Table 1 Study characteristics

Cummings (1999) [45]

Adequacy of discharge plans & re-hospitalisation among hospitalised dementia patients

Prospective cohort, hospital, 1996–1997, USA

To measure the adequacy of overall discharge plans developed for older adults with dementia

Hospital medical records

131 older inpatients with moderate-severe dementia.

Social workers (SW) developed discharge plan Discharge plans rated by primary care providers 1 month post discharge

Measure: 30-day hospital readmission. Readmission rate: 18.3%

35% discharge plans rated less than adequate or very inadequate.

Logistic regression of factors predicting readmission were SW adequacy ratings (p < 0.01), patient gender (p < 0.01), caregiver support (p < 0.05).

Rudolph et al. (2010) [49]

Hospitalisation in community-dwelling persons with Alzheimer’s Disease (AD): Frequency & causes

Longitudinal study, hospital, 1991–2006, USA

To clinically identify patients with AD at high risk for hospitalisation based on baseline risk factors

Hospital medical records

827 patients with AD aged 65 + years

Measure:

First hospitalisation in study period.

Rate: 66% hospitalised at least once, 47% hospitalised two or three times during study period

Leading reasons for hospitalisation include: syncope/falls (26%), ischaemic heart disease (17%), gastrointestinal disease (9%), pneumonia (6%) and delirium (5%).

Significant independent risk factors for hospitalisation were higher comorbidity (HR 1.87), previous acute hospitalisation (HR 1.65), older age (HR 1.51), male sex (HR 1.27) shorter duration of dementia symptoms (HR 1.26).

Callahan et al. (2012) [50]

Transitions in care for older adults with and without dementia

Prospective cohort, transitional care, 2001–2008, USA

To gain a complex understanding of the frequency and type of transitions in care of older adults with and without dementia

Medical records

4,197 primary care older adult patients (1,523 with dementia)

Measure: 30-day rehospitalisation after index admission.

Rate: 23% for older adults with dementia. 28% for older adults with dementia with 30-day or shorter rehospitalisation.

Of the 30-day re-hospitalisations, 17% were discharges from index hospitalisations to home with healthcare services, 38% were discharges to home without home healthcare services, and 45% were discharges to a nursing facility.

Daiello et al. (2014) [53]

Association of dementia with early re-hospitalisation among Medicare beneficiaries

Retrospective cohort, hospital, Jan-Dec 2009, USA

To investigate the risk of rehospitalisation among Medicare beneficiaries with and without dementia.

Medicare insurance claims records

16,244 Medicare beneficiaries

Measure: 30-day hospital readmission in a 12-month period Rate: 17.8% vs. 14.5% (dementia vs. no dementia)

Dementia diagnosis was a predictor of 30-day readmission (unadjusted OR 1.28). Association persisted after adjustment for age, gender, number of long-term conditions, length of first hospital stay, number of admissions in previous year (OR 1.18).

Prescriptions for antipsychotic medication that were recorded at least twice in the study period occurred more frequently in PLWD with 30-day hospital readmissions (12.7% readmission vs. 9.2% no readmission p < 0.001).

Chang et al. (2015) [44]

The impact admission etiology on recurrent or frequent admission

Prospective cohort, hospital, 2007–2014, Taiwan

To explore the roles of dementia subtypes, cerebrovascular risk factors, systemic diseases and the etiology for admission in predicting recurrent and prolonged hospitalisation

Hospital medical records

203 patients aged over 65 years with Alzheimer’s disease, vascular dementia or Parkinsonism-related dementia diagnosis.

Clinical Dementia Rating score of 1–2 (mild-moderate)

Length of admission ≧ 14 days per hospitalisation and admission frequency ≧ 4 times in 4 years

Readmission rate: 8.9%

Coronary artery disease associated with frequent admission (p = 0.023). For admission etiology, pneumonia, UTI and falls-related fracture highly associated with frequent admission (all < 0.0001).

Admission etiologies have higher clinical weighting than dementia subtype and co-existing medical conditions, to predict recurrent admission and prolonged hospital stay.

Tropea et al. (2016) [52]

Poorer outcomes and greater healthcare costs for hospitalised older people with dementia and delirium

Retrospective cohort, hospital, 2006–2012, Australia

To compare healthcare utilisation outcomes among older hospitalised patients with and without cognitive impairment (CI), and to compare the costs associated with these outcomes.

Hospital medical records

50,261 Hospital patients with cognitive impairment (defined by ICD-10 diagnoses codes for dementia and delirium)

Measure: 28-day readmission rate

Rate: Initially no significant difference of 2, 7 or 28 day readmissions between CI and non-CI patients. However, when discharged back to usual place of residence/home, the odds of 2, 7 & 28 day readmission increased for CI patients (OR 1.32, 1.22, 1.27)

The total cost of index admissions and 28-day readmissions involving CI patients was 47% higher than the cost of episodes involving non-CI patients.

Increased rate of readmission for CI patients when discharged back home may indicate inappropriate discharge and further bed-based/transitional care/rehabilitation was required, or inadequate support services in place for successful transition back home.

Gilmore-Bykovskyi et al. (2017) [55]

Transitions From Hospitals to Skilled Nursing Facilities (SNF) for Persons With Dementia: A Challenging Convergence of Patient and System-Level Needs

Qualitative interviews, nursing home, 2015, USA

To examine SNF nurses’ perspectives regarding experiences and needs of people with dementia during hospital to SNF transitions & to identify factors related to the quality of these transitions

SNF nurses

51 SNF nurses

N/A

Under-communication was perceived as resulting in inappropriate placement, risk for rehospitalisation & patient harm.

Hospital time pressures to discharge quickly, differences in the emphasis of medical & social/behavioural needs between hospital & SNF settings, differing views on transparency about behavioural symptoms & what defines a successful transition between hospital and SNFs, were areas of conflict described from nurses between SNF and hospitals.

Gustafsson et al. (2017) [56]

Pharmacist participation in hospital ward teams and hospital readmission rates among PWD

RCT, hospital, 2012–2014, Sweden

To assess whether comprehensive medication reviews conducted by clinical pharmacists could reduce the rate of drug-related admissions among people with dementia

Medical records

460 patients aged 65 + with dementia or cognitive impairment

Measure: 30 and 180-day readmission

30-day readmission rate: 5% intervention group, 11% control group (p = 0.03)

180-day readmission rate: 11% intervention, 20% control (p = 0.02) [sub-grp analysis of patients without heart failure]

Pharmacist participation did not significantly reduce 180-day readmissions in patients with heart failure (HF) (maybe as HF is a severe condition and can have many exacerbations). Reasons for reduced 180-day and 30-day readmissions in patients without HF may be due to close collaboration between pharmacist and ward medical team, as the pharmacist was already working on the ward and known to the team before the study.

Lin et al. (2017) [51]

Hospitalisations for ambulatory care sensitive conditions and unplanned readmissions among Medicare beneficiaries with Alzheimer’s disease

Retrospective cohort, hospital, 2013, USA

To examine the frequency and costs of potentially avoidable hospitalisations and unplanned 30-day readmissions in the entire Medicare fee-for-service population with dementia

Hospital insurance records

2,749,172 adults aged 65 + years with dementia

Measure: 30-day hospital readmission.

Rate: 18% Of this amount, 73% had one all-cause 30-day admission, whereas 18% were readmitted twice and 9% were readmitted three or more times

Readmissions varied by diagnosis of index admission: 22% for heart failure, 21% for COPD, 19% for acute myocardial infarction, 18% for coronary artery bypass graft, 15% for pneumonia, 12% stroke, 9% hip/knee replacement.

In total, 410,000 dementia patients had 567,000 ambulatory care sensitive condition (ACSC) hospitalisations or unplanned readmissions in 2013, costing Medicare $374 million/year. Such hospitalisations may be indicative of access barriers, problems in continuity of care, inefficient resource use, and poor patient outcomes.

Sakata et al. (2018) [18]

Dementia and risk of 30-day readmissions in older adults after discharge from acute care hospitals

Retrospective cohort, hospital, 2014–2015, Japan

To assess the association between dementia and risk of hospital readmission, accounting for primary diagnosis as a possible effect modifier

Diagnosis procedure combination database

1,834,378 Adults over 65 with and without dementia with 2 or more hospital admissions within study period

Measure: 30-day unplanned hospital readmission.

Readmission rate: 8.3% (dementia) vs. 4.1% (control)

Significant associations between dementia and hospital readmission among 17/30 most common diagnostic categories including pneumonia and heart failure. Hip fracture was associated with greater readmission risk for people with dementia (11.5% vs. 7.9%).

Greater readmission risk could be due to limited ability to follow post-discharge directions which may lead to poor health outcomes and readmission.

Van de Vorst et al. (2018) [19]

Increased mortality and hospital readmission risk in patients with dementia & a history of cardiovascular disease (CVD)

Prospective cohort, day clinic and hospital, 2000–2010, Netherlands

To evaluate the impact of CVD on mortality & hospital readmission risk in hospitalised dementia patients

Hospital database records

59,194 patients with dementia. 36.9% with CVD history

Measure: all-cause 1 year readmission

Readmission rate: Day clinic patients with CVD = 49.7%, no CVD = 40.6% Hospital patients with CVD = 37.3%, no CVD = 28.1%

The presence of CVD increases the risk of hospital readmission in both day clinic and hospitalised patients with dementia.

Day clinic HR = 1.26

Hospital HR = 1.34

Knox et al. (2020) [47]

Function & caregiver support associated with readmissions during home health for individuals with dementia

Retrospective cohort, home care, 2013–2015, USA

To determine the association between mobility, self-care, cognition and caregiver support, and 30-day potentially preventable readmissions (PPR) for people with dementia

Medical records

118,171 individuals with dementia

Measure: 30-day potentially preventable readmission.

30-day PPR rate: 7.6%

People with dementia who were most dependent on mobility (OR 1.59), and self-care (OR 1.73) had higher odds for PPR.

The largest difference in 30-day PPR rates were according to the number of acute hospital stays in the prior year with 4 + stays having a 30-day PPR rate of 25.2% compared to 2.5% with patients with no other acute stays in the previous year.

Godard-Sebillotte et al. (2021) [17]

Primary care continuity & potentially avoidable hospitalisations in people with dementia

Retrospective cohort, primary care, 2014–2015, Canada

To estimate the association between high primary care continuity & potentially avoidable hospitalisation in community-dwelling people with dementia.

High primary care defined as having had every primary a visit with the same physician.

Healthcare data

22,060 Community-dwelling people with dementia aged 65+, not awaiting admission to a long-term care facility

Measure: 30-day hospital readmission

Readmission rate: rr = 0.81 (p < 0.001)

Reasons for reduced hospitalisation: Primary care may improve management of chronic conditions & detection & treatment of acute exacerbations; increase the ability to identify & communicate acute symptoms between people with dementia and physicians.

Graversen et al. (2021) [16]

Dementia and the risk of short-term readmission and mortality after a pneumonia admission

Retrospective cohort, hospital, 2000–2016, Denmark

To investigate 30-day mortality and readmission after hospital discharge for pneumonia in people with vs. without dementia

Hospital medical records

25,948 people with dementia aged 65–99 years

Measure: 30-day hospital readmission

Readmission rate: 21.9% in people with dementia (14.9% in those without dementia)

In people with dementia, the highest readmission risks were found in the first week post-discharge. Could reflect in-hospital factors i.e. illness burden inpatient care process factors, poor discharge planning.

Knox et al. (2021) [46]

Mobility and self-care are associated with discharge to community after Home Health for people with dementia

Retrospective cohort, home care, 2016–2017, USA

To determine the relationship between dementia, mobility, self-care tasks, caregiver support and medication management with successful discharge to community (DTC) after home health.

Medical records

790,439 Medicare beneficiaries (18% with dementia)

Measure: Successful DTC (discharged to community without experiencing readmission or death within 30 days of discharge).

Successful DTC rate: Dementia = 71%. No dementia = 81%.

People with dementia had significantly lower odds of successful DTC compared to people without dementia (rr = 0.947).

The primary reason for unsuccessful DTC in ADRD was readmission during home health care, followed by unplanned readmission after discharge from home health care and mortality.

Living alone and inadequate care was shown to increase the likelihood of readmissions i.e. those with dementia who were dependent on caregiver assistance and unable to manage their own medication had a lower risk of successful DTC.

Tannenbaum et al. (2022) [54]

Hospital practices and clinical outcomes associated with behavioural symptoms in persons with dementia

Retrospective cohort, hospital, January-December 2019, USA

To identify clinical practices and outcomes associated with behavioural symptoms in hospitalised PLWD.

Electronic hospital records

8,876 hospitalised people with dementia aged 65 years and over

Measure: 30-day hospital readmission

Readmission rate: 14% (n = 1305)

40.6% (n = 3606) of hospitalised PLWD had behavioural symptoms.

PLWD with behavioural symptoms were more likely to be male (40.3% vs. 36.9%, p = 0.001), and White (62.7% vs. 58.3%, p < 0.001), and more likely to come from a care facility (26.6% vs. 23.7%, p < 0.05).

Gilmore-Bykovskyi et al. (2023) [57]

Disparities in 30-day readmission rates among Medicare enrolees with dementia

Retrospective cohort, hospital, 2014, USA

To examine the association between race and 30-day readmissions in Medicare beneficiaries of Black and non-Hispanic White people with dementia

Hospital insurance records

1,523,142 hospital stays. 86% non-Hispanic White, 14% Black

Measure: all-cause 30-day readmission

Readmission rate among Black beneficiaries:

37% unadjusted, 16% adjusted

Black beneficiaries more likely to live in disadvantaged, urban neighbourhoods, and had twice as much disability compared to non-Hispanic Whites.

50% of observed risk of readmissions in Black people is determined by unmeasured exposures of racial differences.