Introduction

We all feel sad or lethargic every now and then. And we have all felt down or even desperate at some point in our lives. These phases are a normal part of life, and people usually feel better after a while. That might happen if things change again, for instance. Depression is different. The sadness and negative thoughts last longer and overshadow all other thoughts and actions.

Depression can arise without any stressful events or for no apparent reason. People often feel like they're stuck in a deep, dark hole. They feel cheerless and lack motivation, and might also suffer from extreme self-doubt or feel worthless. This can make it difficult to do everyday things like going to work or studying. Friendships, family and hobbies are often neglected. Many people who have depression don't sleep well.

Depression can also make family and friends feel worried, anxious and helpless. Often they want to help but don't know how. It is not always easy for them to tell whether it's a passing phase or a serious illness.

At a glance

• Depression can lead to things like feeling down, exhaustion, lack of motivation and loss of interest.
• It is one of the most common mental illnesses.
• The risk of developing depression is influenced by your life circumstances and distressful events, as well as your genes.
• The symptoms often go away again after several weeks or months – but they can also come back or become chronic.
• Depression can be treated using psychological approaches and medication.
• The support of family and friends is very important.

Symptoms

People who have depression fall into an emotional black hole for weeks or months. The medical term for a period like that is a major depressive episode. The typical signs are:

• The person feels sad and down. Most things seem to be pointless, and they are hardly interested in anything. It is hard to lift their spirits.
• They have a deep emptiness inside, feel exhausted and emotionally numb, and lack the motivation to do anything.
• And others feel unsettled and suffer from agonizing worries, fears and anxiety.

Depression often causes sleep problems and makes it hard to concentrate. Particularly in older people, depression can also lead to physical symptoms such as weight loss or inexplicable pain.

Depression not only causes listlessness, it can also make people more excitable. For instance, in bipolar depression (manic depressive disorder), people have depressive phases followed by euphoric phases where they lose touch with reality.

Some people also have chronic depression. Then the symptoms last for many years.

Causes and risk factors

The cause of depression is not exactly clear. It is thought that various things play a role. These include biological processes, psychological and social factors, a person’s individual circumstances and particular events in their lives. Here are some examples of things that can make depression more likely and influence the course of the disease:

• Genes: an increased risk of depression if other people in their family have had depression
• Difficult experiences: for instance, abuse or neglect, the end of a relationship or the death of a loved one
• Other mental illnesses such as anxiety disorders, addictions or personality disorders
• Biochemical changes: Your metabolism and hormonal changes can also play a role.
• Physical medical problems such as strokes, heart attacks, cancer or an underactive thyroid.
• Difficult life circumstances: for instance, constant stress, loneliness or low income
• Lack of light: The dark autumn and winter months can lead to depression in some people.

Prevalence

Depression is one of the most common mental health problems. It is estimated that 16 to 20 out of 100 people will have major depressive disorder or persistent depressive disorder at least once in their lives – often already before they turn 30. Women are affected more than men, and it is more common in older people.

Outlook

The course of depression can vary. In some people things get better after a few weeks or months – sometimes even without treatment – and the depression doesn't come back. About half of all people who are treated for depression feel a noticeable improvement in symptoms after about three to six months.

Depression comes back in about half of all people who develop it for the first time.

Many have regular episodes of depression followed by depression-free phases. Other people have depression that lasts a long time, with it getting more and less severe, while some people have persistent symptoms. If it lasts longer than two years it is considered to be chronic depression.

Over half of all people with depression also have other illnesses. Those could include:

• Psychological illnesses like anxiety disorders, addictions, eating disorders and personality disorders.
• Physical illnesses like cardiovascular (heart and blood vessels) diseases, head and back pain, diabetes and infectious diseases, as well as asthma or allergies.

These kinds of illnesses may contribute to the development of depression, but it is also possible that they could be an effect of the depression.

Effects

Depression makes people feel and behave differently than they used to. Many think it's their own fault, and are plagued by self-doubt. They say they have feelings that they can no longer control or cope with. Thoughts of suicide may arise. In most cases they don't actually take that step, but unfortunately that is not always the case.

People often become withdrawn, avoid social contact and hardly leave the house any more. It is also often difficult to go to work. They might start abusing alcohol, medicine or other drugs. All of that can make the depression even worse. It is often only possible to stop this vicious circle with the help of others.

Depression is also not only a burden on the person who has it, but also on their friends and family.

Diagnosis

Some people have such severe depression that they no longer have the energy to get help themselves. Then it's important for their family and friends to offer support and, for instance, to come with them the first time they see a doctor.

To find out whether someone has depression, psychotherapists do two things: They ask about symptoms that could be signs of depression. They also try to rule out other illnesses or health problems that cause similar symptoms. To do so, the doctor might need to perform physical examinations or tests too.

The typical symptoms of depression can be divided up into core (main) symptoms and secondary symptoms. The core symptoms include:

• A low, depressive mood
• Lack of joy and interest in things that used to be important
• Lack of motivation and getting tired quickly, even after minor exertion

The secondary symptoms include:

• Difficulty concentrating and making decisions
• Low self-esteem and self-confidence
• Feelings of guilt
• Inner restlessness
• Hopelessness
• Trouble sleeping
• Loss of appetite
• Suicidal thoughts or suicide attempts

Depression is diagnosed if someone has several core and secondary symptoms over a period of two weeks or longer. Depending on the number, type and severity of symptoms, doctors can categorize depression as mild, moderate or severe, and also distinguish between chronic depression and a major depressive episode.

The therapist asks about any other illnesses the person might have and about how their everyday life is affected by the symptoms. Both of these things play a role in deciding on a treatment.

Prevention

Distressing experiences like a major loss or chronic stress can contribute to the development of depression. Avoiding certain negative influences or learning to deal with them differently can help lower the risk of depression. That can be particularly important for children and teenagers.

The people in your life also play a big role. Having stable relationships lowers the risk of depression.

And getting psychological help or counseling early on can also help to prevent depression if you feel distressed by a difficult situation in your life. For people at high risk of recurring depression, long-term treatment with medication or psychotherapy might be considered for prevention. The two can also be combined.

Treatment

There are various treatment options for depression. The main treatments are psychological treatment and/or medication. There are also other options, including counseling, support groups, psychoeducation, online programs, neurostimulation and exercise therapy. The treatment can be done in an outpatient setting or in a hospital.

Which type of treatment is the most appropriate, where it should take place and how long it lasts will depend on several factors, including

• how severe the person’s depression is,
• what type of depression the person has,
• what the symptoms are,
• what other illnesses the person has,
• how the depression affects their personal circumstances, and
• how their symptoms develop over time.

People can talk to a therapist about the advantages and disadvantages of the possible treatments, as well as what they expect from treatment and any fears they might have.

Rehabilitation

Some people are unable to go to work or care for themselves or others for a long time due to depression. Then rehabilitative care might be an option. It can show you ways to cope better with depression and to manage its symptoms.

Rehabilitation for depression is typically offered for a few weeks at a hospital. In Germany, statutory pensions funds generally cover the costs, but sometimes health insurers pay.

Everyday life

If you have depression, everyday life can become an insurmountable burden that is extremely difficult to cope with. The demands of work, private commitments and even small household chores can become a major effort. Relationships with partners, friends and family often change. Those close to someone with depression usually find it very distressing too. Emotional withdrawal and apathy can lead to arguments, which makes the situation even more difficult for all those involved.

Still: Many who have mental health problems or illnesses turn to their partner, family or friends first. These people are often the first to notice that something is wrong. Their comfort and support is particularly important to those who have depression. But partners, family and friends need help too if the depression is severe. As well as seeking advice from doctors and psychotherapists, they can turn to support groups too.

Active help and support are especially important if there's reason to believe that someone is thinking of killing themselves. It is very important to take any signs seriously and talk to others about it. If that isn't possible in an acute situation, there are various places you can turn to for help. In Germany, these include social-psychiatric services (in German: Sozialpsychiatrische Dienste), crisis support centers and a special crisis helpline (Telefonseelsorge) which is anonymous and available 24 hours a day. You should call for emergency services if someone is in immediate danger (112 in Germany and most European countries, 911 in the United States). It may be necessary to have the person hospitalized against their will.

Further information

In Germany, most people with mental health problems or illnesses turn to their family doctor first when looking for professional help and advice. But you can also contact psychological support services, or the private practices of psychiatrists or psychotherapists. In urgent cases such as an acute risk of suicide, you can contact a practice that offers out-of-hours services, or the drop-in center of a psychiatric hospital.

Sources

• Bundesärztekammer, Kassenärztliche Bundesvereinigung (KBV), Arbeitsgemeinschaft der wissenschaftlichen medizinischen Fachgesellschaften (AWMF). Nationale Versorgungsleitlinie Unipolare Depression. AWMF-Registernr.: nvl-005. 2022.
• Deutsche Gesellschaft für Kinder- und Jugendpsychiatrie, Psychosomatik und Psychotherapie (DGKJP). Behandlung von depressiven Störungen bei Kindern und Jugendlichen (S3-Leitlinie, in Überarbeitung). AWMF-Registernr.: 048-023. 2013.
• Robert Koch-Institut (RKI), Statistisches Bundesamt (Destatis). Depressive Erkrankungen (Gesundheitsberichterstattung des Bundes; Heft 51). Berlin: RKI; 2010.

• IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

  Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. informedhealth.org can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

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