Available online at www.sciencedirect.com

y 30 (2008) 245–251

General Hospital Psychiatr

Recognition of depression in older medical inpatients discharged toambulatory care settings: a longitudinal study

Jane McCusker, M.D., Dr.P.H.a,b,⁎, Martin Cole, M.D., F.R.C.P.(C)b,c,Eric Latimer, Ph.D.b,d, Maida Sewitch, Ph.D.a,b, Antonio Ciampi, Ph.D.a,b,

Monica Cepoiu, M.D., M.Sc.a, Eric Belzile, M.Sc.aaDepartment of Clinical Epidemiology and Community Studies, St. Mary's Hospital, Montreal, Quebec, Canada H3T 1M5

bMcGill University, Montreal, Quebec, Canada H3A 2T5cSt. Mary's Hospital, Montreal, Quebec, Canada H3T 1M5dDouglas Hospital, Montreal, Quebec, Canada H3T 1M5

Received 28 November 2007; accepted 23 January 2008

Abstract

Objective: This study aimed to examine the recognition of depression in older medical inpatients by nonpsychiatric physicians over a2-year period.Methods: A cohort of medical inpatients aged 65 and above was recruited at two university-affiliated hospitals, with oversampling ofdepressed patients. Participants were assessed with research diagnoses of major or minor depression (DSM-IV) at admission and at 3, 6 and12 months. Indicators of recognition during the 12 months before and the 12 months after admission, derived from administrative databases,included the following: depression diagnosis, antidepressant prescription and psychiatric referral. Multiple logistic regression analyses wereused to identify factors associated with recognition.Results: Among 185 patients with at least one research diagnosis of depression during the study, recognition rates ranged up to 56% duringthe 12 months before admission among patients with major depression lasting at least 6 months and up to 61% during the 12 months afteradmission among patients with persistent major depression. In both study periods, a greater number of physician visits and prescription of apsychotropic medication (non-antidepressant) were independently associated with recognition.Conclusions: A longitudinal approach to measuring recognition of late-life depression in ambulatory care settings indicates that persistentmajor depression is more likely to be recognized than previously reported.© 2008 Elsevier Inc. All rights reserved.

Keywords: Aged; Depression; Primary care; Recognition

1. Introduction

Late-life depression is a common problem in ambulatorycare settings, associated with increased disability and use ofservices [1–3]. Despite the apparent effectiveness ofantidepressant and psychosocial treatments in this popula-tion [4], a recent meta-analysis found that, at all ages,depression is recognized by nonpsychiatric physicians in a

⁎ Corresponding author. Tel.: +1 514 345 3511x5060; fax: +1 514 7342652.

E-mail address: jane.mccusker@mcgill.ca (J. McCusker).

0163-8343/$ – see front matter © 2008 Elsevier Inc. All rights reserved.doi:10.1016/j.genhosppsych.2008.01.006

minority of cases [summary sensitivity of 36.4%, 95%confidence interval (CI)=27.9, 44.8] [5].

Prior research on recognition has two major limitations.First, most prior studies have been cross-sectional eventhough a longitudinal approach may be more relevant whenthe chronic, often fluctuating course of depression and thelongitudinal relationship between patients and their primaryphysicians are considered. Second, prior research has tendedto focus on patient factors associated with recognition (e.g.,greater severity of depressive symptoms [6], self-reporteduse of sleeping tablets) [6] and not on characteristics ofambulatory care. Although primary care physicians bearprimary responsibility for the recognition and treatment of

246 J. McCusker et al. / General Hospital Psychiatry 30 (2008) 245–251

late-life depression, little is known about how recognition ofdepression varies with the specialty of the primary physicianand the number of visits [7–9].

Thus, the purpose of this longitudinal observational study,using administrative databases linked to clinical data, was toexamine the recognition of depression in a cohort of oldermedical inpatients, in relation to the clinical course of thedepression, their ambulatory medical care and patientcharacteristics. We hypothesized that recognition of depres-sion would be more frequent among patients with thefollowing characteristics: a general practitioner as primaryphysician, more visits to the primary physician, prescribedpsychotropic medications other than antidepressants, female,cognitively intact, low comorbidity and better social support.This study extends a previous report, in which less than halfof the depressed patients in this cohort were recognized asdepressed by attending physicians during their hospital stay[10]. In the current study, we examine recognition inambulatory care settings during the year before and theyear after hospitalization.

2. Methods

2.1. Study sample

Methods of recruitment of the study sample have beendescribed in detail previously [11]. The study was conductedat two university-affiliated acute care Montreal hospitals,using random sampling from lists of consecutive admissionsof patients aged 65 and above from the emergency room tothe medical services (the usual admission route for none-lective admissions). The following patients were excluded:admissions to palliative care (because of expected survival ofless than 6 weeks), those who did not speak or understandEnglish or French or were unable to communicate and thosewho lived off the island of Montreal. Patients admitted to theintensive care or cardiac monitoring units were screenedafter transfer to a medical ward. Eligible patients werescreened using the Short Portable Mental Status Question-naire [12]; those with five or more errors (indicatingmoderate–severe cognitive impairment) [13] were excluded.Major and minor depression were diagnosed using theDiagnostic Interview Schedule (DIS; DSM-IV criteria) [14].All depressed patients and a random sample of nondepressedpatients were invited to participate in the longitudinalcomponent of the study. Among 1718 eligible patients,1686 received a screening DIS; the prevalence of major orminor depression was 27.9% (471/1686). Initial consentrates were 74.9% among patients with a depression diagnosisand 72.7% in the sample of 256 nondepressed patientsinvited to participate. At one of the hospitals, patients withmajor depression were invited to participate in a concurrentrandomized controlled trial that compared systematic detec-tion and multidisciplinary management with usual care [15].Patients in the intervention arm of the trial (n=43) wereexcluded from this study because their primary physician

was routinely informed of the diagnosis of depression;patients in the control arm were retained because theyreceived usual care and their physician was not informed of adiagnosis of depression by research staff.

Patients were interviewed at baseline (as soon aspossible after enrollment) and at 3, 6 and 12 months afterenrollment by research assistants who were blind to thepatients' initial depression diagnosis and study group.Similar rates of attrition due to death and other reasonswere found in the depressed and nondepressed cohorts. Forthe current study, the primary analyses were conducted inthe sample of 185 patients who had completed the baselineinterview and at least one follow-up, with a diagnosis ofmajor or minor depression either at baseline or at one ormore follow-up assessments [please note that 112 (60.5%)of the sample completed all follow-up assessments].

Other data sources included provincial hospital dis-charge, physician billing and prescription databases. Thestudy protocol was approved by the research ethics com-mittees of both hospitals and by the provincial body grantingaccess to the administrative databases (Commission d'accèsà l'information).

2.2. Measures

2.2.1. DepressionAt each interview, patients were classified as having

current (at least 2 weeks duration of symptoms) major, minoror no depression using the depressive disorders section of theDIS [14] with DSM-IV criteria using the “inclusive”approach (symptoms counted toward the diagnosis regard-less of the symptoms' origins, whether physical illness ordepression) [16]. Both diagnoses required the presence of atleast one core symptom (depression or loss of interest);major depression required four or more other symptoms andminor depression required one to three other symptoms. Theinterrater reliability of the DIS was assessed in a conveniencesample of 28 patients at intervals throughout the studyperiod, using independent simultaneous ratings by two ormore raters, including the study psychiatrist (M.C.). Valuesof the kappa coefficient were 0.78 (95% CI=0.52, 1.00) for adiagnosis of major depression versus minor or no depressionand 0.61 (95% CI=0.35, 0.87) for a diagnosis of either majoror minor depression versus no depression. The duration ofthe core symptoms (depressed mood and lack of interest) athospital admission was calculated from the DIS.

Based on the frequency of different patterns ofdepression diagnosis over time [17], we created twosummary measures of the course of depression. To examinethe relationship between recognition and course of depres-sion during the 12 months before admission, we used thebaseline DIS to create the following four groups: majordepression with core symptoms lasting 6 months or longer,major depression with core symptoms lasting less than6 months, minor depression and no depression. To examinethe relationship between recognition and course of depres-sion during the 12 months after admission, we used all

247J. McCusker et al. / General Hospital Psychiatry 30 (2008) 245–251

available DIS data to create the following three groups:persistent major depression (major depression at baselineand all follow-ups), fluctuating major depression (majordepression on at least one but not all assessments) andminor depression only (a diagnosis of minor depression atbaseline and/or follow-up, but without major depression atany point).

2.2.2. Recognition of depressionBased on three provincial databases, three indicators of

recognition of depression were used: a depression diagnosisat an ambulatory visit to a nonpsychiatric physician,treatment (antidepressant medication prescription) andreferral (to a psychiatrist). A global measure of recognitionwas defined as one or more of the above indicators. Theindicators, computed separately for the 12 months before andthe 12 months after admission, were defined as follows:

Diagnosis. ICD-9 diagnoses on physician claims fromambulatory care settings (private office or clinic), usingcriteria developed in a previous Quebec study (diagnosesof 311.0–311.9 or 300.4) [18].Treatment. Antidepressant medication prescriptions filledoutside the hospital were abstracted from the pres-cription database for the 12-month periods before andafter enrollment.Referral. Psychiatrist visits (excluding those during hospi-talization) were considered evidence of psychiatric referral.

2.3. Medical care

The primary physician was identified using claims fromambulatory care clinics during each of the two time periods(the year before and the year after admission) with apreviously validated algorithm [19] and was classified asgeneral practitioner, specialist and none. The number ofvisits to the primary physician and to other nonpsychiatristphysicians was determined for the two study periods.Psychotropic medication prescriptions (other than antide-pressants) were abstracted from the prescription database forthe 12-month periods before and after admission.

2.4. Patient characteristics

Cognitive impairment was defined as a score of less than24 on the Mini-Mental State Examination at baselineinterview [20]. Disability was defined as dependence inone or more basic activities of daily living 2 weeks beforehospital admission and was measured with the OlderAmericans Research and Service instrument [21]. Medicalcomorbidity was measured with the Charlson ComorbidityIndex, derived from chart review of diagnoses during the2 years before enrollment [22]. Social and demographicmeasures at baseline included age, gender, living arrange-ment (alone or with others), self-reported confidant (“aspecial person you know and feel intimate with, someoneyou share confidence and feelings with, someone you candepend on”) and informal caregiver (“a family member or

friend who provides the most assistance and is not paid”).Death during follow-up was measured as an indicator ofterminal illness.

2.5. Statistical methods

Descriptive analyses were conducted using standardapproaches. Associations between the two summary mea-sures of the course of depression and indicators ofrecognition were modeled separately for the 12 monthsbefore and the 12 months after admission using thegeneralized estimating equation (GEE) approach to theanalysis of correlated binary outcomes with covariates [23].The associations between depression profile (DP) and thebinary outcome variable recognition of depression duringeach 12-month time period (R12m) were modeled based onthe presence of one or more of the three indicators ofrecognition (diagnosis, treatment and referral), with specifictype of recognition (TR) as an auxiliary three-level covar-iate. We fitted a logistic regression model with outcomeR12m with TR and the potential covariates. Interactions of TRwith DP and potential covariates were also tested. Noticethat each patient is represented by three rows of data,corresponding to the three levels of TR; therefore, the threeoutcomes for a patient are necessarily correlated. Theparameters of the model were estimated by the GEEapproach, with unstructured correlation matrix to takeaccount of the intrapatient correlations.

Covariates considered in the GEE analyses during each ofthe two study periods included the following: patient age andgender, living arrangement (alone or with others), disability,cognitive impairment, comorbidity, confidant, informalcaregiver, type of primary physician (general practitioner,specialist, none), number of visits to the primary physicianand to other nonpsychiatrist physicians and non-antidepres-sant psychotropic medication prescriptions. Additionalcovariates considered for the models of recognition duringthe 12 months after admission were prior recognition (duringthe 12 months before admission) and death during thefollow-up period.

All calculations were performed in SAS (Version 9.1);the GENMOD procedure was used to implement theGEE approach.

3. Results

Characteristics of the sample are shown in Table 1. Themajority of patients were female and disabled and had ageneral practitioner as their primary physician. Patients madean average of about 5 visits to their primary physician and12 visits to other physicians and received at least onepsychotropic (non-antidepressant) medication prescriptionduring each of the two study periods (12 months before and12 months after admission).

Table 2 shows recognition rates during the two studyperiods by depression diagnostic group. In both time periods,

Table 2Recognition of depression during 12 months before and 12 months afterhospital admission (N=185)

Time period anddiagnostic group

n Indicator of recognition, n (%)

Diagnosis Treatment Referral Total

Depression diagnosis at admissionMajor depression,6+ months

57 9 (16) 30 (53) 10 (18) 32 (56)

Major depression,b6 months

32 4 (13) 7 (22) 1 (3) 9 (28)

Minor depression 43 2 (5) 11 (26) 2 (5) 12 (28)Depression onlyat follow-up

53 1 (2) 7 (13) 3 (6) 8 (15)

Depression course during 12 months after admissionPersistent majordepression

33 6 (18) 17 (52) 6 (18) 20 (61)

Fluctuating majordepression

102 8 (8) 32 (31) 11 (11) 37 (36)

Minor depression only 50 1 (2) 11 (22) 1 (2) 12 (24)

able 3nivariate and multivariable models of recognition of depression a during2 months before hospital admission (N=185)

redictors Univariatemodels

Multivariablemodel

OR 95% CI OR 95% CI

atient characteristics at hospital admissionAge (increase of 1 year) 0.96 0.92, 1.00 0.95 0.91, 1.00Female 1.78 0.92, 3.44 2.24 1.09, 4.62Lives alone 0.87 0.48, 1.57 0.82 0.43, 1.59Disabled 1.86 0.93, 3.71 1.13 0.53, 2.40Comorbidity(increase of 1 point)

1.07 0.90, 1.27 1.16 0.94, 1.43

Diagnosis at admissionMajor depression, 6+ months 6.69 2.74, 16.30 7.30 3.09, 17.25Major depression, b6 months 2.07 0.71, 6.06 2.45 0.76, 7.88Minor depression 2.01 0.74, 5.47 1.86 0.66, 5.24No depression 1.00 1.002 months before admissionPrimary physician visits(increase of 1 visit)

1.07 1.01, 1.13 1.08 1.01, 1.15

Speciality of primary physicianGeneral practitioner 1.00 1.00Specialist 0.15 0.04, 0.52 0.13 0.03, 0.56None 0.52 0.16, 1.75 1.49 0.45, 4.93Psychotropic medications b 4.77 2.45, 9.31 3.17 1.59, 6.34

R, odds ratio.a Recognition is defined as any of the following: depression diagnosis by

onpsychiatrist physician, antidepressant prescription or psychiatric referral.b Excluding antidepressants.

Table 1Characteristics of the study sample (N=185)

Variable Value

Patient characteristics at hospital admissionAge, mean (S.D.) 80.0 (7.1)Female, n (%) 119 (64.3)Lives alone, n (%) [missing, n=4] 87 (48.1)Disabled, n (%) [missing, n=3] 123 (67.6)Comorbidity, mean (S.D.) 1.3 (1.5)

12 months before admissionDiagnosis at admission, n (%)Major depression, 6+ months 57 (30.8)Major depression, b6 months 32 (17.3)Minor depression 43 (23.2)No depression 53 (28.7)Recognition of depression, n (%)Diagnosis 16 (8.7)Treatment 55 (29.7)Referral 16 (8.7)Any of above 61 (33.0)Type of primary physician, n (%)General practitioner 149 (80.5)Specialist 27 (14.6)None 9 (4.9)Primary physician visits, mean (S.D.) 5.1 (4.3)Other physician visits, mean (S.D.) 12.2 (11.0)Psychotropic medications, a n (%) 98 (53.0)

12 months after admissionDepression course, n (%)Persistent major depression 33 (17.8)Fluctuating major depression 102 (55.1)Minor depression only b 50 (27.0)Recognition of depression, n (%)Diagnosis 15 (8.1)Treatment 60 (32.4)Referral 18 (9.7)Any of above 69 (37.3)Primary physician visits, mean (S.D.) 4.7 (4.3)Other physician visits, mean (S.D.) 11.8 (10.3)Psychotropic medications, a n (%) 100 (54.1)Type of primary physician, n (%)General practitioner 138 (74.6)Specialist 32 (17.3)None 15 (8.1)

a Excluding antidepressants.b With or without fluctuation, but without major depression.

248 J. McCusker et al. / General Hospital Psychiatry 30 (2008) 245–251

treatment was the most frequent indicator, with diagnosisand referral each making only a small contribution to overallrecognition. Among the 60 depressed patients who weretreated, specific antidepressants used during follow-up(some patients received more than one type) includedSSRIs (75%), tricyclics (23%) and others (5%). Allrecognition indicators rose sharply with severity of depres-sion (major vs. minor depression) and with duration orpersistence of depression. However, the overall recognitionrate did not increase further among patients with persistentmajor depression who had seen their primary physician atleast five times during the study period.

Tables 3 and 4 show the results of the univariate andmultivariable logistic regression analyses for the two timeperiods. Cognitive impairment, presence of a confidant or

an informal caregiver, number of visits to physicians otherthan the primary physician and death are not shown ineither of the tables because they did not contribute to themodels. During the 12 months before admission (Table 3),female patients, those with major depression for 6 monthsor longer, those with general practitioner versus a specialistprimary physician, those who had made a greater number ofvisits to the primary physician and those with a psycho-

TU1

P

P

1

O

n

Table 4Univariate and multivariable models of recognition of depression a during 12 months after hospital admission (N=185)

Predictors Univariate models Multivariable model A b Multivariable model B c

OR 95% CI OR 95% CI OR 95% CI

Patient characteristics at hospital admissionAge (increase of 1 year) 0.97 0.94, 1.01 0.98 0.94, 1.01 0.99 0.96, 1.03Female 1.04 0.59, 1.84 1.31 0.70, 2.48 0.94 0.51, 1.74Lives alone 0.72 0.41, 1.24 0.81 0.45, 1.46 1.07 0.60, 1.91Disabled 1.74 0.93, 3.25 1.33 0.69, 2.56 1.29 0.66, 2.54Comorbidity (increase of 1 point) 1.05 0.88, 1.24 1.13 0.93, 1.37 1.02 0.82, 1.27Prior recognition (previous 12 months) 7.32 4.05, 13.24 – 7.07 3.60, 13.9012 months after admissionDepression coursePersistent major depression 4.83 2.22, 10.49 5.40 2.44, 11.95 2.29 0.93, 5.60Fluctuating major depression 2.12 1.06, 4.26 2.22 1.06, 4.62 1.43 0.66, 3.09Minor depression only 1.00Primary physician visits (increase of 1 visit) 1.07 1.00, 1.14 1.08 1.00, 1.17 1.09 1.02, 1.16Type of primary physicianGeneral practitioner 1.00 1.00 1.00Specialist 0.98 0.48, 2.03 1.25 0.58, 2.70 1.83 0.82, 4.06None 0.46 0.13, 1.70 0.68 0.19, 2.52 0.50 0.12, 2.14Psychotropic medications d 3.00 1.69, 5.32 2.64 1.39, 5.01 2.49 1.33, 4.67

OR, odds ratio.a Recognition is defined as any of the following: depression diagnosis by nonpsychiatrist physician, antidepressant prescription or psychiatric referral.b Includes all predictors except prior recognition.c Includes all predictors.d Excluding antidepressants.

249J. McCusker et al. / General Hospital Psychiatry 30 (2008) 245–251

tropic medication (non-antidepressant) prescription weresignificantly more likely to be recognized in both univariateand multivariable analyses. There were no significantinteractions with these variables and the specific indicatorsof recognition.

During the 12 months after admission, persistent majordepression, a greater number of primary physician visits andprescription of a non-antidepressant psychotropic medica-tion were significantly associated with recognition in bothunivariate and multivariable analyses (Table 4). Fluctuatingmajor depression was also more likely to be recognized butnot after adjustment for prior recognition (Model B). Therewas no statistically significant interaction between depres-sion diagnosis and number of primary physician visits duringeither time period. Neither patient gender nor type of primaryphysician was associated with recognition even afteradjustment for prior recognition. There were interactionswith the specific recognition indicator for patient age, livingalone and number of primary physician visits. Specifically,younger patients and those who lived alone were more likelyto have a psychiatric referral; patients with a greater numberof primary physician visits were more likely to have adepression diagnosis.

4. Discussion

This article reports the results of a longitudinal study ofthe recognition of late-life depression in ambulatory caresettings, using administrative databases linked to researchassessments of depression in a sample of older medical

inpatients with at least one diagnosis of major or minordepression during the 12-month study period. The two maincontributions to knowledge are as follows: (a) the relation-ship of recognition to the duration or persistence of thedepression and opportunities for recognition by the primaryphysician and (b) the importance of treatment rather thandiagnosis as an indicator of recognition when usingadministrative databases.

Cross-sectional studies are unable to distinguish betweendifferent patterns of depression persistence over time. Alongitudinal approach, we believe, is particularly importantin studying the recognition of chronic conditions such asdepression in ambulatory care settings, where ongoingcontact with patients over time offers multiple opportunitiesfor assessment but where multiple morbidities and limitedpatient contact time mean that a particular problem may notreceive attention at every visit. During the 12 months afterhospital admission, the recognition rate for fluctuatingmajor depression, the most common form of depression inthis study, was low (36%), similar to rates of recognitionreported in other studies [5,24,25]. In contrast, therecognition rate among patients with persistent majordepression (61%) was significantly higher than thatreported in cross-sectional studies. A greater number ofvisits to the primary physician was associated indepen-dently with higher rates of recognition; this may reflectincreased opportunities for the physician to observe andinteract with the patient.

During both time periods, treatment was the majorindicator of recognition, accounting for 85% or more ofrecognized cases. The relative importance of treatment as an

250 J. McCusker et al. / General Hospital Psychiatry 30 (2008) 245–251

indicator of recognition in this study may be due to theunderrecording of depression in administrative databases incomparison with patient charts.

This study also investigated medical care and patientcharacteristics associated with recognition of depression.Consistent with one prior study [6], patients receivingprescriptions for non-antidepressant psychotropic medica-tions were more likely to be recognized, perhaps due toincreased physician awareness of psychological symptomsfor which these medications were prescribed. There werediscrepant results from the two study periods: women(consistent with previous cross-sectional research) [25] andthose with a general practitioner were more likely to berecognized during the 12 months before admission, butthere was no effect of these factors during the 12 monthsafter admission, even after adjustment for prior recognition.A medical hospitalization may reduce the effects of thesevariables, for reasons that are unclear. Cognitive impair-ment, comorbidity and terminal illness were not associatedwith recognition.

This study has several limitations. First, the study samplewas not representative of all older people with depression.The sample comprised medically ill patients admitted totwo study hospitals through the emergency room; itexcluded the most severely ill patients who were unableto participate, those with more than mild cognitiveimpairment and patients admitted on an elective basis.Second, the indicators of recognition derived from admin-istrative data each had limitations: physicians could codeonly one diagnosis per visit, and the reasons forantidepressant prescriptions and psychiatric referral wereunknown. These limitations may have lowered therecognition by diagnosis and increased recognition bytreatment. Third, the sample size was modest, limiting thestatistical power of the study. Fourth, an assessment of theadequacy of antidepressant treatment was beyond the scopeof this article. Fifth, although the longitudinal groupingsused in this study have some face validity, they are, to someextent, arbitrary.

The results underline the importance of the primaryphysician in the recognition of depression in seniors.While the number of primary physician visits wassignificantly related to recognition (particularly to diag-nosis) in both time periods, the number of visits to othernonpsychiatric physician was not related to recognition.During the 12 months before admission (but not duringfollow-up), general practitioners were significantly morelikely than specialist primary physicians to recognizedepression. The role of specialist primary physicians maydiffer from that of general practitioners, particularly duringthe period following medical hospitalization. Overall, itappears that primary physicians are aware of the majorityof older patients with persistent major depression, but asubstantial minority (about 40%) of these patients andmost of the patients with fluctuating major depressionremain unrecognized and, therefore, presumably, untreated,

even when their primary physician has seen them at leastfive times during the year. These patients are likely to havea poor prognosis [17] and may benefit from better recog-nition and treatment.

Acknowledgments

This work has been presented, in part, at the AnnualMeeting of the CanadianAssociation of Gerontology, Calgary,Alberta, November 1–3, 2007. The researchwas funded by theCanadian Institutes for Health Research and the St. Mary'sHospital Foundation.

References

[1] Beekman ATF, Geerlings SW, Deeg DJH, et al. The natural history oflate-life depression. Arch Gen Psychiatry 2002;59:605–11.

[2] Beekman AT, Penninx BW, Deeg DJ, et al. Depression and physicalhealth in later life: results from the Longitudinal Aging StudyAmsterdam (LASA). J Affect Disord 1997;46(3):219–31.

[3] Büla CJ, Wietlisbach V, Burnand B, Yersin B. Depressive symptoms asa predictor of 6-month outcomes and services utilization in elderlymedical inpatients. Arch Intern Med 2001;161:2609–15.

[4] McCusker J, Cole M, Keller E, Bellavance F, Berard A. Effectivenessof treatments of depression in older ambulatory patients. Arch InternMed 1998;158:705–12.

[5] Cepoiu M, McCusker J, Cole M, et al. Recognition of depression bynon-psychiatric physicians— a systematic literature review and meta-analysis. J Gen Intern Med (accepted).

[6] Pfaff JJ, Almeida OP. A cross-sectional analysis of factors thatinfluence the detection of depression in older primary care patients.Aust N Z J Psychiatry 2005;39:262–5.

[7] Spiegel JS, Rubenstein LV, Scott B, Brook RH. Who is the primaryphysician? N Engl J Med 1983;308(20):1208–12.

[8] Aiken LH, Lewis CE, Craig J, et al. The contribution of specialists tothe delivery of primary care. N Engl J Med 1979;300(24):1363–70.

[9] Statistics Canada. Canadian Community Health Survey. Cycle 2.1.Ottawa, Ontario: Health Statistics Division; 2003.

[10] CepoiuM, McCusker J, Cole M, Sewitch M, Ciampi A. Recognition ofdepression in older medical inpatients. J Gen Intern Med 2007;22(5):559–64.

[11] McCusker J, Cole M, Dufouil C, et al. The prevalence and correlates ofmajor and minor depression in older medical inpatients. J Am GeriatrSoc 2005;53(8):1344–53.

[12] Pfeiffer E. A short portable mental status questionnaire for theassessment of organic brain deficit in elderly patients. J AmGeriatr Soc1975;23(10):433–41.

[13] Erkinjuntti T, Wikstrom J, Palo J, Autio L. Dementia among medicalinpatients: evaluation of 2000 consecutive admissions. Arch InternMed 1986;146:1923–6.

[14] Robins LN, Helzer JE, Croughan J, Ratcliff KS. National Institute ofMental Health Diagnostic Interview Schedule: its history, character-istics, and validity. Arch Gen Psychiatry 1981;38:381–9.

[15] Cole MG, McCusker J, Elie M, et al. Systematic detection andmultidisciplinary care of depression in older medical inpatients: arandomized trial. Can Med Assoc J 2006;174(1):38–44.

[16] Koenig HG, George LK, Petersen BL, Pieper CF. Depression inmedically ill hospitalized older adults: prevalence, characteristics, andcourse of symptoms according to six diagnostic schemes. Am JPsychiatry 1997;154(10):1376–83.

[17] Cole M, McCusker J, Ciampi A, et al. The prognosis of a major andminor depression in older medical inpatients. Am J Geriatr Psychiatry2006;14(11):966–75.

251J. McCusker et al. / General Hospital Psychiatry 30 (2008) 245–251

[18] SewitchMJ, Blais R, Rahme E, Galarneau S, Bexton B. Pharmacologicresponse to a diagnosis of late-life depression: a population study inQuebec. Can J Psychiatry 2006;51(6):363–70.

[19] McCusker J, Dendukuri N, Tousignant P, et al. Rapid two-stageemergency department intervention for seniors: impact on continuityof care. Acad Emerg Med 2003;10:233–43.

[20] Tombaugh TN, McIntyre NJ. The Mini-Mental State Examination: acomprehensive review. J Am Geriatr Soc 1992;40(9):922–35.

[21] Fillenbaum GG. Multidimensional functional assessment of olderadults: the Duke Older Americans Resources and Services procedures.New Jersey: Lawrence Erlbaum Associates Inc; 1988.

[22] Charlson ME, Pompei P, Ales KL, MacKenzie RC. A new method ofclassifying prognostic comorbidity in longitudinal studies: develop-ment and validation. J Chronic Dis 1987;40(5):373–83.

[23] SAS Institute Inc. Longitudinal data analysis with discrete andcontinuous responses. Cary, NC: SAS Institute Inc; 2002.

[24] Volkers AC, Nuyen J, Verhaak PF, Schellevis FG. The problem ofdiagnosing major depression in elderly primary care patients. J AffectDisord 2004;82:259–63.

[25] Crawford MJ, Prince M, Menezes P, Mann AH. The recognition andtreatment of depression in older people in primary care. Int J GeriatrPsychiatry 1998;13:172–6.