It’s quite normal to feel a little bummed out when the weather is miserable, but there’s a big difference between the rainy-day blues and seasonal affective disorder (SAD). Sometimes referred to as winter depression, SAD is a clinical condition that resembles major depressive disorder but comes and goes in a seasonal pattern.
While SAD can sometimes strike in spring and summer, it’s much more common for people to experience symptoms in the darker, colder months of the year. The disorder tends to be associated with a severe drop in mood and energy levels that persists until winter is over.
Other symptoms may include irritability, difficulty getting out of bed, a loss of interest in everyday activities, and craving foods that are high in calories and carbohydrates - often leading to weight gain. However, because these symptoms are commonly experienced by sufferers of other mental health conditions, accurately identifying SAD can be tricky and self-diagnosis is not advised.
Individuals who suspect they may have SAD can download the Seasonal Pattern Assessment Questionnaire (SPAQ), which was developed in 1984 and remains the most widely used tool to diagnose the disorder. The brief assessment asks patients to rate their changes in mood and appetite over the course of the year, but is not a definitive indicator of SAD.
Rather, people who score unusually highly on the SPAQ are encouraged to contact a healthcare professional in order to discuss the possibility of a SAD diagnosis. Doctors will usually conduct their own analyses in order to confirm the condition and rule out other overlapping mental health disorders. This process may sometimes involve testing the blood for thyroid hormone levels as well as a complete blood count.
Typically, a person needs to display clearly marked seasonal fluctuations in symptoms that follow the same pattern over multiple years before they are diagnosed with SAD. Those who are confirmed to be suffering from the condition will then be offered a range of treatments.
This often begins with assistance in making positive lifestyle changes, such as getting regular exercise, eating healthily, and spending time outdoors. Light therapy is another common form of treatment for SAD, and involves spending time basking in the light emitted by a type of lamp known as a light box, which is designed to mimic sunlight.
Talking therapies can also help lighten the load of SAD, and patients may even be offered antidepressant medications in some cases.
At present, the exact causes of SAD aren’t fully understood, although it’s likely that a lack of sunlight interferes with key neurotransmitters such as serotonin and melatonin, which regulate mood and sleep respectively. Perhaps unsurprisingly, the condition is more common at higher latitudes, where winters are colder, darker and longer.
However, SAD can affect anyone, no matter where they live, which is why any individual who experiences notable drops in mood as the seasons change is advised to contact a doctor.
The content of this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.
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