Prevalence of Cognitive Impairment Among Elderly Chinese Continuous Ambulatory Peritoneal Dialysis Patients

Abstract

To determine the prevalence and attributes of cognitive impairment in elderly continuous ambulatory peritoneal dialysis (CAPD) patients. The Cantonese version of the Mini-Mental State Examination (CMMSE) was used to assess the cognitive function of 81 elderly CAPD patients and 66 healthy elderly (age ≥ 65 years). The maximum score is 30, with a higher score indicating better cognitive performance. Other study variables included demographic data, duration of dialysis, dialysis adequacy (Kt/V), albumin and hemoglobin levels, comorbid medical conditions, days of hospital stay, and episodes of peritonitis and exit site infection. The CAPD group had lower CMMSE scores than the healthy elderly group ( p < 0.001); 32.1% of CAPD patients and 7.6% of the healthy elderly were identified as cognitively impaired according to CMMSE cutoff points ( p < 0.001). Logistic regression revealed that increased age (odds ratio, OR, 1.1; 95% confidence interval, 95% CI, 1.02-1.3; p = 0.018) and female gender (OR, 3.3; 95% CI, 1.1-9.9; p < 0.03) were significantly and positively associated with cognitive impairment. Protective factors included years of education (OR, 0.78; 95% CI, 0.65–0.94; p < 0.009). After adjusting for the effects of age, gender and education, CAPD patients were at greater risk for cognitive impairment than the healthy elderly (OR, 7.7; 95% CI, 2.4-24.8; p < 0.001). Education was positively correlated with CMMSE score ( r = 0.52; p < 0.001), while days of hospital stay showed an inverse relationship ( r = −0.243; p = 0.03). The duration of dialysis, Kt/V, albumin and hemoglobin levels, and the number of comorbid conditions were not correlated with CMMSE score. There is a high prevalence of cognitive impairment in elderly CAPD patients. It is imperative that a cognitive screening test be incorporated into nursing assessments for early detection of cognitive changes.