Abstract
Objectives
There is lack of data on the frequency and the causes of hospitalization in mild to moderate Alzheimer's disease (AD) patients. The aims of the present study were to evaluate the frequency and the causes of hospitalization in a large prospective cohort of mild to moderate patients with AD.
Design
Six hundred and eighty-six AD patients from the French Network on AD (REAL.FR) were followed up and assessed every 6 months for 2 years. During follow-up, all events occurring between two visits, in particular hospital admissions or nursing home placements were carefully recorded.
Results
Annual incidences for hospitalizations were 26.2% (95% CI, 22.5 to 29.7). After two years, 202 subjects were hospitalized for 296 hospitalizations. 139 subjects were hospitalized once, 40 twice, 13 three times, 4 four times and 2 five times during the two-year follow-up. The duration of hospitalization was 14.3 +/− 23.5 days. For repeated hospitalizations, the time interval between the first and the second hospitalization was 176.4 days (SD 150.2) and the cause of multiple hospitalizations was most different. Fractures and falls not causing fracture were the main reasons for hospital admission (20.9%), followed by cardiovascular disorders (14.5%) and by behavioural disorders (11.0%). Admission due to associated diseases or life events was the main reason for hospitalization (75.7%).
Conclusions
Hospitalization is a frequent event for AD patients even at mild to moderate stage of the disease. In this cohort, the major causes for hospital admission were due to associated diseases or life events and not due to the direct consequences of the disease itself.
Key words: Alzheimer's disease, hospitalization, REAL.FR, diagnosis
Introduction
Alzheimer’s disease is associated with a number of complications such as weight loss, enhanced risk for falls, infections, behavioural disorders, social grounds (1). During the course of the disease, many patients need to be hospitalized either due to the direct consequences of the disease itself, or due to associated diseases or life events.
A recent review of the literature by Maslow (2) revealed that in 2000, an estimated 3.2 million hospitalizations involved elderly persons with AD or a related dementia.
However, the frequency and the causes of hospitalization in these patients have not been well documented. The aims of the present study were to evaluate the frequency and the causes of hospitalization in a large prospective cohort of patients with AD.
Materials and Methods
The REAL.FR study is a prospective multicentric study in which 686 patients with AD according to the National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer’s Disease and Related Disorders Association (NINCDS-ADRDA) (3) and Diagnostic and Statistical Manual of Mental Disorders (4th edition) (DSM-IV) (4) criteria were recruited throughout France between 2000 and 2002. The methodology of the study has been described in detail elsewhere (5). Patients with mild to moderate disease, Mini-Mental State Examination (MMSE) score between 10 and 26 (6), living in the community, and having a clearly identified informal caregiver were included. At inclusion, the patients underwent a full medical examination (including computed tomography scan and thyroid tests). We excluded from the study patients with severe AD, those who were institutionalized at baseline, and those with a concomitant disorder that could affect the short-term prognosis.
Follow-up included prospective data collection at 6-month visits for 2 years in 16 participating centres (gerontology, neurology, or psychiatry). At each visit a standardized case report form was completed for each patient by a trained, multidisciplinary medical team.
Hospitalization was defined as a hospital inpatient stay of at least 24h. All types of hospital admissions were considered (general medical ward, psychiatric ward or specialised unit). Hospital admissions due to associated diseases or life events were defined as hospitalization for cardiovascular disorders, infectious disease, surgery, cancer, etc… Hospital admissions due to the direct consequences of the disease itself were defined as hospitalization for behavioural disorders or discharge.
During follow-up, all events occurring between two visits, in particular hospital admissions or nursing home placements were carefully recorded. Dropouts were also analyzed, and we distinguished deaths, entry to an institution where follow-up was not possible, withdrawal of consent, medical problems of patient or caregiver, or loss to follow up. To minimize the impact of attrition on our results, we set up a procedure that allowed us to collect data concerning vital status and institutionalizations of the patients who had prematurely stopped the follow-up by establishing a contact with the caregiver or general practitioner.
We first described baseline parameters of AD patients from the REAL.FR cohort; for each of the modalities of the qualitative variables, the number and frequency are given; continuous variables are expressed as means and standard deviations.
Results
Baseline social, demographic and clinical data of the 686 AD patients included in the REAL.FR study are summarized in Table 1. According to the inclusion criteria, all patients presented a mild to moderate stage of AD and lived at home. Table 2 shows the frequency of hospitalizations and repeat hospitalizations. Annual incidences for hospitalizations were 26.1% (95% CI, 22.5 to 29.7). After two years, 202 subjects were hospitalized for 296 hospitalizations. 139 subjects were hospitalized once, 40 twice, 13 three time, 4 four time and 2 five time during the two years of follow-up. Principal characteristics of hospitalizations are described in table 2. The duration of hospitalization was 14.3 +/- 23.5 days. For repeat hospitalization, the time between the first and the second hospitalization were 176.4 days (SD 150.2) and the cause of the rehospitalization was mostly different. The principal causes for hospitalization are listed in the table 3. Fractures and falls not causing fracture were the main reason for hospital admission (20.9%), followed by cardiovascular disorders (14.5%) and by behavioural disorders (11.0%). The major reasons for hospital admission were due to associated diseases or life events and not due to the direct consequences of the disease itself. Admission due to associated diseases or life events was the main reason for hospitalization (75.7%). The direct consequences of the disease itself like behavioural disorders or discharge were less frequent.
Table 1.
Baseline characteristics of the AD patients included in REAL.FR study
| Patients Included n=686 | |
|---|---|
| Age (y, mean +/- SD) | 77.8 +/- 6.8 |
| Sex (M/F, n, %) | 198/488 (29.8/71.1) |
| Duration of AD (y) | 1.1 +/- 1.2 |
| Living arrangement (n, %) | |
| With relatives | 503 (73.3) |
| Alone | 183 (26.7) |
| Specific AD treatment (n, %) | 611 (89.0) |
| MMSE score (/30, mean +/- SD) | 20.01 +/- 4.2 |
| ADAS-cog score (/70, mean +/- SD) | 17.8 +/- 8.2 |
| ADL score (/6, mean +/- SD) | 5.4 +/- 0.9 |
| NPI score (/144, mean +/- SD) | 15.3 +/- 15.3 |
| MNA score (/30, mean +/- SD) | 23.9 +/- 3.1 |
| CDR-SB (/18, mean +/- SD) | 6.4 +/- 3.3 |
Abbreviation: SD, standard deviation; AD, Alzheimer Disease; MMSE, Mini Mental State Examination; ADAS-cog, Alzheimer’s disease Assessment Scale for cognitive evaluation; ADL, Activities of Daily Living; NPI, Neuropsychiatric Inventory; MNA, Mini Nutritional Assessment; CDR-SB, Clinical Dementia Rating - sum of boxes
Table 2.
Principal characteristics of the hospitalizations in REAL.FR study at 2 years
| Number of hospitalizations (n) | 296 |
| Number of hospitalized subjects (n,%) | 202 (29.4) |
| Emergency hospital admission (n,%) | 115 (41.4) |
| Admissions due to associated diseases or life events | (n, %)215 (75.7) |
| Duration of hospitalization (day, SD) | 14.3 +/- 23.5 |
| Number of hospitalization | |
| Once (n, %) | 139 (68.8) |
| Twice (n, %) | 40 (19.8) |
| Three time (n, %) | 17 (8.4) |
| Four time (n, %) | 4 (2.0) |
| Five hospitalizations (n, %) | 2 (1.0) |
| Time between two hospitalizations (day, SD) | 176.4 +/- 150.2 |
| Same cause for rehospitalisation (n, %) | 14 (17.7) |
Abbreviation: SD, standard deviation
Table 3.
Principal causes for hospitalizations
| Hospitalizations | |
|---|---|
| N=296 hospitalizations | |
| Cardiovascular disorders (n, %) | 42 (14.5) |
| Fractures (n, %) | 36 (12.7) |
| Behavioural disorders (n, %) | 31 (11.0) |
| Surgery (n, %) | 26 (9.2) |
| Falls not causing fractures (n, %) | 23 (8.1) |
| Neurologic Disorders (n, %) | 19 (6.7) |
| Infectious disease (n, %) | 11 (3.9) |
| Cancer (n, %) | 10 (3.5) |
| Discharge (breakdown in caregiver network) (n, %) | 8 (2.8) |
| Other causes: non-specific disorder, disease of blood, digestive system, … (n, %) | 90 (30.4) |
Discussion
Hospitalizations in AD patients appear to be frequent. In the study by Albert et al., advanced AD was significant risk factor for hospitalization and subjects with mild or moderate AD did not show a significantly elevated risk (7). In this study 17.5% of AD patients were hospitalized in 21 months of follow-up. In our study, during the 2 years of follow up 202 patients were hospitalized (29.4%) for 296 hospitalizations. The annual incidences for hospitalizations were 26.1% (95% CI, 22.5 to 29.7) of patients with mild to moderate AD. In comparison, in the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) program, Fillenbaum et al. reported 289 hospitalizations for 477 AD patients with 4.2 years median of follow up (8). In this study, hospitalized AD patients had an average of 10 days length of stay / hospitalizations. In our study, the duration of hospitalization was 14.3 +/- 23.5 days. We could not compare the two studies because the stage of the disease in the CERAD program was more severe. In our study, almost one fourth of the participants at the survey were hospitalized each year. These results showed that in spate of the maintenance of a good global status, rates for hospitalization was high probably because the major causes for hospitalization were not due to the direct consequences of the disease itself. Moreover, it was difficult to classify causes of hospitalization between associated diseases or the disease itself. Some causes like falls, fracture can be due to the consequence of the disease but not due directly to Alzheimer’s disease. This classification can be a subject of discussion.
Falls not causing fracture and fracture were the mean reasons for hospital admission in our study population. The other reasons for hospital admission are the result of the associated diseases or life events found in all elderly people. The second most frequent cause (14.5%) was cardiovascular disorders. The third most frequent cause of admission was related to behavioural problems (11.0%). In other studies behavioural problems were the leading cause of hospitalization (9, 10). The mild to moderate stages of our population could explain these differences. The mean of the MMSE score was 20.0 +/- 4.2 in the REAL.FR study, which is very high in comparison to other studies (1, 9).
Discharge (breakdown in caregiver network) reasons were expressed in only 2.8% of cases. These results were consistent with a study focus on emergency hospital admissions of patients with AD (1). Other study has reported more discharge, but over again the population was more severe than in our study (9).
Thanks to inclusion criteria of the REAL.FR study (mild to moderate AD living at home) results obtained in this large cohort are more representative of the current general population with AD than those usually reported and complete the data on hospitalizations in AD with more severe patients.
The results of this study demonstrate that hospitalization is a frequent event for AD patients even at mild to moderate stage of the disease. The major causes for hospital admission were due to associated diseases or life events and not due to the direct consequences of the disease itself in this cohort. Some of these events like falls can potentially be prevented by early, targeted intervention (11,12) and systematic, comprehensive geriatric assessment might decrease the rates of hospitalizations or readmissions, and the costs of providing care (13).
Prevention of life events or optimal treatment of associated diseases in AD seem to be also a challenge to decrease the rates of hospitalizations or readmissions, and the costs of providing care.
Acknowledgements
This work was supported by a grant from the Clinical Research Program Hospital from the French Ministry of Health (PHRC No 98-47N, PHRC No 0101001). REAL-FR group: principal investigator: Prof B. Vellas (Toulouse); associate investigators: Pr M. Rainfray, Dr S. Richard-Harston (Bordeaux); Pr P. Couturier, Pr A. Franco (Grenoble); Pr F. Pasquier, Dr M. A. Mackowiak-Cordoliani (Lille); Dr B. Frigard, Dr H. Idiri, Dr K. Gallouj (Wasquehal); Dr B. Michel (Marseille); Pr Cl. Jeandel (Montpellier); Pr J. Touchon, Dr F. Portet, Dr S. Lerouge (Montpellier); Pr Ph. Robert, Dr P. Brocker, C. Bertogliati (Nice); Pr B. Forette, Pr L. Teillet, Dr L. Lechowski (Paris); Pr J. Belmin, D. S. Pariel-Madjlessi (Paris); Pr M. Verny, Dr M. A. Artaz (Paris); Pr F. Forette, Pr A. S. Rigaud, Dr F. Latour (Paris); Pr P. Jouanny, Dr S. Belliard, Dr O. Michel (Rennes); Dr C. Girtanner, Dr Thomas- Anterion (Saint Etienne); study coordinators: F. Cortes, S. Gillette-Guyonnet, Prof. F. Nourhashemi, Dr P.J. Ousset (Toulouse); epidemiologist: Pr S. Andrieu; data processing: C. Cantet.
References
- 1.Nourhashemi F., Andrieu S., Sastres N., Ducasse J.L., Lauque D., Sinclair A.J., Albarede J.L., Vellas B. Descriptive analysis of emergency hospital admissions of patients with Alzheimer disease. Alzheimer Disease and Associated Disorders. 2001;1(15):21–25. doi: 10.1097/00002093-200101000-00003. 10.1097/00002093-200101000-00003 [DOI] [PubMed] [Google Scholar]
- 2.Maslow K. In: Improving hospital care for persons with dementia. Silverstein N.M., Maslow K., editors. Springer; New York: 2006. How many people with dementia are hospitalized? pp. 3–21. [Google Scholar]
- 3.McKhann G., Drachman D., Folstein M., Katzman R., Price D., Stadlan E.M. Clinical diagnosis of Alzheimer’s disease: report of the NINCDS-ADRDA work group under the auspices of Department of Health and Human Services Task Force on Alzheimer’s Disease. Neurology. 1984;34:939–944. doi: 10.1212/wnl.34.7.939. PubMed PMID: 6610841. [DOI] [PubMed] [Google Scholar]
- 4.American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th ed. APA; Washington, DC: 1994. [Google Scholar]
- 5.Gillette-Guyonnet S., Nourhashemi F., Andrieu S., Cantet C., Micas M., Ousset P.J., et al. REAL.FR group: the REAL.FR research program on Alzheimer’s disease and its management: methods and preliminary results. J Nutr Health Aging. 2003;7:91–96. PubMed PMID: 12679828. [PubMed] [Google Scholar]
- 6.Folstein M.F., Folstein S.E., McHugh P.R. Mini-Mental State: a practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res. 1975;12:189–198. doi: 10.1016/0022-3956(75)90026-6. 10.1016/0022-3956(75)90026-6 PubMed PMID: 1202204. [DOI] [PubMed] [Google Scholar]
- 7.Albert S.M., Costa R., Merchant C., Small S., Jenders R.A., Stern Y. Hospitalization and Alzheimer’s disease: results from a community-based study. J Gerontol A Biol Sci Med Sci. 1999;54(5):M267–M271. doi: 10.1093/gerona/54.5.m267. PubMed PMID: 10362011. [DOI] [PubMed] [Google Scholar]
- 8.Fillenbaum G., Heyman A., Peterson B., Pieper C., Weiman A.L. Frequency and duration of hospitalization of patients with AD based on Medicare data: CERAD XX. Neurology. 2000;54:740–743. doi: 10.1212/wnl.54.3.740. PubMed PMID: 10680815. [DOI] [PubMed] [Google Scholar]
- 9.Andrieu S., Reynish E., Nourhashemi F., Shakespeare A., Moulias S., Ousset P.J., Sagnier P., Richard A., Albarede J.L., Vellas B. Predictive factors of acute hospitalization in 134 patients with Alzheimer’s disease: a one year prospective study. Int J Geriatr Psychiatry. 2002;17:422–426. doi: 10.1002/gps.624. 10.1002/gps.624 PubMed PMID: 11994930. [DOI] [PubMed] [Google Scholar]
- 10.Neville P., Boyle A., Baillon S. A descriptive survey of acute bed usage for dementia care in old age psychiatry. Int J Geriatr Psychiatry. 1999;14:348–354. doi: 10.1002/(sici)1099-1166(199905)14:5<348::aid-gps915>3.0.co;2-b. 10.1002/(SICI)1099-1166(199905)14:5<348::AID-GPS915>3.0.CO;2-B PubMed PMID: 10389037. [DOI] [PubMed] [Google Scholar]
- 11.Tinetti M.E., Baker D.I., McAvay G., Claus E.B., Garret P., Gottschalk M., Koch M.L., Trainor K., Horwitz R.I. A multifactorial intervention to reduce the risk of falling among elderly people living in the community. N Engl J Med. 1994;331(13):821–827. doi: 10.1056/NEJM199409293311301. 10.1056/NEJM199409293311301 PubMed PMID: 8078528. [DOI] [PubMed] [Google Scholar]
- 12.Shaw F.E., Kenny R.A. Can falls in patients with dementia be prevented? Age Ageing. 1998;27:7–9. doi: 10.1093/ageing/27.1.7. 10.1093/ageing/27.1.7 PubMed PMID: 9504359. [DOI] [PubMed] [Google Scholar]
- 13.Naylor M.D., Brooten D., Campbell R., Jacobsen B.S., Mezey M.D., Pauly M.V., Schwartz J.S. Comprehensive discharge planning and home follow-up of hospitalized elders: a randomized clinical trial. JAMA. 1999;281(7):613–620. doi: 10.1001/jama.281.7.613. 10.1001/jama.281.7.613 PubMed PMID: 10029122. [DOI] [PubMed] [Google Scholar]