What it is
Persistent depressive disorder, once called dysthymia, is a long-lasting form of depression. The low mood is present most days for at least two years in adults (one year in children and adolescents). The symptoms are often less intense than in a major depressive episode, but they never fully go away.
Because it lasts so long, many people stop noticing it as an illness. They tell themselves they are simply pessimistic, weak or “born this way.” Families may come to see the person's low energy and gloom as character. This is one reason it so often goes untreated.
What it can feel like
A grey filter over everything, for years. Low energy, poor sleep or oversleeping, low self-esteem, difficulty concentrating, hopelessness about the future. People often function. They go to work and raise children. But joy is thin and everything costs more effort than it should.
Some people also experience full major depressive episodes on top of the persistent low mood. Clinicians sometimes call this “double depression,” and it is a strong signal to seek treatment.
How common is it
Around 1.5% of adults experience persistent depressive disorder in a given year, and roughly 3% will experience it at some point in life. Because sufferers rarely identify their state as an illness, the real numbers reaching care are far lower.
What causes it
The causes overlap with those of major depression. A tendency runs in families, and long-term stress, early adversity, chronic illness, isolation, and ongoing difficult circumstances can all feed a low mood that settles in and stays. Because it lasts so long, the low mood can start to feel like simply who a person is, which hides the fact that it is a treatable condition rather than a fixed character.
How it is diagnosed and treated
Diagnosis is clinical: a careful history showing low mood most days for two years or more, alongside symptoms like poor appetite or overeating, sleep problems, fatigue, low self-esteem, poor concentration or hopelessness. The clinician will also rule out medical causes and check for episodes of major depression and for past periods of unusually elevated mood.
Treatment mirrors that of major depression, talking therapies (CBT, IPT, behavioural activation) and antidepressants, alone or combined, with one honest caveat: chronic depression typically needs a longer course of treatment than a single depressive episode, and the combination of medication plus therapy outperforms either alone. The most important step is the first one: recognising that years of low mood are not a personality, but a condition that responds to help.
Persistent depression in the African context
Long-lasting low mood is easily missed everywhere, and especially where daily hardship can make a flat, joyless mood seem normal or expected. In many settings a person who keeps working and meeting their duties is assumed to be fine, so years of quiet suffering pass unnoticed and unnamed. Calling it what it is, a treatable condition rather than a personality, is the change that opens the way to help. See also our main depression guide.
Managing it day to day
Alongside treatment, the same daily steps that help depression help here, sustained over the long term.
- Keep a regular routine for sleep, meals, and activity, even when motivation is low.
- Do small, valued activities rather than waiting to feel like it, an approach called behavioural activation.
- Stay connected to people, and treat isolation as something to act against.
- Move your body in small ways, and limit alcohol, which deepens low mood.
- Be patient, since recovery from long-term depression is gradual but real.
Helping someone
If someone you love has lived with low mood for years, your understanding helps.
- Try not to see their low energy and gloom as simply their character, since it may be a treatable condition.
- Encourage them gently toward professional help, and offer to help arrange it. Our find a therapist page can help.
- Be patient and steady, since change is slow, and notice small steps.
- Look after yourself too, since supporting someone over a long time is demanding.
When to seek help
If you cannot remember the last time you felt genuinely well, if low mood has been your normal for a year or more, speak to a professional. Long duration is not a reason to wait; it is the reason to start.
Sources
- American Psychiatric Association. (2022). DSM-5-TR.
- Cuijpers, P., et al. (2010). Psychotherapy for chronic major depression and dysthymia: A meta-analysis. Clinical Psychology Review, 30(1), 51-62.
- Kriston, L., et al. (2014). Efficacy and acceptability of acute treatments for persistent depressive disorder: A network meta-analysis. Depression and Anxiety, 31(8), 621-630.
- Schramm, E., et al. (2020). Review of dysthymia and persistent depressive disorder: History, correlates, and clinical implications. The Lancet Psychiatry, 7(9), 801-812.