This portfolio of research aims to increase understanding of the sleep habits and sleep health of New Zealand adults, aiming to inform more effective public health approaches and appropriate sleep diagnostic and treatment services. Central to this work are our collaborations with Te Rōpū Rangahau Hauora a Eru Pōmare and the WellSleep Clinic at Otago University Wellington. Follow-up work is in progress analysing the 2013-2014 National Health Survey data, in collaboration with the Ministry of Health (Dr John McCarthy).
The recommended sleep duration for adults aged 26-64 y to maintain health, safety, productivity and well-being is 7-9 h. Among New Zealanders aged 20-59 y, Māori are more likely than Non-Māori to report usual sleep duration longer or shorter than recommended. Higher rates of unemployment, night work, and socioeconomic deprivation among Māori contribute to these differences. Growing evidence suggests that poor sleep may mediate ethnic inequities in other areas of health.
Social jetlag describes the discrepancy in the amount and timing of sleep on scheduled days versus free days. Getting at least 2 hours more sleep on free days indicates that a person is getting insufficient sleep on scheduled days. Among NZ adults aged 20-59 y, 30% of Māori and 23% of non-Māori have insufficient sleep. The difference by ethnicity is partly explained by greater socioeconomic deprivation and more night work among Māori.
In contrast to other aspects of sleep, significant differences have not been found in measures of sleep timing between Māori non-Māori, for example in Horne-Ostberg Morningness/Eveningness scores, or in the estimated population prevalence of advanced and delayed sleep phase syndromes.