Is Depression & Anxiety common in Parkinson’s disease?

Yes.

Depression & Anxiety are common in Parkinson’s disease. These problems can produce significant disability.  About 1 in every 5 patients with Parkinson’s disease may have depression (Rejinders et al 2008). Anxiety is even more common – about 1 in 4 patients with Parkinson’s disease have significant symptoms of anxiety (Broen 2016).

Depression is common in Parkinson’s disease. Thankfully, detection and treatment is helpful in almost all cases.

Other than these two problems, patients with Parkinson’s disease can also have other psychiatric issues.

  • Impulse control Disorders: Patients may have difficulty in controlling their impulses. They may start spending a lot of money online, or may start gambling or have excessive weight gain due to eating too much. This is particularly more common if Parkinson’s disease is being treated by a group of medications called “Dopamine Agonists” (Pramipexole, Ropinirole, Rotigotine).
  • Agitation and hallucinations / psychosis: This is particularly worrisome and needs to be appropriately treated to prevent injury to family members. Medications such as Quetiapine, Donepezil, Pimvanserin and if all else fails – Clozapine – are usually helpful.

Let us focus on depression here. We can discuss Impulse control disorders and Agitation/Psychosis in a future article.

Relevant references:
1. Prevalence of anxiety in Parkinson’s disease: A systematic review and meta-analysis. Broen et al Mov Disord. 2016 Aug;31(8):1125-33
2. A systematic review of prevalence studies of depression in Parkinson’s disease. Reijnders et al Mov Disord. 2008 Jan 30;23(2):183-9

What are the symptoms of Depression or Anxiety?

Most people believe that all patients with depression actively cry, talk to people about their mental pain, or in some way express their grief actively. This is frequently not the case.

Many people with Parkinson’s disease have a passive form of depression. This passive depression may manifest in the following ways:

Symptoms of 'Passive' Depression
1. Feeling guilty, worthless or hopeless.
2. Loss of interest in previously enjoyable activities (for example, watching a movie)
3. Fatigue or loss of energy.
4. Thinking about the same things over and over again (Obsessive ruminations)
5. Difficulty in paying attention, concentrating or remembering things
6. Reduced or increased appetite. Losing or gaining weight without a clear cause.
7. Sleeping too much or too little. Early morning awakening.

Inability to focus or lack of interest in regular activities may be a sign of depression.

In fact, patients with Parkinson’s disease may become so passive that they are then diagnosed with a related psychiatric condition called “Apathy” – or a complete lack of interest and motivation.

Is there a test for Depression & Anxiety?

There is no test to confirm the diagnosis of depression and anxiety. This diagnosis can only be made after you have a detailed conversation with your doctor or a qualified mental health professional.

However there are numerous, fairly accurate screening questionnaires for Depression. One of them is the PHQ-2 Questionnaire, which is reproduced below.

PHQ-2 Questionnaire

In the last two weeks, how often did you have little interest or pleasure in doing things? – Not at all (0 points)
– Several days (1 point)
– More than half the days (2 points)
– Nearly every day (3 points)                                                                                             .
In the last two weeks, how often did you feel down, depressed or hopeless? – Not at all (0 points)
– Several days (1 point)
– More than half the days (2 points)
– Nearly every day (3 points)

Add up your points for the two questions. If your score is 3 points or more, you may be suffering from depression. Please remember that even if this questionnaire indicates you may have depression, the diagnosis needs to be confirmed by a doctor.

Why is Depression and Anxiety common in Parkinson’s disease?

We could assume that depression is common because of the significant problems with movement in Parkinson’s disease. This intuitive assumption certainly is true up to a certain extent.

However, a major cause of depression in Parkinson’s disease is due to chemical changes inside our brain which are caused by the disease. In fact, Depression can actually happen even before the movement problems of Parkinson’s disease start. The exact mechanism by which accumulation of synuclein causes depression is still being worked out.

The leading theory is that just like synuclein causes damage to brain cells that secrete Dopamine, it also causes damage to brain cells that produce a chemical called “Sertonin”. Serotonin (just like Dopamine) is one of the chemicals in the brain that causes feelings of happiness or satisfaction. Therefore, a decrease in the activity of this chemical causes Depression.

Serotonin makes you happy.

What are the natural / no-medication methods for treatment of depression?

Depression should not be neglected. But all cases of depression do not need medication. Counselling and exercise can be beneficial in many cases.

  1. Exercise: Any form of exercise decreases Depression and Anxiety. The effect is marked. In non-Parkinson’s disease patients, exercise can have the same effect on depression as taking an antidepressant medication.

    Even walking in the open for 15-30 minutes daily can help with depression.

  2. Counselling: Cognitive behavioral therapy in particular, may be very helpful. An insider tip – sometimes psychiatrists may not have adequate time to participate wholeheartedly in counselling because of their extremely hectic schedule. You can request referral to a professional counselor if you want to try counselling.

    Talking to a trained professional about your depression can be very helpful

  3. Bright light therapy: This is useful if your depression is seasonal i.e. it is worse in winter when you get less sunlight. This kind of depression is called “Seasonal Affective Disorder” or SAD. You can buy “daylight spectrum” bright lights online (see an example below) and keep these on in your house for at least 8 hours a day. Regular use of these lights has been clinically proven in decreasing depression due to SAD.

    Bright lights can help with winter-time depression. If specialized lamps are not available, you can try using commonly available bright fluorescent tubes.

Even in patients who need medication, participating in a regular exercise program and counselling leads to greater relief than taking the medication alone.

Which anti-depressant medications are safe in Parkinson’s disease?

Since low levels or Serotonin could be one of the reasons for Depression in Parkinson’s disease, medications which increase serotonin activity are helpful. These medications are SSRIs (short for Specific Serotonin Reuptake Inhibitors). A few examples of these medications are Escitalopram, sertraline, fluoxetine etc.

Serotonin makes you happy. One more “happy” chemical is Dopamine itself.

While these medications focus on Serotonin, we should not forget that Dopamine itself is also a “happy” hormone. The core medications for Parkinson’s disease which increase the activity of Dopamine in the brain also relieve depression. Pramipexole in particular has been clearly shown to improve depression in Parkinson’s disease patients.

It is best to avoid certain other psychiatric medications:

  • There are other types of antidepressants e.g. one type is called TCAs (Tricyclic Antidepressants). However they may not be as effective as SSRIs. In addition, many TCAs have additional unwanted side-effects such as drying of the mouth making it more difficult to swallow, difficulty in passing urine, and occasionally confusion. They may also increase the risk of falls.
  • Benzodiazepines are medications that are commonly used to placate patients who have extreme anxiety. But these medications increase the risk of falling in Parkinson’s disease and are best avoided.

Certain antidepressants and sedatives can increase falling.

Isn’t is “reasonable” to be depressed if I have Parkinson’s disease?

No. On the contrary, facts suggest that there is very good reason for optimism.

I would like to remind you that:

  • A large number of scientists and doctors are furiously researching novel treatments for Parkinson’s disease.
  • New medications and formulations for Parkinson’s disease are being made available almost every year.
  • Even with the current medications and with Deep Brain Stimulation (DBS), Parkinson’s disease can be satisfactorily controlled in most patients.
  • Hoping for a cure for Parkinson’s disease is perfectly reasonable.
  • Each one of the 4 points above is 100% true.

Believe. Perhaps the cure for Parkinson’s disease is closer than any of us can imagine.