Charlson Comorbidity Index, inappropriate medication use and cognitive impairment : Bermuda Triangle

The aim is to evaluate the association between the Charlson Comorbidity Index (CCI), polypharmacy, inappropriate medication use and cognitive impairment in long-term care facility patients.

A cross-sectional study including 105 long-term care facility residents was performed. The Charlson Comorbidity Index (CCI) was used. Inappropriate drug use (IDU) was defined according to the STOPP (Screening Tool of Older People's Prescriptions) criteria. Univariate analysis to identify variables associated with patient outcome related with cognitive impairment was investigated with χ², Pearson correlation, Fisher exact, and Mann-Whitney U test where appropriate. For the multivariate analysis, the possible factors identified with univariate analysis were further entered into logistic regression analysis.

A significant difference was found between gender, CCI and cognitive impairment (p = 0.038, p = 0.01). While every one point increment in the CCI increases the risk of cognitive impairment 3.1 fold (95% CI = 1.8-5.4, p < 0.001), hypertension increases the risk 12 fold (95% CI = 2.5-67.8, p = 0.002). While the correlation between Mini-Mental Status Examination (MMSE) score and polypharmacy is significant (p = 0.015), the correlation between MMSE and IDU was insignificant (p = 0.739). The association of urogenital system drugs and dementia was significant (p = 0.044).

Comorbidities, especially hypertension and old age, are risk factors for cognitive impairment. Polypharmacy correlates with MMSE and is considered a risk factor for cognitive impairment. Inappropriate medication use is high among long-term care facility residents. More studies on large cohorts are needed regarding optimal drug prescription and detection of specific drugs that may have an impact on cognitive performance.