Anxiety Disorders in Older Patients

ABSTRACT

Anxiety is a mood state oriented toward a future concern associated with preparation for a possible negative event.1  In contrast, fear is an alarm response to present or imminent danger. The objective of this narrative review is to acquaint readers with the characteristics of common anxiety disorders among older people. Treatment guidelines are also provided.

METHODS

A search with no date restrictions was conducted in early 2018 for English-language articles in PubMed, Psychiatry Online, UpToDate, and OvidMD. MeSH terms used in the search included benzodiazepines, anxiety, anxiety disorders, phobic disorders, psychiatry, adult, aged, complementary therapies, phobia, social, anti-anxiety agents, tai chi, psychotherapy, accidental falls, pulmonary disease, chronic obstructive, and drug therapy. The search strategy is included in the Supplementary Appendix.

Google Scholar was used to check article citations, author affiliations, and journal impact factor. The articles1-64 chosen were frequently cited in journals, with randomized controlled trials preferred.

INCIDENCE AND PREVALENCE

Anxiety is the most prevalent psychiatric disorder, with a lifetime prevalence of approximately 29%.2  Potential predictors for persistent anxiety include poor overall quality of life and comorbid personality or mood disorders.3

Incidence of newly emerging anxiety disorders in late life is low, as they typically do not newly emerge in older people. Anxiety complaints have usually already been present in 99% of anxious individuals who are over age 65 years.2

Anxiety among chronically ill older adults is disabling.4 Elderly outpatients with high anxiety frequently visit doctors but receive relatively few mental health services.4 Among nursing home residents, pain, pharmacotherapies for depression, and suboptimal quality of life are consistently associated with anxiety.5

ANXIETY SYNDROMES

Specific phobia is an anxiety disorder that represents exaggerated or irrational fear related to a specific object or situation6 (Table 1). A study7 of the prevalence and course of specific phobia in a population of 70-year-old individuals revealed a declining frequency from 10% at age 70 to 4% at age 79. The lifetime occurrence of anxiety disorders in noninstitutionalized persons over age 65 years is 30%, with a prevalence rate of 14% among those with anxiety and a rate of 11% for those with phobias8 (Table 2).

A fear of falling is one example of a specific phobia that is especially common among older individuals and occurs in up to 50% of those in long-term facilities.9 As people age, confidence in and ability to balance may impair performance, which over time can result in isolation. Those with significant mobility limitations, but without fear of an unstable gait, are most likely to fall; thus, fear of falling may act as a protective buffer.10 In a review11 of 28 studies of elderly people, the prevalence range for fear of falling was between 3% and 85%. Fear of falling occurs in about 50% of older persons who have fallen in the previous year.12 Some factors associated with fear of falling include female sex, impaired mobility, and the need for gait assistance devices.13

• Anxiety is a common emotion that can become chronic and yield considerable dysfunction.
• Intervention includes various psychotherapies, pharmacotherapies, and stress reduction techniques.
• When prescribing, it is especially important to consider geriatric patient problems such as unstable gait, reduced metabolism, and medicinal interactions.

 Anxiety and especially depression are associated with fear of falling, with mood disorders being the most strongly connected.12 Detection and effective treatment of people with depression and anxiety are protective factors.

Polypharmacy, such as with coprescribed antidepressant and antianxiety drugs, heightens fall risks, especially among demented nursing home patients.14 People appear to fall more often when selective serotonin reuptake inhibitor (SSRI) dosages are high; however, this contention is controversial.15 With no known randomized controlled trials on this topic, there is insufficient evidence to recommend avoidance of SSRIs in older people based only on risk for falling.16

Social phobia is characterized by marked anxiety about 1 or more social situations in which the individual is exposed to possible scrutiny by others17 such as social interactions or being observed while eating or performing in public.17 There are several core symptoms of social phobia across the adult lifespan.18 These symptoms include anxiety associated with thinking about social situations, being in the social situation, remaining in the social situation too long, and avoiding such occasions.18 Additional concerns involve self-evaluations of being more nervous than others and having greater fear or avoidance than is reasonable.18 About 3% of adults experienced some social phobia in the prior year and 5% have during their lifetimes.19 People 65 years and older experience less social phobia than those who are younger.

Generalized anxiety disorder (GAD) is characterized by chronic, uncontrollable worry that interferes with function and is accompanied by restlessness, muscle tension, impaired concentration, and disturbed sleep.20 Such worries in older individuals often focus on concerns about health, finances, or disability of self or spouse.21 The prevalence of generalized anxiety without comorbidity is 1%, but up to 4% when associated with another psychiatric condition.22 The prevalence of GAD in persons over 65 years of age is lower than in younger adults, with a range in elderly people of 1%-2%.22

Panic disorder refers to recurrent, unexpected panic attacks. These emotions are surges of intense fear that peak within minutes and evidence numerous physical and cognitive symptoms.17 First-onset panic attacks occurring after age 55 are usually less severe than those starting earlier in life.23 The rate of panic disorder among those over age 55 is 1%, with a lifetime occurrence of nearly 4%.24 This condition is more common among patients reporting recent stress, poor health-related quality of life, tachycardia, or gastric ulcers.24 It is also associated with depression and being in lower socioeconomic groups. Since panic among older people has origins earlier in life, new cases are less likely over time.24 Yet, medical illnesses, use of stimulants, and drug withdrawal syndromes may contribute to panic symptoms and should remain in the differential diagnosis.25

COMORBIDITY

Anxiety and depression share some symptoms in common.1 Shared manifestations typically include a generalized distress factor.  Anhedonia is specific to depression, whereas hyperarousal is related to persons with anxiety.1

Older persons experience comorbidities to a similar extent as younger adults; depressive and anxiety disorders frequently coexist across the lifespan.26 In a study by Lenze and colleagues,27 approximately 35% of older subjects with depression had at least 1 lifetime anxiety disorder, and 23% had a current diagnosis. The most common anxiety disorder diagnoses were panic disorder, specific phobia, and social phobia.27

Anxiety has links to coronary artery disease, but disparate findings are cited regarding postmyocardial infarction anxiety.28 Older adults who experienced a heart attack and are also anxious have more adverse cardiac events.29,30 Postmyocardial infarct anxiety-induced complications exist beyond the effects of depression31; yet, the validity of such contentions are not universally confirmed. An analysis of people after an infarct revealed that anxiety assessments were affected by the severity of heart disease, physical inactivity, and depression.31 Yet, postinfarction anxiety was not associated with more cardiovascular events or death.31

Patients with chronic obstructive pulmonary disease (COPD) are more likely to develop anxiety disorders compared with healthy controls.32 The development of anxiety among patients with COPD results in a compromised prognosis.32 Anxiety disorders are disabling in this population and without intervention can become chronic, thereby lowering self-esteem, predisposing to suicidal ideation, and increasing hospitalization rates.33 Both patients and caregivers may become overwhelmed and find it difficult to cope with such difficulties.

Patients with COPD also have a high prevalence of social and specific phobia.34 Socially phobic persons with COPD often are embarrassed by breathlessness, sweating, and urinary incontinence.34 Those with specific phobia fear certain circumstances or the idea of being without medication.34 Such patients frequently avoid leaving the house without their medication and minimize activities likely to cause breathlessness.34

Anxiety is associated with cognitive impairment and dementia.35 Depression and anxiety disorders in midlife are risk factors for dementia.36 Within this population, anxiety has a moderate incidence and persistence.37 Chronic anxiety is associated with reduced cortical brain thickness; yet, in a Mayo Clinic study38 after adjusting for comorbid depression, only the association between anxiety and reduced insular thickness was significant. The prevalence of anxiety in patients with Parkinson’s disease is higher than in healthy and comparably disabled elderly subjects.39

TREATMENT

Management

The elderly patient and family should be informed that treatment of anxiety is important to improve health and quality of life.40 Collateral information from family and caretakers is helpful for a complete history. Physicians should to be aware of prior therapies for anxiety and response. All medications that might be anxiogenic such as anticholinergic agents, antihistamines, steroids, sympathomimetic compounds, stimulants, and dopaminergic drugs should be reviewed.41 Ingestion of coffee, tea, and other caffeine sources and illicit stimulant drugs should be avoided.41 Coexistent anxiety and depression is frequent and requires treatment.40 Close follow-up with discussion of possible medication side effects enhances compliance.40 It is essential to monitor for suicidal ideation and symptom change, and symptom decline indicates clinical improvement.40

Psychotherapy

Cognitive behavioral therapy (CBT) benefits older patients with GAD.42 CBT has been shown to diminish worry and depressive symptoms, with improved mental health among older persons with GAD; however, that is not always consistently so.43

Exposure therapy is recommended for patients with specific phobias.44 Phobic severity, anxiety, and avoidance can be lessened when applied in combination with other psychotherapies.44 Treatment gains are maintained for 1 year, but exposure therapy yields high dropout rates and low treatment acceptance.45

Tai chi is effective in reducing falls and fear of falling in older adults (Table 3).46 Its greatest benefit is enhancement of balance confidence.46 Tai chi is a system of gentle physical exercise and stretching that develops flexibility and coordination.47 Individuals are challenged to move through positions with a reduced base of support—standing on 1 leg is an example.48 Tai chi also promotes relaxation, awareness, and focus and is a form of physical therapy.47

Psychological interventions reduce anxiety and depression in demented patients by helping them learn better ways to cope with these symptoms.48 Psychotherapies compare favorably with pharmacologic treatments.49

Pharmacotherapy

Drug treatment often has better efficacy than psychotherapy in people with late-life anxiety.50 The usual first-selected treatment for anxiety disorders, with the exception of specific phobias, are the SSRI or serotonin-norepinephrine reuptake inhibitor (SNRI) drugs.51 Escitalopram and paroxetine are effective for specific phobias.52-54 Tricyclic antidepressant drugs are usually a second-choice option because of anticholinergic side effects, weight gain, sedation, and potential for lethal overdose.51 Other pharmacotherapies not approved for anxiety disorder management include monoamine oxidase inhibitors, mirtazapine, gabapentin, pregabalin, hydroxyzine, and antipsychotic drugs.

Pregabalin has efficacy for patients with GAD.51 Pregabalin acts on the α2δ subunit of calcium channels to reduce neurotransmitter release.51 Gabapentin has a similar mechanism in off-label prescribing.51 Lamotrigine may inhibit voltage-dependent sodium channels to decrease glutamate release. Lamotrigine can diminish panic in some people.55 All 3 of these drugs are anticonvulsant medications.

d-Cycloserine is an N-methyl-d-aspartate (NMDA) partial agonist prescribed off-label to augment exposure therapy.51 Although not effective in monotherapy, it can facilitate fear extinction.56 Additionally, d-cycloserine reduces reactivity to phobic stimuli in subjects with a specific phobia, as documented by functional magnetic resonance imaging.57 d-Cycloserine combined with exposure therapy can lead to sustained changes in the ventromedial and prefrontal cortex response to phobic stimuli.57

Benzodiazepines are often prescribed to older patients with anxiety. However, they are usually indicated only for short-term applications, as when adults experience infrequent anxiety symptoms, eg, flight phobia.58 Close physician monitoring is required when prescribing benzodiazepines, as anxiety in older people tends to become a chronic condition.4 Among sustained benzodiazepine users, only a small proportion use higher doses than recommended.59 Favorable features of benzodiazepines include a lack of metabolic or sexual side effects and quick alleviation of anxiety.60 These drugs are well tolerated and safe in oral monotherapy. When used on an as-needed basis, however, they might reinforce maladaptive behavior.40 The practice of prescribing anxiety medication for immediate relief may prolong anxiety for an extended period of time.40 There is greater dependence potential with short versus long half-life benzodiazepines.61 Physicians should use caution to avoid drug dependence. The risk-to-benefit ratio of this pharmacotherapy in older people is generally less favorable.61

Benzodiazepines induce a heightened risk for falls and hip fracture—dosages greater than 3 mg/d of diazepam equivalent increased the risk of hip fracture by 50%. Such injuries usually occur shortly after initiating therapy.62 Large dosages should be avoided. Short half-life benzodiazepine versions may not be safer than the long half-life versions; yet, falls occur more often with long elimination half-life benzodiazepines, especially when prescribed in combination with other drugs.63

Since benzodiazepines are eliminated slowly from the body, prolonged treatment with repeated doses often results in adipose tissue accumulation, dependence, and potential drug withdrawal.64 Impaired cognition can also occur. Thus, when benzodiazepines are utilized in older people, those with a short elimination half-life are usually preferred.63 Nevertheless, many people have been safely prescribed these medications for decades with no misuse or clinical concerns.

CONCLUSION

CBT has the best efficacy among the psychotherapies in treating elderly people with anxiety. Among pharmacotherapies, SSRI and SNRI drugs provide the greatest benefit in these patients.

Submitted: May 31, 2018; accepted September 17, 2018.

Published online: January 31, 2019.

Potential conflicts of interest: None.

Funding/support: None.

Supplementary material: See accompanying pages.

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