Family Practice Advance Access originally published online on May 15, 2007
Family Practice 2007 24(3):217-223; doi:10.1093/fampra/cmm009
Associations of depression and anxiety with gender, age, health-related quality of life and symptoms in primary care COPD patients
Department of General Practice and Primary Care, University of Aberdeen, Foresterhill Health Centre, Westburn Road, Aberdeen AB25 2AY, UK
Correspondence to: Dr Jennifer A Cleland; Email: jen.cleland{at}abdn.ac.uk
Received 22 August 2006; Revised 20 December 2006; Accepted 13 March 2007.
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Abstract |
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Background. Under-diagnosis of anxiety and depression in Chronic Obstructive Pulmonary Disease (COPD) patients may have a negative impact on patient quality of life and result in disparity between prevalence and the recognition and treatment of these symptoms.
Objective. To reveal associations of depression and anxiety with demographic, health-related quality of life and clinical characteristics of COPD patients seen in UK primary care.
Methods. Cross-sectional population-based postal survey of COPD patients comprising the EQ-5D visual analogue scale (EQ-5DVAS), the COPD symptom control questionnaire, the Hospital Anxiety and Depression Scale, the Medical Research Council dyspnea index. Demographic and spirometric data were collected from general practice records.
Results. A total of 170 (57%) patients consented to take part. Data are reported on 110 of these patients for whom up-to-date spirometry was available. Approximately one in five participants reported ‘caseness’ for depression (20.8%) and one in three reported anxiety (32.7%). Age and high levels of symptoms were independent predictors of anxiety and depression, as was the EQ-5DVAS of depression.
Conclusions. These data suggest that in UK primary care, depressive and anxious symptoms in COPD are related to age and high levels of symptoms. Depression is also associated with lower patient-reported generic health status. The data suggest that assessment and treatment for depression and anxiety should be considered for all COPD patients, not just those with more severe clinical levels of disease. The potential of the EQ-5DVAS as a screening tool for anxiety and depression in primary care COPD patients also merits study.
Keywords. Age, anxiety, COPD, depression, health status, primary care, symptoms.
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Introduction |
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Chronic Obstructive Pulmonary Disease (COPD) is defined as ‘a disease state characterized by airflow limitation that is not fully reversible’.1 It is a chronic, slowly progressive disorder, usually associated with smoking, which has a major impact on patient's health-related quality of life2 through restriction of activities, loss of independence and decreased social functioning.
The negative impact of COPD can be further complicated by the widespread presence of psychological co-morbidity in COPD patients. Prevalence of depression among patients with COPD is substantially greater than lifetime rates in the general population (ranging from 12% to over 50%3–8 compared to approximately 5%). Similarly, prevalence of anxiety among patients with COPD varies from 10% to more than 50%,9–11 compared with general population lifetime rates of approximately 15%.
The impact of depression and anxiety in COPD is substantial. Both depression and anxiety are significantly associated with decreased functional status and worse health status when compared to those patients without psychological symptoms, even after controlling for the effects of overall health status.12–15 There is an increased risk of rehospitalizations in patients with anxiety.16 In emergency department patients, the presence of anxiety or depression is associated with significantly higher admission and relapse rates.7 Risk of dropout from pulmonary rehabilitation is significantly greater in depressed COPD patients, irrespective of severity of breathlessness.17 More generally, depression limits the impact of smoking cessation programmes.18 Theoretically, anxiety and depression may also influence self-management.11
Recognition and treatment of depression and anxiety in patients with COPD may therefore lead to significant improvements in quality of life, patient self-care and on the effectiveness of therapeutic interventions. However, much of the data on anxiety and depression in COPD come from hospital clinic outpatients or inpatient populations.4,9–14,16,19,20 Little is known about anxiety and depression in primary care populations of COPD patients. What little we do know comes from the Netherlands. van Manen et al.21 identified a prevalence of depression of 21.6% in patients recruited from general practices, with patients with severe COPD at greater risk of depression. More recently, Chavannes et al.22 found that depressive symptoms in primary care COPD patients were related to gender, body mass index and dyspnea.
There have been no studies of the associations between clinical and demographic characteristics, and depression and anxiety in UK primary care patients with COPD. This is of concern given that 85% of all patients with COPD in the UK23 are treated in primary care. The majority of these patients have mild to moderate COPD, do not attend pulmonary clinics and, as a result, have not been studied thoroughly. It is doubtful if data from typical clinical studies of patients with COPD can be extrapolated to the patients met in everyday clinical practice.24 Moreover, a lot of the research on COPD has focused on males. Since COPD is increasing in women,25 female patients must be included in such studies.
Furthermore, how depression and anxiety in COPD are diagnosed is also of importance. A psychiatric interview or even use of standard screening tools which take time for the patient to complete and the practitioner to interpret is unrealistic in busy clinical practice. A method of simple, quick and easily interpretable screening is required if primary care practitioners are to be encouraged to identify and subsequently treat psychological comorbidity in patients with COPD.
The aim of this cross-sectional study was to examine associations of depression and anxiety with demographic, health-related quality of life and clinical characteristics of COPD patients seen in UK primary care.
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Methods |
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Subjects were primary care patients recorded as having COPD registered with three neighbouring practices (summed list size of just under 16 500) in Aberdeen, North East Scotland, in 2004. All patients with a spirometry-confirmed diagnosis of COPD were included, irrespective of level of severity. Spirometry was carried out by practices, as part of their requirements for the New General Medical Services Quality Outcomes Framework.26 Airway obstruction was categorized using the Global Initiative for Chronic Obstructive Lung Disease guidelines.1
Data were collected via a postal questionnaire. One reminder was sent,27 approximately 3 weeks after the initial mailing.
Symptoms of anxiety and depression were measured with the Hospital Anxiety and Depression Scale (HADS).28 The HADS is divided into an anxiety subscale (HADS-A) and a depression subscale (HADS-D) both containing seven items, rated 0–3, giving a possible maximum score for anxiety and depression of 21. A score equal to or greater than 11 indicates probable anxiety or depression (caseness).
Dyspnea was measured by the Medical Research Council (MRC) dyspnea index.29
Health-related quality of life was measured using the EQ-5D visual analogue, or rating, scale (EQ-5DVAS).30 The EQ-5DVAS is designed for self-completion and asks respondents to rate their own quality of life on a thermometer-like 20 cm visual analogue scale from 0 (worst imaginable health state) to 100 (best imaginable health state). The EQ-5DVAS has been shown to be reliable and valid, acceptable and responsive to health changes, in COPD patients.31
COPD symptoms and functional state were measured using the COPD symptom control questionnaire (CCQ).32 This is a reliable, responsive and validated 10-question scale,33 designed for self-completion.
Questions on smoking status, number of years smoked and employment were included in the postal survey. Descriptive data [age, gender, deprivation category (depcat)]34 were identified from practice databases.
Analysis was conducted using the SPSS for Windows package (SPSS for Windows, Rel. 10. 2000, SPSS Inc., Chicago). Groups were compared at baseline for demographic characteristics and scores on the questionnaire measures using the chi-square test, analysis of variance, Kruskal–Wallis and Wilcoxon tests where appropriate, depending on the distribution of the data and whether continuous or categorical. Multiple logistic regression was used to investigate the association of demographic factors on HADS caseness and to explore the independent relationships between measures. Age and practice were forced into the models and then a forward stepwise procedure was employed.
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Results |
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A total of 357 COPD patients, from a summed practice size of just under 16 500 (approximately 2.2%) were identified from read codes, and sent a questionnaire pack; 255 (71.4%) replies were received, 205 of which were usable. The majority of non-usable questionnaires were returned by patients who stated that they did not wish to take part in the survey. This represented an overall usable rate of 57%, similar to other primary care surveys of patients with respiratory disease.35 Of the 205 usable responses, 170 patients consented to take part in the study (47.6% of those originally mailed a questionnaire pack).
Between non-responders and responders, there was no significant difference in age [mean age 68.59 (11.79) and 67.80 (SD 10.59) years, respectively; P = 0.54] or depcat (median depcat for each group was 3; P = 0.90). However, significantly more women responded than men (P = 0.02).
There was no significant difference in age between those who responded stating that they did not consent to take part, compared to those who consented [mean age 70.39 (10.41) and 66.76 (SD 9.60) years, respectively; P = 0.09]. Consenting patients ranged in age from 42 to 89 years. There was no significant difference in gender (P = 0.08) or depcat (P = 0.59) between consenting and non-consenting patients (P = 0.08). Note that depcat 6 and 7 were not represented in the study population.
Up-to-date spirometry was only available for 110 of the 170 consenting patients, giving an effective response rate of 31%. The main reason for this was that the remaining 60 patients had not recently (i.e. in the last 2 years) attended their GP or Practice Nurse for a COPD review. However, analysis revealed that these 60 patients did not differ significantly in terms of age (P = 0.587), sex (P = 0.521), HADS anxiety score (P = 0.355) or HADS depression score (P = 0.914) from the 110 subjects who did have up-to-date spirometry data. Thus, there were no significant differences on our range of measures across the 110 patients whose results are reported and the 60 patients who were excluded from subsequent analyses on the basis of no recent spirometry.
From this point forward, data are reported only for the 110 patients. Table 1 shows the patient characteristics of these 110 consenting patients for whom spirometry was available.
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Most people were retired (61.2%), used to smoke but had quit (50.0%) and, among those who had smoked, they had smoked for a median of 40 years [inter-quartile range (IQR) 30–47.8]. Just over half of these patients had a spirometry-based diagnosis of moderate COPD (56.4%) and reported breathless at MRC grade 2 or 3 (shortness of breath when hurrying or walking up a slight hill or slower than contemporaries on level ground/stopping for breath). Their median CCQ total scores fell below 3, indicating overall low levels of symptoms. Median HADS anxiety and depression scores were well below the level normally denoting caseness. The median ED-5DVAS score was 60 (IQR 40–70).
Table 2 shows that approximately one in five (20.8%) participants reported probable clinically significant depression. Similarly, around one in three participants under the age of 60 years, and one in six aged 60 years and over, reported scores that indicated probably clinically significant levels of depression, as did 42.4% of patients who scored under 50 on the EQ-5DVAS and just over 40% of COPD patients with a CCQ score of 3 or more.
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Table 3 shows that approximately one in three (32.7%) participants reported probable clinically significant anxiety: this also differed by age with respondents under 60 years of age more likely to report this than those of 60 years and over (46% compared to approximately 28%, respectively). Over 50% of those who scored under 50 on the EQ-5DVAS reported probable clinically significant anxiety compared with less than 20% of participants who scored over 50 on the EQ-5DVAS (P < 0.001). Similarly, almost 60% of those with a CCQ score of equal or greater than 3 reported significant anxiety. However, note that the numbers were small in some of the subgroups in Tables 2 and 3 due to incomplete questionnaires.
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Table 4 illustrates a positive correlation between scores on the CCQ and the HADS anxiety and depression scores. Patients with high CCQ scores tended to have high anxiety and depression scores (P < 0.001). Table 4 also shows a negative relationship between patients' scores on the CCQ and the EQ-5DVAS: patients with a high CCQ score tended to have a low score on the EQ-5DVAS (P < 0.001).
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Table 5 illustrates that, following adjustment for sex and practice, significant independent predictors of both HADS anxiety and HADS depression were age group and CCQ score. EQ-5DVAS was also a significant independent predictor of HADS depression.
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Subjects aged over 60 years were significantly less likely to be anxious or depressed than younger subjects. Patients with a total score of 3 and above on the CCQ (i.e. higher levels of symptoms) were almost 20 times more likely to be clinically anxious, and almost 10 times more likely to be clinically depressed than patients with a total score of 2 or less. Those who rated their health-related quality of life as less than 50 on the EQ-5DVAS (poor) were almost six times more likely to be depressed than those who rated it above 50.
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Discussion |
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This study aimed to identify potential associations between demographic factors, clinical characteristics and psychological morbidity in a primary care population of COPD patients. The prevalence of depression (approximately 20%) was similar to that reported by van Manen et al.6 in their general practice population. Anxiety levels were higher (approximately 30%), again similar to previous studies (of hospital outpatients).12,14 These high rates stress the importance of screening and treatment of depression and anxiety in patients with COPD to maintain health and functional status,12–15 prevent unnecessary hospitalizations,16 admissions,7 dropout from pulmonary rehabilitation17 or poor outcomes from smoking cessation programmes.18
Of importance was our finding that anxiety and depression differed by age group: clinically significant levels of depression and anxiety were more prevalent in patients aged less than 60 years, irrespective of clinical severity of COPD. This is of relevance for practice: GPs need to be aware that anxiety and depression are more common in younger COPD patients.
The apparent decrease in depression and anxiety with advancing age could be due to a number of factors. Older people anticipate illness as a predictable late-life stressor36 as part of growing old. Thus, health-related stressors may not produce the same reactions in the elderly although their impact can be just as devastating. Although the older respondents may have difficulties, they may see themselves as on par with others of their age. In contrast, it is uncommon to be physically disabled and functionally limited preretirement. Thus, younger patients may find it difficult to come to terms with enforced changes in lifestyle, with this leading to psychological morbidity.
Our data indicated that the perceived severity of COPD symptoms, assessed by patients' responses on the CCQ, but not the MRC index, was predictive of depression and anxiety in our patient population. Patients with higher scores (3 and over) were approximately 10 times more likely to have probable clinically significant depression and 19 times more likely to have probable clinically significant anxiety than those with total CCQ scores of 2 or less. This supports previous findings.6 Symptoms may contribute to the ability to cope with living with COPD and hence the development of mood disorders.
Unlike Chavannes et al.,22 we did not find that gender was significantly predictive of depression caseness. This is likely due to differences in study design, the use of different measures and different study populations, and perhaps timing of data collection. It would be of interest to investigate associations of depressive and anxious symptoms in COPD during a set time period to compare populations throughout a random selection of UK and Dutch general practices.
Scores on the EQ-5DVAS were significantly predictive of depression but not anxiety. While further research is required, in routine practice, it may be that the brief, simple and quick EQ-5DVAS is a useful tool for GPs to screen a patient's mental health status. Low scores on the EQ-5DVAS suggest the need to enquire further about depression. More studies are required to explore the utility of the EQ-5DVAS in identifying anxiety in COPD.
We found a strong negative correlation between respiratory symptoms (CCQ) and EQ-5DVAS scores. This suggests thatthe EQ-5DVAS may be a useful measurement of broad (i.e. not solely respiratory) health-related quality of life in patients with COPD.
A possible criticism of this study is that we did not measure functional status in our population and thus were unable to examine the relationships between that and psychological health, health-related quality of life and symptoms.
The selection of the study population was based on registration with three particular general practices and it is possible that this led to some selection bias. However, this is a relevant setting for a survey, on a representative population given that primary care plays a major role in the early detection, preventative management and treatment of COPD. In addition, we included practice as a confounder in all the multiple logistic models. Some might regard the small sample size as a potential limitation and may criticise our use of multivariate modelling. However, given the reasonably high prevalence of anxiety and depression in our study, we deemed it appropriate to show both unadjusted and adjusted odds ratios allowing the reader to judge how much emphasis to place on the stepwise models. Although the main analyses was performed on an effective 31% response rate, analyses revealed that the subset of 110 subjects with up-to-date spirometry were representative of the consenting group since their age, sex, HADS anxiety and HADS depression scores did not significantly differ from the 60 patients who consented but did not have current spirometry data.
Doctors are more likely to identify depression if they believe in the effectiveness of treatment and feel confident in their ability to treat the condition.37 There is some evidence that depression and anxiety in COPD can be treated with pharmacological therapy.38 There is also evidence that even a single session of cognitive behaviour therapy plus telephone follow-up may improve mental health status for patients with COPD also.39
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Conclusions |
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These data suggest that in UK primary care, depressive and anxious symptoms in COPD are related to age and the presence of high levels of symptoms. Depression also seems to be associated with lower patient-reported generic health status. Based on our findings and previous reports in the literature, we hypothesize that younger patients with COPD may cope less effectively and this deserves further research. Furthermore, the data suggest that diagnosis and treatment for depression and anxiety should be considered for all COPD patients, not just those with more severe clinical levels of disease. The potential of the EQ-5DVAS as a screening tool for anxiety and depression in primary care COPD patients also merits study.
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Declaration |
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Funding: This study was funded jointly by Aberdeen City Collective, Grampian Primary Care Trust and by an unconditional educational grant from Glaxo Smith Kline.
Ethical approval: Ethical approval for this study was obtained from Grampian Research Ethics Committee.
Conflicts of interest: None. JAC and AJL have received unconditional sponsorship for travel and research from pharmacological companies.
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Acknowledgments |
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We wish to thank the staff and patients of Elmbank, Mary Esselmont and Westburn Practices, Aberdeen, for their help and support with this survey.
Contributors: JAC developed the study design, supervised the study progress and prepared the manuscript. AJL planned and supervised the statistical analysis and reviewed the manuscript. SH organized and analysed the data and wrote the first draft of the results.
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Notes |
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Cleland JA, Lee AJ, Hall S. Associations of depression and anxiety with gender, age, health-related quality of life and symptoms in primary care COPD patients. Family Practice 2007; 24: 217–223.
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References |
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