Imagine being sick for a long time—maybe even a lifetime—and not knowing it. Persistent Depressive Disorder (PDD) affects people that way. It’s a stealthy illness, hard to detect, yet quietly disabling.
Persistent Depressive Disorder—the depression formerly known as dysthymia—is a chronic, milder form of Major Depressive Disorder (MDD). The symptoms for both are the usual suspects in depressive illness: a down mood, fatigue, despair, trouble eating and sleeping, and poor concentration.
In adults, it takes two symptoms and two years to establish a Persistent Depressive Disorder diagnosis. During that time, patients may feel fine for up to two months at a time. They could also flame into a major depressive episode. But where Major Depressive Disorder boils and cools, Persistent Depressive Disorder simmers at a low, slow burn.
Causes and risk factors
Persistent Depressive Disorder strikes roughly 2 percent of Americans in a given year. Why them? Heredity, age, social standing, and mental health history explain a lot.
Chronic depression runs deep in the gene pool. Genetics influence everything from the age when symptoms first appear to how long and severe the depression will be. The patient’s closest relatives are the most vulnerable, but the extended clan isn’t spared, either. PDD in the family also increases risk for attempted suicide, panic, or substance use disorders.
Persistent Depressive Disorder typically shows up around age 20. People who lose a parent during childhood, who grow up in a difficult family environment, or who develop anxiety disorders early in life are likely to get a PDD diagnosis before age 18. Patients with long histories of PDD may also mistakenly grow to accept the disorder as their “normal.”
Persistent Depressive Disorder affects more women than men and the divorced more than the married. PDD risk also increases for people who lack social or economic power, based on factors such as education, occupation, and income. Race makes a difference, too: PDD affects more Native Americans and white people than blacks, Asians, or Hispanics.
People who have anxiety or personality disorders are extra-susceptible to Persistent Depressive Disorder.
Research suggests that, like all forms of chronic depression, Persistent Depressive Disorder likely results from a disconnect within the brain circuitry that regulates mood and stress. Increased activity in the brain’s emotional centers brings on the signature gloom of depression, while decreased activity in the executive areas impairs attention and drains energy.
Diagnosing Persistent Depressive Disorder
Frequently, after hearing a complaint of longstanding pain and sadness, the doctor will look for these diagnostic clues:
The number one characteristic is a depressed mood. People suffering from Persistent Depressive Disorder experience low mood for the majority of days for two years without a break for longer than two months.
During this time, patients endure at least two of six additional symptoms.
- Weight fluctuations. People with PDD may lose or gain noticeable weight—a reflection of disordered eating habits.
- Sleep changes. Many PDD patients have trouble falling and staying asleep, yet wake up early. Some sleep way too much and may have trouble getting up.
- Fatigue. People with PDD have low energy and are chronically tired.
- Low self-esteem. These people are less confident and less proud of themselves.
- Concentration issues. As with other types of depression, attention deficits affect many PDD sufferers.
- A state of stuck. Disappointment and hopelessness can immobilize people in the grip of PDD. They may feel as though they’ve wasted their lives or failed to live up to expectations.
Intermittent major depressive episodes may occur and subside back to the lower-grade symptoms of PDD. Unfortunately, the symptoms of Persistent Depressive Disorder tend to last longer and resist treatment more than Major Depressive Disorder. The main difference between PDD and MDD is the time; PDD lasts much longer.
Persistent Depressive Disorder can masquerade as hormonal imbalances, drug side effects, or a metabolic disorder. Also, simple lab tests can rule out whether something physical is causing the depression. Expect your doctor to order these before making a final diagnosis of PDD.
Treating Persistent Depressive Disorder
If a therapy works for one depressive disorder, chances are it will work for another. That’s why the prevailing plan for treating PDD covers antidepressant medication, psychotherapy, or—most powerfully—some combination thereof.
The medication piece
Clinicians primarily rely on two classes of antidepressants to combat PDD: SSRIs and SNRIs. Both drugs block the neurotransmitter serotonin, a mood-regulating chemical found in abundance throughout the central nervous system (among many other body parts). The “N” in SNRI adds norepinephrine, a stress hormone, to the antidepressant’s targets.
Celexa (citalopram), Luvox (fluvoxamine), Paxil (paroxetine), Prozac (fluoxetine) and Zoloft (sertraline) are brands of SSRIs.
Effexor (venlafaxine) and Cymbalta (duloxetine) are brands of SNRIs.
The therapy piece
Antidepressants enable healing to begin. Talk therapy unpacks why you hurt in the first place and how best to get better. Best practices include interpersonal therapy, which focuses on the relationship and social issues contributing to depression, and Cognitive Behavioral Therapy (CBT), which aims to retrain negative thoughts and emotions.
Managing Persistent Depressive Disorder
See the family doctor
Because they know you best, consider consulting your primary care physician (PCP) about your depression symptoms. They might start with the PHQ-9 or a similar screening tool that measures depression severity. From there, PCPs can order lab tests, make the diagnosis or offer a second opinion, then treat or refer as needed.
Give treatment time
Antidepressants need several weeks to begin their work. The doctor may gradually increase the dose over that period until the patient either shows signs of improvement or reaches the maximum dose with no effect. Some patients need to try several different medications to find the one that works best for them.
Learn to love exercise
According to a review of 23 randomized controlled trials, exercise most likely improves symptoms of depression. No triathlon necessary, either: activities such as walking, jogging, dancing and yoga can help the body fight pain and stress, build self-esteem, and improve sleep.
Seek, don’t hide
Seclusion and loneliness only deepen depression. Friends don’t let friends withdraw from the world. Find a support group (even online forums qualify).
Expect the moon
Know that PDD is an illness that waxes and wanes, even during treatment. Trust that recovery is possible.