Seasonal affective disorder has a lot in common with some other illnesses like RSI or ME in that it tends to polarise medical opinion.
In one corner are the enthusiasts who bang the SAD drum because they feel it’s a woefully neglected and poorly managed area. And in the other are the cynics who say this is another manufactured illness for patients to latch onto, the media to trumpet, and purveyors of ‘treatment’ to exploit.
Who's right?
The real situation lies somewhere between these two extremes. But all the hot air rather gets in the way of the facts.
In this case, the facts aren't great. For example, one recent and authoritative review of light therapy for SAD found that, of all the research published between 1975 and 2003, only about one in ten papers were of sufficient quality to be take seriously.
Why? Various reasons. One being that, when you assess the effect of any treatment properly, you should compare it with a placebo – a ‘dummy treatment’. That’s tricky when you’re dealing with light boxes for SAD.
What exactly is SAD?
The main reason why most of the research should be viewed warily is that definitions of SAD vary and are used somewhat flexibly. This isn’t surprising when you see how complex the bible of psychiatric diagnosis classification (‘The Diagnostic and Statistical Manual of Mental Disorders 4th Edition’, aka DSM IV) makes the subject.
First, it does not view SAD as a diagnosis in its own right. Instead, it’s viewed as a sub category of mood disorder.
To qualify you have to satisfy the following criteria...
There must be a relationship between the onset of depression and a particular time of year
Depressive symptoms must disappear at some other time of the year
These onsets and remissions must have occurred at these times for at least the last 2 years
Seasonal depressives episodes must outnumber non-seasonal depressive episodes over the person’s lifetime
Even after all that you have to be careful that it’s the seasons rather than some other ‘seasonal’ trigger, like employment patterns or term time.
Confused yet?
Not surprising. No wonder people can’t be arsed to do it all by the book. Instead, they’ll retreat back into their own corner and either point out that it has an interesting geographical distribution (most common where seasons are distinct), has been recognised for over 20 years and seems to respond to light therapy.
Or they’ll say, look, we all feel a bit pissed off in winter, that if it does exist, why should it be viewed as an ‘illness’, and if it is an illness, why should it be seen as any different to standard depression?
Ah, the light box. Of course. The trouble is, that seems to work for non seasonal depression, too.
