Depression: Numbers and Trends

How common is depression?

Depression is one of the most common of all psychological difficulties. For example, take Major Depressive Disorder, just one of the various types of mood problem.

Number of people who are likely to have a Major Depressive Episode in their lifetime:

• 5 to 12 % of men
• 10 to 25% of women

At any one time, how many people are in the midst of a Major Depressive Episode?

• 2 to 3% of men
• 5 to 9% of women

In Canada, about 3 million people will have depression at some point in their lives.

As many as 1.4 million are likely suffering from depression at any one time.

What does depression cost?

The cost of depression to society is immense. The 1999 report of the U.S. Surgeon General on mental health cited a study by Harvard School of Public Health which estimated the cost of various forms of illness to developed market economies using data from 1990.

They used a measure of the years of productivity lost to illness or death, and rank-ordered illnesses by their impact on these societies (essentially Europe, North America, and Japan).

Years of productivity lost, in millions:

• 1. Ischemic heart disease 9.0
• 2. Major depression 6.8
• 3. Cardiovascular disease 5.0
• 4. Alcohol use 4.7
• 5. Road traffic accidents 4.3

Depression is one of the top medical causes of lost productivity in these economies. It is the largest cause of disability of any mental disorder.

In Canada, depression is presently the #2 cause of long-term disability (behind cardiovascular disease and ahead of back injury).

Canada's Business and Economic Roundtable on Mental Health report on depression in the workplace (2000) estimated the costs to the US and Canadian economies at about $60 billion per year. Canada's share of this is approximately $6 billion.

Is the rate of depression rising?

This is difficult to say for certain, due to changes in the definition of depression and in the stigma associated with it.

The consensus of most studies, however, is that:

• Depression is increasing in prevalence in Western countries.
• The age at which people first experience depression on average is becoming younger.
• Recurrent depression is becoming more common among those who suffer depression.

Why the increase? The short answer is that we don't know. A slightly longer answer is that certain risk factors appear to be increasingly common in our culture:

• Inactivity and poor physical condition.
• Poor nutrition.
• An increase in the rate of family breakdown.
• The emphasis on consumer purchases as a way to manage emotion.
• Increased time pressure.
• Reduced social contact in favour of solitary activities (e.g., television, internet).

Doubtless there are other factors as well.

In sum, depression is a remarkably common problem that imposes a great cost on society as a whole.

Despite this fact, fewer healthcare resources are devoted to it than to other health problems that have less impact. All the more reason for people affected by depression to do their best to educate themselves about the condition.

Note: Information on these pages is provided for educational purposes only. It should not be taken as a substitute for care from a qualified healthcare provider.