Sad or hopeless feelings
About 40 to 50 percent of people with Parkinson's develop depression. Usually it's mild to moderate in intensity, but roughly 5 to 10 percent of cases are the more severe form known as major depression. Evidence suggests that depression results partly from neurochemical changes in the brain caused by the Parkinson's disease process -- it's not just a psychological reaction to having the illness.
Diagnosing depression in a person with Parkinson's disease can be complicated, because the two disorders share many symptoms: fatigue, loss of pleasure or interest in normal activities, problems with sleep, slowness of movement, lack of facial animation. Parkinson's patients may look sad even when they're not, because on top of having stiff facial muscles, they speak softly and don't respond quickly.
To correctly identify the mood disorder, doctors look for distinguishing clues such as sustained feelings of sadness, worthlessness, guilt, or irritability. Depression can be treated with psychotherapy and drugs, such as selective serotonin reuptake inhibitor (SSRI) drugs or tricyclic antidepressants. In severe cases, electroconvulsive therapy may be considered.
Anxiety
About 40 percent of Parkinson's disease patients struggle with anxiety, often in tandem with depression. So-called generalized anxiety makes individuals so worried and edgy that they can't sleep or they experience a racing heartbeat, shortness of breath, and sweating. Such symptoms can be provoked by distress and embarrassment over how others may react to seeing their Parkinson's tremor or shuffling gait, and the problem can hurt their ability to perform at work or enjoy social gatherings. Even worse, anxiety itself can aggravate Parkinson's motor symptoms.
People with Parkinson's also often suffer anxiety when their levodopa or dopamine agonist drugs start wearing off. They fear that the next dose won't control their symptoms again, or that they'll be stranded out in public, unable to move well. Extreme anxiety can produce scary panic attacks that leave the patient unable to breathe and feeling as if he's having a heart attack. For some, social situations provoke such an intense bout of nerves that they develop a social phobia and shun any gatherings.
Anxiety disorders can be allayed with SSRI antidepressants or antianxiety drugs such as Valium.
