Exploring medication-related hospital admissions and their association with cognitive impairment among acutely admitted older people

Abstract

Introduction: Medication-related hospital admissions (MRAs) are common among older people. Persons with cognitive impairment are especially vulnerable to adverse drug effects. At the same time, increased home health care and social support could theoretically prevent medication-related problems. This study aims to estimate the proportion of MRAs and explore their relationship with cognitive impairment in a population of acutely admitted older people.

Methods: This cross-sectional study comprised 300 individuals aged 75 years or older admitted to an acute medical ward. Two assessors identified possibly MRAs using the Assessment Tool for Hospital Admissions Related to Medications 10 (AT-HARM10). Screening for cognitive impairment was performed during ward stay using a 4-item test related to time orientation. Prevalence odds ratios between cognitive test scores and MRAs were analysed through logistic regression.

Results: Using AT-HARM10, 108 out of 300 admissions (36%) were classified as possibly MRAs by both assessors. Moreover, MRAs were least common among patients with the lowest cognitive test scores. There was an association regarding MRAs when the lowest test score was treated as a cut-off and compared against a reference category comprising all other scores (OR, 0.31 [95% CI 0.10-0.93]; p = 0.037) in a logistic regression model adjusted for cohabitation and home health care.

Conclusion: Approximately one-third of the hospital admissions among acutely admitted older people were considered at least possibly medication-related. Hence, there is still a great need to manage medication-related problems and reduce MRAs in this vulnerable population. Using a 4-item instrument to screen for cognitive impairment, there was a negative association between MRA and lowest cognitive test score. Further exploration of the relationship between MRAs and cognitive impairment may indicate appropriate components and target populations for interventions that aims to reduce the risk of MRA.

Keywords: Cognitive impairment; Hospital admissions; Medication-related problems; Older people.