Identification of the predictors of cognitive impairment in patients with cancer in palliative care: a prospective longitudinal analysis.

PURPOSE: Studies with neuropsychological assessments in patients with cancer are sparse, and the evidence is very limited regarding their status of cognitive function over time. This study aimed at assessing the prevalence and predictors of cognitive impairment in patients with cancer in palliative care. METHODS: Prospective longitudinal investigation derived from the European Palliative Care Cancer Symptom study (2011-2013) including patients with cancer in palliative care, ≥18 years, and with at least one assessment post-inclusion. For cognitive assessment, a 4-item version of the Mini Mental State Examination was applied at inclusion and after 4 to 16 weeks. Logistic regression model with multiple imputations was applied. RESULTS: The sample consisted of 1568 patients (50% male, mean age 65.5, 42% with 10-12 years schooling, mean Karnofsky Performance Status-KPS 68%). Longitudinal analysis of the patients with complete MMSE at both assessments (n = 801) showed that 64.5% were not impaired, 12.5% remained cognitively impaired, 11.4% developed impairment, and 11.6% improved. Those who improved cognitively also reported reduced pain intensity and increased appetite. The predictive model (n = 1351) showed that those with low KPS (OR = 1.6, 95% CI 1.0-2.5) most often developed cognitive impairment, while patients with breast cancer (OR = 0.4, 95% CI 0.2-0.7) had lower odds for impairment. CONCLUSIONS: During palliative care, a substantial number of patients remained cognitively impaired or developed cognitive impairment; however, it is noteworthy that improvement was also observed. Physical performance and cancer type may predict cognitive impairment.