Mental disorders and their impact on work ability

It is common to experience psychological symptoms that come and go, such as sleep disturbances, low mood, anxiety or feelings of hopelessness. In mental disorders, the psychological symptoms are long lasting and have an impact on the person’s functional capacity, interpersonal relations and work ability. This page features a summary of the most common mental disorders affecting working-age people and their impact on work ability.

Find out more about these mental disorders

  1. Depressive episode
  2. Burnout
  3. Anxiety Disorder
  4. Substance use disorder
  5. Bipolar disorder
  6. Personality disorders
  7. Psychosis

Depressive episode

We may all feel depressed or experience other depression-related symptoms every now and then. Clinical depression, however, is a condition diagnosed by a doctor, in which symptoms last longer and significantly affect the person’s functional capacity. Depressive episode is a common illness. Every year, 5–7% of all Finns suffer from it.

Depressive episode can occur for a variety of reasons, including genetic and acquired biological vulnerability, personality traits that make the person more vulnerable to depression and different triggers, such as life events. With the right treatment that is started early enough, most people with depressive episode can make a full recovery.

The symptoms of depressive episode persist for an uninterrupted period of at least two weeks and have a significant impact on the person’s daily life.

To be diagnosed with depressive episode, you must have at least four of the symptoms listed below: 

  • low mood  
  • not getting any enjoyment out of life  
  • exceptional fatigue  
  • low self-esteem 
  • feeling guilt-ridden  
  • having repeated thoughts of death or suicidal thoughts  
  • difficulty concentrating 
  • moving or speaking more slowly than usual or restlessness (psychomotor retardation or agitation) 
  • disturbed sleep and 
  • changes in appetite.

At their severest, the symptoms may involve losing touch with reality and having self-destructive thoughts or plans.

The treatments used for depressive episode are psychotherapy, medication and neuromodulation treatments, such as ECT, direct current stimulation or magnetic stimulation.

Read below about the impact of depressive episode on work ability.

  1. Depression not only affects your mood, it also affects your ability to process information. Difficulties related to memory and learning new things are common. Most people with depression can however continue to work without long periods of sick leave.

    Whether a patient with depressive episode needs to be absent from work and for how long is affected by

    • the person’s functional capacity  
    • the requirements of the work  
    • the workplace’s ability to provide support measures or work arrangements

    The impact of depressive episode on work ability also depends on the severity of the illness:

    • In mild depression, sick leave is usually not necessary.  
    • In moderate depression, the sufficiency of the person’s remaining functional capacity depends on the work’s requirements and whether it is possible to make arrangements that help the person continue at work.  
    • In severe and psychotic depression, the remaining functional capacity is usually not sufficient to meet any work requirements. 


Burnout is a disorder that develops as a result of prolonged work stress. It is characterised by exhaustion, cynicism and reduced commitment to work. Stress in itself is not harmful, as long as it is possible to recover from it properly. Work-related stress is a human being’s attempt to adapt to strain. In burnout, this adaptation no longer takes place and sufficient recovery becomes impossible. The state of stress is prolonged and leads to burnout.

Stress is typically caused by the requirements of work, such as an excessive amount of work, conflicting or ambiguous roles or targets, lack of opportunities to influence one’s work and lack of social support, perceived unfairness and uncertainty.

Stress can also be caused by the employee’s personal traits, such as the demands they place on themselves or their work and a profound sense of duty. Other sources of stress can be the workplace’s insufficient or harmful means for managing stress, such as not taking breaks at work and continuously working long hours.

Burnout is not classified as an illness. However, burnout and its symptoms are associated with a risk of developing depression, sleep disorders, substance use disorders and stress-related somatic conditions, among other things.

Read below about the impact of burnout on work ability.

  1. The impacts of burnout on work ability manifest, for example, as a tiredness that cannot be rested away, a tendency to withdraw from social interaction, and concentration and memory difficulties.

    The initial treatment of burnout often requires some sort of break from work, for example by taking holidays earlier or using time accumulated in the work time bank. If burnout is accompanied by more severe symptoms, such as depression or prolonged periods of poor sleep, the occupational health physician can evaluate whether sick leave is required.

    Because burnout develops in the interaction of the employee and the work, supporting work ability always requires both work accommodation and changes in the employee’s work habits.

Anxiety disorder

In many situations, anxiety is an appropriate response to potential threats or uncertainty. Anxiety disorder, however, is a condition diagnosed by a doctor. It involves strong, long-lasting symptoms that impair the person’s ability to function both psychologically and socially. Anxiety disorders affect 1–2% of the Finnish population. Anxiety disorders are illnesses that develop due to a variety of biological, psychological and social factors.

Anxiety disorders are characterised by an exceptionally strong sense of threat and anxiety, whether episodic or continuous, which the person may try to control through avoidance behaviour. The symptoms also often include physical symptoms, such as heart palpitations, shortness of breath or trembling.

Anxiety disorders, such as the fear of public spaces, panic disorder, fear of social situations and generalised anxiety disorder (GDA), affect the person’s functional capacity and deteriorate their quality of life. They can be alleviated with appropriate treatment. Treatments include psychotherapy, medication or the combination of both.

Read below about the impact of anxiety disorders on work ability.

  1. In most cases, mild anxiety symptoms do not significantly impair the person’s work ability. Severe, incapacitating anxiety disorders, however, can significantly affect work performance.

    As a rule, anxiety disorders can be treated and they do not cause longer-term disability or a risk of disability, at least when not accompanied by other conditions.

    With anxiety disorders, the person’s work ability can be supported by appropriate work accommodation. If the person continues working despite their symptoms, it can support their recovery.

Substance use disorder

In the condition of substance use disorder a person’s use of drugs or alcohol harms their health and/or leads to social problems. Substance use disorders are accompanied by increased tolerance and withdrawal symptoms. The use of alcohol and drugs in itself can cause or be accompanied by various psychological symptoms. These include, for example, mood swings, anxiety, sleep disorders and depression. Treatments should primarily be targeted at the substance use disorder.

It is also possible that a person has a severe psychiatric illness, such as bipolar disorder, and a severe substance use disorder. In that case, both disorders must be treated at the same time.

Read below about the impact of a substance use disorder on work ability.

  1. Signs of a substance use disorder at the workplace can include a change in work performance, withdrawal or short, repeated absences. The person may also be under the influence of alcohol or drugs at the workplace. As a rule, alcohol dependence, intoxication or the use of illegal drugs is not grounds for disability benefits.

    The supervisor should follow the workplace’s drug and alcohol policy in dealing with suspected substance abuse.

Bipolar disorder

Bipolar disorder is a long-term mental disorder that is characterised by unusual mood swings. It involves episodes of depression, hypomania and mania or mixed illness episodes, and periods with few or no symptoms. Mania means a stage where a person is hyperactive, energetic and restless, talks a lot and the need of sleep is decreased. The person does not recognise their condition themselves, and in the manic phase, they may make decisions that lead to problems.

Bipolar disorder is usually diagnosed during late adolescence , but it can develop at any age. The incidence of bipolar disorder is around 1% of people.

Read below about the impact of bipolar disorder on work ability.

  1. Bipolar disorder may be accompanied by difficulty in processing information, such as remembering and learning new things. This should be taken into account when evaluating the person’s work ability.

    Most people with bipolar disorder receive sickness allowance or cash rehabilitation benefit at some point in their working life. Patients with a good treatment balance are able to work or participate in vocational rehabilitation. Due to the illness, however, it is recommended that the work is regular daytime work and that the stress levels remain reasonable.

    The severity of the current illness phase impacts on whether sick leave is required and if so, for how long. Mild depression and hypomania seldom cause disability, whereas in moderate depression, the nature of the work and the motivation determine whether a sick leave is necessary. Hypomania can seemingly even improve work performance, but this will be at the expense of the person’s resources, which will dwindle. All patients with mania and psychotic depression and almost all patients with severe depression are unable to work.

    Whether a person needs to be absent from work and for how long is also affected by  

    • the person’s functional capacity 
    • the requirements of the work 
    • the workplace’s ability to carry out necessary support measures or work arrangements.

Personality disorders

Personality disorders are relatively common. According to estimates, 5–10% of adults are affected by various personality disorders. Personality disorders result from a variety of genetic and embryonic factors, copying the behaviour of parents and various childhood experiences and traumas.

Personality disorders are essentially characterised by a stubbornly rigid way of behaving or experiencing things, which occurs at a young age and causes suffering to the person or is otherwise harmful to them. In different personality disorders, the issues may be related to the individual’s way of observing or interpreting their own or other people’s feelings and thoughts, the intensity or instability of emotional expressions, proneness to impulsive behaviour or difficulties in interaction.

Read below about the impact of personality disorders on work ability.

  1. As a rule, personality disorders do not lead to longer-term disability if they are not accompanied by other conditions. How the symptoms affect work ability depends on the individual and on factors such as the content of the work, the work community and the support provided by the employee’s own social networks. Personality disorders may be accompanied by other disorders, such as depression or anxiety. These parallel disorders often impair the individual’s work ability more than the personality disorder does.


Psychosis is a mental disorder where a person has a reduced sense of reality and has difficulty knowing what is true and what is not. At times, the person struggles to make the distinction between reality and the images inside their head. Hallucinations and delusions are typical psychotic symptoms .

There are different types of psychosis, such as psychosis of unknown origin, reactive psychosis, psychosis related to substance abuse and long-term psychosis, i.e. schizophrenia. Psychosis can be short-term and temporary, and it does not always affect all functionality. Long-term psychosis, however, implies various psychotic illnesses, such as schizophrenia.

Schizophrenia is a psychological illness that starts in young adulthood and comes in many forms. Its worsening can be prevented by identifying and starting treatment as early as possible. The incidence of schizophrenia is around 1.3%, which is some 36% of all cases of psychosis.

Common early signs of schizophrenia include anxiety, depression and impaired functional capacity. The symptoms can last for days or years before the onset of schizophrenia. When the first symptoms develop into a psychosis, the person has strong distortions of thinking and observing, delusions and hallucinations and abnormal emotional expression, such as incoherent speech, strange behaviour or agitation.

The onset of schizophrenia can be understood on the basis of the stress-vulnerability model. According to the model, schizophrenia is triggered in vulnerable persons by internal or external stress. The vulnerability may be genetic, developmental or both.

Read below about the impact of psychosis on work ability.

  1. It is highly possible for a person to recover from short-term psychotic symptoms and regain partial or full work ability. It may also be possible for them to work while having mild symptoms. A long-term psychotic illness, such as schizophrenia, however, often reduces work ability either partially of fully.

    Combining cognitive rehabilitation with occupational rehabilitation or supported employment may improve the chances of patients with schizophrenia finding employment and coping at work. The possibility of vocational rehabilitation or supported employment should always be evaluated in the case of patients with schizophrenia.