Risk factors for incident delirium among older people in acute hospital medical units: a systematic review and meta-analysis.

BACKGROUND: delirium affects up to 40% of older hospitalised patients, but there has been no systematic review focussing on risk factors for incident delirium in older medical inpatients. We aimed to synthesise data on risk factors for incident delirium and where possible conduct meta-analysis of these. METHODS: PubMed and Web of Science databases were searched (January 1987-August 2013). Studies were quality rated using the Newcastle-Ottawa Scale. We used the Mantel-Haenszel and inverse variance method to estimate the pooled odds ratio (OR) or mean difference for individual risk factors. RESULTS: eleven articles met inclusion criteria and were included for review. Total study population 2338 (411 patients with delirium/1927 controls). The commonest factors significantly associated with delirium were dementia, older age, co-morbid illness, severity of medical illness, infection, 'high-risk' medication use, diminished activities of daily living, immobility, sensory impairment, urinary catheterisation, urea and electrolyte imbalance and malnutrition. In pooled analyses, dementia (OR 6.62; 95% CI (confidence interval) 4.30, 10.19), illness severity (APACHE II) (MD (mean difference) 3.91; 95% CI 2.22, 5.59), visual impairment (OR 1.89; 95% CI 1.03, 3.47), urinary catheterisation (OR 3.16; 95% CI 1.26, 7.92), low albumin level (MD -3.14; 95% CI -5.99, -0.29) and length of hospital stay (OR 4.85; 95% CI 2.20, 7.50) were statistically significantly associated with delirium. CONCLUSION: we identified risk factors consistently associated with incident delirium following admission. These factors help to highlight older acute medical inpatients at risk of developing delirium during their hospital stay

Apolipoprotein E epsilon4, Alzheimer\u27s disease, and cognitive performance in elderly Mexican Mestizos

Objectives: To determine the relationship between apolipoprotein E (APOE) epsilon4 and Alzheimer\u27s disease (AD) in the Mexican Mestizo population, as well as its effects on the cognitive profile of AD and elderly Mestizos without dementia. Design: Cross-sectional analysis of a cohort study. Setting: Evaluations were conducted at the geriatrics clinic of an academic medical hospital in Mexico City. Participants: Forty-nine elderly subjects with AD and 141 controls selected from a representative sample of Mexican Mestizos aged 65 to 96 who participated in the Prevalence Survey of Dementia in the Mexico City Elderly Population cohort. Measurements: All subjects underwent APOE genotypification and a comprehensive clinical and neuropsychological evaluation. Results: There were no significant differences in epsilon3 and epsilon4 frequencies between the subjects with and without AD and a tendency toward higher epsilon4 and lower epsilon3 allele frequencies in subjects aged 75 and older. No association was found between APOE epsilon4 and the presence of AD. The age-, sex-, and education-adjusted risk for AD associated with at least one epsilon4 allele was 1.01 (95% confidence interval=0.45-2.23). Performance on a long-term visual memory test was significantly worse in APOE epsilon4 carriers than in APOE epsilon3 carriers only in the group with AD. Conclusion: APOE epsilon4 did not increase the risk for AD in this Mexican Mestizo elderly urban population sample, although the presence of this allele seems to modify its clinical expression