03/12/2013 05:46 EDT | Updated 05/12/2013 05:12 EDT

The Trickle-Down Effects of Depression

As a registered clinical psychologist who has assessed and treated many patients over the years, I consider depression to be the costliest elephant in the room. Those with depression feel stigmatized and silenced while the medical, economic and social costs of the illness mount daily.

The statistics should give us all pause --

• 1 in 5 Canadians will suffer a mental illness in his or her lifetime.

• 1.5 million Canadians become depressed every year.

• Anxiety and depression are among the top five reasons for a visit to the doctor.

• Only a third of people with mental illness get the help they need.

When left untreated, depression can lead to more and longer episodes that can have devastating effects on the ability to cope and function. Depression often becomes a chronic health condition that waxes and wanes throughout life, requiring ongoing management.

Having depression heightens the risk of developing a chronic physical problem, such as diabetes, high blood pressure, heart disease, dementia and acute medical problems like stroke. All of these physical disorders, in turn, need management by the same individual whose ability to manage life is already compromised due to poor emotional health.

People who are caregivers for those with mental illness, physical illness and dementia, have an elevated risk of developing depression. Indeed, a 2010 Canadian Institute for Health Information report pointed out that caring for a person with dementia is correlated with increased stress and emotional problems.

Family members are a vital support for our overburdened health system, given that 70 per cent of the responsibility of dementia care falls on these informal caregivers. If these family caregivers fall ill with depression, it adds yet another layer of medical burden on an already stressed healthcare system. Sadly, fully two-thirds of all depressed individuals do not link up with appropriate health services. Who will care for our elders afflicted with dementia if their family caregivers fall down? Who will care for the fallen caregivers?

Make no mistake, there is a ripple effect when someone develops a mental illness -- family, friends and co-workers are all impacted in different ways. People with depression have difficulty coping and functioning with daily life demands. Depression causes relationship disruptions, exacerbates the risk of developing physical disorders, and makes it difficult to study or hold down a job.

Consider these troubling statistics:

• Each day, 500,000 Canadians miss work due to mental illness.

• In Canada, worker absenteeism due to mental illness costs $51 billion in healthcare costs and lost productivity; $34 billion in Ontario alone.

If we combine direct and indirect costs, depression is easily the most expensive health disorder in the world. We also know that having a history of depression doubles one's risk of developing dementia later in life. Dementia is another devastating cognitive disorder and it is the single most expensive illness in terms of direct medical costs.

What can we do to better help those who suffer from depression?

We need an integrated model that de-stigmatizes mental illness and offers information and resources in an accessible way -- where people live, work and play. A recent news story about Canadian tennis star Rebecca Marino giving up the sport she loves because of her battle with depression is a stark reminder of the toll this condition takes on us mentally and physically.

We need to start treating depression more like the chronic disorder it so often becomes (i.e. more like diabetes), rather than the acute disorder our medical system is designed to treat (i.e. treating depression as an isolated incident like a broken leg).

One treatment strategy that I see as very promising and have used with my patients is Cognitive Behavioural Therapy, also referred to as CBT. It is an evidence-based, self-management treatment that helps with mood and coping for people who suffer from depression and anxiety. CBT helps patients recognize maladaptive thinking patterns that tend to trigger anxious and depressed emotions and teaches strategies for developing healthier patterns of thinking. CBT can be used as a solo treatment or in conjunction with medication.

We have much more work to do as a society to help Canadians, young and old, who suffer in the shadows with depression. Thanks to the courage of people like Marino and Canadian Olympian Clara Hughes, we are removing the stigma of mental illness and encouraging others to talk about mental health problems with their loved ones. People must secure the professional help they need so that they can re-engage with life in a satisfying way that provides meaning and positive feelings.

When it comes to depression, silence is the symptom we can least afford.

Mind Your Mood is a series on aging, mood and brain health by Dr. Nasreen Khatri, a registered clinical psychologist and researcher at the Rotman Research Institute at Baycrest Health Sciences in Toronto. Each installment will deal with a different aspect of depression and cognition with a corresponding "elephant in the room" symbol.