To investigate clinical characteristics of dry eye disease (DED) patients with a chronic pain syndrome.
Cross-sectional study.
Four hundred twenty-five patients of a tertiary care DED patient cohort in the Netherlands were included. Chronic pain syndromes irritable bowel syndrome, chronic pelvic pain, and fibromyalgia were assessed by questionnaires. Outcome variables were the Ocular Surface Disease Index (OSDI) symptom questionnaire, tear osmolarity, Schirmer test, tear breakup time, conjunctival hyperemia, staining of the cornea and conjunctiva, and amount of mucus. Outcomes were cross-sectionally compared between DED patients with a chronic pain syndrome and those without.
A total of 74 out of 425 DED patients (17%) had at least 1 chronic pain syndrome. The total symptom score was significantly higher in DED patients with a chronic pain syndrome than in those without (45.8 vs 33.8, P < .0005). Moreover, patients with a chronic pain syndrome scored higher on every single subscale of the 12-item OSDI symptom questionnaire. However, ocular signs were similar or even less severe in these patients. Similarly, in 64 DED patients from the population-based cohort TwinsUK, patients with a chronic pain syndrome (n = 24, 38%) had higher subscale and total (34.1 vs 14.4, P = .001) symptom scores.
In DED patients, chronic pain syndromes are common and are associated with increased severity of DED symptoms across all domains of the OSDI, even though objective ocular surface signs are no worse. In clinical practice, more awareness of chronic pain syndromes might help in understanding the discrepancy between signs and symptoms in DED.