Sleep duration and psychological well-being among New Zealanders.

OBJECTIVE

To identify the prevalence of short and long sleep duration and examine the relationship between sleep duration and psychological well-being among New Zealand adults.

DESIGN

Multiple regression using data from the New Zealand Attitudes Values Study postal questionnaire.

PARTICIPANTS

New Zealand Attitudes Values Study respondents in 2014, 2015, and/or 2016 (Ns =15,820, 13,942, and 21,937).

MEASUREMENTS

Participants were asked, "During the past month, on average, how many hours of actual sleep did you get per night?" They also reported their demographic characteristics, physical and psychological health, and personality traits.

RESULTS

Most New Zealanders reported having optimal sleep duration (7 to <9 hours, 58%), but more than a third reported having short (<7 hours, 37%) and 4.5% reported long sleep duration (≥ 9 hours). Māori and Pacific peoples showed particularly high rates of short sleepers. Compared to optimal sleep, short sleep consistently showed negative relationships with various measures of positive psychological well-being (eg, self-esteem, life satisfaction) independent of a broad range of demographic, health, and personality factors. Long sleep was only associated with an increased likelihood of depression. Personality traits, especially neuroticism, also showed strong associations with psychological well-being.

CONCLUSIONS

The high proportion of short sleepers in New Zealand is a major issue of concern because short sleep showed consistent associations with negative psychological well-being. It is vital to implement sleep awareness campaigns and increase research on the reasons for short sleep among different groups. Given the ethnic disparity in sleep duration, target interventions for Māori and Pacific peoples are particularly crucial.