95% CI, 0.83–1.19). Limitations Patients with dementia were excluded from the full battery, perhaps underestimating strength of the association. Conclusions Worse executive function and memory are associated with increased risk of mortality. For memory, this association is explained by patient demographics, while for executive function this relationship may be partly explained by CV disease burden.

Dementia, Alzheimer’s Disease, and Mortality after Hemodialysis Initiation

“…Among older patients on hemodialysis, dementia likely exists on a spectrum, influenced by both vascular processes as well as the Alzheimer's disease pathology, although the former process is likely more common (38)(39)(40)(41).…”

Cognitive Impairment and Risk of All‐Cause and Cardiovascular Disease Mortality Over 20‐Year Follow‐up: Results From the BLSA

“…The findings of previous studies on sex differences between cognitive function and mortality have been inconsistent 5, 15, 25. Perna et al showed that the association between low COGTEL (Cognitive Telephone Screening Instrument) total scores and all‐cause mortality was much stronger among men than in women 15.…”

Afectación Neuropsicológica de la Función Ejecutiva en Pacientes con Insuficiencia Renal Crónica

“…Inicialmente suele ser una condición asintomática y el diagnóstico puede ser sugerido por la asociación de manifestaciones inespecíficas por parte del paciente, como fatiga, pérdida de peso, picazón, hipertensión, hemólisis, poliuria entre otras. En la fase final, se llegan a observar anomalías de laboratorio y alteraciones clínicas importantes, preparando al paciente para el tratamiento de sustitución renal, diálisis o trasplante (Drew et al, 2015). En muchos sujetos con IRC, ya son conocidas enfermedades renales previas u otras condiciones clínicas subyacentes; y en un número pequeño, la causa es desconocida.…”

“…Estos trastornos cognitivos que cursan en dirección al deterioro cognitivo en los pacientes con hemodiálisis y diálisis peritoneal, es una condición aún poco reconocida como una carga importante de salud pública (Wei et al, 2014). Estos déficits cognitivos se asocian con problemas en los sistemas de memoria, el lenguaje y la función ejecutiva (Davey, Elias, Robbins, Seliger, & Dore, 2013), siendo esta última, el proceso neurocognitivo más comprometido por la insuficiencia renal (Drew et al, 2015).…”

“…Funciones estrechamente asociadas a regiones prefrontales, dorsolaterales y anteriores, encargadas, entre otras cosas, de la velocidad de respuesta, la flexibilidad y el control cognitivo, la mentalización, la planificación y la solución de problemas (Stuss & Knight, 2012). Por tanto, la alteración de la función ejecutiva llega a afectar el desempeño neuropsicológico, el bienestar y la calidad de vida del paciente, generando mayores dificultades con la adherencia al tratamiento y aumentando el riesgo de morbimortalidad (Drew & Weiner, 2014;Drew et al, 2015).…”