How optimism and pessimism influence our sleep

Recent research results show a significant correlation between the basic human attitude of optimism and the quality of sleep.

Optimists sleep better

Recent research results show a significant correlation between the basic human attitude of optimism and the quality of sleep.

The researchers found that optimists tend to sleep better. The study results are based on earlier studies that saw a connection between optimistic thinking and cardiovascular health. The new study was conducted at the University of Illinois under the direction of Dr. Rosalba Hernandez.

Dr. Hernandez's team examined 3,548 participants aged between 32 and 51 from various US states participating in the study "Coronary Artery Risk Development in Young Adults" (CARDIA).

Five-point Likert scale survey conducted

In order to gain an insight into the basic attitude of the persons examined, the researchers asked them to give their opinion on ten statements using a five-point Likert scale. The scale ranged from "strong agreement" to "strong disagreement".

The statements ranged from "I am always optimistic about my future" to "I hardly expect things to go as planned". The survey results ranked from 6 as the most pessimistic case to 30 as the most positive number identified.

Participants reported on their sleep quality in five-years intervals

As part of the CARDIA study, participants reported twice on their sleep quality with an interim period of five years. They discussed their sleep quality and possible signs of insomnia.

Some of the participants also completed the Pittsburgh Sleep Quality Index and the Epworth Daytime Sleepiness Test. They also wore monitors to objectively measure how long the deep sleep phases lasted and how restful their sleep was. In order to establish the link between optimism and sleep quality, the researchers supplemented multivariate regression.

74% lower probability of insomnia in optimists

The study revealed that any increase in the range of standard deviation was associated with a 78% increase in better sleep quality. Participants with higher results slept more often six to nine hours per night and suffered from insomnia up to 74% less frequently.

"The study results showed significant correlations between the basic attitude and self-reported sleep quality. We were able to identify this from a variety of variables such as sociodemographic characteristics, health conditions and symptoms of depression," said Dr. Hernandez.

"The lack of healthy sleep is a major public health problem"

Dr. Hernandez added: "The lack of healthy sleep is a major public health problem. Poor sleep is associated with many conditions. This includes higher risks of obesity, hypertension and total mortality. Dispositional optimism has a striking psychological impact on disease-free survival and better health."

Although the study results are purely empirical, the authors speculate about possible explanation mechanisms. Dr. Hernandez concludes: "Optimists often have a better way of dealing with problems and stressful events. This results in fewer worries and thoughtful considerations when falling asleep and during the sleep cycle".

Hernandez R et al., Behavioral Medicine 2019; doi:10.1080/08964289.2019.1575179