Stroke: A National Survey
Marie Eriksson, MSc; Kjell Asplund, MD, PhD; Eva-Lotta Glader, MD, PhD; Bo Norrving, MD, PhD;
Birgitta Stegmayr, PhD; Andreas Tere´nt, MD, PhD; Kerstin Hulter Åsberg, MD, PhD;
Per-Olov Wester, MD, PhD; for The Riks-Stroke Collaboration
Background and Purpose—Depression after stroke is often described as underdiagnosed and undertreated. However, there are few data on self-reported depression and use of antidepressants in stroke patients at large.
Materials and Methods—In the Swedish national quality assessment register, Riks-Stroke, 15 747 stroke survivors are recorded. They were asked about depressive mood and antidepressant treatment 3 months after stroke. Age-specific prevalence of antidepressant use after stroke was calculated.
Results—At 3 months after stroke, 12.4% of male and 16.4% of female stroke survivors reported that they always or often felt depressed. In a multiple logistic regression model, female sex, age younger than 65 years, living alone, having had a recurrent stroke, being dependent on others, and institutional living 3 months after stroke were independent predictors of self-reported depression. Antidepressant medication was used by 22.5% of men and 28.1% of women who had had a stroke. Of patients using antidepressant drugs, 67.5% did not report depressive mood. However, 8.4% of the entire cohort reported depressive mood but no treatment with antidepressants. When compared with the general population, approximately twice as many of the stroke patients were using antidepressant treatment.
Conclusions—In this national survey, 1 in 7 patients reported that they felt depressed and the use of antidepressant drugs after stroke was common. The widespread use of antidepressants challenges the contention that antidepressants are generally underused after stroke. However, the substantial proportion reporting depressive mood but not using treatment with antidepressants suggests that patient selection for treatment should be more precise. (Stroke. 2004;35:936-941.)
Key Words: stroke 䡲 depression 䡲 antidepressive agents
D
epression after stroke is a well-defined entity that isserious and treatable. It has severe implications for quality of life1–3 and is strongly associated with excess
mortality during the first years after stroke.4 – 6 It may be
reactive to the disabilities caused by the stroke and the profound changes in basic aspects of life conferred by stroke; however, in many patients, depression after stroke also seems to have a direct physiological and anatomical correlate.3,7,8
Tricyclic antidepressants and serotonin uptake inhibitors have, in randomized controlled trials, been shown to be superior to placebo to alleviate depression after stroke.3It is
a widely held contention that depression after stroke is an underdiagnosed and undertreated condition. However, there is little information available outside the setting of research cohorts to support this sentiment. As reported later in this article, antidepressant agents are widely used in the popula-tion at large and, during the stroke-prone ages, antidepressant drugs are now used by 1 in every 10 men and 1 in every 5 women in Sweden. Rapid increases in the use of antidepres-sants among elderly people have been reported from many
countries, including Australia,9 Italy,10 Sweden,11 United
Kingdom,12and the United States.13,14It seems that, after all,
depression is recognized and treated much more frequently today than previously. To what extent this applies to patients with depression after stroke is unknown.
Riks-Stroke, the national register for assessment of the quality of stroke care in Sweden,15was initiated in 1994. All
84 hospitals that care for acute stroke patients participate and ⬎20 000 patients are included each year. From 2001, ques-tions concerning depression and use of antidepressants have been included in the 3-month follow-up. The objective of this study was to describe and analyze, in a large national cohort, self-reported depression after stroke, its risk factors, and treatment with antidepressant drugs.
Materials and Methods
Study Population
In 2002, 22 530 patients treated in 84 hospitals were registered in Riks-Stroke, the Swedish national register for quality assessment of
Received September 9, 2003; accepted December 31, 2003.
From Department of Public Health and Clinical Medicine (M.E., K.A., E.-L.G., B.S., P.-O.W.), Umeå University, Sweden; Department of Clinical Neuroscience (B.N.), Lund University, Sweden; Department of Medical Science (A.T.), Uppsala University, Sweden; Department of Medicine (K.H.A.), Enko¨ping Hospital, Sweden.
Correspondence to Marie Eriksson, Department of Medicine, University Hospital, SE-901 85 Umeå, Sweden. E-mail [email protected] © 2004 American Heart Association, Inc.
Stroke is available at http://www.strokeaha.org DOI: 10.1161/01.STR.0000121643.86762.9a
stroke care.15,16Of these, 2679 (11.9%) died during the hospital stay
and another 1301 (5.8%) died later during the 3-month follow-up.
Outcome Variables
Each hospital conducted a 3-month follow-up of their stroke patients and data were submitted to the Riks-Stroke national coordinating center using an Internet-based system (details are given at the Riks-Stroke web site: http://www.riks-stroke.org/files/ENGcontent-s.html). Most hospitals received the 3-month follow-up question-naire in written form and, if necessary, the staff obtained comple-mentary information by telephone interviews. In 27 of the 84 hospitals, a majority of the follow-up information (⬎50%) was obtained by telephone interviews. Of the 15 747 patients that were followed-up in this study, 4561 (29.0%) answered the questionnaire in writing by themselves, 3677 (23.4%) answered in writing with help from a family member, 4658 (29.6%) answered by telephone, 349 (2.2%) answered during a visit to the hospital, 1559 (9.9%) had a caregiver who answered, and 942 (6.0%) answered in some other way.
One of the questions at the 3-month follow-up of the patients who had a stroke in 2002 was “Do you feel depressed?” Five fixed response alternatives were given: “never/almost never,” “some-times,” “often,” “all the time,” and “do not know.” Patients who answered “often” or “all the time” were considered to have self-reported depression and patients who answered “do not know” were considered to be missing. The variable self-reported depression (yes/no) was the primary outcome variable in this study. One question concerned treatment of depression (yes/no/do not know). Age (64 or younger, 65 to 74, 75 to 84, and 85 or older), sex, place of living, cohabitant status, activities of daily living (ADL) perfor-mance and use of antidepressants 3 months after stroke were analyzed as co-variates. Self-reported ADL proficiency was esti-mated by a 3-item instrument that has been shown to correlate closely with the Barthel index.16
Validation of Self-Reported Depression in Riks-Stroke
The Riks-Stroke question on depression was validated in a separate study in which 36 patients (one-third each with mild, moderate, and severe neurological deficits) were interviewed approximately 3 months after they had a stroke. Self-reported depression in Riks-Stroke was compared with depression (mild or severe) as defined by the Prime-MD instrument.17The 2 instruments correlated reasonably
well (rs⫽0.645; P⬍0.001). When depression was not present accord-ing to the Prime-MD criteria (n⫽22), self-reported depression was not present by the Riks-Stroke classification in all instances (speci-ficity⫽100%). Of the 13 patients that had mild depression according to Prime-MD, 5 were correctly classified using Riks-Stroke criteria (sensitivity⫽38%).
Sales of Antidepressant Drugs
Information on the sales of antidepressants (ATC code N06A) in the general Swedish population in 2002 was obtained from Apoteket AB, Stockholm (the Swedish pharmacy chain having exclusive rights to sell drugs prescribed by a physician). The sales were expressed as defined daily doses per 1000 inhabitants. Defined daily doses for antidepressant agents were those defined by the WHO Collaborating Centre for Drug Statistics Methodology (available at: http://www.whocc.no/atcddd). The point prevalence (%) of antide-pressant use was then estimated as defined daily.
Statistical Methods
Univariate logistic regression was used to test for associations between self-reported depression and the factors of sex, age, living alone at follow-up, institutional living at follow-up, primary ADL function at follow-up, stroke subtype, level of consciousness on admission, and recurrent stroke. To simultaneously test the factors, multiple logistic regression was used. Results are presented with estimated odds ratios and corresponding 95% confidence intervals. The use of antidepressants was analyzed using the same methods and
factors. The statistical package SAS, release 8.2, was used for the analyses.
Results
Missing Data
Among the 18 550 patients still alive 3 months after stroke, 2803 (15.1%) were lost to follow-up. Patients lost to follow-up were more often women (50.6% versus 47.9%), older (mean age 78 versus 76 years), living alone (54.8% versus 45.3%), and ADL-dependent (11.6% versus 7.0%) prior to their stroke. Of the 15 747 patients that were followed up, responses to the question concerning depressive mood was missing for 1748 (11.1%). Thus, data on self-reported depression at 3 months’ follow-up were available in 13 999 patients (Figure 1). Many of the patients with missing data on mood (945 out of 1748; 54.1%) had not answered the questionnaire by themselves. Hence, older, ADL-dependent patients and patients not living at home were over-represent-ed in that group. Data concerning use of antidepressants were available for 11 687 (74.2%) of the patients who were followed-up (Figure 1). The majority (77%) of the patients who did not answer the questions concerning antidepressants were identical with those who did not answer the depressive mood question. The remainder of the missing group did not differ substantially with respect to age (mean 74.4 versus 74.0 years), sex (53.5% versus 52.5% men), and proportion being ADL-independent at follow-up (76.0% versus 75.9%) com-pared with those who answered the antidepressant question. Self-Reported Depression
At the 3-month follow-up, 1999 patients (14.3%) reported that they felt depressed (12.4% of the men and 16.4% of the
Figure 1.Patients included in description of patients with self-reported depression (a), description of the relationship between self-reported depression and reported use of antidepressants (b), and comparison of use of antidepressants in stroke patients versus the general population (c).
women). Female sex, having had recurrent stroke, and not being fully conscious on admission were all associated with self-reported depression in the univariate analysis (Table 1). Being dependent on others in ADL, institutional living at 3 months after stroke, and, among those living at home, living alone, were also factors associated with self-reported depres-sion (Table 1). Age, stroke subtype, and whether the patient had been treated in a stroke unit during the acute phase had little impact on self-reported depression.
Including the aforementioned variables, a multiple logistic regression verified the results from the univariate analysis, with the exception of lowered level of consciousness on admission that was no longer significantly associated with self-reported depression. In addition, after adjustment for co-variates, younger patients (younger than 65 years) were significantly more likely than elderly patients to report depressive mood (Table 2).
To further investigate the implied association between younger age and depression, a separate analysis was per-formed with the least severely affected patient group, ie, those who were ADL-independent and were living at home without community service at the follow-up. Also, in this subgroup, younger patients were significantly more likely to report that they felt depressed than were older patients, thereby verifying the overall results from the multiple logistic regression (data not shown).
Antidepressant Medication
At the follow-up, answers were available for self-reported depression and use of antidepressant drugs in 11 292 patients. As shown in Table 3, approximately half (49.1%) who reported depressive mood were using antidepressants. The 943 patients who felt depressed but were not using drug treatment represent 8.4% of the entire population. However, TABLE 1. Proportion Self-Reported Depression and Odds Ratio Estimates of
Self-Reported Depression Using Univariate Logistic Regression
Variable n Depressed (%) Odds Ratio 95% CI for OR Lower Upper Sex Male 7378 12.4 ref. Female 6621 16.4 1.38 1.26 1.52 Age (y) ⱕ64 2640 15.1 ref. 65–74 3598 12.4 0.80 0.69 0.92 75–84 5578 14.1 0.93 0.81 1.05 ⱖ85 2183 16.7 1.12 0.96 1.31 Number of strokes
First ever 10 150 13.6 ref.
Recurrent 3641 16.4 1.25 1.12 1.38
Level of consciousness on admission
Alert 11 892 13.7 ref. Impaired 1981 20.2 1.60 1.38 1.85 Stroke subtype Ischemic 12 034 14.4 ref. Hemorrhagic 1366 13.7 0.94 0.80 1.11 Undetermined 599 13.4 0.92 0.72 1.17 Stroke unit care
No 2945 13.6 ref.
Yes 10769 14.5 1.08 0.96 1.21
Primary ADL function at follow-up
Independent 10 562 10.9 ref.
Dependent 3348 24.8 2.69 2.44 2.97
Living at home at follow-up
Yes 11 232 11.8 ref.
No 2684 24.5 2.42 2.18 2.69
Living alone at follow-up (among those living at home)
No 6758 10.4 ref.
Yes 4455 13.8 1.38 1.23 1.55
of those treated with antidepressant drugs, less than one-third (911 of 2806; 32.5%) reported depressive mood. In the subgroup of patients reporting depressive mood, being a woman, living in an institution, and being ADL-dependent significantly increased the likelihood of using an antidepres-sant (data not shown).
When patients who used antidepressants were compared with those who were depressed but did not report the use of antidepressant drugs, it emerged that patients with severe stroke sequelae (living in an institution and ADL-dependent) were more likely to use antidepressive drugs (Table 4). Patients in the oldest age category (85 years or older) were significantly less likely to report use of antidepressants.
In comparisons of the use of antidepressants in stroke patients versus the general populations, we used data on all 11 687 patients with information on drug use, ie, we also used data on use of antidepressants from 395 who had not responded to the question on mood (Figure 1). Use of antidepressants was much more common in stroke patients as compared with the general population (Figure 2). The differ-ence was most evident among younger stroke patients. Among men, the relative use of antidepressants in stroke patients versus general population decreased from 4.5 in the 45- to 64-year-old group to 1.3 in the 85 and older age group.
Among women, the corresponding relative use was 2.7 and 1.2, respectively. Use of antidepressant drugs was more common in women than in men of all ages among stroke patients and in the general population (Figure 2).
Discussion
The strength of this study is that it is a very large study population using stroke patients in an entire country during a 1-year period. The most important weakness is that it is based on self-reported data and not on strict diagnostic criteria for depression and confirmed use of antidepressants.
A single question to screen for depression in large cohorts (as in the Riks-Stroke register) has been shown to be quite specific in diverse populations,18including patients who have
had strokes.19 In the present study, the prevalence of
self-reported depression at 3 months after stroke was 12% in men and 16% in women This is considerably lower than the 32% to 53% reported at 3 to 4 months after stroke in previous studies that have used strict diagnostic criteria applied either by a psychiatrist7,20,21 or by a questionnaire2. These
high-prevalence estimates include minor and major depression, and the Riks-Stroke estimates are more in agreement with the 10% to 20% prevalence of major depression reported after stroke.9 Comparison of the responses to the simple
Riks-Stroke question on depressive mood with Prime-MD, an established instrument to screen for depression,17 although
not validated specifically in stroke patients, indicated that the Riks-Stroke question had a high specificity but a low sensi-tivity for detecting depression. The proportion of patients in the Riks-Stroke register reporting that they always or often felt depressed 3 months after stroke is therefore probably an underestimate of the true prevalence of depression after TABLE 2. Odds Ratio Estimates of Self-Reported Depression
Using Multiple Logistic Regression
Variable Odds Ratio 95% CI for OR Lower Upper Female 1.30 1.17 1.44 Age (ref.ⱕ64) 65–74 0.68 0.59 0.80 75–84 0.64 0.55 0.73 ⱖ85 0.61 0.51 0.73 Recurrent strokes 1.13 1.02 1.27 Impaired consciousness on admission 1.09 0.93 1.28 Stroke subtype (ref. ischemic)
Hemorrhagic 0.84 0.71 1.00
Undetermined 0.91 0.70 1.18
Stroke unit care 1.06 0.94 1.20 ADL-dependent at follow-up 2.34 2.05 2.67 Living situation at follow-up
(ref. at home, not alone)
At home, alone 1.48 1.30 1.67 In institution 1.73 1.48 2.05 ref. indicates reference category.
TABLE 3. Reported Use of Antidepressant Drugs vs Self-Reported Depression in 11 292 Stroke Patients at 3-Month Follow-up
Use of Antidepressants Yes (n⫽2806) No (n⫽8486) Total (n⫽11 292) Self-reported depression 911 943 1854 No self-reported depression 1895 7543 9438
TABLE 4. Odds Ratio Estimates of Use of Antidepressants Using Multiple Logistic Regression*
Variable Odds Ratio 95% CI for OR Lower Upper Female 1.15 0.98 1.35 Age (ref.ⱕ64) 65–74 0.96 0.76 1.22 75–84 0.88 0.71 1.09 ⱖ85 0.52 0.39 0.68 Recurrent strokes 1.05 0.88 1.24 Impaired consciousness on admission 1.15 0.90 1.47 Stroke subtype (ref. ischemic)
Hemorrhagic 0.97 0.74 1.27
Undetermined 0.96 0.65 1.41
Stroke unit care 1.08 0.90 1.31 ADL-dependent at follow-up 1.53 1.25 1.87 Living situation at follow up
(ref. at home, not alone)
At home, alone 0.81 0.67 0.97 In institution 1.38 1.10 1.73 ref. indicates reference category.
*Comparing patients who used antidepressants (n⫽2806) with those who reported depressive mood but did not use antidepressants (n⫽943).
stroke. Our prevalence rates are thus likely to reflect only more severe states of depression after stroke (major depres-sion). The high specificity implies that analyses of clinical factors associated with depression after stroke are not con-founded by a large proportion of patients without depressive mood. It should be emphasized that the diagnosis of depres-sion may be difficult when aphasia, anosognosia, and other cognitive dysfunctions are present after stroke. The diagnos-tic precision is likely to be less in a large-scale study using a simple question than in the clinical setting. Although the absolute prevalence rates of depression after stroke should be taken as crude estimates, the diagnostic imprecision would occur across age and sex subgroups. Relative differences between groups of stroke patients are likely to be more accurate.
Extensive validation studies indicate that Riks-Stroke cov-ers approximately 70% of all acute stroke patients in Swe-den.16 Less than 5% of acute stroke patients, mostly those
already in institutional care, are not admitted to hospital.22–25
Patients with the most severe strokes dying early after onset are underrepresented in Riks-Stroke,16,23but this should not
affect the present results at 3-month follow-up. Old age and not being admitted to a stroke unit also predict non-inclusion into the Riks-Stroke register.16,23The effect of these selection
factors on the results presented here is probably not great. The mean age in the Riks-Stroke patients (76 years) is as high, or higher than, as reported from population-based epidemiolog-ical studies in Sweden22–25 and high age has, per se, little
impact on the prevalence of self-reported depression.26Our
results also indicate that stroke unit care has no major impact on the occurrence of depression after stroke; therefore, any over-representation in the Riks-Stroke register of patients treated in stroke units should not introduce any major bias.
Antidepressant treatment was reported by one quarter of the patients at 3 months after stroke. In other settings, the accuracy of self-reported antidepressant use has been re-ported to be good.27In the present cohort of stroke patients of
relatively old age (mean 76 years), underreporting rather than over-reporting of drug use is likely. Some of the previous studies on a limited number of patients have used strict
diagnostic criteria for depression, such as III or DSM-IV, whereas this study reports on self-reported depression. With the frequent use of antidepressant medication, it is likely that most of the decisions to prescribe these drugs are based on general clinical impression and what patients report rather than on strict diagnostic criteria.
The type of antidepressant drugs used was not recorded in Riks-Stroke. In Sweden, selective serotonin reuptake inhibi-tors (SSRIs) account for 76% and other newer drugs for 18% of the total sales of antidepressant drugs (data from Apoteket AB). In view of the adverse reaction profiles of tricyclic antidepressants in elderly people, it is reasonable to assume that only a minority of stroke patients are treated with this class of drugs. The limited data available from randomized trials on SSRIs in the treatment of depression after stroke suggest a moderate beneficial effect, but a considerable proportion of patients with depression after stroke may also recover spontaneously.3The two-thirds using antidepressant
treatment not reporting depressive mood in the present study may thus be because of spontaneous recovery, effect of drug treatment, or poor ability of the Riks-Stroke question to detect mild forms of depression.
One third of the patients using antidepressant treatment reported depressive mood, suggesting insufficient response to the treatment. Riks-Stroke does not include information on when antidepressant drug treatment was initiated or doses used in individual patients. It is therefore possible that, in some patients, treatment times were too short or the dosages were too low for the medication to be fully effective. Even in randomized trials, treatment failures are common.3Because
antidepressants are widely used in elderly people in Sweden, it is also possible that many depressive or dysthymic people with poor response to antidepressants were already using drug treatment before stroke. Moreover, adversity of antide-pressant drugs may have caused early termination of the treatment, an issue that has not been addressed in large clinical trials.
A sizable proportion of patients (8%) reported depressive mood but were not using antidepressant therapy at 3 months after stroke. This may reflect: (1) failure to accurately
Figure 2.Prevalence of depression after stroke and use of antidepressants 3 months after stroke and of antidepressants in the general population in Sweden.
diagnose depression after stroke; (2) a wait-and-see attitude among physicians after diagnosing depression after stroke; or (3) inadequate follow-up of stroke patients after discharge from hospital.
We conclude that in a nationwide stroke population survey, female sex, age younger than 65 years, living alone or in an institution, and being ADL-dependent were factors associated with self-reported depression after stroke. One quarter of all stroke patients were using antidepressant therapy at 3 months, which suggests that this therapy is now liberally used after stroke. More importantly, we observed that approximately half of the patients reporting depressive mood did not receive antidepressant therapy at 3 months after stroke. This raises concerns that clinical practices to detect and treat depression after stroke are still suboptimal. Studies using more detailed methodology to assess diagnostic criteria for depression after stroke and the timing, intensity, and effect of treatment in routine clinical practice are warranted.
Appendix
The Riks-Stroke Collaboration includes Alingsås Hospital; Arvika Hospital; Avesta Hospital; Bollna¨s/So¨derhamn Hospital; Borås Hos-pital; Danderyd HosHos-pital; Enko¨ping HosHos-pital; Fagersta HosHos-pital; Falko¨ping Hospital; Falun Hospital; Finspång Hospital; Ga¨llivare Hospital; Ga¨vle/Sandviken Hospital; Halmstad Hospital; Helsing-borg Hospital; Huddinge Hospital, Stockholm; Hudiksvall Hospital; Ha¨rno¨sand Hospital; Ha¨ssleholm Hospital; Ho¨glandssjukhuset, Eksjo¨-Na¨ssjo¨; Kalmar Hospital; Karlskrona Hospital; Karolinska Hospital, Stockholm; Karlstad Hospital; Kristianstad Hospital; Ka¨rn-sjukhuset/Sko¨vde; Kalix Hospital; Karlshamn Hospital; Karlskoga Hospital; Kiruna Hospital; Kristinehamn Hospital; Kullbergska Sjukhuset/Katrineholm; Kunga¨lv Hospital; Ko¨ping Hospital; Land-skrona Hospital; Lidko¨ping Hospital; Lindesberg Hospital; Linko¨p-ing University Hospital; Ljungby Hospital; Ludvika Hospital; Lund University Hospital; Lycksele Hospital; Malmo¨ University Hospital; Mariestads Hospital; Mora Hospital; Motala Hospital; Ma¨larsjukhu-set, Eskilstuna; Norrko¨ping Hospital; Norrta¨lje Hospital; Nyko¨ping Hospital; NA¨ L Hospital, Trollha¨ttan; Oskarshamn Hospital; Piteå Hospital; Ryhov Hospital, Jo¨nko¨ping; Sahlgrenska University Hos-pital, Sahlgrenska, Mo¨lndal, O¨ stra; Sala Hospital; Skene Hospital, Simrishamn Hospital; Skellefteå Hospital; Sollefteå Hospital; St Go¨ran Hospital, Stockholm; Sunderbyn Hospital, Luleå-Boden; Sundsvall Hospital; So¨dersjukhuset, Stockholm; Sa¨ffle Hospital; So¨derta¨lje Hospital; Trelleborg Hospital; Torsby Hospital; Udde-valla Hospital; Umeå University Hospital; Uppsala University Hos-pital; Varberg HosHos-pital; Visby HosHos-pital; Va¨sterås HosHos-pital; Va¨xjo¨ Hospital; Va¨rnamo Hospital; Va¨stervik Hospital; Ystad Hospital; A¨ ngelsholm Hospital; O¨rebro University Hospital; O¨rnsko¨ldsvik Hospital; O¨ stersund
Acknowledgments
The national stroke quality assessment register Riks-Stroke is sup-ported by the Swedish National Board of Health and Welfare, Norrla¨ndska Strokefonden, Vårdalstiftelsen, the Heart and Chest Foundation, King Gustaf V and Queen Victoria Foundations and the Swedish Research Council (projects K2000-27GX-13574-01A and K2000-27P-12314-04B-BS).
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