Ocular Pain and Dry Eye Disease: Insights from Tibetan Plateau Residents During COVID-19

A recent Chinese study has shed light on the prevalence and influencing factors of ocular pain in individuals suffering from dry eye disease (DED) residing at high altitudes on the Tibetan Plateau. Co-authored by Peng-Cheng Zhang, MD, PhD, and Wen-Shan Jiang, a PhD candidate, the research highlights the interplay of environmental, lifestyle, and psychological factors exacerbated during the COVID-19 pandemic.

Impact of COVID-19 on Dry Eye Disease

The researchers, affiliated with the General Hospital of Central Theater Command and Shaanxi Eye Hospital, emphasized how pandemic-induced changes like:

       • Increased indoor sterilization

       • Prolonged use of video terminals

       • Extended mask-wearing

       • Anxiety and stress

...triggered or worsened DED symptoms.

Special conditions on the Tibetan Plateau, such as low humidity, intense UV exposure, cold weather, low pressure, and hypoxia, add to the burden, making plateau residents particularly vulnerable to ocular complications. The study reported that the prevalence of DED at high altitudes is 26.1%, compared to 11.9% at lower elevations.

The Role of Ocular Pain in DED

Ocular pain, a significant but understudied symptom of DED, can manifest as:

       • Burning sensations

       • Grittiness

       • Discomfort

       • Stinging pain

The severity and frequency of ocular pain greatly affect patients’ quality of life and treatment compliance. The study aimed to provide a deeper understanding of this symptom and its influencing factors to enable tailored therapy strategies.

Study Design

The researchers conducted a retrospective analysis of 160 DED patients living above 2,500 meters on the Tibetan Plateau between July 2022 and June 2023. The data collected included:

       • Patient demographics (age, gender, occupation)

       • Illness history (duration, autoimmune diseases, history of ophthalmic medication)

       • Lifestyle factors (smoking, near-vision workload, sleep patterns)

       • Ocular assessments (OSDI scores, tear break-up time, Schirmer I test results)

       • Psychological factors (anxiety levels)

Key Findings

Prevalence of Ocular Pain

       • 77.5% of DED patients reported experiencing ocular pain.

       • Severity levels:

               - Mild: 30.0%

               - Moderate: 36.3%

               - Severe: 11.3%

       • Frequency levels:

               - Occasional: 19.4%

              - Half the time: 36.9%

              - Frequent: 16.9%

             - Persistent: 4.4%

Factors Influencing Ocular Pain

       1. Anxiety:

           • Anxiety was strongly correlated with increased severity and frequency of ocular pain.

           • Odds Ratios (OR) for anxiety levels:

                 - Mild anxiety: OR 3.662 (severity), 2.387 (frequency)

                 - Severe anxiety: OR 5.613 (severity), 4.870 (frequency)

       2. Professional Eye Protection and Sleep:

           • Using professional eye protection and improving sleep quality significantly reduced pain severity and frequency. 

          • Odds Ratios for eye protection and sleep:

                - Severity: OR 0.307 (eye protection), 0.572 (sleep)

                - Frequency: OR 0.418 (eye protection), 0.789 (sleep)

       3. Neutral Factors:

       • Smoking and general plateau protection measures had no significant effect on ocular pain (P>0.05).

Conclusion

The study concludes that ocular pain is a common and impactful symptom among DED patients living on the Tibetan Plateau, particularly during the COVID-19 pandemic. Epidemic-induced anxiety, alongside lifestyle adjustments such as sleep and eye protection, plays a critical role in the severity and frequency of this pain.

Understanding these factors is essential to developing effective, individualized treatment strategies to improve the quality of life for DED patients in high-altitude regions.

References:

Peng-Cheng Zhang, Wen-Shan Jiang, Ya-Zhen Wu, et al. Influencing factors of ocular pain in dry eye disease patients at high altitude. Int J Ophthalmol. 2024,17:2214-2220.

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