Age Changes
- Brain weight decreases by 20% from its young adult weight by the age of 90.
- Selective neuronal loss of 5–50%, and cells tend to shrink.
- Fifteen to twenty percent reduction in synapses in the frontal lobes.
- Lipofuscin accumulates in some cells (significance uncertain).
- Plaques and tangles are found in aged brains, but seldom in middle-aged ones.
- Granulovacuolar degeneration can often be found in the hippocampus and occasional vascular amyloid deposits are seen in cortical blood vessels.
- All these changes are more pronounced in Alzheimer’s disease (AD), but AD is not just exaggerated ageing.
- Performance in intelligence testing, learning ability, short-term memory and reaction time tend to decline with age (see age-associated memory impairment, p. 53) but often not significantly until about the age of 75.
Sleep
Sixty percent of older people complain about insomnia; sleep quality worsens with ageing. Studies indicate that the overall duration of sleep is the same, but sleep is more disturbed with more arousals. Periods of rapid eye movement sleep change little but there is less slow-wave sleep. Apnoeic episodes are more common. The worst sleep patterns are found in patients with dementia.
Factors that Disturb Sleep Patterns
- Anxiety.
- Depression.
- Pain.
- Discomfort due to constipation.
- Urgency, frequency, nocturia.
- Restless legs (pramipexole and ropinirole are licensed treatments).
- Cramps.
- Nocturnal cough or breathlessness.
- Drugs (theophylline, sympathomimetics, high dose steroids; alcohol initially sedates but alerts later).
- Drug withdrawal (sedatives, hypnotics).
If simple corrective measures do not help, look for and treat any factors listed in the above list. Avoid hypnotics if possible as elderly persons are more likely to fall, e.g. if they have to get up to go to the toilet, and there may be a hangover effect the next day. If the situation is causing distress to the patient or carer, a short course of a hypnotic may be justified. Melatonin, the pineal hormone involved in circadian rhythms, is licensed for insomnia, but evidence that this is preferable to hypnotics is scant.
Obstructive sleep apnoea/hyponoea syndrome (OSAHS) increases with age; the jaw tends to shorten especially if edentulous and the airways tend to be narrower and less well supported as muscles and connective tissues age and become fatty. Extreme daytime sleepiness with poor concentration and reports of night-time ‘choking’ or extreme snoring should trigger referral for a sleep study. Continuous positive airways pressure (CPAP) with a modern mask is well tolerated, improves sleep, mood and cognition and reduces the associated high blood pressure.
REM sleep behavioural disorder is more common in old age, often associated with neurological disease, and is characterized by purposeful sometimes violent movements reflecting dream activity. It responds to low dose clonazepam or melatonin.
Problem Drinking
Older people are less tolerant of alcohol due to:
- a lower ratio of body fat to water;
- a lower hepatic blood flow and reduced metabolism;
- increased brain sensitivity.
At any age, repeated excessive ingestion leads to dependency, physical disease or harm. Consumption peaks at age 55 and declines thereafter, but this may change as the middle aged who are used to drinking more than earlier generations grow old. Older people may benefit from low to moderate alcohol intake, for example cardiovascular benefits and improved quality of life. However, the Royal College of Psychiatrists (2008) estimates that 1 in 6 older men and 1 in 15 older women are drinking enough to harm themselves.
There are three patterns of drinking, described below.
Early-Onset Drinkers or Survivors
- Males = Females, i.e. there is no gender preponderance.
- Two-thirds of elderly drinkers have a continuing alcohol problem that began when younger.
- Likely to be resistant to help.
Late-Onset Drinkers or Reactors
- F > M.
- Use alcohol in an attempt to assuage loneliness and sadness.
- Depression common.
Intermittent or Binge Drinkers
- A less common pattern.
Problems Linked to Alcohol
- Falls, with increased risk of osteoporosis and therefore fractures, accidents, bruising.
- Self-neglect.
- Acute confusion, anxiety, depression, neuropathy, hallucinations, Wernicke’s encephalopathy, dementia, fits.
- Gastrointestinal and liver disease.
- Heart problems including cardiomyopathy and atrial fibrillation.
- Haemorrhagic stroke.
- Bone marrow suppression.
- Many cancers.
- Hypothermia.
- Interaction with medications.
The usual problem is daily dosing rather than bingeing, so the alcohol problem may not be apparent. Consider a simple screening tool like CAGE (see Appendix 3), but this may be less valid in older drinkers.
Treatment entails total withdrawal: delirium tremens is managed with chlordiazepoxide (use lower doses). In problem drinking, it may be possible to reduce intake: check who is buying the alcohol. The Institute of Alcohol Studies produces a useful fact sheet, and Alcoholics Anonymous (AA) offers helpful support for those who find their methods acceptable.
Anxiety
Anxiety is very common in older people. It may accompany depression, dementia and physical illness or may cause physical symptoms (palpitations, breathlessness, giddiness, abdominal discomfort, bowel fixation). Always consider anxiety or depression in recurrent attenders and in rehabilitation patients who fail to make progress. When severe (Generalized Anxiety Disorder) it decreases social functioning and has a marked impact on health-related quality of life. Treatments include reassurance or cognitive therapy, but if associated with panic attacks, try duloxetine (a serotonin and noradrenaline reuptake inhibitor, SNRI), escitalopram (a selective serotonin reuptake inhibitor, SSRI), or pregabalin (antiepileptic GABA agonist).
Late-Onset Delusional Disorder
This is a schizophreniform paranoid psychosis in which personality, affect and self-care skills are well preserved and there is no thought disorder. It most often affects single women who live alone, especially those who suffer from deafness. Isolation is thought to be a significant factor in its development. There is often a highly structured system of delusions and hallucinations, which may centre on a conspiracy involving the neighbours or have a sexual content. The response to antipsychotic drugs is good if concordance can be achieved. Newer agents, such as low-dose risperidone, were thought to cause fewer long-term side-effects but were more expensive. However, now they are cheaper, but it is recognized that they have a range of serious side-effects.
Causes of Hallucinations
- Bereavement.
- Depression.
- Acute brain syndrome (including drugs, e.g. dopaminergic treatment for PD).
- Dementia.
- Late onset schizophrenia.
- Poor vision (Charles Bonnet syndrome – no other features of psychiatric illness – patients need explanation and reassurance that this is not a harbinger of mental illness).
Depression
Prevalence
Depression occurs in around 10–15% of people aged over 65 years and is severe in 3%. Unipolar depression is most common, but bipolar disorders make up 5–10% of more severe cases and the hypomanic phase is often missed. The key is to consider the possibility of a mood disorder. Ask the patient – most will tell you and there is a surprisingly good correlation between a Yes/No answer to the question ‘Are you depressed?’ and the result of a full psychiatric assessment. Screening tools such as the Geriatric Depression Score (see Appendix 5) may be helpful. Many old, ill people in hospital are anxious, lose their appetite and cannot sleep or concentrate. In the list of features that follows, physical aspects are least helpful in discriminating between physical and psychiatric disease and anhedonia perhaps the most.
Features
- Association with physical illness especially chronic disease. Growing evidence for a subtype of depression in later life associated with cerebrovascular disease.
- Somatization of symptoms, hypochondriasis.
- Pervasive anhedonia (‘when did you last enjoy anything?’).
- Guilt, worthlessness, low self-esteem.
- Hopelessness and helplessness.
- Apathy or agitation, anxiety, delusions.
- Sleep disturbance.
- Withdrawal, poor concentration and memory (‘pseudodementia’).
- Self-neglect, malnutrition, dehydration.
- Suicide risk.
In almost all industrialized countries, men aged 75 years and older used to have the highest suicide rates. Suicide attempts in older people are often long planned, involve high-lethality methods and, as the elderly are more fragile and frequently live alone, often lead to fatal outcome. In later life, in both sexes, major depression is the most common diagnosis in those who attempt or complete suicide. In the UK, the greatest reductions in male suicide rates have been seen in men over 75 years, from 25 per 100,000 population in 1991 to 14 per 100,000 population in 2009 (n = 262). The trend in older women is similar but with rates of about one-third. This is strong evidence that recognition and treatment of depression in old age has improved (Figure 4.1). However, a previous serious attempt, bereavement and isolation all point to high risk.
Management
Supportive
- Mild depression is managed in primary care.
- Counselling.
- Relieving loneliness.
- Practical measures, e.g. benefits check.
- More severe depression is often best managed with help of the local Old Age Psychiatry service, involving community psychiatric nurses (CPNs), social workers and a consultant. The team usually assesses the patient in their own home and will support them to continue with medication or cognitive behavioural therapy.
- Old Age Psychiatry service may offer day hospital care, which might include exercise, cognitive behavioural therapy (CBT) and art therapy, with different days for clients with depression or psychosis and dementia.
- Referral to Cruse Bereavement Care if relevant.
- Remember to support the carers; depression is extremely common and it is essential to offer support, e.g. respite care or a sitting service such as Crossroads for the patient, before deterioration in the carer’s mental health precipitates a crisis.
Drugs
- SSRIs are the drugs of choice, because of fewer sedating and anticholinergic effects than the tricyclic antidepressants. Watch for hyponatraemia.
- They are relatively safe in overdose.
- Nausea, diarrhoea and restlessness can occur.
- To minimize nausea, start at a very low dose for the first week and increase gradually. Explain to the patient that any nausea will wear off.
- Give a simple explanation of the chemical basis of depression and explain that depression cannot just be shaken off by ‘counting your blessings’ or having a bit more moral fibre!
- Explain to patients that SSRIs are different from benzodiazepines, do not usually cause dopiness, and will be stopped gradually when no longer needed.
- Strongly reinforce the need to stick with the tablets for at least 6 weeks before expecting the cloud to lift. Information sheets can be useful. Treatment should be continued for a year, or possibly even for life in severe cases.
- Our current practice is:
Citalopram (SSRI) starting with 10 mg for most patients.
Mirtazapine (a presynaptic α2-antagonist, which increases noradrenergic and serotinergic transmission) stimulates appetite and aids sleep.
Trazodone (tricyclic with few antimuscarinic effects) if sedation is needed.
Venlafaxine (SNRI) for resistant depression.
- Lithium is helpful as a mood stabilizer in bipolar disorder, but it has a narrow therapeutic index and levels must be checked if toxicity is suspected (tremor, ataxia, impaired renal function).
- Fluoxetine, fluvoxamine and paroxetine (all SSRIs) are more likely to be involved in significant drug–drug interactions than citalopram or sertraline.
- If SSRIs cause nausea and the patient is sleepy try lofepramine (a tricyclic with few antimuscarinic side-effects), building up from 70 mg.
Electroconvulsive Therapy
Electroconvulsive therapy (ECT) is comparatively quick, safe and effective in severe depression, but most psychiatrists are now very reluctant to consider ECT because of the bad press it has received. The Mental Health Act 2007 states that ECT may not be given to a patient with capacity who refuses it, and may only be given to an incapacitated patient where it does not conflict with any advance directive, the decision of a donee (the person who is given the power of attorney) or deputy, or the decision of the Court of Protection.
Acute and Chronic Confusion
Many old people are described as confused. Anyone can become delirious when they are ill, but this is common in frail older people. Simplistically, delirium is the term used for acute confusion and dementia describes chronic confusion. The interrelationship between the two is complex.
- Dementia is the biggest risk factor for delirium; a person with dementia typically gets much more muddled when ill and improves to some extent (but not always back to baseline) if they recover.
- Delirium may persist for months (or years according to some) – when does this become ‘dementia’?
- Some causes of dementia are reversible.
- Long-term cognitive decline is common after an episode of delirium.
- Dementia with Lewy bodies (see later) has features more typical of delirium.
Delirium
Delirium is a transient, reversible syndrome that is acute and fluctuating, and occurs in the setting of a medical condition. Delirium is common and occurs in up to half of frail older patients admitted to hospital. It can be a key component in the cascade of events leading to a downward spiral of functional decline, institutionalization and eventually death.
Susceptibility Factors
- Age.
- Cognitive impairment.
- Previous episode of delirium.
- Depression.
- Multiple comorbidities.
- Multiple drugs.
- Falls (a marker of frailty).
- Sensory impairment.
Precipitating Factors
Intracranial
- Infarction – any stroke, especially right parietal and most confusing for the doctor if no physical signs; often frontal.
- Infection – meningoencephalitis.
- Injury – head injury with contusion or intracranial blood, fat embolism.
- Post-ictal – (if the fit is missed the patient is just found on the floor).
- Iatrogenic – drugs acting on the CNS (including abrupt withdrawal, e.g. benzodiazepines not charted).
Extracranial
- Infection – commonly chest, urine and cellulitis.
- Metabolic and nutritional – fluid and electrolyte imbalance, hypoglycaemia, hypo-/hyperthermia, refeeding syndrome, Wernicke’s encephalopathy.
- Anoxia – cardiac or respiratory failure, ‘silent’ myocardial infarction, anaemia.
- Toxic – drugs and alcohol.
- Stress response.
- Anaesthesia and surgery.
Consequences of Illness and Hospitalization
- Pain.
- Emotional distress.
- Sleep deprivation.
- Unfamiliar environment exacerbated by loss of glasses, hearing aids.
- Catheters, drips, etc.
- Urinary retention, constipation.
The pathophysiology is poorly understood (see Figure 4.2); susceptibility factors all impair neurotransmission. The precipitating events cause further acute breakdown of network connectivity, by increasing inhibitory tone within the brain (GABAergic neurotransmission). All transmitters may be affected, but a frequent pattern is cholinergic hypofunction and dopaminergic excess. The form of delirium that results, hypoactive, hyperactive or mixed, depends on which networks are affected. A small study with single-photon emission computerized tomography (SPECT) has shown hypoperfusion in the frontal, parietal and pontine regions.
Clinical Features of Delirium (Acute Confusion)
- Onset typically rapid over hours to days.
- Marked fluctuation: lucid intervals.
- Reversal of sleep–wake cycle is common.
- Altered consciousness often described as ‘clouding’.
- Inability to sustain, focus or shift attention.
- Disturbed cognition, e.g. disorganized thinking, disorientation.
- Illusions, misinterpretation, e.g. thinking an IV line is a snake.
- Hallucinations, perception in the absence of a stimulus.
- Delusions, false beliefs; the patient may deny they are ill and escape from the hospital.
- Fear, bewilderment, restlessness or hypoactivity.
- Possibly signs of underlying cause.
Management
- Prevention: attention to orientation, food and fluids, sleep and sensory inattention has been shown to reduce the incidence of delirium. Avoid suddenly stopping sedatives and antidepressants unless essential, and use caution with new drugs that cross the blood–brain barrier.
- Identification of high-risk patients and educating the family reduces distress.
- Recognition of delirium is the key. An algorithm such as the CAM (see box) may help. Agitated delirium is obvious, but apathetic delirium with withdrawal and drowsiness is easy to overlook.
- Treat underlying cause/s.
- Look for exacerbating factors, e.g. faecal impaction, urinary retention, pain.
- Correct additional factors: fluid and electrolyte imbalance, nutritional deficiencies.
- Reassurance and explanation: avoid confrontation; ask the family to sit with patient.
- Optimize environment and sensory input: glasses, hearing aid, quiet familiar music, dim light at night, but avoid overstimulation.
- Minimize moves around the hospital and ward.
- Avoid complications: nurse sitting with the patient, 1 to 1 ‘specialling’, mattress on floor to reduce risk of hip fracture, pressure mattress.
- Serious restlessness or agitation not responding to above measures: haloperidol or risperidone, start with 0.5 mg, increasing if necessary in increments after 2 h; if neuroleptics are to be avoided (concern about DLB – see later) try lorazepam. Give drugs orally if possible (will take 30–60 min to start to have effect) or IM if essential to sedate rapidly for the person’s safety.
Dementia
Dementia is a clinical and public health problem of enormous magnitude.
What is Dementia?
Dementia is a syndrome (lots of causes) of acquired (not learning difficulties), chronic (lasts months to years), global (not just memory or just language problems) impairment of higher brain function, in an alert patient (not drowsy), which interferes with the ability to cope with daily living (it does not usually matter if an old person does not know ‘it’s Tuesday’, but if he or she does not know ‘it’s winter’, he or she might freeze).
Remember:
| My | memory – short-term memory loss predominates in early dementia |
| Old | orientation |
| Grandmother | grasp and other executive functions such as planning |
| Converses | communication |
| Pretty | personality change |
| Badly | behavioural changes including dyspraxia – difficulty with complex motor tasks, e.g. dressing oneself and agnosia – problems recognizing people and objects, leading to a variety of behaviour that is difficult to manage. |
| After Brice Pitt (Emeritus Professor of Old Age Psychiatry at St Mary’s, London) | |
Causes of the Dementia Syndrome
Primary dementias, where the disease mainly affects the neurons in the brain, are categorized as:
- Alzheimer’s disease (AD), the commonest cause.
- Dementia with Lewy bodies (DLB).
- Frontotemporal lobar dementias (FTD).
Rarer causes are:
- Prion diseases such as familial, sporadic and variant Creutzfeldt–Jakob disease.
- Huntington’s disease: autosomal dominant trinucleotide repeat disorder in which an excessive number of CAG repeats results in a polyglutamine sequence in the huntingtin protein, which leads to neurone death. It causes dementia with abnormal movements, usually presenting in middle age.
- Normal pressure hydrocephalus (NPH) presents with a triad of incontinence, gait dyspraxia and dementia (while the dementia is still mild), probably due to abnormal CSF flow, although by the time CSF pressure is measured it is in the ‘normal’ range. It may respond to shunting.
Secondary dementias occur in which the neuronal damage is due to other pathology:
- Vascular dementia (which includes multiple small infarcts and white matter ischaemia).
- Potentially reversible conditions which can present as dementia.
- Rule out any major metabolic problem especially hypo- or hyperthyroidism, hypercalcaemia, hyponatraemia, recurrent nocturnal hypoglycaemia, major organ failure (usually obvious), vitamin deficiencies, especially thiamine, folate and B12, toxicity from centrally acting drugs and alcohol, head trauma (either repetitive, e.g. punch-drunk syndrome in boxers) or the sub-acute confusion of a subdural haemorrhage following a fall and head injury, an expanding brain tumour and, very rarely in the UK now, neurosyphilis, or the dementia occurring with HIV.
