Depression can strike anyone, but people with Parkinson's disease, a progressive brain disorder affecting more than 500,000 Americans,¹ may be at greater risk. Treatment for depression helps people manage both diseases, thus improving the quality of their lives.

The true prevalence of depression among people with Parkinson's disease is difficult to determine because there are no standardized assessment tools designed to evaluate depressive symptoms in the context of this illness. However, it is estimated to be quite common—as many as half of people with Parkinson's may suffer from depression.²

Despite the enormous advances in brain research in the past 20 years, depression often goes undiagnosed and untreated. People with Parkinson's, their families and friends, and even their physicians may misinterpret depression's warning signs, mistaking them for inevitable accompaniments to Parkinson's disease. In addition, men, who are more likely to develop Parkinson's, are more likely than women to have difficulty acknowledging depression.

Symptoms of depression may overlap with those of Parkinson's and other physical illnesses. However, skilled health professionals will recognize the symptoms of depression and inquire about their duration and severity, diagnose the disorder, and suggest appropriate treatment.

Depression Facts

• Persistent sad, anxious, or "empty" mood
• Feelings of hopelessness, pessimism
• Feelings of guilt, worthlessness, helplessness
• Loss of interest or pleasure in hobbies and activities that were once enjoyed, including sex
• Decreased energy, fatigue, being "slowed down"
• Difficulty concentrating, remembering, making decisions
• Insomnia, early-morning awakening, or oversleeping
• Appetite and/or weight changes
• Thoughts of death or suicide, or suicide attempts
• Restlessness, irritability

If five or more of these symptoms are present every day for at least two weeks and interfere with routine daily activities such as work, self-care, and childcare or social life, seek an evaluation for depression.

Depression is a serious medical condition that affects thoughts, feelings, and the ability to function in everyday life. Depression can occur at any age. NIMH-sponsored studies estimate that almost 10 percent of American adults, or about 19 million people age 18 and older, experience some form of depression every year.³ Although available therapies alleviate symptoms in over 80 percent of those treated, less than half of people with depression get the help they need.^{3, 4}

Depression results from abnormal functioning of the brain. The causes of depression are currently a matter of intense research. An interaction between genetic predisposition and life history appear to determine a person's level of risk. Episodes of depression may then be triggered by stress, difficult life events, side effects of medications, or other environmental factors. Whatever its origins, depression can limit the energy needed to keep focused on treatment for other disorders, such as Parkinson's disease.

People with depression who have Parkinson's disease have a different symptom profile than those without Parkinson's.² The Parkinson's profile includes higher rates of anxiety, sadness without guilt or self-blame, and lower suicide rates despite high rates of suicidal thoughts. Hormonal imbalances such as hypogonadism and hypothyroidism, which can cause depressive symptoms, need to be looked at carefully in these individuals. More research is needed to understand the relationship between Parkinson's disease and depression, dementia, anxiety disorders, and psychosis.

Parkinson's Disease Facts

Parkinson's disease is a chronic and progressive disorder of the brain primarily affecting the motor system, but also affecting thinking and emotion. It results from the loss of brain cells that produce dopamine, a chemical messenger that controls movement. The four primary symptoms of Parkinson's are tremor or trembling in hands, arms, legs, jaw, and face; rigidity or stiffness of the limbs and trunk; bradykinesia, or slowness of movement; and postural instability, or impaired balance and coordination. Individuals may also have difficulty walking, talking, or completing other simple tasks. Early symptoms are subtle and occur gradually. At present, there is no way to predict or prevent Parkinson's disease.

Parkinson's disease affects both men and women. The disease is considerably more common in the over-50 age group. With the increased life expectancy in this country and worldwide, an increasing number of people will develop Parkinson's disease.

A variety of medications provide dramatic relief from the symptoms. However, no drug yet can stop the progression of the disease, and in many cases medications lose their benefit over time. In such cases, surgery may be considered. Some doctors recommend physical therapy or muscle-strengthening exercises. Some new drugs have recently been approved offering a wider choice of medications for individuals with Parkinson's, while others are under investigation in this country and overseas in an effort to obtain better therapeutic results with fewer side effects. Ongoing research is aimed at discovering the cause of Parkinson's disease, finding better treatments, and ultimately preventing and curing the disorder.