Sjögren’s Patients Perceive Dry Eye Discomfort as Less Severe
Dry eye disease is more severe in people with primary Sjögren’s syndrome than in other patients, but their perception of eye discomfort may be altered, according to a recent study.
“Clinicians should be aware that [Sjögren’s] patients may complain less of their discomfort” while having a particularly severe case of dry eye disease, researchers noted.
The study, “Different perception of dry eye symptoms between patients with and without primary Sjogren’s syndrome,” was published in the journal Scientific Reports.
Dry eye disease (DED) is a common condition in which eyes are insufficiently lubricated, leading to symptoms like burning sensations, itching, light sensitivity, blurred vision, and eye fatigue. The underlying causes of DED are numerous.
In Sjögren’s, the glands that produce tears are mistakenly attacked by the immune system, leading to DED symptoms.
Previous studies have shown that patients with the same clinical assessment of DED severity may have entirely different perceptions of discomfort. The variable underlying causes of DED and/or individual differences in sensory nerve function could be involved in these different responses.
In the study, researchers evaluated the perception of DED symptoms by 276 people, including 55 patients with primary Sjögren’s and 221 people without the disease.
Perceived eye discomfort was evaluated using the ocular surface disease index questionnaire (OSDI), where higher scores indicate more discomfort.
People without Sjögren’s had higher average OSDI scores compared with Sjögren’s patients (43.6 vs. 36.3). However, in objective clinical measures of DED, the patients showed overall worse disease severity compared with other DED patients.
Specifically, the researchers found that those with Sjögren’s had higher ocular staining scores, indicating more severe eye damage. Reduced tear production, as measured by the Schirmer test, and more corneal surface erosion, or damage to the eye’s outer layer, were also observed. Altogether, these parameters indicated Sjögren’s patients had more severe DED.
Among patients with the same level of corneal erosion, those without Sjögren’s perceived their symptoms to be more severe than the patients with the disease.
Similarly, in participants who perceived their symptoms to be severe (OSDI score of 33 or higher), Sjögren’s patients had worse clinical severity, despite OSDI scores being similar to those of non-Sjögren’s patients.
The sensitivity of the nerves in the cornea was near normal in both groups, and no other clinical parameters were associated with OSDI scores.
Altogether, these results suggest that while Sjögren’s patients have clinically worse DED, they do not perceive their symptoms to be as severe as do non-Sjögren’s patients.
As a possible explanation for this, the team proposed that stress relief signaling pathways may be activated in Sjögren’s patients to counter the effects of prolonged and severe eye damage and inflammation.
“Chronic and prolonged inflammatory stimulation in the ocular surface may paradoxically induce discomfort-relieving signals in [Sjögren’s],” the researchers wrote.
These compensatory processes may depend on the duration of DED, which should be evaluated in future studies, they said.
The team also noted a need for future studies evaluating dry eye symptoms over time, with additional clinical measurements and patient questionnaires.
Overall, “this study has significant importance in that it is the first to focus and compare symptomatic differences in DED between [non-Sjögren’s] and [Sjögren’s] patients,” the researchers wrote. “An advanced understanding of symptomatology in DED beyond clinicians’ observation would further improve patients’ quality of life.”