The causes of Clinical Depression also referred to as Major Depressive Disorder, or MDD, may come from one or more of three different sources. An MDD sufferer may be genetically predisposed to having a mood disorder. Their depression may stem from the environment or be caused by negative thought patterns.

Studies with twins show if they are identical they are more likely to share depression if one of them already has the condition. A parent with a mood disorder may pass on the likelihood of having depression to their offspring. Even if the child of someone with depression seems to have escaped inheriting it, they may find depression can more easily be triggered by personal life crisis than offspring of parents who don’t suffer from the condition.

Its been discovered that stroke victims, who have brain damage in the frontal lobe region are likely to be depressed. Interestingly, individuals with depression tend to have a reduced frontal lobe, indicating this region of the brain and damage to the area may be a contributing factor.

People who are depressed have raised levels of the stress hormone cortisol, and healthcare professionals may see this as part of the cause. However at the moment depression can’t be diagnosed by cortisol levels.

When it comes to environmental factors there are several considerations to be made. A normal bereavement for example, which presents symptoms of the natural grieving process isn’t usually seen as Clinical Depression. However, major life crisis, disasters, financial worries, and oppression can result in severe depression which requires treatment.

Environmental factors which result in depression may come with one loud bang, or ruminate over long periods of time before full blown Clinical Depression is experienced. Hence a natural disaster, such as a tsunami in which a home and loved ones are lost, may cause instant depression in an individual, whereas financial hardship and a bad relationship may be a long, hard slog, which builds depression.

When healthcare professions talk of thinking patterns in terms of being the cause pf Clinical Depression they don’t mean thinking negative thoughts now and then leads to depression, they mean repetitively having consistent negative thoughts over a long period of time can cause Clinical Depression to occur.

The causes of Clinical Depression are varied, and may stem from biological factors, the environment or thought patterns. However, most people who receive treatment find depression improves and some find it can be cured.

The following is a short film about depression from NIMHgov