Depression is the most common psychiatric disorder affecting people aged 65 years and over, yet only a small minority of older people with significant symptoms receive adequate treatment or referral. In this article, Steve Iliffe and Robert Baldwin provide a guide to assist the differential diagnosis of depression and make recommendations for its optimum management.

Population studies have shown that 10-15 per cent of the population aged 65 years or over suffer from significant depressive symptoms¹, making depression the most common psychiatric disorder in later life. Older patients seen in general practice have higher levels of (often unrecognized) depression than do population samples^2-4. Housebound individuals are twice as likely to experience depression than more mobile older people⁵, and those living in sheltered accommodation may have an even higher prevalence of depression (up to 25 per cent)⁶.

GPs are rightly concerned about medicalizing everyday problems, but depressive disorders differ from normal sadness in three important ways:
Duration: symptoms are present for at least 2 weeks
Lack of fluctuation: symptoms occur on most days, most of the time
Intensity: must be of a degree that is definitely not normal for the individual.

Only a small minority of depressed older individuals with significant symptoms receive treatment or referral, even though their GPs frequently recognize their depressed state⁷. The severity of the depression and high levels of anxiety seem to be triggers for referral⁸, but as a whole it seems true to say that depression in later life is under-diagnosed and under-treated. Its significance is under-estimated despite evidence that late-life depression is associated with disproportionately high rates of suicide and high mortality from all causes⁹. Depression is the psychiatric condition most often linked to suicide among older adults¹⁰, and high and rising rates of suicide among older adults-particularly men are a worldwide phenomenon^11,12. Most elderly patients who commit suicide have had recent contact with their GP (approximately one third within the preceding week) and most have major depression^13,14.

Depression in later life is associated with high use of both medical and social services¹⁵ and depressed older people are more likely to be treated for anxiety (or physical symptoms like pain) than with antidepressants or psychological therapies. Depression particularly affects older people who are caring for others.

Diagnosing depression in older patients

Making sense of these depressive symptoms in older people can be difficult. The number of symptoms, and their chronicity, are the two most important clues as to whether depression is 'major' or 'minor', or whether the patient has dysthymia, an adjustment reaction, or a brief depressive reaction. Inevitably this schematic approach over-simplifies a complex problem, so we intend to qualify our arguments in the remainder of this article.

Minor depression

Only a minority of those with depressive symptoms have sufficient symptoms, of sufficient severity, to warrant the diagnosis of major depression, for which antidepressant therapy is most effective. Most older people have fewer depression symptoms and fall into the category of patients suffering from minor depression. This form of depression is characterized by variability of symptoms, by the salience of anxiety, and by somatization, and is also known as:
Demoralization syndrome
Dysphoria
Atypical depression
Masked depression
Sub-syndromal depression¹⁷.

Minor depression is about three times more common in older people than major depression and is the most common type of depression encountered in primary care¹⁸.

Disability and depression

Depression and disability are commonly associated, but most older people with disabilities are not depressed. The association between poor health and depression appears to be greater in people aged 75 years and over, than for younger old people as a whole. Poor health, loss of mobility, and depression are linked with loneliness and social isolation¹⁹. Subjective measures of ill-health like pain or self-rating of health are more strongly related to depression than are more objective measures of illness or disability like the number of chronic diseases or the degree of functional limitation²⁰. Nearly a third of older people with four or more medical problems are depressed, compared with one in 20 of those without a significant illness²¹. Dysthymia, in the sense of a chronic depressive state, is associated with significant physical impairment²². Loss of function appears to have an immediate worsening effect on depressive symptoms, which in turn have a delayed negative effect on functional ability²³.

Detecting depression

Screening instruments may have a role in detecting depression. In older people, the one most widely used is the 15-item Geriatric Depression scale (GDS). A cut-off of greater than 5 gives reasonable sensitivity and specificity results²⁴. It performs satisfactorily in patients with mild to moderate dementia but not severe dementia. The GDS has been translated in many counties and in several different cultures and there is a website with current versions and translations (GDS website: http://stanford.edu/~yesavage/GDS.html).

Appropriate investigations

In those with significant depressive symptoms, the following should be considered: Past psychiatric history
Mental State Examination (including evidence of psychotic symptoms and assessment of cognition by using a relevant screening tool such as the Abbreviated Mental Test Score)
Risk assessment for suicide or harm from self-neglect
Focused physical examination
Physical investigations. Routine tests include full blood count, biochemical profile, B12 and folate estimates and thyroid function
Review of medication and identification of drugs which may trigger/exacerbate depression (for example, some beta-blockers, calcium channel blockers, and steroid medication).

Treatment approaches

A treatment approach to optimize concordance with the therapy requires:
1. Use of medication with low adverse effect profiles
2. Education - specific concerns about medication
3. Inclusion of caregivers in the education and motivational programme where possible and appropriate24 treatment approach.

An approach to deciding on treatment options for the different types of depressive disorder has been proposed²⁵. There is no evidence that one antidepressant is more effective than another. The choice will be determined by:
Severity of depression, with more severe types favouring treatment with tricyclics
Safety: newer antidepressants have a better safety profile on overdose
Prior response to a particular agent
Tolerability
Anticipated side effects
Drug interactions
Compliance.

Psychological treatments such as Cognitive Behaviour Therapy (CBT), Inter-Personal Therapy (IPT), and brief focal analytic psychotherapy as recommended by the National Service Framework for Older People are effective treatments for depressive disorder in older people but are under-used²⁶. Offering support to patients is itself associated with symptomatic recovery²⁷.

The best evidence on continuation and maintenance treatment regimes, as summarized by the Royal College of Psychiatrists, suggests:
That maintenance therapy of 12 months for a first major depressive episode, and longer for a recurrent disorder, would be appropriate, but also that there is less certainty about treatment for non-major depression
That nortriptyline, dosulepin (dothiepin), citalopram and paroxetine can prevent recurrence
And that there is a lack of consensus on how long maintenance treatment should last or whether it should last for life.
Finally, when should specialist advice be sought? When the clinician is unsure about the diagnosis or treatment, especially when psychotic symptoms, self-neglect, or self-harm emerges.

Stephen Iliffe is a Reader in General Practice, Royal Free and University College London Medical School, London, and Robert Baldwin is Consultant Old Age Psychiatrist, Manchester Mental Health and Social Care Trust, York House, Manchester Royal Infirmary

References

1. Sharma VK, Copeland JRM. Presentation and assessment of depression in old age. In: Ghose K. Antidepressants for Elderly People. 1989; Chapman & Hall, London

2. Watts SC, Bhutani GE, Stout IH, et al. Mental health in older recipients of primary care services; is depression the key issue? Identification, treatment and the general practitioner. Int J Geriatric Psychiatry 2002; 17(5): 427-37

3. Olafsdottir M, Marcusson J , Skoog I. Mental disorders among elderly people in primary care: the Linkoping study. Acta Psychiatr Scand 2001; 104(1): 12-18 4. Lyness JM, Caine ED, King DA, Cox C, Yoediono Z. Psychiatric disorders in older primary care patients. J Gen Int Medicine 1999; 14(4): 249-54

5. Bruce ML, McNamara R. Psychiatric status among the home bound elderly - an epidemiologic perspective. JAGS 1992; 40(6): 561-6

6. Field EM, Walker MH, Orrell MW. Social networks and health of older people living in sheltered housing. Aging Mental Health 2002; 6(4): 372-86

7. MacDonald AJD. Do general practitioners miss depression in elderly patients? Br Med J 1986; 292: 1365-7

8. Eustace A, Denihan A, Bruce I, Cunningham C, Coakley D, Lawlor BA. Depression in the community dwelling elderly: do clinical and sociodemographic factors influence referral to psychiatry? Int J Ger Psychiatr 2001; 16(10): 975-9

9. Montano CB. Primary care issues related to the treatment of depression in elderly patients. J Clin Psychiatr 1999; 60: 45-51

10.Conwell Y, Caine ED. Rational suicide and the right to die: Reality and myth. N Eng J Med 1991; 325: 1100-3

11.La Vecchia C, Lucchini F, Levi F. Worldwide trends in suicide mortality, 1955-1989. Acta Psychiatrica Scandinavica 1994; 90: 53-64

12.McIntosh JL. Older adults: The next suicide epidemic? Suicide and Life-Threatening Behavior 1992; 22: 322-32

13.Chiu E, Ames D, Draper B, Snowdon J. Depressive disorders in the elderly: a review. In: Maj M, Sartorius N (Eds). Depressive Disorders. 1999; John Wiley & Sons Ltd, Chichester: 313-63

14. World Psychiatric Association. WPA International Committee for Prevention and Treatment of Depression. Depressive Disorders in Older Persons. 1999; NCM Publishers Inc, NY. (Available on-line: http://www.wpanet.org/sectorial/edu4.html)

15.Beekman ATF, Deeg DJH, BraamAW, Smit JH, Van Tilburg W. Consequences of major and minor depression in later life: a study of disability, well-being and service utilization. Psych Medicine 1997; 27(6): 1397-1409

16.Alexopoulos GS, Katz IR, Reynolds CF, Carpenter D, Docherty JP. The expert consensus guideline series. Pharmacotherapy of Depressive Disorders in Older Patients. Postgrad Med Special Report. 2001; (October):1-86, Expert Knowledge Systems, L.L.C, McGraw-Hill Healthcare Information Programs, Minneapolis, US

17.Gallo JJ, Rabins PV, Iliffe S. The 'research magnificent' in later life: psychiatric epidemiology and the primary health care of older adults. Int J Psychiat in Medicine 1997; 27(3): 185-204

18.Heun R, Papassotiropoulos A, Ptok U. Subthreshold depression and anxiety disorders in the elderly. Eur Psychiatr 2000; 15(3): 173-82

19.Cattan M. Supporting Older People to Overcome Social isolation and Loneliness. 2002; Help the Aged, London

20.Beekman ATF, Kriegsman DMW, Deeg DJH. The association of physical health and depressive symptoms in the older population: age and sex differences. Soc Psychiatr Psychiatr Epidemiol 1995; 30: 32-8

21.Kennedy GL, Kelman HR, Thomas C. The emergence of depressive symptoms in late life: the importance of declining health and increasing disability. J Community Health 1990; 15: 93-104

22.Kirby M, Bruce I, Coakley D, Lawlor BA. Dysthmia among the community-dwelling elderly. Int J Ger Psychiatr 1999; 14(6): 440-45

23.Ormel J, Rijsdijk FV, Sullivan M, van Sonderen E, Kempen GIJM. Temporal and reciprocal relationship between IADL/ADL disability and depressive symptoms in late life. Gerontol 2002; 57(4): 338-47

24.Maidment R, Livingston G, Katona C. 'Just keep taking the tablets': adherence to anti-depressant treatment in older people in primary care. Int J Ger Psychiatr 2002; 17(8): 752-7

25.Baldwin RC, Chiu E, Katona C, Graham N. Guidelines on Depression in Older People: Practising the Evidence. 2002; Martin Dunitz, London

26.Lebowitz BD, Pearson JL, Schneider L, et al. Diagnosis and treatment of depression in late life. JAMA 1997; 278: 1186-90

27. McCusker J, Cole M, Keller E, Bellavance F, Berard A. Effectiveness of treatments of depression in older ambulatory patients. Arch Int Medicine 1998; 158: 705-12

28.Almeida OP, Almeida SA. Short versions of the geriatric depression scale: a study of their validity for the diagnosis of a major depressive episode according to ICD-10 and DSM-IV. Int J Geriatr Psychiatry 1999; 14: 858-65

29.Wilson, K, Mottram, P, Sivanranthan A, Nightingale A. Antidepressant versus placebo for depressed elderly (Cochrane Review). In: 2001; The Cochrane Library, Issue 2. Update Software, Oxford

30.Furukawa TA, McGuire H, Barbui C. Meta-analysis of effects and side effects of lose dosage tricyclic antidepressants in depression: systematic review. Br Med J 2002; 325: 991-5

return to main menu