Evidence that dry eye is a comorbid pain condition in a U.S. veteran population

Association between potential factors and dry eye disease: A systematic review and meta-analysis

BACKGROUND

The 2017 TFOS DEWS II report provided an overview of the epidemiology of dry eye disease (DED) and identified several potential risk factors. This study aimed to conduct a meta-analysis on these potential risk factors.

METHODS

A comprehensive systematic search was conducted in PubMed, Embase, Web of Science, and Cochrane Library databases to include observational studies. Two researchers independently extracted adjusted odds ratios (AORs) and their 95% confidence intervals (CIs), and a random-effects model was used to combine the data. Results were reported using odds ratios (ORs) and their 95% CIs.

RESULTS

The meta-analysis results showed that the risk factors for DED were smoking (OR 1.18, 95% CI 1.07-1.29), alcohol consumption (OR 1.18, 95% CI 1.03-1.35), rosacea or acne (OR 1.96, 95% CI 1.56-2.45), allergic conjunctivitis (OR 4.59, 95% CI 3.38-6.23), refractive surgery (OR 1.78, 95% CI 1.05-3.00), diabetes (OR 1.14, 95% CI 1.06-1.22), thyroid disease (OR 1.57, 95% CI 1.36-1.82), viral infections (OR 1.54, 95% CI 1.33-1.78), anxiety (OR 2.39, 95% CI 1.30-4.39), depression (OR 1.59, 95% CI 1.39-1.82), post-traumatic stress disorder (OR 1.43, 95% CI 1.42-1.45), and stress (OR 1.59, 95% CI 1.24-2.05). However, there was no significant association between Hispanic ethnicity, menopause, past smoking, current smoking, multivitamin use, and DED.

CONCLUSION

These findings provide valuable insights for further research on the prevention and treatment of dry eye disease.

Discordant dry eye disease and chronic pain: A systematic review and meta-analysis

PURPOSE

To evaluate the relative contributions of objective and subjective indicators of dry eye disease (DED) in individuals with chronic pain conditions compared with controls.

METHODS

A systematic review and meta-analysis was conducted of studies that reported the signs and symptoms of DED and/or their prevalence in individuals with chronic pain compared with controls. International Association for the Study of Pain (IASP) International Classification of Diseases (ICD)-11 codes for chronic pain conditions were applied, and outcomes defined as DED signs and symptoms. A search strategy utilised the EMBASE, Web of Science, Cochrane Library and MEDLINE databases. Risk of bias assessment was performed with the Newcastle-Ottawa scale. Random effects meta-analysis calculated mean differences (MD) and odds ratios (OR), while subgroup analysis of different chronic pain conditions explored their relative association with the signs and symptoms of DED. Evidence certainty was evaluated using Grades of Recommendation, Assessment, Development, and Evaluation (GRADE).

RESULTS

Fourteen observational studies comprising 3,281,882 individuals were included. Meta-analysis found high quality evidence that individuals with chronic pain were more likely to experience symptoms of DED than controls (OR = 3.51 [95 %CI: 3.45,3.57]). These symptoms were more severe (MD = 18.53 [95 %CI: 11.90, 25.15]) than controls with a clinically meaningful effect size. Individuals with chronic pain had more rapid tear film disruption (MD = -2.45 [95 %CI: -4.20, -0.70]) and reduced tear production (MD = -5.57 [95 %CI: -9.56, -1.57]) compared with controls (with moderate evidence quality). High quality evidence revealed individuals with chronic pain had lower basal tear production (anaesthetised) than controls (MD = -2.59 [95 %CI: -3.60, -1.58]). Tear film osmolarity showed no significant differences between the chronic pain and pain-free groups. Group differences for DED signs were not considered clinically meaningful.

CONCLUSION

More severe, clinically meaningful symptoms of DED were reported in individuals with chronic pain than controls, however group differences for the signs of DED were typically of limited or questionable clinical relevance. This ocular phenotype where DED is felt more than it is seen in chronic pain may reflect underlying sensory hypersensitivity, shared by both conditions and contributing to their frequent comorbidity. Advancing understanding of this potential pathophysiological mechanism may guide clinical management.

Quantitative sensory testing and chronic pain syndromes: a cross-sectional study from TwinsUK

OBJECTIVE

The chronic pain syndromes (CPS) include syndromes such as chronic widespread pain (CWP), dry eye disease (DED) and irritable bowel syndrome (IBS). Highly prevalent and lacking pathognomonic biomarkers, the CPS are known to cluster in individuals in part due to their genetic overlap, but patient diagnosis can be difficult. The success of quantitative sensory testing (QST) and inflammatory biomarkers as phenotyping tools in conditions such as painful neuropathies warrant their investigation in CPS. We aimed to examine whether individual QST modalities and candidate inflammatory markers were associated with CWP, DED or IBS in a large, highly phenotyped population sample.

DESIGN

Cross-sectional study.

SETTING

Community-dwelling cohort.

PARTICIPANTS

Twins from the TwinsUK cohort PRIMARY AND SECONDARY OUTCOME MEASURES: We compared 10 QST modalities, measured in participants with and without a CWP diagnosis between 2007 and 2012. We investigated whether inflammatory markers measured by Olink were associated with CWP, including interleukin-6 (IL-6), IL-8, IL-10, monocyte chemoattractant protein-1 and tumour necrosis factor. All analyses were repeated in DED and IBS with correction for multiple testing.

RESULTS

In N=3022 twins (95.8% women), no association was identified between individual QST modalities and CPS diagnoses (CWP, DED and IBS). Analyses of candidate inflammatory marker levels and CPS diagnoses in n=1368 twins also failed to meet statistical significance.

CONCLUSION

Our findings in a large population cohort suggest a lack of true association between singular QST modalities or candidate inflammatory markers and CPS.

Dry eye symptoms and signs in United States Gulf War era veterans with myalgic encephalomyelitis/chronic fatigue syndrome

BACKGROUND

To examine ocular symptoms and signs of veterans with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) diagnosis, ME/CFS symptoms, and controls.

METHODS

This was a prospective, cross-sectional study of 124 South Florida veterans in active duty during the Gulf War era. Participants were recruited at an ophthalmology clinic at the Miami Veterans Affairs Hospital and evaluated for a diagnosis of ME/CFS, or symptoms of ME/CFS (intermediate fatigue, IF) using the Canadian Consensus criteria. Ocular symptoms were assessed via standardised questionnaires and signs via comprehensive slit lamp examination. Inflammatory blood markers were analysed and compared across groups.

RESULTS

Mean age was 55.1 ± 4.7 years, 88.7% identified as male, 58.1% as White, and 39.5% as Hispanic. Ocular symptoms were more severe in the ME/CFS (n = 32) and IF (n = 48) groups compared to controls (n = 44) across dry eye (DE; Ocular Surface Disease Index [OSDI]: 48.9 ± 22.3 vs. 38.8 ± 23.3 vs. 19.1 ± 17.8, p < 0.001; 5 item Dry Eye Questionnaire [DEQ-5]: 10.8 ± 3.9 vs. 10.0 ± 4.6 vs. 6.6 ± 4.2, p < 0.001) and pain-specific questionnaires (Numerical Rating Scale 1-10 [NRS] right now: 2.4 ± 2.8 vs. 2.4 ± 2.9 vs 0.9 ± 1.5; p = 0.007; Neuropathic Pain Symptom Inventory modified for the Eye [NPSI-E]: 23.0 ± 18.6 vs. 19.8 ± 19.1 vs. 6.5 ± 9.0, p < 0.001). Ocular surface parameters and blood markers of inflammation were generally similar across groups.

CONCLUSION

Individuals with ME/CFS report increased ocular pain but similar DE signs, suggesting that mechanisms beyond the ocular surface contribute to symptoms.

TFOS Lifestyle: Impact of lifestyle challenges on the ocular surface

Many factors in the domains of mental, physical, and social health have been associated with various ocular surface diseases, with most of the focus centered on aspects of dry eye disease (DED). Regarding mental health factors, several cross-sectional studies have noted associations between depression and anxiety, and medications used to treat these disorders, and DED symptoms. Sleep disorders (both involving quality and quantity of sleep) have also been associated with DED symptoms. Under the domain of physical health, several factors have been linked to meibomian gland abnormalities, including obesity and face mask wear. Cross-sectional studies have also linked chronic pain conditions, specifically migraine, chronic pain syndrome and fibromyalgia, to DED, principally focusing on DED symptoms. A systematic review and meta-analysis reviewed available data and concluded that various chronic pain conditions increased the risk of DED (variably defined), with odds ratios ranging from 1.60 to 2.16. However, heterogeneity was noted, highlighting the need for additional studies examining the impact of chronic pain on DED signs and subtype (evaporative versus aqueous deficient). With respect to societal factors, tobacco use has been most closely linked to tear instability, cocaine to decreased corneal sensitivity, and alcohol to tear film disturbances and DED symptoms.

Prevalence and Incidence of Dry Eye and Meibomian Gland Dysfunction in the United States: A Systematic Review and Meta-analysis

Importance

Dry eye is a common clinical manifestation, a leading cause of eye clinic visits, and a significant societal and personal economic burden in the United States. Meibomian gland dysfunction (MGD) is a major cause of evaporative dry eye.

Objective

To conduct a systematic review and meta-analysis to obtain updated estimates of the prevalence and incidence of dry eye and MGD in the United States.

Data Sources

Ovid MEDLINE and Embase.

Study Selection

A search conducted on August 16, 2021, identified studies published between January 1, 2010, and August 16, 2021, with no restrictions regarding participant age or language of publication. Case reports, case series, case-control studies, and interventional studies were excluded.

Data Extraction and Synthesis

The conduct of review followed a protocol registered on PROSPERO (CRD42021256934). PRISMA guidelines were followed for reporting. Joanna Briggs Institute and Newcastle Ottawa Scale tools were used to assess risk of bias. Data extraction was conducted by 1 reviewer and verified by another for accuracy. Prevalence of dry eye and MGD were combined in separate meta-analyses using random-effects models.

Main Outcomes and Measures

Prevalence and incidence of dry eye and MGD in the United States. Summary estimates from meta-analysis of dry eye and MGD prevalence with 95% CI and 95% prediction intervals (95% PI).

Results

Thirteen studies were included in the systematic review. Dry eye prevalence was reported by 10 studies, dry eye incidence by 2 studies, and MGD prevalence by 3 studies. Meta-analysis estimated a dry eye prevalence of 8.1% (95% CI, 4.9%-13.1%; 95% PI, 0%-98.9%; 3 studies; 9 808 758 participants) and MGD prevalence of 21.2% (95% CI, 7.2%-48.3%; 95% PI, 0%-100%; 3 studies; 19 648 participants). Dry eye incidence was 3.5% in a population 18 years and older and 7.8% in a population aged 68 years and older. No studies reported MGD incidence.

Conclusions and Relevance

This systematic review and meta-analysis demonstrated uncertainty about the prevalence and incidence of dry eye and MGD in the United States. Population-based epidemiological studies that use consistent and validated definitions of dry eye and MGD are needed for higher-certainty estimates of dry eye and MGD prevalence and incidence in the United States.

Risk of dry eye in headache patients: a systematic review and meta-analysis

OBJECTIVES

The objective of this meta-analysis was to identify whether headache increase the risk of dry eye disease (DED).

METHODS

PubMed, Web of Science, Cochrane Library and EMBASE databases were searched for relevant studies. The odds ratio (OR) of DED in all-cause headache was calculated via Stata software. To explore the source of heterogeneity, subgroup and sensitivity analyses were conducted. Funnel plots and Egger's test were performed to assess publication bias.

RESULTS

This meta-analysis included 11 studies. Pooled analysis indicated that all-cause headache was related to a higher risk of DED (OR = 1.586, 95% CI : 1.409-1.785, I² = 89.3%, p < .001). Migraine headache, tension headache and cluster headache were all related to a higher risk of DED (OR = 1.503, 95% CI: 1.369-1.650, I² = 81.8%, p < .001; OR = 1.610, 95% CI: 1.585-1.635, p < .001; OR = 2.120, 95% CI: 1.104-4.073, p = .024), respectively. The risk of DED in case-control studies was slightly higher than in cross-sectional studies and cohort study (OR = 1.707, 95% CI: 1.291-2.258, I² = 85.0%, p < .001; OR = 1.600, 95% CI: 1.590-1.610, I² = 0.0%, p < .001; OR = 1.440, 95% CI: 1.096-1.893, p = .009), respectively. Subgroup analysis in territory type showed that all-cause headache in America, Europe, Asia and Oceania were all related to a higher risk of DED.

CONCLUSIONS

This study indicates that headache is related to a higher risk of DED, especially in the migraine patients. These results suggest that headaches should be regarded as an independent risk factor for DED.KEY MESSAGESIn this meta-analysis, 11 studies (one cohort study, four case-control studies and six cross-sectional studies) covering 3,575,957 individuals were included.Pooled analysis indicated that all-cause headache was related to a higher risk of dry eye (OR = 1.586, 95% CI: 1.409-1.785, I² = 89.3%, p < .001).These results suggest that headaches should be regarded as an independent risk factor for dry eye.

Association Between Dry Eye Syndrome and Osteoarthritis Severity: A Nationwide Cross-Sectional Study (KNHANES V)

OBJECTIVE

Recently, several researchers reported an association between osteoarthritis and dry eye syndrome (DES) and suggested that they may be related to central sensitization. We investigated the association between DES, osteoarthritis pain, and radiographic severity.

DESIGN

A nationwide, cross-sectional study.

SETTING

The Fifth Korean National Health and Nutrition Examination Survey.

SUBJECTS

8,664 participants in this survey.

METHODS

Osteoarthritis-associated radiographic changes were evaluated by trained radiologists. Multivariable logistic regression was performed to examine the relationship between osteoarthritis pain, radiographic severity, and DES. The odds ratios (ORs) of DES were analyzed in accordance with the presence of osteoarthritis-associated factors.

RESULTS

Radiographic knee osteoarthritis was significantly associated with lower ORs for DES (OR = 0.80, P = 0.046, for diagnosed/self-reported DES; OR = 0.84, P = 0.034, for symptoms of DES). Knee pain or stiffness was significantly associated with higher ORs for DES (OR = 1.28, P = 0.020, for diagnosed/self-reported DES; OR = 1.29, P = 0.003, for symptoms of DES). In patients with symptomatic osteoarthritis, DES was not significantly associated with radiographic severity of osteoarthritis. In patients with nonsymptomatic radiographic osteoarthritis, DES was inversely related with radiographic severity (Ptrend = 0.012 for diagnosed/self-reported DES; Ptrend < 0.001 for symptoms of DES).

CONCLUSIONS

Radiographic osteoarthritis showed a significant association with decreased DES. Patients with less pain and severe radiographic OA were more likely to have less DES. Our results suggest that the degree of pain caused by osteoarthritis and central sensitization may be closely associated with DES.

Association Between Migraine and Dry Eye: A Systematic Review and Metaanalysis

PURPOSE

The purpose of this study was to assess whether migraine might be associated with the increased risk of dry eye disease and to determine the strength of the association between migraine and dry eye disease.

METHODS

We searched EMBASE, PubMed, Web of Science databases and China National Knowledge Infrastructure, WanFang, and VIP databases for studies that investigated the association between dry eye and migraine from inception to September 8, 2020. Relevant data were extracted by 2 investigators independently. Publication bias and heterogeneity were evaluated. Odds ratio (OR) and 95% confidence interval (CI) were computed by metaanalysis using random-effects models.

RESULTS

Of the 565 studies identified, 7 studies met the inclusion criteria and were included in this metaanalysis. Patients with migraine had significantly higher morbidity of dry eye compared with the control group (OR = 1.55; 95% CI = 1.32-1.82; P < 0.001). Subgroup analysis showed that the association between dry eye and migraine was stronger in hospital-based studies (OR = 1.97, P = 0.036) than population-based studies (OR = 1.42, P < 0.001). In addition, differences in geographic location and diagnostic criteria have no effect on the results.

CONCLUSIONS

There was a significant association between dry eye and migraine. Patients with migraine are more prone to suffer from dry eye than subjects without migraine, and the association strength varies among populations studied.

Pain sensitivity and autonomic nervous system parameters as predictors of dry eye symptoms after LASIK

PURPOSE

Differences in pain processing and autonomic function among patients have been implicated in the development of chronic pain after surgery. This study was designed to evaluate whether pain and autonomic metrics predict severity of chronic dry eye (DE) symptoms after LASIK, as there is increasing evidence that DE symptoms may be manifestations of persistent post-operative ocular pain.

METHODS

Secondary analysis of prospective randomized clinical trial. Patients were treated with either pregabalin or placebo. As no significant differences in DE symptoms were detected by treatment allocation at six months, all participants were grouped together for the present analyses. Subjects were evaluated pre-LASIK with regard to evoked pain sensitivity (utilizing quantitative sensory testing), autonomic metrics and DE and ocular pain symptoms (via validated questionnaires). Measures of DE and ocular pain were assessed post-LASIK, and the Dry Eye Questionnaire 5 (DEQ5) score 6-months after surgery was the primary outcome of interest.

RESULTS

43 individuals were randomized to pregabalin (n = 21) or placebo (n = 22). 42 completed the 6-month visit. Several baseline autonomic metrics correlated with 6-month post-operative DEQ5 scores, including lower systolic (r -0.37, p = 0.02) and diastolic blood pressure (r -0.32, p = 0.04). Ocular pain at 6 months was also negatively correlated with blood pressure (r -0.31, p = 0.047). The presence of painful aftersensations was a significant predictor of chronic DE symptoms at 6 months (mean DEQ5 scores: 8.0 ± 1.9 versus 5.0 ± 5.0, p = 0.009).

CONCLUSIONS

Heightened parasympathetic tone and prolonged pain sensitivity measured prior to surgery predicted greater DE symptom severity 6 months after LASIK.

TRIAL REGISTRATION

NCT02701764.

Digital Screen Use and Dry Eye: A Review

Prolonged and continuous daily use of digital screens, or visual display terminals (VDTs), has become the norm in occupational, educational, and recreational settings. An increased global dependence on VDTs has led to a rise in associated visual complaints, including eye strain, ocular dryness, burning, blurred vision, and irritation, to name a few. The principal causes for VDT-associated visual discomfort are abnormalities with oculomotor/vergence systems and dry eye (DE). This review focuses on the latter, as advances in research have identified symptomology and ocular surface parameters that are shared between prolonged VDT users and DE, particularly the evaporative subtype. Several mechanisms have been implicated in VDT-associated DE, including blink anomalies, damaging light emission from modern devices, and inflammatory changes. The presence of preexisting DE has also been explored as an inciting and exacerbating factor. We review the associations between digital screens and DE, mechanisms of damage, and therapeutic options, hoping to raise awareness of this entity with the goal of reducing the global morbidity and economic impact of screen-associated visual disability.

Modification of the Neuropathic Pain Symptom Inventory for use in eye pain (NPSI-Eye)

Chronic eye pain, which has previously been assumed to be due to ocular surface abnormalities (ie, "dry eye [DE] disease"), has recently garnered attention as a potential indicator of neuropathic ocular pain in some patients. The purpose of this study was to evaluate the psychometric properties of a modified version of the Neuropathic Pain Symptom Inventory in individuals with eye pain (NPSI-Eye). Enrolled participants (n = 397) completed the NPSI-Eye, general pain severity questionnaires, DE symptom report, and psychological health indices. Participants also underwent mechanical pain sensitivity testing of the cornea, tear film assessment, and evaluation of the efficacy of anesthetic eye drops to relieve pain. Short-term test-retest reliability of the NPSI-Eye was excellent (intraclass correlation coefficient = 0.98, P < 0.001). Correlations between the NPSI-Eye and indicators of general eye pain were ≥0.65 (P < 0.001), whereas correlations between the NPSI-Eye and DE symptom severity and psychological health indices were lower (rho = 0.56, 0.32, 0.37; all P < 0.001). Individuals who reported little or no decrease in pain after anesthetic eye drops (hypothesized to indicate eye pain with at least partial central involvement) had significantly higher NPSI-Eye scores than participants whose eye pain was completely relieved by anesthetic (P < 0.05). Overall, our results support preliminary validation of the NPSI-Eye, yielding similar metrics to those reported in Bouhassira et al.'s original NPSI publication (2004). However, additional evaluation and refinement of some questions may be desirable, including the potential elimination of items that were not highly endorsed.

Association Between Dry Eye Disease and Migraine Headaches in a Large Population-Based Study

Importance

Reports in the literature have conflicting findings about an association between dry eye disease (DED) and migraine headaches.

Objective

To determine the strength of the association between DED and migraine headaches.

Design, Setting, and Participants

This retrospective case-control study included 72 969 patients older than 18 years from University of North Carolina-affiliated health care facilities from May 1, 2008, through May 31, 2018. Deidentified aggregate patient data were queried; data were analyzed from June 1 through June 30, 2018.

Exposures

Diagnosis of migraine headache.

Main Outcomes and Measures

Odds ratios calculated between DED and migraine headaches for participants as a whole and stratified by sex and age group.

Results

The base population consisted of 72 969 patients, including 41 764 men (57.2%) and 31 205 women (42.8%). Of these, 5352 patients (7.3%) carried a diagnosis of migraine headache, and 9638 (13.2%) carried a diagnosis of DED. The odds of having DED given a diagnosis of migraine headaches was 1.72 (95% CI, 1.60-1.85) times higher than that of patients without migraine headaches. After accounting for multiple confounding factors, the odds of having DED given a diagnosis of migraine headaches was 1.42 (95% CI, 1.20-1.68) times higher than that of patients without migraine headaches.

Conclusions and Relevance

These findings suggest that patients with migraine headaches are more likely to have comorbid DED compared with the general population. Although this association may not reflect cause and effect if unidentified confounders account for the results, these data suggest that patients with migraine headaches may be at risk of carrying a comorbid diagnosis of DED.

Do Sleep Disorders Positively Correlate with Dry Eye Syndrome? Results of National Claim Data

Purpose: Dry eye syndrome (DES) is a common disease with an increasing occurrence. Although DES symptoms are considered mild, it can reduce quality of life for individuals. Many studies on DES have been conducted, but these focused on the use of electronic devices. Here, we investigate an association between DES and sleep disorders in the context of emerging health issues. Methods: Our data came from the National Health Insurance Service (NHIS) National Sample Cohort, which included 44,366 patients and was based on a 1:1 matching method (sleep disorder patients vs. patients without sleep disorders) during 2012–2015. Using survival analysis with a Cox proportional hazard model, we identified an association of sleep disorders with DES. Results: About 16.7% of all patients were diagnosed with DES, and prevalence was higher in patients with sleep disorders (sleep disorders: 19.82%, no sleep disorders: 13.67%). Survival analysis showed that sleep disorders positively correlated with DES diagnosis (Hazard Ratio (HR): 1.320, 95% Confidence Interval (CI): 1.261–1.382, p-value < 0.0001). Positive trends were enhanced in males, younger patients, lower economic levels, and with higher severity of comorbid. Conclusions: Our findings suggest that sleep disorder was positively associated with DES. This correlation can be helpful in effective management of both sleep disorders and DES in South Koreans.

What's new in dry eye disease diagnosis? Current advances and challenges

Dry eye disease (DED) is a commonly encountered condition in general ophthalmology practice and imparts a significant socioeconomic burden. Despite its prevalence, there remain challenges regarding its diagnosis and management. A major reason behind these challenges is the fact that DED represents an umbrella term that encompasses many different underlying conditions and pathophysiological mechanisms. The purpose of this article is to highlight aspects of DED pathophysiology and focus on targeted diagnostic and therapeutic approaches to this multifactorial, chronic condition.