One thing millions crave but don’t get enough of is sleep. And the one thing that millions don’t want at all but find themselves grappling with is depression. A new study conducted by researchers in the UK has found a clear link between sleep and depression. “Sleep and depression are closely linked. About three-quarters of people suffering depression have symptoms of insomnia. Deranged sleep wake cycles exacerbate depressive symptoms. Depression can disrupt the body’s circadian rhythms leading to irregular sleep wake cycles,” says Dr. Aparna Ramakrishnan, psychiatry consultant at Kokilaben Dhirubhai Ambani Hospital in Mumbai.
While it is widely believed that sleep and depression have a bidirectional relationship, the latest research debunks that theory. The study published in the journal Translational Psychiatry in October shows that prolonged periods of lack of sleep, less than five hours a night specifically, can lead to a higher risk of developing depression. The study collected data from two sample groups of roughly 6,000 people each, with an average age of 65 years, enrolled in an English Longitudinal Study of Ageing.
One sample group was used to determine the role of baseline sleep on depression while the other group was employed to determine the role of baseline depression on suboptimal sleep. The study showed that common genetic markers for short sleep play an important role in the incidence of depression and the new findings show that people genetically predisposed to short-sleep are more likely to experience depression. However, they also found that people who are more genetically predisposed to depression are not more likely to suffer from sleep problems.
Insufficient sleep disrupts the delicate balance of neurotransmitters in the brain, affecting mood-regulating chemicals like serotonin, explains Dr. Saurabh Mehrotra, associate director for mental health at Vedanta Hospital’s Institute of Neurosciences in Gurugram. “Chronic sleep deprivation can lead to altered brain function and an increased susceptibility to depression due to these imbalances. Additionally, poor sleep creates difficulty in regulating emotions, leaving people more prone to depression. People with insomnia have a ten-fold higher risk of developing depression than people who get adequate sleep,” he says.
Insomnia, which is difficulty in falling asleep; intermittent awakening; or terminal insomnia (waking up approximately 2 hours prior to normal waking time) remain some of the most common symptoms of depression, explains Ramakrishnan. “Sleep disruptions lead to increased fatigue, low energy, increased sense of anhedonia (lack of interest, enjoyment or pleasure from experiences) and cognitive impairment, and all these aggravate depression. Sleep disturbances can also predict treatment outcome, relapse and recurrence of depression,” warns Ramakrishnan, adding that hypersomnia, which is prolonged sleep and excessive daytime drowsiness, can also be a symptom of depression.
Dr. Shambhavi Jaiman, consultant psychiatrist at the Fortis Memorial Research Institute in Gurugram, emphasises that addressing sleep issues is crucial in treating depression, and improving sleep can lead to better mental health. While all experts agree on the importance of getting enough sleep to ensure good mental health, they don’t quite agree on how much sleep we require.
While Jaiman says a person requires anything between 6-8 hours of sleep, Ramakrishnan feels the range is more like 7-9 hours and Mehrotra puts the sleep requirement between 7-8 hours. However, all of them agree that exactly how much sleep an individual requires could also be outside of these ranges depending on one’s age, health conditions, and individual sleep requirements. “Genetics, stress, lifestyle factors, health issues may also affect an individual’s need for sleep. Some people may feel rested after 6 hours while many require up to 10 hours of quality sleep,” adds Ramakrishnan.
The best way to ensure you are getting enough sleep is to follow good sleep hygiene, say experts. “Establishing a consistent sleep schedule, creating a relaxing bedtime routine, optimising the sleep environment such as keeping the room dark, quiet, and cool, avoiding caffeine and alcohol intake, regular exercise, spending time outdoors, and managing stress through techniques like meditation or yoga can promote healthy sleep patterns,” says Mehrotra.
Another thing to avoid is the scourge of modern life — cell phones and computers — at least one hour before sleep, advises Jaiman, adding that using modern technology to maintain ambient light in your room at night also helps. Apart from bright screens at night, experts are also not a big fan of long day-time naps, which can disrupt your nightly sleep schedule. The ideal nap should be 10-20 minutes only. Finally, if your sleep problems persist, seek medical medical advice to address the underlying issues.
Shrenik Avlani is a writer and editor and the co-author of The Shivfit Way, a book on functional fitness.