The economic burden of anxiety and depression




Alan G. WADE, MD, FRCA
CPS Research
Glasgow, UK

The economic burden of anxiety and depression


by A. G. Wade, United Kingdom



Mood and anxiety disorders are chronic illnesses contributing substantially to the burden of illness, and unipolar depression is projected to become the second most common cause of disability worldwide by 2020. The resulting disability has an economic impact on the patient, the health care system and, mainly due to employment issues, society in general. Effective treatments are available, but at significant cost. During a time of limited resources with in most health care systems, it is important that physicians are able to participate fully in any debate about budget allocation. They are only in a position to influence these decisions if they understand how economic evaluations are made. Underdiagnosis of mood and anxiety disorders is a significant problem, particularly for the following three groups of patients: those within the community who simply do not present for care; those presenting in primary care, but complaining of physical symptoms; and those with significant physical illness attending specialist clinics where the concentration of effort will be on the physical disease. More aggressive treatment with the aim of achieving remission rather than merely symptom reduction is needed. Improving compliance with treatment schedules and collaborative management are the most efficient use of current resources to attain improved outcomes for both the patient and society.

Medicographia. 2012;34:300-306 (see French abstract on page 306)



Why should physicians be concerned about economics? Faced with an individual patient, we want to do the best for that person regardless of cost. But we need to look beyond the individual patient and consider the bigger picture. We live in a time of economic constraints, with health care costs increasing faster than general inflation. For many developed countries, demographics indicate that the ratio of elderly people relative to the productive workforce is also increasing, which further compounds the problem.1 It is important to appreciate that demand for medical services can be almost infinite, while resources are definitely finite. The consequence is that treatment options available for an individual patient may be restricted by economic decisions determined by politicians, managers, and others. It is vitally important for the well-being of patients that doctors understand fully the financial implications of medical interventions so that they can influence financial decisions in the best interest of patients.2,3

It is also important that we understand the context within which decisions are being made. On a simplistic level, it is easy to assume that if drug A costs more than drug B to treat the same condition, it is sensible to use drug B. But what if drug A prevents the need for the patient to be admitted to hospital or does not require the time of a nurse to administer the treatment? Hospital costs and nurses salaries may not come out of drug budgets, but should certainly be considered when choosing drug A or drug B. Similarly, from a patient perspective, drug A may get them better quicker, may allow them to continue working during treatment, and may have fewer undesirable side effects. How may these be considered when choosing one drug over another? Even more difficult is comparing across diseases. How does one compare making someone well from acute depression and preventing a myocardial infarction by treating their hypertension for many years? This is the science of medical economics. An inexact science heavily influenced by philosophy and prejudice.4,5


Figure 1
Figure 1. Components of the cost of depression.

Adapted from reference 7: Goodman D. Am J Managed Care. 2000; 6(suppl
2):S26-S30. © 2006-2011, HCPLive Intellisphere, LLC.


Assessing and reporting the costs of medical interventions

Unfortunately, economic evaluations of medical treatment are not simple and are heavily influenced by methodological issues and potential biases which can have an enormous influence on outcomes.6

_ Costs related to illness
In general, there are three sources of cost related to illness. First, there are direct costs of health care. These are probably the simplest to understand, but are not without confounders, and include such items as the costs of hospital admission, diagnostic services, medical time, drugs, and overheads directly related to the health care system.

Second, there are direct nonmedical costs of health care, including provision of special social care services, such as modified accommodation for disability or social support services within the community.

Third, there are indirect costs. These may include lost production due to unemployment, reduced efficiency while at work (presenteeism), early retirement, or premature death. At a time of high unemployment in many countries, this can be a source of considerable discussion. Nevertheless, the economic impact of mental disorders on productivity should not be underestimated. While the absolute figures may now be out of date, more than half the cost of depression in the US in the 1990s was accounted for by absenteeism and presenteeism (Figure 1).7 As the proportion of cost attributed to inpatient care is likely to have fallen, the impact of work-related costs today is likely to be even greater. These figures are reflected in recent estimates of European costs for mood disorders, where over 60% is attributed to indirect costs. By contrast, the indirect cost of anxiety disorders is less than 40%. This suggests that the functional impact of at least some anxiety disorders might be such as to permit continued employment.

As mental disorders are particularly prevalent in the workingage population, the impact on employment and productivity is significantly greater than that of physical diseases, such as diabetes and cardiovascular disorders (Figure 2).8


Figure 2
Figure 2. Mean number of work days lost in the past 30 days for
mental and physical disorders.*

Abbreviation: WLD, work-loss days.
After reference 8: Alonso and Lepine. J Clin Psychiatry. 2007;68(suppl 2):3-9.
© 2007, Physicians Postgraduate Press, Inc.



The costs of other factors, such as medical research, crime in relation to some mental disorders such as addiction, and informal care by relatives and friends might be handled differently in different circumstances.

_ Reporting overall cost of illness
When reporting the overall cost or burden of an illness, there are two basic approaches. The incidence of the disease, ie, the number of new cases in a year, can be taken and costs calculated over the lifetime of the patient. The alternative and more usual approach is to take the prevalence of the illness, ie, the number of patients actually suffering at any one time, and calculate the overall cost for one year.


Figure 3
Figure 3. Comparison of total DALYs and total health expenditure per region.

Abbreviations: CHN, China; DALY, disability-adjusted life-year; EME, Established Market Economies; FSE, Formerly Socialist Economies of Europe; IND, India; LAC,
Latin America and the Caribbean; MEC, Middle Eastern Crescent; OAI, Other Asia and Islands; SSA, Sub-Saharan Africa.
After reference 9: Murray and Lopez. Lancet. 1997;349:1436-1442. © 1997, Elsevier Ltd.



Very often, the costs of individual illnesses are reported on a national, international, or in the case of the World Health Organization, global basis. It is important to remember, however, that economic data produced for one country or one region are not necessarily transferable elsewhere as there are wide discrepancies between the burden of illness and medical expenditure throughout the world (Figure 3).9

By the very nature of these figures, they are extremely rough estimates with “double counting” not uncommon. For example, symptoms of anxiety are frequently present within the syndrome of major depression and vice versa. It is important that the total cost of treatment is not assigned to both disorders. Figures for burden of disease assessments are produced within a political environment, often by experts enthusiastic to ensure maximal funding for research and for patients suffering from diseases in which they have a vested interest.10 This potential conflict of interest is seldom considered.




Comparing the cost burden of different illnesses

If restricted resources are to be equitably assigned, it is important that we are able to compare the value of one medical intervention with another. Is one intervention for treating depression more beneficial than another? What benefit does the patient and society get from replacing an osteoarthritic hip compared with carrying out a coronary angioplasty? In general, this is done by assessing the improvement in the patient’s quality of life and time for which that improvement is enjoyed for each intervention.

Validated scales measuring quality of life fall generally into two categories. Firstly, illness-specific scales, for which the Quality of Life in Depression Scale (QLDS)11 might be considered a good example. This has been specifically developed to assess the impact of changes in the level of depression on the quality of life experienced by the patient. Disease-specific scales tend to be more sensitive to changes in a particular illness and are good for comparing different treatments within that disease area. Generic scales on the other hand, such as Euroqol EQ5D12 and the Short Form (36) Health Survey (SF-36),13 may be less sensitive in recognizing changes in a specific disorder, but have been specifically developed in an attempt to allow comparisons between illnesses.

All illnesses are considered to reduce the quality of life of the patient and medical interventions strive to improve the quality of life. By measuring the improvement of quality of life and the time for which that improvement is maintained, it is possible to obtain a figure. The most commonly used measurement is the quality-adjusted life-year, or QALY.14 One QALY is considered to be one year of perfect health. Depression on average reduces the patient’s quality of life by 50%, and so for each year lived with depression only 0.5 QALY is counted. Treatment of depression has the potential to gain back the lost QALY or at least part of it. The QALY gain can then be assessed against the cost of treatment, and the cost per QALY gained assessed. A patient with rheumatoid arthritis will also have a reduced quality of life for which a cost per QALY gained for treatment can be calculated. Thus, a comparison can be made between the cost of treating a patient with depression and a patient with rheumatoid arthritis. This technique is being more and more widely used by health care providers for assessing whether or not to pay for a particular medical intervention. In the UK, the National Institute for Health and Clinical Excellence (NICE)—the body charged with carrying out these assessments—has a general figure of £20-£30 000 per QALY gained as being cost effective. Despite the apparent objectivity of these measures, there is an ongoing debate at present about the value of different QALYs15,16 with, for example, gains made in increasing life expectancy at the end of life perhaps being considered more valuable than others.

A disability-adjusted life-year (DALY) is the inverse of the QALY, with 1 representing death and 0 representing a full year with no disability.17 An alternative to assessing quality of life is to assess “willingness to pay” for particular health gains. This is usually done at the patient level, and often displays wide discrepancies between apparent quality of life gains as assessed by QALYs and the perceived value to the patient.18

The burden of anxiety and depression

When estimating the cost or burden of anxiety and depression, it is important that we consider not just patients who are treated, but also those who are untreated or inadequately treated. To do this, we need good information about the prevalence of the illness, the proportion of patients receiving treatment, the outcome of treatment, and the cost of failed treatment or nontreatment. Many community-based surveys have been carried out over the last 50 years in an attempt to assess the impact of anxiety and depression, but comparison across studies has been difficult due to the disparity in the methodology.19 It is hoped that the continued development of the WHO Composite International Diagnostic Interview will assist future standardization. The problem of impact assessment, however, is further complicated by the influence that depression, in particular, may have on the adverse outcome of comorbid physical disorders such as diabetes or cardiovascular disease. More recent evidence is tending, certainly for cardiovascular disease,20-22 to suggest a reduced impact of depression on clinical outcomes.23,24

As economic assessments are often made on the basis of single disorders and often with the implicit objective of emphasizing the importance of that disorder, the possibility of “double counting” is always present. For example, insomnia may be a symptom of depression, but may also be considered a comorbid illness. It is important that we do not include the cost of insomnia as both a separate illness and as part of the cost of treating depression. This of course raises the issue of comorbidity between anxiety and depression, which has generally been ignored in economic studies.

Unipolar depression is quoted as being responsible for 8% of all disability in the US, 3.5% in the Eastern Mediterranean, and less than 1% in Africa, the different percentages probably reflecting the success or otherwise in treating other illnesses rather than a difference in the prevalence of depression itself.9 Unipolar depression is projected to become the second most common cause of disability worldwide by 2020, being accountable for 11.6% of the total burden of disease.25 It is interesting that anxiety disorders do not feature within the 10 most common causes of disability. Regardless of the accuracy or otherwise of the data, there is little doubt that depression and anxiety impose a large burden on all societies. And that burden is generally underestimated when one considers the impact on families, close relatives, and work colleagues.

The figures for anxiety tend to be reported on the basis of the individual anxiety disorders, but the most recent European figures26 suggest an overall prevalence of around 10%. This is similar to the figure reported in the ESEMeD 2000 study (European Study of the Epidemiology of Mental Disorders)of 8.4%, of which more than half was attributable to specific phobias.8

Clinicians are aware of the presence of anxiety symptoms in virtually all depressed patients, but true comorbidity, where the symptoms of the second disorder meets the criteria for diagnosis, is particularly common inmood disorder. In the ESEMeD 2000 study, there was a particularly high association between major depressive disorder (MDD) and anxiety disorders (odds ratio [OR], 10.2; 95% confidence interval [CI], 8.2-12.7).8

Managing anxiety and depression efficiently

_ Recognition and diagnosis
There are three distinct groups of patients with depression for which recognition is poor: i) individuals in the community who never report to a health care professional; ii) patients presenting to general practitioners, but not necessarily complaining of symptoms of depression; and iii) patients with physical illnesses such as diabetes or cardiovascular disease, frequently being seen at specialist clinics, but where the focus is very much on the physical problem rather than the patient as a whole.

The nonreporting individuals can only be identified by screening and, in general, there is doubt about the value of this approach. Will the patients identified accept and adhere to treat ment? And even if they do so, will the outcomes match those of patients who seek help? Nevertheless, the US Preventive Services Task Force has recommended screening,27 and while this is widely acknowledged, what is often forgotten is the recommendation that it is only carried out when adequate resources are available for treatment and management. This is reiterated in the review by O’Connor: “Depression screening programs without substantial staff-assisted depression care supports are unlikely to improve depression outcomes.”28

More than 90% of patients with mental health problems are treated in primary care. In the WHO study on Psychological Problems in General Health Care, in 26% of individuals visiting their general practitioner, 17% had some depression and 8.5% had generalized anxiety disorder, of whom 44% had comorbid depression.29 Despite the production of simple screening tools, some as simple as a single question,30 major efforts at educating doctors and their staff, and the production of guidelines, the problem persists. It is unlikely to be solved by any simple individual measure, but by a combination of education of health care professionals and the general public and improved clinical management processes.

The management of chronic physical illness may be adversely impacted by depression comorbidity. This being the case, it should be possible in specialist clinics to specifically screen for depression and make available the resources to manage it.31

_ Efficient treatment
The aim of any treatment should be to achieve remission, not merely symptomimprovement. The presence of residual symptomatology after an episode of depression increases the risk of relapse, a long-term chronic course, higher risks of suicide, poor social functioning, and poor outcome.32,33 The difficulty is to define remission, but from the patient’s perspective it includes the features of positive mental health such as optimism, self-confidence, the return to normal self, and good functioning.34 Regardless of how well the patient is following short-term treatment, it must always be borne in mind that both anxiety and depression are chronic illnesses for which long-term management should be considered.35 The efficacy of antidepressant medication is most clearly demonstrated in the prevention of recurrence or relapse following successful short-term treatment.36 For depression, each recurrence becomes more difficult to treat, and the intervals between episodes become progressively shorter.37

_ Aggressive management based on prediction
The longer a patient persists with symptoms of depression, the more difficult it will be to achieve full recovery. It is logical, therefore, that the sooner patients are treated and the sooner they achieve remission, the better. There is a general perception that antidepressant drugs have a slow onset of effect and that with time improvements will continue to occur. In fact, evidence of improvement can be detected within a few days, and lack of clinical improvement by 14 days predicts a poor outcome.38

It is reasonable clinical practice, therefore, that if improvement is not seen early in the course of treatment, consideration should be given to altering treatment. Similarly, it has been shown that if by eight weeks the patient has failed to achieve response (50% improvement in symptoms), the longer-term outlook is poor and more aggressive management should be considered.39

_ Compliance
Akerblad demonstrated in a two-year follow-up study superior long-term recovery in patients adherent to medication.40 A relationship between medication adherence and reduced short-term disability in an employed population treated with antidepressants has also been demonstrated.41 Nevertheless, as with all chronic diseases, compliance with treatment is a significant problem in both anxiety and depression and may be particularly poor in patients with depression.42

_ Improving outcomes
Simple interventions are unlikely to solve the problem of poor outcomes in depression and anxiety treatment, but improved compliance and improved outcomes may currently be achieved by a combination of initiatives: i) education of doctors and the general public; in general, it has not been possible to show the benefit of education programs,43 but without education it is difficult to imagine that progress will be made; ii) patient participation in decision-making about treatment;44 iii) frequent patient contact, which may not necessarily be face-to-face;45 and iv) improved general management of care involving all members of the medical team.46

We should not underestimate the current success at treating mood and anxiety disorders; even with limited available resources much improved outcomes can be achieved by efficient clinical management. _


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Keywords: anxiety; burden of illness; depression; disability-adjusted life-year; health care cost; quality-adjusted life-year