Cognitive Disorders Assessment in Chronic Hemodialysis Patients According to the Mini-Mental State Examination (MMSE) and the Senegal Test

Introduction: Dementia is a common disorder and occurs sometimes as an early conditionin chronic hemodialysis patient. The prevalence in this population is very variable, reaching up to 87% in some studies. In black Africa, data related to cognitive disorders in chronic hemodialysis patients are scarce. The objectives of this study were to measure the prevalence of these disorders in this population based on 2 cognitive tests (MMSE and Senegal test), to analyze clinical-biological patterns and to identify associated factors tocognitive impairement.

Patients and Methods: We conducted a cross-sectional, descriptive and analytical study during the period range from February to March 2017 at hemodialysis unit of Aristide Le Dantec University Hospital. All patients over 18 years who have undergone hemodialysis for more than 3 months were included.We used two cognitive tests: the Mini-Mental State Examination (MMSE) and the Senegal test. Cognitive decline was defined by a score <24/30 according to MMSE and <28/39 according to Senegal test.

Results: Sixty chronic hemodialysis patients were studied whith a mean age of 50.98 ± 13.42 years,and male predominance (33 men for 27 women, a sex ratio of 1.22). The age group range from 30 to 54 was the most represented in 55%.Twenty-eight patients, standing for 46.7% of the population studied, were out of school and 33 patients (55%) had a low socio-economic level. Hypertensive nephropathywas found in 50% of cases, chronic glomerulosclerosis was found in 16.7% of cases. Nine patients (15%) had a history of aluminum intoxication. Mean dialysis duration was 79.85 ± 41.4 months. Patients had an average of 11.7 ± 1.02 hours of dialysis per week. Mean KT / V was 1.25% ± 0.16. Mean hemoglobin level was 9.47 ± 2.55 g / dl. Thirty-nine patients (65%) benefited from antihypertensive treatment. the prevalence of MMSE cognitive decline and the Senegal test were respectively 11.7% and 5%. Mean MMSE score was 26.57 ± 2.39 with extremes range from 21/30 to 30/30. As for the Senegal test, the average score was 33.27 ± 3.12 with extremes range from 21/39 to 37/39.
In bivariate analysis, there was a statistically significant relationship between female gender, low diastolic blood pressure, and the occurrence of cognitive impairment according to the MMSE results. Regarding the Senegal test, although the number of patients with cognitive impairment is low (3/60), we can see a statistically significant correlation between the onset of cognitive impairment and the advanced age of the patients, a history of stroke and low diastolic blood pressure. However, in our study, no link was established between low cognitive scores and the level of school, physical inactivity, biological parameters and treatments received in hemodialysis patients.

Conclusion: The prevalence of cognitive decline in our population was lower according to the Senegal test. But it is essential to detect a cognitive decline in hemodialysis patient as soon as possible in order to plan an appropriate management strategy.