Fact Sheet N°
MENTAL AND NEUROLOGICAL DISORDERS
Twenty-five per cent of individuals develop one or more mental or behavioural disorders at some stage in life, in both developed and developing countries. The following disorders can now be diagnosed reliably and accurately as the most common physical disorders; some can be prevented, all can be successfully managed and treated.
Depression is a common mental disorder characterized by sadness, loss of interest in activities and by decreased energy. Depression is differentiated from normal mood changes by the extent of its severity, the symptoms and the duration of the disorder. Suicide remains one of the common and often unavoidable outcomes of depression. If depressive episodes alternate with exaggerated elation or irritability they are known as bipolar disorder. Depressive disorders and schizophrenia are responsible for 60% of all suicides. The causes of depression can vary. Psychosocial factors, such as adverse living conditions, can influence the onset and persistence of depressive episodes. Genetic and biological factors can also play a part.
Prevalence: An estimated 121 million people currently suffer from depression. An estimated 5.8% of men and 9.5% of women will experience a depressive episode in any given year. These figures can, however, vary across different populations.
Treatment: The first-line treatment for most people with depression consists of antidepressant medication, psychotherapy or a combination of both. Anti-depressants are effective across the full range of severity of major depressive episodes. Other effective interventions include setting up supportive network systems for vulnerable individuals, families and groups. The evidence regarding prevention of depression is less conclusive, only a few isolated studies show that interventions proposed for the prevention of depression are effective.
Schizophrenia is a severe disorder that typically begins in late adolescence or early adulthood. It is characterized by profound disruptions in thinking, affecting language, perception, and a sense of self. It often includes psychotic experiences such as hearing voices or delusions. It can impair functioning through the loss of an acquired capability to earn one’s own livelihood or the disruption of studies.
Prevalence: Around 24 million people worldwide suffer from schizophrenia. The disorder is found equally in men and women. Women tend to develop it later in life, and also tend to have a better course and outcome after treatment.
Treatment: Primary prevention of schizophrenia is not possible. However, recent research has focused on developing ways of detecting those suffering from schizophrenia in the very early stages. This increases the chance of early treatment, diminishing the risk of recurrence or serious residual damage.
Treatment of schizophrenia has three main components:
With modern drug advances and care, almost half of sufferers can expect a full recovery. However, in the remaining cases, it can follow a chronic or recurrent course with residual symptoms and serious limitations in daily activities.
Alzheimer’s disease is a degenerative brain syndrome characterized by a progressive decline in memory, thinking, comprehension, calculation, language, learning capacity and judgement. It is important, however, to differentiate the symptoms of Alzheimer’s disease from normal age-related decline in cognitive functions which is more gradual and leads to much milder disability.
There is currently no cure for Alzheimer’s disease. The goals of care are to:
Psychosocial interventions, including education, support, counselling and respite care, are extremely important in Alzheimer’s disease, both for patients and family caregivers. Some medicines have demonstrated usefulness in ameliorating cognitive dysfunction and improving attention, as well as reducing delusions.
Epilepsy is the most common of brain disorders. It is characterized by repeated seizures, or "fits", which range from the shortest lapse in attention to severe, frequent convulsions. They can occur several times a day to once every few months. The seizures are caused by bursts of excessive electrical activity in the brain.
Prevalence: An estimated 50 million people of all ages around the world are affected by epilepsy. Figures indicate that more than 80% of individuals with epilepsy live in the developing world. Effective actions for the prevention of epilepsy are:
Epilepsy therapy aims to prevent seizures and to reintegrate sufferers into community life. Up to 70% of people newly diagnosed with epilepsy can be seizure-free if treated with antiepileptic drugs. Although in most countries the cost of treatment can be as low as $5 per patient per year, the vast majority of sufferers remain untreated. In Africa, 80% of sufferers receive no treatment.
Mental retardation is a condition of arrested or incomplete development of the mind characterized by impairment of skills and overall intelligence in areas such as cognition, language, and motor and social abilities. Also referred to as intellectual disability or handicap, mental retardation can occur with or without any other physical or mental disorders. In addition to genetic factors, injuries at birth and brain infections, a common cause of mental retardation is iodine deficiency, which is the single largest cause of preventable brain damage and severe mental retardation.
Prevalence: It is estimated that the overall prevalence of mental retardation is between 1% and 3%. It is more common in developing countries because of higher incidence of injuries and deprivation of oxygen at birth and early childhood brain infections, all of which cause retardation.
Mental retardation can be prevented. Actions to prevent retardation include:
SUBSTANCE ABUSE DISORDERS
There are a number of disorders resulting from the use of psychoactive substances including alcohol, opioids such as opium or heroin, cannabinoids such as marijuana, sedatives and hypnotics, cocaine, other stimulants, hallucinogens, tobacco and volatile solvents. The conditions include acute intoxication, harmful use, dependence and psychotic disorders. Tobacco and alcohol are the substances which are used most widely across the globe and which pose the most serious public health consequences.
Prevalence: Today, one in three adults or 1.2 billion people use tobacco. By 2025, the number is expected to rise to more than 1.6 billion. Tobacco was estimated to account for 4 million annual deaths by 1998. This is expected to rise to 8.4 million deaths by 2020.
There are an estimated 70 million people who have alcohol use disorders, including harmful use and dependence – 78% of whom remain untreated. The rate of alcohol use disorder for men is 2.8% and for women 0.5 %. An estimated 5 million people worldwide inject illicit drugs – there is a high prevalence of HIV infection among injecting drug users, making it a major public health concern.
Goals of therapy: To reduce illness, disability and death due to the use of psychoactive substances and to help patients lead a drug-free life. Strategies include:
DISORDERS OF CHILDHOOD AND ADOLESCENCE
Mental and behavioural disorders are common during childhood and adolescence. An estimated 10-20% of children have one or more mental or behavioural problems. Many disorders commonly found amongst adults (eg. depression) can begin during childhood. There are two broad categories specific to childhood and adolescence:
Treatment: Child and adolescent disorders require a continuum of care over time linking settings such as families, schools, hospitals and out-patient facilities.
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