Insomnia is on the rise. Each year, an estimated 25% of Americans develop insomnia. Roughly 27% of working women and about 20% of working men experience insomnia. Nearly half of adults over the age of 60 report symptoms of insomnia.
In the United States, lost productivity from insomnia is estimated to cost the economy up to $63 billion per year. In addition, insomniacs are far more likely to experience depression and get into car accidents. As many as 30% of drug overdoses involve medications prescribed for insomnia.
In a first-of-its-kind study, researchers at the Netherlands Institute for Neuroscience proposed using personality traits and life histories to divide insomniacs into categories that may prove helpful when assigning treatments.
For the study, lead researcher Tessa Blanken and her team analyzed life history details and personality traits of more than 2,200 patients diagnosed with insomnia between the years 2010 and 2016.
The team’s results were published in 2019 in Lancet Psychiatry.
Blanken divided patients into five categories based on what she calls “non-sleep characteristics.” These characteristics include distress, anxiety, depression, and childhood trauma.
“We thought we might look into different characteristics that inform the context in which insomnia develops and persists,” writes Blanken. “The characteristics we focused on have been shown to be rooted in brain function and structure, and therefore are stable over time.”
Cat 1: Highly Distressed
This group is marked by high levels of distress and tends to experience a lot of energy/anxiety right before bedtime. Compared to the other groups, Cat 1 insomniacs were the most likely to suffer from depression.
Cat 2: Moderately Distressed
Cat 2 insomniacs also experience high levels of distress and report feeling energetic/anxious before bedtime but do not exhibit the same lack of general happiness as the first group.
Compared to the other groups, Cat 2 insomniacs were the most likely to suffer insomnia due to stress. Blanken believes Cat 2 insomniacs may suffer from psychophysiological insomnia - a condition in which the fear of being unable to sleep prevents sleep.
Cat 3: Highly Apathetic
Cat 3 insomniacs are defined by overwhelmingly low levels of positivity in addition to general distress. Interestingly, they are the least likely to suffer depression.
“The third type has a really clear diminished positive affect and a really low subjective happiness,” writes Blanken.
Cat 4: Highly Reactive
This group reports far lower levels of general distress than the others and is believed to suffer insomnia due to life events such as financial trouble, relationship difficulties, and childhood trauma.
This group tends to develop insomnia after the age of 40.
Cat 5: Highly Unmotivated
Cat 5 insomniacs also experience sleeplessness as a result of life events, although patients in this group reported fewer negative experiences during childhood and did not exhibit Cat 4 insomniacs’ acute response to stressors.
Cat 5 insomniacs are marked by low levels of “behavioral activation” (motivation) and tend to develop insomnia later in life.
By dividing insomniacs into categories, Blanken was able to study how each group responded to various forms of treatment. For example, patients in Cat 2 responded favorably to cognitive behavioral therapy while patients in Cat 4 did not.
Patients in categories 2 and 3 experienced better sleep after taking benzodiazopene, with the latter group also reporting significant fatigue during the day.
“This is really only the beginning,” says Blanken. “Ultimately, I would hope that it would help people by optimizing treatment.”