The nursing home effect: a case study of residents with potential dementia and emergency department visits.

Objectives: The burden of potential dementia cases without formal diagnosis on the health care system is almost unknown. This study examined the impact of potential dementia without formal diagnosis on the rate of visits to hospital emergency department (ED) of nursing home (NH) residents.

Design: Cross-sectional study.

Setting: NHs (175) located in France.

Participants: A total of 5684 subjects who were living in the NH for at least 1 year.

Measurements: Information on NHs' characteristics and on NH residents' health was recorded by NH staff. Participants were divided in 3 groups according to their dementia status: diagnosed dementia, potential dementia without formal diagnosis, and nondementia. The outcome measure was a binary variable: ED visits in the last 12 months (yes vs no). A mixed-effects logistic regression was performed on ED visits accounting for the random effects of living in a particular NH.

Results: From the 5684 participants, 1036 had been seen in the ED. Adjusted odds ratio (AOR) showed that having a potential dementia without formal diagnosis, compared with a diagnosed dementia, was associated with an increased probability of ED visits (AOR = 1.25, 95% confidence interval: 0.99-1.59, P = .061); however, when a random NH effect was entered into the model, the association between potential dementia without formal diagnosis and ED visits disappeared (AOR = 1.22, 95% confidence interval: 0.95-1.57, P = .11).

Conclusion: The association of potential dementia without formal diagnosis with ED visits varies across NHs. This intra-NH aspect (eg, organization and care habits) should be taken into account when examining the rates of hospitalization and possibly the use of health care services in general among NH residents.