Late life depression

What is late life depression?

Depression that emerges in adults over the age of 65 is often referred to as late life depression (LLD). LLD is similar to major depressive disorder (MDD) that occurs in younger adults in many ways but has also been found to have several differences in causes, symptom presentation, and effective treatment ^[1][2].

Currently, LLD is not listed in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), thus causing the potential for LLD to be misdiagnosed, mistreated, or go entirely unnoticed ^[3][4].

Research suggests that there is a very high prevalence of depressive symptoms amongst elderly patients in care facilities, with high rates of suicide amongst this population. As such, there is a requirement for further research into LLD, in order to diagnose and treat this condition effectively ^[2][4].

LLD has been very poorly understood, with very limited research into risk factors, presentation, and treatment, but in recent years there has been an increase in research, with the aim to better understand, assess, and treat the condition ^[5].

Late life depression symptoms

Symptoms of late life depression may vary from person to person, depending on the underlying causes of their condition. Some symptoms of LLD may appear the same as symptoms of MDD but may differ in that there can be an absence of sadness or low mood ^[2][4].

Symptoms of LLD can include ^[2][4][6]:

• Suicidal ideation, which is a significant risk amongst older adults and is often an indicator of LLD
• Mood changes, including low mood
• Excessive worrying about physical and cognitive health
• Psychotic symptoms, including suspicion and paranoia
• Sleep disturbances, including insomnia and waking throughout the night
• Impaired cognitive function, including difficulties with concentration, decision-making, and completing tasks
• Reduced appetite
• Feeling very tired or low energy
• Lacking in motivation or interest
• Lacking in insight
• Reduced or impaired mobility

Late life depression causes

Risk factors and causes of late life depression can include those that are commonly seen with depression in younger adults, but there are some unique risk factors seen with LLD.

Physical health

Physical health issues have been found to be linked to the occurrence of depression at all ages, potentially due to ongoing concerns around health and possible outcomes, and because certain conditions can cause or worsen symptoms of depression ^[2].

Physical health complications become more common as people age, thus increasing this risk factor, with symptoms of depression emerging alongside conditions such as heart diseases, endocrine diseases, autoimmune disorders, and urinary tract infections (UTIs). These conditions can cause excessive worrying and impairments in self-care, thus worsening both mental and physical health ^[4][6].

Endocrine conditions, including menopause, become more prevalent with age and can cause extreme hormonal changes that may lead to or worsen depression, often requiring stabilization of estrogen levels ^[2][6].

Psychosocial factors

Similar to depression in younger adults, LLD can be caused or worsened by various psychosocial factors, many of which tend to increase in severity as people get older.

For example, social isolation and loneliness may be more prevalent in older adults, particularly those with many functional impairments. Loneliness has been found to be a significant risk factor in the development of LLD ^[2][6].

Similarly, the lack of a support system, a decline in autonomy and life purpose, and perceived helplessness can also contribute to the development of LLD ^[4].

Also, the death of a loved one is a significant risk factor in the development of depression at any age. Older adults are more likely to experience the death of their spouse or partner, which has been found to greatly increase the risk of suicide in this age group ^[2].

Neurological conditions

Depression can often be a symptom of cognitive impairment, dementia, and other neurodegenerative conditions, which are more likely to occur in older adults. Depression in the context of these conditions can be a reaction to worsening cognition, as well as being due to neurodegenerative effects, including changes in brain structure and neurotransmitter levels ^[2][5][7].

Similarly, depression may emerge following a stroke, as this can cause damage to certain areas of the brain, such as those that are responsible for decision-making, emotional regulation, and reward processes, thus impacting mood ^[2].

Medications and substances

Certain physical and mental health medications are known to cause or worsen symptoms of depression at all ages, so older adults who are prescribed several types of medication may be at increased risk of these effects ^[4].

Additionally, alcohol and illicit substances can also exacerbate or trigger symptoms of depression, particularly if used for many years. As such, long-term alcohol or drug consumption may increase the risk of LLD ^[2].

Prior mental health disorders

In some, LLD may be a continuation or relapse of a prior diagnosis of clinical depression, although research suggests that this is not commonly the case. Studies suggest that over two thirds of older adults in a care setting who present with LLD have not previously had a diagnosis of depression or experienced symptoms of the condition, thereby indicating that LLD is likely a separate condition ^[1][8].

Genetics

As with depression of any age, there may be a genetic factor in the development of the condition. Due to limited research, this link is currently unclear, but it is thought that a genetic factor for LLD may exist that differs from depression in younger adults ^[2][6].

Furthermore, research suggests that people with certain personality traits, such as those who are neurotic or obsessive, may be at an increased risk of developing LLD, which can be inherited traits ^[4].

Late life depression diagnosis

LLD is not currently listed as a separate diagnosis to major depressive disorder in the DSM-5 ^[3], thereby making it challenging to notice and diagnose. Without an appropriate assessment, symptoms of LLD can be easily missed or mistakenly thought to be solely due to physical or cognitive conditions, thus going undiagnosed and untreated ^[9].

Early diagnosis may be challenging but is often beneficial to the management of the condition, so LLD requires careful and thorough assessment. This will typically include gathering information about the individual’s history of mental and physical health conditions, the progression and current presentation of their symptoms, any current treatments and medications, and their risk of suicide ^[2][6][9].

Medical questionnaires may be utilized to ascertain the severity of certain symptoms, including symptoms of depression and cognitive impairment. This might include questionnaires such as the Beck Depression Inventory ^[10] and the Montreal Cognitive Assessment (MoCA) ^[11].

Blood, hormones, and vitamin levels are also likely to be tested, to help determine any underlying physical conditions. Depending on the individual, it may be necessary to complete a brain scan and sleep assessment to further understand their presenting symptoms ^[2].

Late life depression treatment

Treatment of late life depression will depend on the individual, the severity of their symptoms, the underlying causes of the condition, their cognitive ability, and their response to medication and therapy interventions. In some cases, treatments that are effective at managing MDD in younger adults are ineffective at treating LLD, thus complicating treatment ^[7].

Therapy

Psychotherapy may be useful for some people with a diagnosis of LLD, although this may depend on their cognitive abilities.

This may include therapies such as ^[2][7]:

• Cognitive behavioral therapy (CBT), in which individuals can learn to alter negative thoughts and behaviors and develop helpful coping strategies.
• Problem-solving therapy (PST), in which individuals can learn and utilize skills to improve functioning and set and meet goals with a structured approach.
• Interpersonal therapy (IPT), in which individuals can discuss stressful or difficult life events and emotional distress and learn how to process these occurrences, to enable them to manage negative emotions.

Medication

Medication may be less effective at managing symptoms of LLD than depression in younger adults, due to certain neurological or cognitive impairments and changes. As such, medication may depend on the individual, their symptoms, and their response to the medication. It is also possible to utilize combinations or augmentations of medications to improve treatment ^[7].

Medications for LLD typically include ^[2][7]:

• Antidepressant medications; selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, sertraline, and citalopram, and serotonin and norepinephrine reuptake inhibitors (SNRIs) such as duloxetine and venlafaxine. These medications typically cause the fewest side effects.
• Tricyclic antidepressants, such as nortriptyline and desipramine. These medications may cause unpleasant side effects but are typically effective at managing symptoms.
• Other antidepressants, such as mirtazapine and bupropion.
• Antipsychotic medications, such as quetiapine, can be utilized in combination with an antidepressant if psychotic symptoms are present or if depressive symptoms cannot be managed with an antidepressant alone.

How to manage late life depression

There are several ways to help improve or reduce symptoms of late life depression, which may be utilized by the individual themselves or may require additional support from mental health professionals.

This includes ^[2][6][7]:

• Physical activity: Being active can help prevent and improve symptoms of depression and cognitive decline, as well as improve physical health and aid medicinal treatment.
• Diet: Research shows that gut health is greatly linked to the presence of depression, so eating a healthy diet with probiotics and vitamins can improve mental wellbeing.
• Sleep: Improving sleep quality can reduce symptoms of depression, with the aid of behavioral or medicinal interventions.
• Reducing alcohol and smoking: Both alcohol and cigarettes can increase the risk of depression in later life, as well as potentially impair the effectiveness of treatment and impact physical wellbeing.

Frequently asked questions about late life depression

How does late life depression differ from depression in younger people?

Although there are similarities in LLD and depression in younger people, there are also many differences in symptoms, causes, and treatment, such as ^[1][2][7]:

• There are often fewer mood changes and depressive symptoms in LLD, with a greater prevalence of psychotic symptoms and cognitive impairment.
• Risk factors of LLD differ, in that there are more factors relating to physical health, cognition, psychosocial impairments, and neurological changes.
• Treatment options may not work as well for LLD, depending on the individual, with some being unresponsive to various medications.
• There is a greater requirement for support with self-care with LLD, such as in managing sleep, diet, and exercise, as these are likely to decline with old age and greatly impact symptoms of depression.
• There are much higher suicide rates amongst those with LLD than in younger adults with depression.

What is the average age of onset of depression?

The average age of onset of depression is thought to be between 20 and 30 years old, although there are many who experience symptoms or receive a diagnosis much earlier or much later than this. Age of onset typically differs depending on several factors, including genetic and environmental factors, social and interpersonal engagement, socioeconomic status, education level, and employment ^[12][13].

How common is late life depression?

Late life depression is believed to occur in between 1-4% of older adults living in the community, with the prevalence increasing with age ^[2][4].

Amongst older adults in care settings, the rates are believed to be much higher, with over 50% presenting with symptoms of depression, and between 14-25% meeting criteria for a diagnosis of major depression ^[2][4].