Some mental health conditions are more common than others. Conditions such as depression and anxiety are much more common than psychotic conditions such as schizophrenia and bipolar disorder (manic depression). There are also conditions that relate to someone’s personality which are known as personality disorders. Mental health conditions are defined by the Mental Health Act. Further information on the Mental Health Act can be found in Section 16: Mental Health Act.

Someone can have a mild, moderate or severe mental health condition with a range of symptoms. Someone may have a severe mental health condition but experience good mental health. This could be because they are managing their condition well with medication and therapy. In contrast, someone could have no diagnosed mental health condition but have poor mental health. For example, they might be experiencing a particularly difficult time due to life events such as a bereavement, relationship problems or issues with work.

Symptoms often overlap across several conditions and everyone will experience things differently.

i. Depression and anxiety disorders

Depression and anxiety disorders are the most common conditions. It is normal to experience low mood and anxious feelings from time to time. Someone can develop a mental health condition when these feelings become more severe and affect everyday activities.

Common symptoms of depression:

• experiencing low mood and self esteem
• lack of energy
• feeling hopeless and worthless
• difficulties in concentrating and making decisions
• poor memory

Common symptons of anxiety:

• feeling irritable
• excessive worrying 
• difficulties in sleeping and concentrating
• fear and panic
• physical symptoms such as sweating, heart palpitations, breathlessness and pain.

Post traumatic stress disorder (PTSD) is a type of anxiety disorder. Someone can develop PTSD if they experience a traumatic or frightening event, such as being a victim of a violent crime, being involved in military combat or witnessing a violent attack or death. PTSD causes feelings of intense fear, helplessness and horror. Someone can have panic attacks, nightmares and flashbacks (seeing images or visions of a past event in their mind).

There is the misconception that PTSD most commonly affects veterans. Around 1 in 25 veterans of the Iraq and Afghanistan wars are likely to develop PTSD, similar to that in the general public. However, while the rate of occurrance is similar, the complexity of the disorder tends to be much greater. Furthermore, it often occurs alongside other medical problems such as pain, disability and substance misuse, particularly alcohol misuse (Combat Stress, 2015).

ii. Psychosis

Psychosis is less common. About 1 in 100 people have psychosis (Royal College of Psychiatrists, 2011). It is classed as a 'severe mental illness'. The most common psychotic conditions are schizophrenia and bipolar disorder (manic depression).

The main symptoms of psychosis are hallucinations and delusions.

Hallucinations are experiencing something that isn't really there. This can affect all the senses-sight, smell, taste, touch and sound. Hearing voices is the most common hallucination in schizophrenia. These voices may tell the person to do something, or be critical of the person. This can be very distressing.

Delusions are false beliefs. For example, someone with schizophrenia may think that someone is trying to harm them, or that they are an actor playing out a part in a film. Due to these beliefs, the person may act strangely.

Common symptoms of schizophrenia:

• difficulties in determining what is real or not
• muddled thinking and speech
• difficulty in relating to others
• little motivation
• self neglect and poor hygiene.

Common symptoms of bipolar disorder (manic depression):

• extreme changes in mood, from severe lows (depression) to highs (mania) with regular moods in-between
• symptoms of mania include increased self esteem, talking quickly, racing thoughts, delusions, hallucinations, acting irrationally.

 iii. Personality disorder

Between 10 and 13% of the general population have some form of personality disorder (Girolamo and Dotto, 2000). This includes borderline personality disorder and anti -social personality disorder. 

We all  have individual characteristics called personality traits. These affect the way we think, feel and behave. Someone may be described as having a personality disorder if these characteristics cause regular and long term problems in the way they cope with life, interact with others or how they respond emotionally.

Each type of personality disorder includes specific symptoms. Some typical symptoms are:

• not trusting other people, feeling threatened
• lack of emotion
• extreme fear of rejection, becoming dependent on others
• appearing not to care about other's opinions of them
• reckless and impulsive behaviour
• being overly dramatic and like to be the centre of attention
• perfectionism
• not seeing the bigger picture

Personality disorder is probably the most misunderstood diagnosis in mental health. Personality disorder was included in the definition of mental disorder in the 2007 amendments to the Mental Health Act. But there is still controversy over its inclusion.

In 2003 the National Institute for Mental Health produced guidance, 'Personality Disorder: No longer a diagnosis of exclusion', making it clear that people with personality disorders should receive appropriate care and should not be excluded from services because of their diagnosis.