INSOMNIA.

What are the causes of Insomnia?

Often, people think of insomnia as just something in its own right (primary insomnia that often starts in childhood)  whereas insomnia often has a cause (secondary insomnia).

So let’s look at secondary insomnia.

An “easy” one is too much caffeine. It’s surprising how much better people sleep without lots of caffeine, and the less the better; as a coffee drinker, though, I’d be realistic and suggest 2 cups of fresh coffee per morning (last cup by 1-2pm) is OK. Alcohol also lessens sleep quality.

Insomnia may be linked with depression, anxiety, hypomania (excessive energy) and other psychological problems. But is may not be easy to know which came first – the mood disorder or the insomnia – because insomnia will cause a low mood.

A recent 7 year longitudinal study found that people who reported insomnia at the beginning of the study were more likely to report depression down the track. Another important finding is that insomnia may be a precursor to relapse of depression when there is a history of previous depression.

Sleep quality commonly reduces around the menopause because of both hot flushes and the effects of hormonal changes on the sleep cycle.

Physical causes may be obvious such as pain from arthritis, getting up at night to pass urine more than a couple of times,  hot flushes or night sweats and coughing. Although these seem obvious enough, it’s suprising how often people don’t associate their arthritis pain or urinary frequency with insomnia.

Two important and common causes of insomnia are sleep apnoea and movement disorders. Sleep apnoea is something most people have heard of nowadays, and often people have large neck diameters, snore, their partner may notice they stop breathing at night for a few seconds, and people affected are excessively tired in the day time. Though most people with sleep apnoea will report that they are sleeping well, some may wake someone in the middle of the night and find it difficult to go back to sleep. Sleep apnoea is diagnosed and confirmed on a sleep study.

An important and commonly overlooked cause are restless legs syndrome and periodic limb movement disorder.

Restless legs syndrome (RLS) occurs in 5 to 10% of people and occurs whilst the person is awake. The condition is diagnosed clinically with an urge to move that is  relieved by moving around. The symptoms occur at rest – for example, in the evenings and before going to sleep.

On the other hand, Periodic limb movement disorder (PLMD) causes involuntary leg movements during sleep. This condition is formally diagnosed on a “sleep study” and requires  a series of 4 or more consecutive leg movements 5 to 90 seconds apart.

It’s important to consider underlying causes of both RLS and PMLD before considering medication.