The Winter blues is a complex depressive illness. It is most likely triggered by the lack of sunlight in winter, which affects levels of hormones (melatonin and serotonin) in the part of the brain controlling mood, sleep and appetite – our circadian rhythms.
Symptoms are wide-ranging and can include depression, lack of energy, concentration problems, anxiety, overeating, loss of libido, social and relationship problems and sudden mood changes or periods of hypomania (over-activity) in spring.
SAD diagnosis can usually be made after two to three consecutive winters with the symptoms.
Most research on acupuncture for depression has been carried out in China with Western drugs as comparators. Two recent systematic reviews, both drawing on Western and Chinese data, found that acupuncture was similar in effectiveness to anti-depressant medication and not significantly better than sham acupuncture or waiting list controls. However, they reached very different conclusions, one recommending acupuncture (Zhang 2010) and one stating that the evidence was insufficient (Smith 2010). Major issues to consider in respect of the research evidence are a) how trustworthy are Chinese studies (Ernst 2010), b) how valid are sham controlled trials (Schroer 2010), and c) how relevant to normal practice is the acupuncture provided in trials (Schroer 2010). Notions about acupuncture’s placebo properties (Ernst 2010) can only be speculative, and with little relevance to decisions about patient benefit. Given that acupuncture appears to be at least as effective as existing conventional drugs, without their level of side effects, it should be considered as one of the therapeutic options, alongside the existing repertoire.
In general, acupuncture is believed to stimulate the nervous system and cause the release of neurochemical messenger molecules. The resulting biochemical changes influence the body’s homeostatic mechanisms, thus promoting physical and emotional wellbeing.
Studies indicate that acupuncture can have a specific positive effect on depression by altering the brain’s mood chemistry, increasing production of serotonin (Sprott 1998) and endorphins (Wang 2010). Acupuncture may also benefit depression by acting through other neurochemical pathways, including those involving dopamine (Scott 1997), noradrenaline (Han 1986), cortisol (Han 2004) and neuropeptide Y (Pohl 2002).
Stimulation of certain acupuncture points has been shown to affect areas of the brain that are known to reduce sensitivity to pain and stress, as well as promoting relaxation and deactivating the ‘analytical’ brain which is responsible for anxiety and worry (Hui 2010). Stress-induced changes in behaviour and biochemistry may be reversed (Kim 2009).
Some of the most recent research suggests that depression is associated with dysfunction in the way that parts of the resting brain interact with each other (Broyd 2008); acupuncture has been shown to be capable of changing the ‘default mode network’ (Dhond 2007), but the effect goes beyond that of expectation/placebo (Hui 2010).
Acupuncture can be safely combined with conventional medical treatments such as anti-depressants, helping to reduce their side effects and enhance their beneficial effects (Zhang 2007).