Last week, I posted about the characteristics of depression in the elderly.  I’m now following up with a discussion of the causes of depression in this age group.  What causes depression in the elderly is quite similar to what causes depression at other ages.  In this post I’ll cover two causal factors: biological tendencies and influences from past life events.

Biological Tendencies

Genetic proclivity is an important biological risk factor for depression.  Research suggests that the heritability of depression may be as high as 50%; in other words, genetic factors and non-genetic factors may contribute about equally to the likelihood that depression will occur.  It appears that few cases are the result of single genes; instead, several genes incline a person to depression, and people differ in how many of these genes they inherit.  Even if someone has a strong predisposition towards depression, other factors affect whether that tendency is manifest in actual depressive symptoms.  That’s where the other causal factors—past influences and current stressors—become important.

Influences from the Past

One significant contributor to depression at any age is a history of childhood abuse.  Sexual, physical, and emotional abuse have long term effects, often affecting the entire span of life.  For example, a woman in her 60s whose father would fly into drunken rages still has vivid recollections of these episodes, feeling once again like a helpless child.  These memories are associated with increased feelings of depression.   Troubling events that occurred after childhood, especially those that produced permanent effects, can also result in late-life depression.

Our pasts affect more than just our memories.  They shape our views of ourselves and of the world.  They can lead to what one psychologist calls “early maladaptive schemas”—biased ways of thinking about oneself and others that lead to skewed perceptions or unwise decisions throughout life.  They are like a tax that the past continues to levy throughout life.  Thus, one person may have an incompetence schema, believing that they are unable to handle the ordinary tasks of life unless others help them.  Another might have an abandonment schema, expecting that others won’t continue to provide care and support but will deliberately or unintentionally become unavailable.  Such ways of thinking are resistant to change, and may become more rigid and extreme late in life.  For example, one man with an incompetence schema worked in a low-paying job in which little was required of him.  After he retired at age 69, he became extremely reliant on his wife and asked her for help and direction for even the simplest tasks.  She found his constant requests unbearable and took a part-time job so that she would have time away from him.  Shortly thereafter his mood became depressed.

Another avenue through which the past can instigate depression in the elderly is via a life review.   Older adults are likely to reflect on the lives they have lived and to experience either satisfaction or dissatisfaction as a result.  If one feels content with decisions made and proud of accomplishments, there is a sense of integrity and wholeness.  On the other hand, if one regrets what he or she has done or failed to do, there is emptiness and despair.  That emptiness and despair often takes the form of depression.

The causes of depression covered in this post exert their influence over the course of years.  Some causes are more immediate, though.  Next week I’ll write about those.

Author Bob Ritzema, PhD has more information available at http://beyondhalfway.wordpress.com/