2006 overview: Key learning points in old age psychiatry

Key learning point 1

Reduced Heart Rate Variability is Linked to Cardiac Death in the Depressed Elderly

It is well established in the literature that untreated depression more than doubles cardiac mortality in older people. A possible mechanism for this is via reduced heart rate variability (HRV), which is readily measured from a resting ECG. HRV represents a balance between vagal tone and sympathetic nervous system activity – the latter is increased in depression, resulting in reduced HRV. Reduced HRV is unequivocally linked to cardiac mortality in health adults.

A Dutch study published in March 2006 in the International Journal of Geriatric Psychiatry (ref. 1) investigated this link in a primary care population. Of 6,719 over 55s in 14 family practices, 187 were found to have untreated Major Depressive Disorder. These subjects had reduced HRV compared to (non-depressed) controls, after adjusting for age, sex, smoking, diabetes, and cardiac medication.

This cross-sectional study could not establish a direction of causality; longitudinal studies of similar rigour are required. However, the Key Learning Points are that untreated depression kills older people; and that primary and secondary care physicians need to pay particular attention to treating cardiovascular risk factors in older people with depression, alongside the treatment of depression.

Key learning point 2

Care Management in Dementia Works

Untreated dementia leads to poor outcome, stress and morbidity for carers, and high resource utilisation. Co-ordinated assistance from multiple health and social care resources may reduce this burden and improve outcomes, and is proposed in the recently published UK National Institute for Health and Clinical Excellence Guidelines on Dementia. But what is the evidence that it works? Previous studies in the UK have focussed on nurse-led Admiral Nursing projects, which have shown promise in helping to co-ordinate care in dementia. Now a randomized controlled trial has been published in America, suggesting a clear advantage of care management on quality and outcomes of dementia care.

Vickrey et al. (ref. 2) randomized 238 patient-caregiver pairs to a disease management programme, or care as usual. The care managers, usually social workers trained carers, did assessments, and co-ordinated care in 3 health care organisations collaborating with 3 community agencies in California. Over-65 patients with dementia and their carers were drawn from 18 primary care clinics.

Participants who received the intervention had higher care quality on 21 of 23 parameters, and higher proportions received community agency assistance than those who received usual care. Patient health-related quality of life, overall quality of care, caregiving quality and social support were better for participants than for the control group who received usual care, though caregiver health-related quality of life did not differ between the two groups.

Although this study was on a predominantly white middle class population, it provides convincing evidence that care management/case management works in dementia. In the USA, the challenge is that the reimbursement system is not designed for complex, intensive multi-agency treatments. In Europe, the challenge is that there are nowhere near enough case managers, nor community based resources, to provide effective case management for the numbers of people with dementia.  This study should nudge commissioners towards providing these resources.

Key learning point 3

Antidepressants Stop Depression Recurring in Older People; Psychotherapy does not

Relapse is common in older people recovering from depression, both in first episode and recurrent depression. The literature is scarce in this area, as large scale studies are difficult and expensive to perform.  An important study in this area was published in the New England Journal of Medicine in March 2006 (ref. 3).

The study, independent of the pharmaceutical industry, followed up 116 over 70s for 2 years who were recovering well from major depression after 4 months combined treatment with paroxitene and interpersonal therapy. 55 % had been depressed only once. The headline finding was that serious depression recurred in 35% of paroxitene and psychotherapy group, 37% of paroxitene plus monthly chat about symptoms group, but 68% of those who had psychotherapy plus placebo.

This study is an important contribution to the literature, but leaves many research questions unanswered. Is there a subgroup of patients who would benefit from psychotherapy? Is interpersonal therapy (not cognitive behavioural therapy) the right psychotherapy modality to use? Does vascular depression in first episode patients impair ability to benefit from psychotherapy?

Whatever the answers to these important questions, the Key Learning Point is that paroxitene is cheap and effective at preventing relapse. The authors calculated that only 4 people would need maintenance treatment with paroxitene to prevent 1 recurrence of depression.

Key learning point 4

Caregiver Characteristics are Associated with Behavioural and Psychiatric Symptoms in Dementia (BPSD)

BPSD is common in dementia, and frequently leads to institutionalisation and poor outcome. A study published in the Journal of the American Geriatric Society in May 2006 (ref. 4) sought to establish the link between caregiver characteristics and BPSD in nearly 6,000 dementia patients. There is an extensive literature linking high expressed emotion (EE) in schizophrenia carers to poor outcome, but surprisingly little research in the dementia field.

The authors found that caregivers who were younger, less educated, more burdened, or depressed, reported significantly more BPSD. Caregiver characteristics accounted for twice the variance in BPSD compared to patient characteristics.

If BPSD is partly determined by caregiver personality and stress (as in EE with schizophrenia), this lays the foundation for caregiver interventions. The key learning point is that improving caregiver educational and psychological health, may reduce BPSD – and hence, improve outcome – in the dementia patient.

Key learning point 5

Silent Cerebral Emboli are Frequently Occuring in Alzheimer's Disease (AD) and Causing further Brain Damage

Two important studies have been published in the British Medical Journal and the British Journal of Psychiatry in late 2006 (ref. 5). 142 patients with AD and vascular dementia (VaD) were recruited from secondary care Old Age Psychiatry Services in Manchester: patients on Warfarin were excluded. Using sophisticated scanning technology, they identified cerebral microemboli occurring during a 1 hour period in 40% of patients with both AD and VaD. 

The data was analysed in the second study to find a link between those exhibiting microemboli and depressive symptoms: a score of >4 on the depressive subscale of the Neuropsychiatric Inventory.

The Key Learning Points are firstly that microemboli may be occurring more frequently than realised in patients with dementia – and contributing to brain damage and progression of dementia. Secondly, microemboli may be contributing to depression in dementia, particularly if fronto-striatal pathways accrue embolic damage. To move into the realms of speculation, this lends weight to the vascular depression hypothesis for first episode depression in late life, and may lead to anti-embolic treatment as prevention and treatment of depression in dementia.

References

1. van der Kooy KG, van Hout HP, van Marwijk HW, de Haan M, Stehouwer CD, Beekman AT. Differences in heart rate variability between depressed and non-depressed elderly. International Journal of Geriatric Psychiatry 2006; 21 (2); 147-150

2. Vickrey BG, Mittman BS, Connor KI, Pearson ML, Della Penna RD, Ganiats TG, et al. The effect of a disease management intervention on quality and outcomes of dementia care: a randomized, controlled trial. Annals of Internal Medicine 2006; 145 (10); 713-726

3. Reynolds CF 3rd, Dew MA, Pollock BG, Mulsant BH, Frank E, Miller MD, et al. Maintenance treatment of major depression in old age. New England Journal of Medicine 2006; 354 (11); 1130-1138

4. Sink KM, Covinsky KE, Barnes DE, Newcomer RJ, Yaffe K. Caregiver characteristics are associated with neuropsychiatric symptoms of dementia. Journal of the American Geriatrics Society 2006; 54 (5); 796-803

5. Purandare N, Voshaar RC, Hardicre J, Byrne J, McCollum C, Burns A. Cerebral emboli and depressive symptoms in dementia. British Journal of Psychiatry 2006; 189; 260-263