Tuesday, December 3, 2013

Depression Among Alberta Youth

In previous postings, I've described the results of surveys that have generally failed to show an "epidemic" of depression. This is in spite of the fact that one frequently hears concerns that the incidence or prevalence of depression may be increasing. Alberta health has conducted an analysis looking at hospitalization for depression among Alberta youth, and there seems to be an increase since 2010, see attached graphic from the report. This may reflect a change in health care services rather than depression per se. For example, it could be a bad thing: failure or inaccessibility of outpatient services, leading to depression. Or, it could be a good thing: people who need and could benefit from hospitalization being hospitalized. Alberta Health makes a lot of such information available at their interactive website . .

Tuesday, October 22, 2013

Evolution (revolution?) in peer review

The world of publishing in the health sciences has been undergoing major changes. The reason for these changes, at its core, is the revolution in IT. The dominance of paper journals, published and mailed to subscribers is not longer "a given." There are many open access journals now in which the main method of communication is through a web-page, the costs are paid by the authors (usually by the grant that funded the study) and the results are freely available to everybody, either through that Journal's website, or through publicly accessible repositories such as PubMed Central. What is the next step? This may involve an opening up of these repositories to post-publication comment and assessment by a broad readership. PubMed is taking steps in this direction, as discussed in a recent blog entry by Dr. J. Coyne. If successful, this may lead to a democratization of the post-publication dialogue (which previously occurred through a limited number of letters to the editors) that surrounds important papers.

Wednesday, September 18, 2013

Latest information on the prevalence of major depression in Canada

In 2012, Statistics Canada conducted a national mental health survey. This is the second such survey to be conducted in Canada. The first was conducted in 2002. On September 18th, 2013 they released a "Health at a Glance" paper to summarize the results. With respect to the condition of interest to this blog, the prevalence of major depression is reported as stable since 2002 at 5%. A link to the paper can be found here. On the one hand, this is good news, since it does not confirm fears that there is an epidemic of depression in Canada. This is not surprising, see this paper on secular trends. However, it it a cause for concern that the prevalence is not decreasing, despite presumably improving awareness, mental health literacy and access to treatment.

Risk of depression: the past predicts the future

In recent posts, I have noted recent attempts to develop algorithms capable of predicting recurrences in major depression. My colleague, Dr. Jian Li Wang, has been working on developing such algorithms and his work extends similar work done previously by the PredictD study group. However, these algorithms are complex and can be difficult to apply. Dr. Andrew Bulloch, at the University of Calgary has recently shown (link to article synopsis here) that a very simple rule can work quite well. Using Canadian epidemiological data, he has shown that the number of prior episodes is a good predictor and that the risk of future episodes has a linear relationship to the number of past episodes. While this is not surprising, the strength of association is very strong and this may be a strong and simple predictive rule.

Thursday, August 22, 2013

Management of Depression in Primary Care

Most episodes of major depression that are treated at all are treated in primary care. However, making management of depression work well in this setting is a difficult challenge. An innovative approach to the problem has been used in British Columbia under the auspices of their Practice Support Program. A description of the approach has recently been published in the Permanent Journal, and may be found here. This is a brief course, designed for primary care physicians, for implementing basic CBT strategies in a way that is realistic in their setting and doesn't need specialized personnel such as the "depression case managers" often seen in the US-developed approaches. It involves practice and skill building and incorporates a set of materials - most of these materials are available on-line such as Dan Bilsker's antidepressant skills workbook.

Tuesday, July 9, 2013

Calculating one's personal depression risk

A lot of epidemiological research involves estimating the average risk of depression in groups of people characterized by different risk factors etc. A different challenge is to estimate or predict the risk in a specific person - a goal that is more difficult but in some ways more useful (for example, in supporting individual treatment decisions). Dr. Jian Li Wang at the University of Calgary has developed one of the first ever personal depression risk calculators. Anyone can use it. A brief description of the work and a link to the calculator may be found here.

Wednesday, June 26, 2013

Antidepressant Wars / Depression is REALLY hard to treat

One of the areas of controversy that emerged in recent years were claims that antidepressants didn't work very well, or not at all. These assertions were mostly based on analyses of unpublished data. These suggested that positive trials were more likely to be published and therefore that the effects of these treatments had perhaps been exaggerated. However, meta-analyses of the controlled trials were consistent in showing modest efficacy for the medications. A part of the politics of this development in the literature, according to a recent blog post by Dr. James Coyne, is that the results were seized upon by an 'anti-psychiatry' crowd including those with a professional interest in advocating for non-pharmacological treatments. For this reason, a recent meta-analysis was conducted of placebo controlled trials of psychotherapy for depression - those that used the same type of control used in pharmaceutical trials, a "sugar pill" control. These trials show similarly weak effects. Please see the detailed discussion in Dr. Coyne's blog, here, for more a more detailed discussion. Politics aside, my view is that these result emphasize something that clinicians who treat depression and people that suffer from it already know. This condition is hard to treat - there is rarely an easy answer and management is very often a long-term proposition. I don't think it helps for researchers and advocates to divide themselves into camps and to try to beat each other up in "antidepressant wars." We are going to need to seek slow and incremental progress through clinical AND health service advancement and reform if we are to make substantial progress against this condition.

Wednesday, May 29, 2013

Predicting Your Risk of Depression

Dr. Jian Li Wang, at the University of Calgary, has developed algorithms that are intended to predict an individuals risk of depression. The development of these algorithms was a technically demanding task that used data collected from thousands of people in Canadian and US studies. However, the algorithm itself is not difficult to do - it has now been placed on a web page: that can be linked to here. The web page guides you through a series of questions and once you are done will tell you what your risk of getting depressed is.

Tuesday, May 7, 2013

Tensions rising around the release of DSM-5

In a much discussed blog posting, Dr. Thomas Insel, the Director of the US NIMH has publicly critcized the upcoming (in about a week) release of DSM-5. The updated manual will be released at the American Psychiatric Association's Annual Meeting in San Francisco. This kind of public correspondence tends to attract attention, probably because it seems like a public fight. However, the discussion, e.g. see this article, really seems to reflect a longstanding dissatisfaction with the performace of DSM-IV and perhaps annoyance that DSM-5 will not bring psychiatry "into alignment" with the rest of medicine by adopting more "biological" disease definitions. For me, it is hard to identify very much that is new in this debate. The revolution in social and cognitive neuroscience would, on the one hand, seem to be softening the distinctions between biological, psychological and social perspectives while on the other hand proponents for the primacy of one of these perspectives continue to fight the old battles on the sidelines. DSM seems to be a kind of lightning rod for this - viewed either as a psychosocially oriented "fluffy" system, sadly divorced from the kind of biological reality that would allow psychiatry be taken more seriously (like cancer!), or alternatively as a kind of powerful tool of the "biomedical" way of thinking. I tend to view it as a simplistic, but (somewhat) useful, approach to rough categorization and communication. Not to be taken too seriously and certainly not to be taken as a recipe for making clinical decisions, but also our most solid link to our empirical evidence-base and therefore not to be dismissed for reasons of dogma or philosophy.

Tuesday, April 2, 2013

Physical Activity and Depression

There has been a lot of debate about whether physical activity is an effective treatment for depression. The question is not an easy one to answer since exercise involves several different components - one aspect is behavioral activation (a part of the B in CBT), which is expected to lead to more favorable outcomes in depression. However, the aerobic aspects of physical activity may have favorable effects on neuroplasticity (combating some of the negative effects of depression) and my combat certain symptoms such as the fatigue that can be associated with physical deconditioning. In a recent study, we sought to take a broader view than that of treatment effectiveness and looked at whether participation in physically active recreational activities would offset some of the decline in quality of life that is seen in people struggling with depression. We looked at this question using longitudinal data from the National Population Health Survey and the findings were positive. Physical exercise offset much of the decline in quality of life that was seen in depressed persons. The full text of the paper is available here.

Sunday, March 31, 2013

Canadian "Heat Maps" Looking at the Impact of Major Depression

One of the interactive tools produced by the Global Burden of Disease project is "head map" which produces a colour coded ranking of the impact of various causes of disease burden. If you link to this tool - you can select "high income north america" and then remove the USA in order to obtain a country-specific "heat map" for Canada. Use the drop-down menu where you see "GBD Regions" as a default, then click "add or remove location" to the right of this menu if you want to remove the US column. In order to look at different aspects of disease burden you can select Year of Life Lost (where MDD doesn't count since suicide and risk factor related, e.g. cardiovascular, deaths are accounted for differently) or Years Lived with Disability, where MDD is near the top, or Disability Adjusted Life Years (which combines the two categories of burden). You can look at any age/sex group of interest to you (using the appropriate drop-down boxes) and and also have the option of looking at 1990 or 2010 heat maps (using the drop-down menu on the far right-hand side of the screen). This link will take you to the tool.

Monday, March 25, 2013

Screening - A "Fault-line" in the Mental Health Literature

Screening often seems like an obvious solution to health problems. In mental health there is a strong view that much morbidity is undetected - providing an even more compelling intuitive appeal to screening. However, intuitive appeal is a two edged sword because it allows people to overlook some of the actual challenges and problems that accompany screening. This has resulted in some highly polarized debates with entrenched positions and even a degree of hostility. In keeping with Haedt's concept of a righteous mind one suspects that people tend to adopt one side of this debate instinctively, or according to some unarticulated moral compass. I heard Jonathan Haedt interviewed on CBC on March 22nd, 2013 and I've read his book as well, various of the "morality modules" that he describes seems to factor into this debate. Screening proponents often describe screening opponents as uncaring and disloyal to the cause of mental health whereas screening opponents often accuse screening proponents of having a malfeasant agenda - medicalization specifically. Fortunately, there are a set of scientific rules and principles that help to determine the real impact of screening, and as such the debate can be informed by evidence and methodology, all in the (hopefully) wide open sphere of scientific discourse. James Coyne, a prominent psychologist has engaged fully in this debate in a series of articles and a book - and he now contributes to a blog associated with PLoS Medicine called "Mind the Brain". The blog includes some very detailed critiques of screening studies. This makes for interesting reading for those interested in these issues.

Saturday, March 9, 2013

Is Mental Illness a Bigger Problem than Cancer?

In a previous post, I provided a link to a burden-of-disease study recently conducted in Ontario. These studies try to examine conditions that contribute to premature mortality and also to impaired functioning by looking at parameters designed for this purpose (e.g. the Global Burden of Disease Study, see another recent post, uses Disability Adjusted Life Years (DALYs) to account for years lived with disability and premature mortality due to different diseases. The importance of mental illness is seen clearly in such studies since people often develop such illnesses early in their life and the illnesses often persist for many years and has a sustained impact. The Ontario study found that in terms of disease burden (this study didn't use DALYs, but used a related approach) the effect of common mental illnesses was greater than all cancers! A summary has been presented on the CBC website.

Tuesday, March 5, 2013

Websites and Books in the Treatment of Depression

There has been increasing interest in elements of treatment for depression that don't seem like "heavy duty" interventions. This largely results from the ascendancy of cognitive-behavioral treatments, many of which are highly structured - a person can read about them, learn how to employ them and practice them without a therapist present. A Canadian example is one being developed at the University of Saskatchewan for post-partum depression, see news coverage here. The most famous example is the Australian MoodGym program, which is freely available to anyone that wants to try it. Such strategies are often viewed as a low-intensity treatment for very mild episodes - but recent research suggests that they also help in more severe episodes. The evidence is summarized in a paper in the British Medical Journal, which is summarized here.

Saturday, March 2, 2013

New Opportunity to Explore the Impact of Major Depression in Canada

The burden of depression in a country like Canada varies across different age and gender groups, consistent with the epidemiology of the condition (more common in woman than men, and especially common compared to most medical conditions in the younger age groups). There is a major international initiative called the Global Burden of Disease Study that quantifies the impact of most major medical conditions (including Major Depressive Disorder) based on the amount of disability that they cause and the amount of contribution to premature mortality that they make. The results of this project were recently published in a series of papers in the Lancet. However, if you don't want to read these papers, you can examine the ranking of various conditions in an easy to use interactive visualization, by following this link. At the top, select "North America, High Income" where you see "Global" as a default for estimates that should apply to Canada, then you can select an age and sex group and examine the disease burden (what they call DALYs) rankings. Major Depressive Disorder is always near the top.

Thursday, February 14, 2013

The Case for Investing in Mental Health in Canada

The field of mental disorder epidemiology (in its modern form) is a few decades old now, and is beginning to move in increasingly sophisticated directions. One of these is the idea of forecasting the burden of mental disorders, as this will unfold in upcoming decades. A sophisticated effort at accomplishing this was recent carried out in Canada, with support of the Mental Health Commission of Canada. With respect to major ("clinical") depression the finding was that the burden of this condition will increase. This is not due to increasing risk of becoming depressed, but rather due to population growth. The Commission has now posted this report - so that the results are accessible to everyone. A link to the report, and associated materials (which includes a brief summary) may be found here.

Tuesday, January 22, 2013

I am not the only one that thinks "Blue Monday" is a hoax.

This ridiculous attempt at pseudoscience is getting a rough ride, and it is well deserved. Some health reporters are able to see through this, e.g. at CTV. Other bloggers have also been critical, for example, here. Hopefully, this concept will just disappear over time.

Monday, January 21, 2013

The "Blue Monday" hoax

A strange phenomenon seems to be gaining people's attention - the idea that a day in the middle of January is the gloomiest day of the year. Here is an example of a newspaper article about this. The identification of this date is purportedly based on a calculation - which on the surface seems completely bogus. The parameter includes equations such as "weather" and "need for action" and "debt" - things that are not directly measurable and certainly things that one suspects cannot be added or multiplied together to identify a date. There appears to be no discussion anywhere about whatever units would factor into these calculations, nor any theoretical or empirical validation of this equation. As has been pointed out by others (e.g. click here), this appears to be a pseudoscientific hoax that has really taken off. A summary of silly press releases is even available.

Wednesday, January 16, 2013

Diathesis-Stress Models of Major Depression Epidemiology

Several of the postings in this blog have been concerned with the limitations of the current diagnostic conception of major depression. The concerns expressed are not idiosyncratic and have been expressed by many others. The main problems arise from the need (when creating a diagnostic definition, which is a named, or nominal, diagnostic category) to apply some sort of yes/no distinction to emotional states - which are by nature fluid, variable and non-discrete. In DSM, a threshold-based approach is applied whereby people having lots of symptoms, for a long-time and in association with problems (e.g. distress, dysfunction) are considered to have a major depressive episode. There is obvious clinical value to being able to make a diagnosis, but there is a troublesome arbitrariness to imposing a nominal categorization onto what is quite clearly a dimension of experience.

A question that I've had for a long time is whether an alternative conception could be developed, so I've begun attempting to work on this problem. The approach that I've taken is a "diathesis-stress" model approach, which treats each person as having a diathesis level (vulnerability) and as being exposed at any point in time to a stress level, and depressive symptoms are seen as arising from an interaction between diathesis and stress. This week, a description of this work has been published in BMC Psychiatry. A link to the paper may be found here....

The paper has links to some models, which were set up using the free software NetLogo - and are available to anyone that might want to play with them through links contained in the references in the paper (35, 36 and 37).  The first model, which you can link to here...

...illustrates how the model works - a person is simulated by a yellow triangle, which moves over a landscape characterized by different levels of stress (represented by shaded coloring on the model interface), as the "agent" encounters higher levels of stress, there is an interaction between their stress and diathesis, which results in emergence of some level of depressive symptoms. Lots of detail about this and more sophisticated models are available in the paper.