Ethnicity and socioeconomic status predict initial continuous positive airway pressure compliance in New Zealand adults with obstructive sleep apnoea.

BACKGROUND

Understanding factors that contribute to low continuous positive airway pressure (CPAP) compliance will lead to improvements in the long-term outcome of patients with obstructive sleep apnoea (OSA) syndrome. Both cultural and socioeconomic factors are likely to be important but have not been systematically studied.

AIM

To examine the effect of ethnicity and socioeconomic status on initial CPAP usage for people with OSA in New Zealand.

METHODS

We retrospectively collected demographic, clinical and CPAP treatment-related data on patients undergoing a 1-month CPAP trial for a 10-month period. We compared objectively measured CPAP usage (by anova) with self-identified ethnicity; levels of socioeconomic deprivation (NZDep06 index), Epworth Sleepiness Scale (ESS) and Apnoea-Hypopnoea Index (AHI).

RESULTS

A total of 214 patients with a mean age of 52.7 (± 11.8) years, mean AHI 57.3 (± 35.8) events per hour and mean ESS 13 (± 5.58)/24 made up the cohort. CPAP usage which averaged 5.13 ± 2.34 h per night was significantly lower in patients of non-European ethnicity (P = 0.019 univariate) and remained significant after socioeconomic status was added to the model (P = 0.048). Patients living in the most socioeconomically deprived areas showed significantly lower compliance with CPAP on univariate analysis (P = 0.024, NZDep06 scores 1&2, average 5.3 per night compared to score NZDep06 scores 9&10, average 4.3 h per night), but this effect was no longer significant once ethnicity was added to the model (P = 0.28).

CONCLUSION

CPAP usage in New Zealand is affected by both ethnicity and level of socioeconomic deprivation. We recommend further research to unravel specific cultural and socioeconomic reasons for the variance reported.