nalizing disorder that could potentially hamper
effective communication with health care profes-
sionals, delaying a potential diagnosis and conse-
quent treatment. Depressive symptoms in older
adults could aggravate chronic diseases and dis-
This could unfavourably inuence older
people’s ability to look after themselves, leading
to poorer self-perceived health, an increase in
unexplained physical symptoms and, conse-
quently, a rise in medical admissions. Further-
more, there is an association between the number
of physical conditions and depression, and a
dose–response relation has been described.
In the current study, we have found that, even
after adjustment for a robust measure of comor-
bidity (Charlson index), depression was a strong
independent risk factor for hospital admission,
longer hospital stays and worse hospital out-
comes. This suggests that the association between
depression and comorbidity, disability and hospi-
tal admission is complex and cannot be attributed
solely to age, prevalent clinical morbidity, social
support, education or smoking. However, even
after adjustment for comorbidities, it is difcult
to know to what extent depression may be a man-
ifestation of early stages of diseases. We cannot
therefore exclude the possibility that the ndings
may partially reect depression as an epiphenom-
enon for other diseases.
We found a dose–response relation between
depression severity and hospital admission,
which suggests that reducing the symptoms may
potentially improve hospital outcomes. However,
subthreshold symptoms should not be underesti-
mated, because they still have an impact on hos-
pital admission and associated outcomes.
Our study population was limited to men aged
69 years and older. We do not know whether our
ndings are generalizable to younger adults,
women and people living outside Australia,
although there is no obvious reason that this
would not be the case, particularly in other
developed countries. Although the GDS-15 has
been proven to be a valid instrument for screen-
ing for major depressive disorder, it does not
have the potential to differentiate between symp-
toms of major depressive disorder and depressive
symptoms caused by other psychiatric diagnoses
(e.g., dementia, psychosis), which could affect
the interpretation of our results. We measured
depressive symptoms only at baseline, and this
exposure could have changed during the follow-
up period. Hence, we were unable to determine
whether change in depressive status could affect
Finally, the Charlson weighted index was
originally created to estimate death and may not
take into account all of the diagnoses that may
increase hospital admission. Future research
could involve a more comprehensive index to
account for comorbidities.
Our study emphasizes the independent associa-
tion between the presence of depressive symp-
toms in older men living in the community and
hospital admissions, highlighting a possible tar-
get to identify men with potentially preventable
admissions. Larger studies may be able to inves-
tigate effect modication, to determine more
clearly what factors, if any, mediate the relation
between depression and hospital outcomes. It is
not clear whether reducing depressive symptoms
would result in fewer hospital admissions, and
further research is required to clarify this issue.
Our data extend previous ndings on the associa-
tion between depression and hospital admission,
with focus on the general population and admis-
sion frequency, length of stay and outcomes.
1. Rogal SS, Landsittel D, Surman O, et al. Pretransplant depres-
sion, antidepressant use, and outcomes of orthotopic liver trans-
plantation. Liver Transpl 2011;17:251-60.
2. Sheeran T, Byers AL, Bruce ML. Depression and increased
short-term hospitalization risk among geriatric patients receiving
home health care services. Psychiatr Serv 2010;61:78-80.
3. Volz A, Schmid JP, Zwahlen M, et al. Predictors of readmission
and health related quality of life in patients with chronic heart
failure: a comparison of different psychosocial aspects. J Behav
4. Turner A, Phillips L, Hambridge JA, et al. Clinical outcomes
associated with depression, anxiety and social support among
cardiac rehabilitation attendees. Aust N Z J Psychiatry 2010; 44:
5. Blanchette CM, Simoni-Wastila L, Shaya F, et al. Health care
use in depressed, elderly, cardiac patients and the effect of anti-
depressant use. Am J Health Syst Pharm 2009;66:366-72.
6. Kronish IM, Rieckmann N, Schwartz JE, et al. Is depression after
an acute coronary syndrome simply a marker of known prognos-
tic factors for mortality? Psychosom Med 2009;71:697-703.
7. Kurdyak PA, Gnam WH, Goering P, et al. The relationship
between depressive symptoms, health service consumption, and
prognosis after acute myocardial infarction: a prospective cohort
study. BMC Health Serv Res 2008;8:200.
8. Song EK, Lennie TA, Moser DK. Depressive symptoms
increase risk of rehospitalisation in heart failure patients with
preserved systolic function. J Clin Nurs 2009;18:1871-7.
9. Norman PE, Flicker L, Almeida OP, et al. Cohort prole: the
Health In Men Study (HIMS). Int J Epidemiol 2009;38:48-52.
10. Holman CD, Bass AJ, Rouse IL, et al. Population-based linkage
of health records in Western Australia: development of a health
services research linked database. Aust N Z J Public Health
11. Almeida OP, Almeida SA. Short versions of the geriatric depres-
sion scale: a study of their validity for the diagnosis of a major
depressive episode according to ICD-10 and DSM-IV. Int J
Geriatr Psychiatry 1999;14:858-65.
12. Koenig HG, Westlund RE, George LK, et al. Abbreviating the
Duke Social Support Index for use in chronically ill elderly indi-
viduals. Psychosomatics 1993;34:61-9.
13. Charlson ME, Pompei P, Ales KL, et al. A new method of clas-
sifying prognostic comorbidity in longitudinal studies: develop-
ment and validation. J Chronic Dis 1987;40:373-83.
14. Quan H, Sundararajan V, Halfon P, et al. Coding algorithms for
dening comorbidities in ICD-9-CM and ICD-10 administrative
data. Med Care 2005;43:1130-9.
15. Prina AM, Deeg DJ, Brayne C, et al. The association between
122 CMAJ, February 5, 2013, 185(2)