Efficacious retrial of electroconvulsive therapy for major depressive disorder after a prolonged seizure in an older adult

Abstract

This is a case of a woman in her 70s with treatment-resistant major depression who was admitted psychiatrically for the fifth time in 1.5 years. She had a history of intensive psychotherapy and psychotropic medication trials with poor efficacy. She also had a history of adverse complications to electroconvulsive therapy (ECT) with prolonged seizures and postictal confusion during her third hospitalisation. At her fifth hospitalisation, due to poor response to routine psychiatric treatment, ECT was pursued. We discuss challenges in pursuing ECT and the outcome of the retrial of an acute ECT series, in the context of a paucity of similar literature regarding geriatric depression.

Background

Electroconvulsive therapy (ECT) is a Food and Drug Administration-approved class II device for severe major depressive episodes in patients 13 years and older who are treatment resistant or require a rapid response.¹ Efficacy of ECT requires induction of a grand mal seizure by overcoming one’s seizure threshold. Sex, medications, skull density, past seizures, ventilation status, and significantly, in this case, age, all influence this threshold.² ECT has been shown to have great efficacy in the geriatric population as shown in the Prolonging Remission in Depressed Elderly Study, which enrolled 240 patients over the age of 60 years and yielded a 70% response rate and 62% remission rate. Their work also revealed that patients over 70 years are 1.89 times more to respond than those 60–69 years old.³ Spaans et al demonstrated that ECT was faster and had a higher remission rate as compared with medication (63.8% vs 33.3%) in older adults.⁴

However, ECT is not without risk. The most common adverse effects include headaches, myalgias and nausea. Headache has been reported in 26%–85% of patients, which usually subsides in 24 hours. Myalgias are common, yet severity appears to decrease with each subsequent session. Lastly, Andrade et al believe post-ECT nausea appears to be more so related to headache or anaesthesia than ECT.⁵ Changes in cognition that can be very concerning for patients are of transient duration consisting of confusion and amnesia lasting less than 1 hour. It is important to consider the patient’s age and the presence of grey or white matter disease with or without dementia as this can increase post-ECT confusion, and that these cognitive side effects have been shown to resolve.⁵ Nevertheless, there are no absolute contraindications to ECT, even in patients who have experienced side effects with prior treatments. Specifically, there is insufficient literature regarding the retrial of an acute ECT series in older adults with a major depressive episode who have had prolonged seizures with a previous ECT series.

Case presentation

The patient was involuntarily admitted to the older adult inpatient unit due to worsening anxiety and depression with daily suicidal ideation that began 1 month before admission. She had been experiencing worsening depression since her husband died and had attempted multiple outpatient treatments including psychotherapy and medication management. Psychotherapeutic methods included acceptance and commitment therapy, cognitive–behavioural therapy and supportive psychotherapy. Prior pharmacotherapy included adequate dose and duration trials of lorazepam, duloxetine, venlafaxine, citalopram, paroxetine, buspirone, escitalopram, bupropion, sertraline and hydroxyzine. She was psychiatrically hospitalised four times prior to the current hospitalisation. At admission, she presented as sleepy though restless, fully oriented, conversationally normal, not responding to internal stimuli and ‘depressed’ with a dysphoric affect. Memory and executive function were impaired at intake; the patient also reported daily active suicidal ideations without a plan. The patient met criteria for major depressive disorder: recurrent, severe, without psychotic features due to reported anhedonia, difficulty initiating and maintaining sleep, guilt, poor concentration, decreased appetite with weight gain, psychomotor slowing and suicidal ideations without attempt. Criteria were also met for generalised anxiety disorder with a specifier of panic attacks. She displayed cognitive deficits with executive dysfunction and impairments in problem-solving and planning. For diagnostic clarification, the patient received neuropsychiatric testing, which revealed a mild neurocognitive disorder potentially contributing to her depression.

Her psychiatric history reveals an inpatient admission 6 months prior for a similar presentation. During that admission, the patient was trialled on medications however was found to be treatment refractory for several antidepressants. ECT was discussed with the patient, who signed informed consent after reviewing an informational video as well as meeting with neuromodulation staff for an evaluation. She was started on a regimen of ECT three times weekly. During her fourth ECT session, the patient had a 489-second prolonged central seizure requiring a total of 2 mg of midazolam to abort the seizure. This adverse effect was followed by impairments in cognition with disorientation, short-term memory and executive dysfunction. Medical workup, including blood work, electroencephalogram (EEG) and a head CT scan, to rule out other aetiologies, was negative. The patient’s medications at the time of ECT included psychotropics (duloxetine 60 mg daily, mirtazapine 45 mg nightly, risperidone 1 mg two times per day), and there was no evidence of medication-related delirium. The ECT psychiatrist who performed her fourth ECT treatment and the director of the ECT clinic were consulted; they too were concerned that this presentation was unusual and atypical. After 7 days, the patient’s cognition improved to her baseline. Remarkably, the patient’s depression and anxiety also appeared to be in remission. The patient remained inpatient for 8 days after her last ECT session and was discharged able to function. She was safely discharged with home health and outpatient mental health follow-up (figure 1).

Figure 1.

Treatment details throughout the patient’s two acute ECT series. Figure produced by Joseph Kramkowski. ADLs, activities of daily living; ECT, electroconvulsive therapy; EEG, electroencephalogram; MOCAs, Montreal Cognitive Assessments.

Investigations

At current intake, the patient underwent an ECG, showing a stable historical inferior infarct, and a lower extremity ultrasound without concern for deep venous thrombosis. No brain imaging was performed as criteria were not met; however, a head CT scan from 6 months earlier did not show any identifiable lesion that could be contributing to her presentation. Blood work included a complete blood count, comprehensive metabolic panel and thyroid function testing pertinent for a sodium level of 131. A presumed positive urinalysis resulted negative after culture. Urine drug screen and COVID-19 testing were negative.

Treatment

The patient’s anxiety while inpatient would manifest somatically as episodes of diarrhoea, stopping many interviews early to use the restroom. She was trialled on gabapentin for a short course specifically for somatic symptoms of anxiety but saw no improvement. Next, a brief course of low-dose lorazepam was started as a more robust anxiolytic. She was tapered off her home psychotropics of a daily total of 3.5 mg risperidone and 60 mg of mirtazapine due to lack of efficacy, weight gain and extrapyramidal side effects. After the taper was completed, the patient was started on nortriptyline and buspirone for anxious depression. The nortriptyline dose was adjusted based on response and intermittent blood levels, settling at 100 mg daily at discharge with no evidence of anticholinergic side effects. Lastly, she was titrated to 45 mg daily of buspirone.

Given a history of prolonged seizure, the treatment team was hesitant to recommend ECT; however, due to a refractory depression, ECT was recommended to the patient and her family. This decision was made as she had a good symptomatic response to her previous series and prolonged seizure is not an absolute contraindication for subsequent ECT. As no decrease in efficacy has been shown,⁶ it was advised that she receive bilateral ECT to decrease the likelihood of prolonged seizures as experienced with past unilateral ECT.⁷ The patient signed informed consent to start an acute series of ECT and recorded a fair response after the first treatment. Before starting ECT, she declined to complete any standardised rating scales for depression or anxiety. Before the second ECT treatment, she completed a Patient Health Questionnaire-9 (PHQ-9) with a score of 27 but refused other assessments. Lorazepam was tapered off after fourth treatment due to improvement in anxiety to minimise cognitive side effects secondary to benzodiazepine use. Prior to her fifth treatment, there was an improvement in the patient’s depression clinically and objectively with a PHQ-9 of 21. She received six treatments on a three times a week basis. Thereafter, ECT was held due to pharyngeal infection and decline in attention, visuospatial/executive functioning and speech. As ECT was being held, she was started on aripiprazole for mood augmentation, and titrated to 5 mg daily. She also received serial Montreal Cognitive Assessments (MOCAs); the patient’s first MOCA was 15 out of 30 which increased to 28 out of 30 over 12 days. The patient continued to report mild depressive symptomatology; thus, another inpatient ECT session was performed after consent.

Outcome and follow-up

Thereafter, the patient was noted to have improvements in sleep, energy, mood and motivation. She was no longer reporting distressing thoughts about her husband. The patient agreed to outpatient maintenance ECT treatments due to the perceived benefit. She has continued outpatient therapy and reports low depression and anxiety, good sleep and appetite, and denies suicidal thoughts.

Discussion

Therapeutic options for treatment-resistant depression remain a challenge and ECT is usually considered an evidence-based treatment as a viable treatment option. This case highlights the benefits of pursuing an acute ECT series for a recurrent severe major depressive episode in an older adult who had experienced post-ECT delirium and prolonged seizure during a previous acute ECT series. After reviewing the literature, a similar report of a second acute course of ECT after a prolonged seizure was not found. While prolonged seizures have been seen in the literature, an account of retrial especially in older adults appears to be without report. The literature provides some similar cases in terms of outcomes with prolonged seizures. One such report described a man in his 40s with major depressive disorder with psychotic features who was enrolled in an ECT clinical trial. The patient appeared to have some neurocognitive impairment at baseline. This patient received eight bilateral ECT treatments (80 Hz, 1.5 ms, 1.25 s, 0.8A: 96 mC). On the patient’s eighth treatment, he experienced a seizure that lasted 402.5 s on the left EEG channel. In contrast to our patient, the patient appeared to be less confused, more verbal and more goal oriented than in previous post-treatment periods. The patient continued to have four additional treatments without further incident; however, clinical response was overall. The patient was trialled on other medications and eventually discharged with marked improvement.⁸

ECT is an important treatment modality in the geriatric population indicated for severe depressive illness, mania, schizophrenia and other neuropsychiatric conditions.⁹ While the American Psychiatric Association quotes no absolute contraindications to ECT and further research has demonstrated that prolonged seizures or acute cognitive impairment is a not relative contraindication,^{9 10} the patient’s history and past experiences with treatment are an important part of developing a treatment plan.

In summary, this case demonstrates the utility of a retrial of ECT for treatment-resistant geriatric depression in patients who experience both a prolonged seizure and negative cognitive effects. This patient benefited from ECT more than any previous pharmacological treatment and she experienced her second acute ECT without a prolonged seizure. When presenting information to patients and families, it is important to highlight both the positive evidence for the use of ECT and the possible adverse effects. In this case, it was important to highlight the efficacy that the patient had with her last treatment in conjunction with the evidence that ECT is safe and effective. However, it is important to personalise the treatment for the family; cognitive effects were their primary concern and this case occurred during the COVID-19 pandemic when family visitation was restricted. It was imperative to answer questions fully and demonstrate a plan to monitor their loved one’s cognition. The treatment plan must be made using available evidence to produce the highest likelihood of the patient achieving their goals for treatment.

Learning points.

• Electroconvulsive therapy (ECT) is safe and effective in older adults who experience transient cognitive decline in relation to prior ECT therapy.

• Prolonged seizures and confusion, if resolved, are not contraindications for continued or a retrial of ECT.

• Subsequent acute series of ECT can be effective in patients who did not see a complete response in their first series.

Ethics statements

Patient consent for publication

Obtained.