Seasonal mood variations are related to light

Winter blues can be cured with medication, bright light treatment, regular exercise, and a sunny holiday in the south

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By Johanna Mannila
     
      Last Thursday marked the autumnal equinox, when the day and night are approximately equally long. In other words, sunrise and sunset are closest to being exactly 12 hours apart at every location on the Earth.
      After the September equinox, nights are longer than days in the northern hemisphere.
     
On the day of the equinox, the sun is located directly overhead at the Equator, crossing over the Equator from the northern hemisphere to the southern.
      The autumnal equinox also marks the start of a period of darkness also known as "polar night" (kaamos in Finnish) at the North Pole.
      When the evenings become darker and days become shorter, many people experience serious mood changes. It is a well-known fact that seasonal mood variations are related to the amount of light: a lack of light causes decreased vitality.
     
Many Finns suffer from some kind of reaction caused by the encroaching darkness, while the number of people with symptoms of severe seasonal affective disorder (SAD) is actually quite small.
      Typical of people suffering from SAD is that they have normal mental health during light seasons.
      In the Duodecim handbook for physicians, psychiatrist Matti Huttunen estimates that only about one per cent of Finns suffer from actual seasonal affective disorder, while some 10 to 30 per cent of the population are experiencing minor mood changes on an annual basis.
     
In less severe cases, sufferers do not have any actual depression. They experience milder symptoms, a condition that is also known as sub-syndromal SAD.
      Such symptoms include fatigue, excessive drowsiness, and weight gain.
     
In order to alleviate their depressive symptoms, people are advised to use bright light treatment in the autumn and winter, while another good method is taking regular exercise.
      One week in the south would be the third useful strategy.
      The symptoms of seasonal affective disorder may consist of depression and loss of energy, reports psychiatrist Marjaana Tölli from Oulu.
     
The first symptoms can be expected in October, while for many SAD sufferers the difficult period may last all the way from November to January. Relief can be expected in February or March.
      Winter depression is more common among the over 30-year-olds than among younger people.
      "However, many of my young patients do experience depressive symptoms as well", notes Tölli, who works for the Finnish Student Health Service.
      If the depressive symptoms are very strong, one should seek medical treatment, as the cause of the symptoms could be some other reason than the period of darkness, Tölli points out.
     
Serotonin reuptake inhibitors (SRIs) are typically used in the treatment of mood changes such as seasonal affective disorder.
      The Social Insurance Institution of Finland (KELA) keeps records on the use of such drugs, and over the period from October through December the use of SRIs appears to increase slightly, estimates Hanna Koskinen from the Research Department of KELA.
     
At gyms and fitness centres, winter depression is a well-known phenomenon, as exercise is one of the methods to alleviate the symptoms of many sufferers, says Managing Director Jyrki Kankkunen from the Motivus fitness centre.
      "The effects of the polar night can be seen here particularly in November, when clients do not have the energy to get up and come to our 7 a.m. classes, even though in October those early morning sessions are always full", Kankkunen notes.
     
Helsingin Sanomat / First published in print 23.9.2010


Previously in HS International Edition:
  Psychiatrist tackles demons of Arctic winter darkness (3.1.2006)

See also:
  ”Winter depression is a disorder of the internal clock” (8.12.2009)

Links:
  Seasonal Affective Disorder (Wikipedia)
  Serotonin reuptake inhibitor (Wikipedia)
  Kaamos/Polar Night
  Equinox (Wikipedia)

JOHANNA MANNILA / Helsingin Sanomat
johanna.mannila@hs.fi