Prakash loves to sleep and looks forward to retiring to bed every day. But for the last few weeks, he has not been feeling refreshed even after a long night’s sleep. Prakash is tired, lethargic and sleepy through the day. He has started falling asleep while sitting, travelling or in the middle of conversations. Over the last few days, he has also been getting up multiple times at night, without an apparent reason. Prakash has started to gain weight and feels disinterested in his hobbies.

Sleep is a stressbuster for most of us. When things get difficult, we all like to “sleep it off”. Not to mention, a sound quality and quantity of night-time sleep is necessary for us to remain healthy.

But what if sleep becomes a concern? Excessive daytime sleepiness (EDS) is persistent sleepiness and lack of energy during the day, even after adequate or prolonged night-time sleep. Twenty per cent of people worldwide experience EDS, according to the National Sleep Foundation. This is different from hypersomnia, when the amount a person sleeps in total during a day is generally more.

In both cases the person is compelled to nap multiple times during the day, constantly fighting off strong urges to sleep even during driving, working, eating and conversing. Like Prakash, many feel tired and lethargic even after they have rested well at night.

Excessive daytime sleepiness has important health implications. Research shows its link with obesity, depression and diabetes. Often, it is a vicious cycle of a sedentary lifestyle and increased risk of diabetes, physical inactivity, high calorie consumption, weight gain, sleep disturbances and daytime sleepiness — which in turn lead to fatigue, loss of motivation, low mood and further immobility and weight gain. An individual is soon within the clutches of depression and obesity, which increase the risk of obstructive sleep apnea (OSA).

OSA, a serious sleep-related breathing disorder, is one of the common reasons for excessive daytime sleepiness. It happens when the upper airway is recurrently obstructed leading to incomplete or absent breathing during sleep.

Most individuals with OSA are unaware they have it. A bed partner or family member may observe a person snoring or appear to stop breathing, gasp or choke while sleeping. OSA may go undetected for decades altogether with the person suffering from headaches, fatigue, daytime sleepiness, reduced performance at work, brain-fog, memory loss and difficulties in multi-tasking.

OSA is commonly associated with depression, anxiety, body pains, reduced libido, flatulence and indigestion, increased frequency of urination and heavy night-time sweats. One of the most common reasons for OSA is obesity (especially sudden weight gain) with more deposition of buccal fat (fat around face and neck). Advanced age, tonsillitis in children, hypothyroidism, long-term snoring, carbohydrate-predominant diet and alcohol abuse are other risk factors. If untreated, OSA can seriously impact a person’s lifestyle, profession and has serious effects on the heart and nervous system.

EDS can also be due to depression, especially in younger people. There are certain “atypical signs” that involve over-eating, high carbohydrate craving and excessive sleep.

Other conditions that can lead to EDS are idiopathic hypersomnia and narcolepsy. While in the first illness, a person has disturbances in consciousness and excessive sleep throughout the day, narcolepsy is a rare neurological disorder in which a person has “sleep paralysis” (also known as cataplexy). These attacks may be triggered by strong emotions and there is a sudden loss of posture, buckling of knees and falling off to sleep. The person may wake up soon after.

EDS is common and neglected by patients, families and physicians alike. Daytime sleepiness, especially in situations such as driving, travelling or swimming — can lead to serious accidents. It can affect thinking, memory and behaviour — and serve as a forerunner of dementia. Dreamlike experiences and hallucinations follow EDS if long-standing.

EDS can be treated. It depends on the cause and a comprehensive evaluation is necessary that involves sleep studies (like a polysomnography). Conditions like depression need medications and counselling while OSA needs an automated machine to regulate breathing called CPAP during sleep. Narcolepsy and other conditions are difficult to treat.

Lifestyle changes form the major bulk of treatment. Work-life balance, exercises, yoga, dietary modifications and social bonding go a long way in minimising the risks of obesity and depression.

So if you, or someone you are close to, is having uncontrolled daytime naps, gaining weight, feeling low and fatigued and snoring more (or a sudden increase) — it’s time to seek professional help.

The writer is a consultant psychiatrist based in Calcutta