Electroconvulsive therapy in older adults

Definition and utilisation. ECT is the delivery of a brief electric current to the brain under general anaesthesia and muscle relaxation to produce a generalised cerebral seizure, given in a course of typically 6–12 treatments, two to three times per week. Older adults constitute more than one-half of all patients who receive ECT for depression, yet it remains under-utilised despite its relative safety and high effectiveness.

Indications. Severe depression with somatic complications, severe suicidality, catatonia, and refusal of food and fluids — here immediate initiation of ECT is indicated. Psychotic depression. Pharmacotherapy-resistant depression. Also refractory mania, severe and treatment-resistant persistent agitation and aggression in dementia, and neuroleptic malignant syndrome. ECT should be considered a first-line option in all patients with severe depressive symptoms, especially where psychotic symptoms are present — it is not a last resort.

Efficacy and the age effect. ECT is probably more effective in more severe depression in older people than in younger adults, and remission rates in psychotic depression exceed 70–80%. The efficacy of ECT does not diminish with advancing age, but the seizure threshold increases, so higher stimulus doses are needed. Older age is a predictor of better response to ECT. ECT rapidly relieves expressed suicidal intent.

Pre-ECT assessment. Confirm the indication and document informed consent — from the patient if capacity is present, otherwise from the nominated representative under the Mental Healthcare Act 2017, which prohibits ECT without anaesthesia and muscle relaxants and bars its use in minors without Mental Health Review Board permission. Assess cardiovascular and respiratory fitness, cervical spine and dentition, and cognition (baseline MMSE/MoCA); obtain CBC, electrolytes (mEq/L), glucose (mg/dL), renal and liver function, ECG, and chest X-ray; review drugs — stop or reduce benzodiazepines and anticonvulsants (they raise the seizure threshold), continue antihypertensives, and withhold lithium.

Adverse effects. ECT has remarkably few side effects in older age, with reversible cognitive side effects the most common feature — post-ictal confusion, anterograde amnesia and retrograde amnesia, usually resolving within weeks, though patchy autobiographical memory gaps may persist. Others: transient hypertension, tachycardia and arrhythmia, headache, myalgia, nausea, prolonged seizure, and anaesthetic risk. There is no absolute age limit and no absolute contraindication; raised intracranial pressure, recent myocardial infarction, recent stroke, unstable aneurysm and severe cardiac disease are relative contraindications requiring specialist assessment.

Technique, continuation and alternatives. Right unilateral electrode placement reduces cognitive effects compared with bitemporal, at the cost of needing a higher stimulus dose; brief and ultrabrief pulse widths further limit memory impairment. Relapse is high after a successful course, so give continuation pharmacotherapy (antidepressant with or without lithium) or continuation/maintenance ECT. Transcranial magnetic stimulation is a non-invasive alternative for depression resistant to at least one antidepressant, approved also for OCD, and carries lower risks than antidepressants, but should be used judiciously where there is seizure risk after stroke or traumatic brain injury.

ELEKT-D trial (NEJM 2023). In treatment-resistant major depression without psychosis, subanaesthetic intravenous ketamine was non-inferior to ECT with fewer cognitive adverse effects — providing an option where ECT is refused, unavailable or contraindicated. ECT nevertheless remains superior and first-line in psychotic depression, catatonia and acute suicidality, all of which were excluded from that trial. Current practice increasingly favours right unilateral ultrabrief-pulse ECT, which achieves comparable efficacy with substantially less cognitive impairment in older adults. Exam one-liners: ECT = brief current under anaesthesia + muscle relaxant → generalised seizure · >50% of ECT recipients for depression are older adults · efficacy undiminished by age but seizure threshold rises · older age predicts better response · commonest adverse effect is reversible cognitive impairment · no absolute contraindication · MHCA 2017 prohibits unmodified ECT · relapse is high — always give continuation treatment.