Prevalence of delirium, depression and dementia among elderly medical inpatients of a tertiary care hospital of Sri Lanka

Background: Delirium, depression and dementia are highly prevalent neuropsychiatric conditions among older adults, and have a huge impact on quality of life, morbidity and mortality.

Objectives: This study aimed at determining the prevalence of delirium, depression, and dementia among elderly medical in-patients admitted to the National Hospital of Sri Lanka. The other objectives were to describe the associations of delirium, depression, and dementia, and to determine the rate of identification by the treating team.

Materials and methods: A cross-sectional descriptive study was conducted among 234 elderly patients admitted to the National Hospital of Sri Lanka. The participants were screened using Sinhala and Tamil versions of Confusion Assessment Method (CAM), Geriatric Depression Scale (GDS) and Montreal Cognitive Assessment (MoCA), and those who screened positive were subsequently assessed with Diagnostic and Statistical Manual (DSM) 5 criteria.

Results: Sixty five percent were females, and the mean age was 69.47 (SD + 7.087). Forty two participants, (17.9%, 95% CI 13.3-22.5) screened positive and fulfilled DSM criteria for delirium. Fifty One (25.5%) screened positive with GDS and forty-seven (23.5%, 95% CI 17.8-30) were depressed according to DSM5. MoCA scores were positive for cognitive impairment in 130 (72.63%) and the prevalence of dementia was 14.53% (95% CI 9.7-20.6). A statistically significant association was seen for delirium with age and medical comorbidity, for dementia with age, and for depression with marital state and living circumstances. Only 17 (16.19%) out of a total of 105 cases were identified by the treating team, and 1.9 % were referred to psychiatric services.

Conclusions: A significant proportion of older medical in-patients have delirium, depression and dementia, and only a small proportion is identified. It is prudent that medical staff are adequately trained to identify these conditions and liaison psychiatry services are available.