Abstract
Introduction In the UK, approximately 1.5 million and 30,000 people are estimated to have Obstructive Sleep Apnoea (OSA) or narcolepsy, respectively, with far fewer diagnosed. We used routinely collected National Health Service data to describe diagnosed prevalence, stratified by demographic characteristics in England.
Methods We used primary care data from the Clinical Practice Research Datalink (CPRD) to construct a study population comprising people registered in contributing practices between 02/01/1998 and 29/03/2021, and eligible for linkage to Hospital Episode Statistics (HES) and area-based data. OSA and narcolepsy cases were determined from the first coded primary care or HES record. We estimated prevalence rates directly standardised to calendar year-specific populations, and the number of diagnosed people in 2019. Using prevalence data from 2019, we then used log binomial regression models to estimate prevalence ratios for demographic covariates.
Results Our study population of 37,861,596 people included 272,293 and 6,985 prevalent cases of OSA and narcolepsy, respectively. Estimated age and sex standardised 2019 prevalence rates in England were 1.4% and 0.020% for OSA and narcolepsy, respectively, scaling up to 621,832 (618,652–625,012) and 11,324 (10,894–11,753) people nationwide. Prevalence rates increased over time. In 2019, OSA prevalence rates were highest in men aged 55 to <75. Following adjustment for age and sex, OSA prevalence rates were highest in the North-East, urban communities, areas of higher deprivation and among White and Black people (figure 1). Narcolepsy prevalence steadily increased from childhood to middle age; it was most common among females, black people and in rural areas and lowest in South-Asians/Other ethnic groups and in the least and conversely most deprived areas (figure 2).
Discussion Prevalent diagnosed cases of OSA and narcolepsy are lower than expected, with differences between demographic groups potentially reflecting variation in risk factors, access to specialist sleep centres, and socio-economic consequences of sleep disorders.
