Patients with dry eye symptoms sleep more poorly, according to a new study published in The Ocular Surface.
In a population-based study — the first of its kind to examine sleep quality and dry eye in people of European ancestry — researchers looked at 71,761 participants and found that overall, 8.9% of them had dry eye disease. Of these patients, 36.4% had poor sleep quality compared with 24.8% of controls.
The participants were drawn from Lifelines, a multi-disciplinary population-based study focused on the health and health-related behavior of more than 150,000 people living in the north of the Netherlands, with special attention paid to multi-morbidity and complex genetics.
Individuals selected for the dry eye study were between 19 years and 94 years old and 59.4% of them were women.
Participants were asked to complete the self-reported Women’s Health Study dry eye questionnaire, with questions assessing how often their eyes felt dry or irritated, as well as the Pittsburgh Sleep Quality Index, which evaluated their average quality of sleep in the last month.
Patients were also asked about a broad range of disorders, which helped researchers develop a list of 51 factors associated with both dry eye disease and poor sleep quality, including macular degeneration, glaucoma/ocular hypertension, and contact lens use.
A total of 8.9% of the study’s participants had dry eye and poor sleep quality was common, affecting approximately 1 in 4 participants (25.9%). Poor sleep quality was much more prevalent in dry eye patients than in controls (36.4% vs 24.8%, corrected for age and sex, P <.0001). Almost 1 in 2 (44.9%) of patients with highly symptomatic dry eye had poor sleep quality and poor sleep quality particularly increased the risk of having highly symptomatic dry eye.
Researchers found sleep quality was significantly reduced in dry eye patients of all demographics. They also discovered that this pattern was partly explained by coexisting comorbidities, including autoimmune diseases, psychiatric disorders, and chronic pain syndromes. However, after correction for these comorbidities, dry eye was still strongly associated with reduced sleep quality in the Northern European population studied.
The study is the first study to show that the connection between poor sleep quality and dry eye is present in all segments of the population, affecting adults of all ages and sexes. Additionally, patients with highly symptomatic dry eye had a sleep quality comparable to that of patients with sleep apnea syndrome or osteoarthritis. However, it was limited in that researchers were not able to determine causation and did not correct for underlying neurosensory and psychological factors.
The direct comparison of the reduced quality of sleep in participants with highly symptomatic dry eye to chronic conditions that cause poor sleep quality may help increase awareness of dry eye disease as a serious disorder affecting many aspects of life.
Magno M, Utheim T, Snieder H, Hammond C, Vehof J. The relationship between dry eye and sleep quality. Published online January 6, 2021. Ocul Surf doi:10.1016/j.jtos.2020.12.009