The Clock Drawing Task reveals executive dysfunction in the dialysis population - an underrecognized and underestimated problem.

AIM OF THE STUDY: The study aimed to assess the prevalence of executive function impairment among patients with chronic kidney disease (CKD) undergoing dialysis, with no subjective cognitive problems and with normal global cognition on the Mini-Mental State Examination (MMSE). We also investigated the relationship between cardiovascular risk factors and cognitive test results. RATIONALE FOR THE STUDY: Patients with CKD, including those undergoing renal replacement therapy, are at a higher risk of developing cognitive impairment (CI) than the general population. Recent research has shown CI to be a growing problem among CKD patients worldwide. Yet, it remains underdiagnosed, even though it may significantly influence the lives of patients. MATERIALS AND METHODS: In this cross-sectional, prospective study, 58 dialysis patients with no cognitive decline on the MMSE screening were assessed for executive function impairment using the Executive Clock-Drawing Task (CLOX). Moreover, past medical history, demographic data, and laboratory test results were collected. RESULTS: The mean patient age was 59.47 ± 14.98 years, and the mean duration of dialysis was 45.93 ± 48.49 months. The prevalence of executive function impairment amounted to 8.6%. Moreover, remarkably similar pattern of clock drawing was observed, with numbers written outside the clock face in the CLOX1 test. CONCLUSIONS: Executive dysfunctions in dialysis patients may manifest itself before the onset of global cognitive impairment. There appear to be a deficit in the spatial domain as well. Better education may play a protective role.

Cognitive impairment in patients awaiting kidney and liver transplantation-A clinically relevant problem?

INTRODUCTION: Cognitive impairment (CI) is common in both end-stage kidney disease (ESKD) and alcohol-related liver cirrhosis. The aim of this study was to assess the prevalence and patterns of CI in patients awaiting kidney and liver transplantation, and to identify its determinants. METHODS: In this cross-sectional, prospective study, 31 consecutive patients with ESKD and 31 consecutive patients with alcohol-related liver cirrhosis, all currently on transplant waiting lists, were screened for cognitive decline using the Addenbrooke's Cognitive Examination. Medical history, demographics, and laboratory test results were also collected. RESULTS: The prevalence of CI among patients with ESKD and alcohol-related liver cirrhosis was 26% and 90%, respectively. In both groups, memory was the most affected cognitive domain, along with verbal fluency in patients with ESKD, and visuospatial abilities in patients with alcoholic cirrhosis. The most statistically significant increase in the prevalence of CI was found in patients with lower educational attainment, in both alcohol-related liver cirrhosis and ESKD populations as well as in older patients with alcoholic cirrhosis. Furthermore, better cognitive functioning in ESKD patients was associated with higher levels of total lymphocyte count and alanine transaminase (ALT), and in alcohol-related liver cirrhosis patients with higher levels of ALT and aspartate transaminase. A nonsignificant trend toward lower memory domain scores was also observed with increasing ammonia levels and increasing severity of liver disease (higher Child-Pugh scores). Finally, suboptimal performance on the screening test was correlated with the severity of liver disease as assessed by the Model for End-Stage Liver Disease Sodium (MELD-Na), but not at the statistically significant level. CONCLUSIONS: The prevalence of CI, especially in patients with alcohol-related liver cirrhosis, is high and can be a significant clinical problem, negatively affecting the transplantation process. Routine screening tests in this group would contribute to the implementation of appropriate management, such as rehabilitation program or psychosocial treatments and facilitate the provision of specialized health care.