How common is depression and suicide?

Depression is common. According to Lonnqvist (2000) "every year more than one million people commit suicide, accounting for 1 to 2 per cent of total global mortality. It is the fifth highest cause of years of life lost in the developed world".

Suicide is also becoming increasingly common. The same author notes that "According to World Health Organization statistics the annual world-wide incidence of completed suicide was 16 per 100,000 persons in 1995. This means that globally 1 per 6000 persons commits suicide every year." Lonnqvist goes on to note that "the long term trend in suicide mortality has been increasing." He lists nineteen European countries as having rates above the mean for the region, including all the Baltic Republics, The Russian Federation, the Ukraine, Austria, Belarus, the Czech Republic, Switzerland, Finland, France, Belgium, and Bulgaria. The lowest suicide rates in Europe, at below 10 per 100,000, he reports to be in 13 countries which include Greece, The United Kingdom, Spain, Portugal, Albania, Ireland, Italy and the Netherlands. He further notes that outside of the European Region suicide mortality has been exceptionally high in Sri Lanka (above 40 per 100,000) and is also high (over 16 per 100,000) in Japan. Rates are described as moderate (10 - 16 per 100,000) in China, Canada, Australia, Cuba, New Zealand, Singapore, Mauritius, Uruguay and the United States. "Everywhere, the male suicide rate is two to four times higher than the female rate: China is the only exception with a very high female suicide rate."

More often than not suicide is a symptom of depression. In 1998, in Australia, 2683 people were reported to have died as a result of suicide, making it the leading cause of death in this particular country from external causes for all age groups

Is depression becoming more common?

It is difficult to determine whether or not the incidence of depression is increasing. This is because it is now more acceptable for people to seek treatment; therefore, more people are coming forward complaining of it. Also, the diagnosis is being made more frequently by better-informed doctors and other healthcare workers.

The World Health Organization has recently conducted a study that suggests depression is indeed becoming more common. This study measured the effect that various disorders have in terms of human suffering. The study estimated also that by 2020 major depression will be second only to heart disease as a cause of disability.

Is depressive illness more frequent in certain age groups

Certain age groups experience depression more often than others. The symptoms experienced also differ across age groups. For instance, children experience more frequent symptoms of separation anxiety, complain more of physical symptoms and demonstrate increased behavioral disturbance when they are depressed.

As one progresses through childhood into adolescence and adulthood, depressive illness occurs most commonly between the ages of 15 and 44. At any one time, it is estimated that between 0.4% and 2.5% of children (equal numbers of boys and girls), and between 0.4% and 8.3% of adolescents (twice as many females as males) are depressed.

Depression is also very common in the elderly though it is not necessarily a part of aging. The majority of elderly people do not suffer depressive illness. However, if an older person does develop depression it is likely to be more severe than in younger age groups. It may be made worse by physical illness and losses such as death of a spouse.

Does gender affect depression?

Women do seem to be more likely to become depressed than men. The lifetime risk of developing a depressive illness is thought to be 12%-26% for women and 4%-12% for men. This means that depression is about twice as common in women.
The reasons for this are not fully understood though many factors might be important.

• Women tend to seek treatment for 'psychological' problems more frequently than men, who are often less comfortable about seeking treatment (thus resulting in misleading statistics).
• Women are at increased risk of becoming depressed during pregnancy and are especially at risk during the first year after childbirth.
• Women tend to mull over their problems whilst men tend to use activity as a distraction which may result in a higher rate of depression in women.
• An (unproven) theory is that women internalize their feelings and blame themselves for perceived problems, leading to depression, whereas men seem to be more likely to blame others, leading to anger.
• Proposed differences in personality style between the sexes may have an effect.
• Female hormones, estrogen in particular, affect the brain during growth and development, and maturity, and this may affect susceptibility to depression. It has been suggested that the cyclical nature of sex-hormone production in women (associated with the menstrual cycle) may in part explain the increased rate of depression in females. When estrogen levels are low, women may be more likely to develop depression as a consequence.

Although the symptoms of depression are basically the same for men and women, a depressed man seems to be more likely to appear as discouraged, irritable or angry. He may also tend to try to hide his depression by using alcohol or other drugs for relief, or by putting all of his energy into work. Women tend to have more frequent episodes of depression; they also report more symptoms than men do, but when symptom severity is rated by a clinician, men and women both tend to score at the same level.

Do people in certain occupations experience depression more often?

Much work has been undertaken to study possible relationships between occupation and mental health problems. Findings to date suggest that certain types of work are associated with different risks of becoming depressed.

The 'psychosocial work environment' has been found to be a significant factor in determining the likelihood that a person will become depressed. Studies in this area suggest depressive symptoms are more likely to develop in those who work in jobs that have:

• higher levels of psychological demand;
• lower levels of flexibility in decision-making;
• low levels of social and emotional support; and
• longer work hours.

People in professional and managerial occupations tend to have healthier scores on tests of depression than those working in occupations involving the operation of machines or transportation equipment.