Persistent Depressive Disorder vs Major Depressive Disorder

Hong-hui Lin
Dec 2, 2025
7 min read

Updated: Dec 5, 2025

We often talk about depression as a sort of catch-all term to describe feeling low, unmotivated, empty, tired, hopeless, helpless… any or all of these feelings and more. But there are actually different types of depression that feel and impact us differently.

Persistent Depressive Disorder (PDD) and Major Depressive Disorder (MDD) are two forms of depression that can affect people in different ways. While both share similar emotional struggles, the difference between MDD and PDD often lies in how long and how deeply these symptoms are experienced.

Distinguishing Symptoms: MDD vs PDD

The primary clinical distinction between MDD vs PDD (dysthymia) lies in their duration and severity, with MDD presenting as acute episodes (feels like a crash or distinct drop in mood) and PDD as chronic, long-lasting low mood.

Symptoms of Major Depressive Disorder (MDD)

Major Depressive Disorder (MDD) is identified when a person experiences:

Persistent low or depressed mood
Loss of interest or pleasure in usual activities (anhedonia)
Feelings of guilt or worthlessness
Low energy or fatigue
Difficulty concentrating
Changes in appetite
Psychomotor retardation or agitation (feeling slowed down or unusually restless)
Sleep disturbances
Suicidal thoughts

According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), a person may be diagnosed with MDD when five or more of these symptoms persist for at least two weeks. One of these should involve either a lasting low mood or a noticeable loss of interest in things that usually bring joy.

These experiences can make it hard to stay present at work, connect with others, or keep up with everyday routines. Clinicians also check that no manic or hypomanic episodes have occurred to ensure an accurate diagnosis .

Symptoms of Persistent Depressive Disorder (PDD)

Persistent Depressive Disorder (PDD), also known as dysthymia, is a longer, lower-grade, persistent form of depression. As described in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), it combines the previous diagnoses of dysthymic disorder and chronic MDD.

This condition is characterised by a lingering sadness or low mood that stays for much of the day and tends to recur almost every day. People can usually function as normal, but feel a sense of a chronic low-grade fog, tiredness, or a sense of disengagement with life that never lifts. For diagnosis in adults, these feelings last for at least two years, while in children and adolescents, they last for a year or more.

PDD symptoms come and go but rarely disappear completely by themselves. People who feel this way may therefore sometimes have thoughts of hopelessness or suicide, and it can make navigating daily life just as difficult as it is for someone with MDD.

Factors Contributing to Depressive Disorders

Depression often develops through a combination of biological, psychological, and social influences that interact over time. People who have faced difficult life events such as loss, trauma, or prolonged stress may be more vulnerable to developing depression.

In many cases, the condition itself can also make daily life harder to manage, creating a cycle where stress and sadness continue to build on each other. Negative thinking can also add weight to these emotions. Focusing too much on what went wrong or replaying self-blaming thoughts can lower motivation and increase feelings of helplessness.

This ongoing inner dialogue not only shapes how a person sees themselves but can also deepen the sense of hopelessness that comes with depression.

There is growing evidence that changes in the brain may play a role in maintaining depressive cycles. Studies suggest that people with depression often show reduced dopamine activity, a neurotransmitter that supports motivation and pleasure, which may explain why even simple daily tasks can start to feel overwhelming or joyless.

Risk Factors Associated with Depressive Disorders

A variety of underlying psychological, social, environmental, and biological factors can shape a person’s vulnerability to depression and influence how it develops or persists over time.

Psychological Factors

Long-term or chronic stress
Low self-worth or negative self-image
Exposure to trauma or emotionally distressing experiences

Social and Environmental Factors

Financial hardship or economic instability
Gender-based discrimination or inequality
Racial discrimination or social exclusion

Biological Factors

Family history or genetic predisposition
Chronic medical conditions or poor physical health
Certain medications that may influence mood

The Effects On Daily Functioning

PDD and MDD often affect daily life in similar ways, touching many areas of a person’s routine, relationships, and overall well-being. For instance, both conditions can cause:

Reduced Intimacy: A lowered interest in physical closeness or affection can lead to emotional distance, even in caring relationships.
Loss of Enjoyment: Activities that once felt meaningful or fun may no longer bring joy, leading to withdrawal from hobbies and social connections.
Emotional Sensitivity: Irritability or sadness may surface more easily, with tears or frustration appearing over things that once felt manageable.
Fatigue and Low Motivation: Constant tiredness can make it difficult to focus, stay productive, or find the energy for daily tasks and self-care.

While both share overlapping symptoms, PDD can sometimes have a stronger impact on daily functioning. This is because its symptoms last for years, gradually affecting a person’s motivation, focus, and sense of connection.

Different Ways to Address MDD and PDD

Managing MDD and PDD often involves a combination of professional support and personal strategies tailored to each individual’s needs.

The Role of Medication

People diagnosed with major depressive or persistent depressive disorder may be prescribed antidepressant medications, including selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), or tricyclic antidepressants to help relieve some of their symptoms and lift their mood. As everyone responds differently to different medications, finding the right medication and dosage is a process that can take time, often requiring a period of trial and error to determine the most suitable option.

Therapeutic Interventions

For those with major or persistent depressive disorder, psychotherapy, particularly cognitive behavioural therapy (CBT), is a common form of therapeutic approach used.

This method can help individuals understand how their thoughts and feelings are connected, and recognise which ones may be unrealistic or overly harsh. By learning to challenge these unhelpful patterns, individuals can begin to shift their responses to difficult emotions and situations.

Other therapeutic options may also be recommended, such as mindfulness-based CBT, insight-oriented or psychodynamic therapy, and interpersonal therapy, depending on the individual’s needs.

Consulting a clinical psychologist in Singapore, or another licensed mental health professional, can help identify which therapeutic approach may be most appropriate for one’s needs and provide ongoing guidance throughout the process.

Self-Management Strategies

Coping skills also play an important role in how one manages MDD and PDD. Because no single factor explains why these conditions develop, part of the process involves learning to accept what you cannot change while focusing on what you can.

Therapy can guide you in developing these coping skills, but it’s equally important to create a personal care routine that supports your emotional well-being, such as:

Having fun
Getting enough restful sleep
Eating nourishing meals
Engaging in meaningful activities
Staying active through regular exercise
Practising yoga
Setting aside time for mindfulness or meditation

Over time, nurturing these habits can help strengthen emotional resilience, giving you the inner strength to face difficult days with greater clarity and control.

Can You Have Both MDD and PDD?

Depression can show up in different ways. For those with PDD, it’s a constant low mood that lingers for years, while for those with MDD, it comes in intense waves. But do these two experiences ever overlap? Can you have two types of depression at the same time?

The answer is yes. You can have both MDD and PDD at the same time. This overlap is commonly referred to as “double depression”.

“Double depression” is not a formal clinical term. Instead, it describes when someone experiences symptoms of two depression diagnoses. In such cases, a person with double depression may carry the constant heaviness, hopelessness, and low self-worth that come with PDD, while also experiencing the deeper emotional lows of MDD when a major episode occurs.

During these episodes, symptoms can intensify, sleep and appetite may change, energy levels drop, and feelings of worthlessness or emptiness can grow stronger. What makes double depression especially challenging is how these persistent and episodic symptoms overlap, leaving little relief in between.

Factors Contributing to Double Depression

Double depression can develop through a combination of genetic and environmental factors. Some individuals may be biologically more prone to depression, while life circumstances can add further emotional strain over time. These experiences often interact, making it harder to recover once low moods take hold.

Some common life experiences that may increase vulnerability include:

Growing up or living under financial pressure
Feeling isolated or lacking emotional support
Going through major life changes or ongoing stress
Experiencing long periods of job loss or instability
Having a history of trauma or difficult relationships
Struggling with substance use or dependency

Steps Toward Better Management of Double Depression

When it comes to double depression, improvements often happen slowly rather than all at once. Response to therapy can depend on many things, including the severity of symptoms, their genetic background, life circumstances, and the kind of therapeutic approach involved.

For this reason, it can take time to find what truly helps. Antidepressant medications may need several weeks to take full effect, and in some cases, adjustments are necessary before the right balance is found.

But with the right combination of self-care, depression counselling, and support from mental health professionals and peers, improvement is possible.

Getting Professional Help

Depression can make even the simplest days feel difficult, but it’s important to remember that help is always available. If you or someone you care about is experiencing persistent depressive disorder, major depressive disorder, or signs of double depression, don’t hesitate to seek professional support.

At The Psychology Atelier, our team of therapists can guide you in managing these challenges and finding a way forward at your own pace. Alongside support for depression, we also offer therapy for anxiety, trauma, and other emotional difficulties to support your overall well-being.