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4 min read<\/p>\n4 min read<\/p>\n
NEARLY ONE IN four cases of depression may fall into this category. A study<\/a> published in the British Journal of Psychiatry identified \u201ccircadian depression,\u201d and people with it have an internal 24-hour clock that\u2019s out of sync with their external environment.<\/p>\n Like really out of sync. We\u2019re not talking about jet lag<\/a>. This is when your body\u2019s internal timing network just can\u2019t regulate your body\u2019s systems.<\/p>\n It’s important to get this out of the way upfront: Circadian depression isn’t in the DSM-5\u2014the \u201cpsychiatry bible\u201d mental health professionals use to make diagnoses. In other words, it’s not an official condition yet. But it\u2019s important to know about. We had mental health experts break it down.<\/p>\n What Is Circadian Depression?<\/p>\n CIRCADIAN DEPRESSION IS a subtype of depression caused by circadian disruption, which is when your body\u2019s circadian rhythm<\/a> doesn’t align with your external environment. People with circadian depression have disrupted sleep-wake cycles, lower levels of daytime activity, low energy, and weight gain<\/a> during depression episodes, according to the study.<\/p>\n People who were classified in the study as having circadian depression were more likely to have severe symptoms of depression, including:<\/p>\n Bipolar-like features such as maniaSuicidal thoughtsPsychological distressPhysical symptoms like pain or fatigueWeight gain during episodes<\/p>\n People with circadian depression also seem to be more likely than those with other forms of depression to have other conditions like ADHD<\/a>, anxiety, bipolar disorder, obesity, or insulin resistance.<\/p>\n What Did the Study Find?<\/p>\n THE STUDY\u2019S RESEARCHERS analyzed clinical and genetic data from more than 10,000 Australians with depression. To determine whether people had the proposed subtype, circadian depression, rather than general depression, they looked at factors like a person’s social jetlag (the mismatch between their internal clock and external schedule), whether they were night owls, how tired they felt in the morning, and whether they experienced excessive daytime sleepiness. They also looked at whether people had poor responses to antidepressant treatment, and people with severe symptoms that were a mix of bipolar disorder, depression, and somatic disorders.<\/p>\n About 23 percent of participants fell into the category of circadian depression. This is more than a label. It\u2019s important to recognize because, as the researchers pointed out, people with circadian depression tend to be less responsive to traditional antidepressant medications. That means treatment tailored to their subtype is especially important.<\/p>\n What Causes Circadian Depression?<\/p>\n A FEW THINGS are happening here. First is people\u2019s sleep schedules getting thrown off, possibly from chronic inflammation and a messed-up metabolism. There is prior evidence<\/a> of a link between circadian rhythm and these two factors (though researchers are still on the fence on what causes what).<\/p>\n \u201cThe body\u2019s internal clock helps coordinate changes in the brain throughout the day,” says Hillary Ammon, PsyD<\/a>, clinical psychologist at the Center for Anxiety and Women\u2019s Emotional Wellness. That includes a feeling of alertness and motivation during conventional waking hours. When the timing is off, these coordinated changes are also affected.<\/p>\n \u201cIncreased tiredness, low motivation, or decreased focus can all be factors that lead to depression and also be traits of depression,\u201d says Ammon. Having an internal clock that’s off schedule also impacts your metabolism and stress hormone cortisol<\/a>.<\/p>\n Increased cortisol release at night can lead to an increase in unease and difficulty sleeping. Changes in metabolism rates can cause weight gain. Weight gain and decreased activity are classic symptoms of depression.<\/p>\n
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