Ocular Manifestations of Psoriasis

Psoriasis is an immune-mediated disorder that primarily affects the skin, nails, and joints. However, it can lead to several systemic complications, including cardiovascular, metabolic, and psychiatric problems. Previous studies have shown some ocular manifestations in patients with psoriasis, especially those with arthropathic or pustular variants of the disease.

The most common ocular manifestations among patients with psoriasis are keratoconjunctivitis sicca (dry eye syndrome), nonspecific conjunctivitis, blepharitis, cataract and uveitis.

Ophthalmological involvement may be due to the systemic and inflammatory nature of the disease, as well as the use of some treatments such as methotrexate, acitretin, biological drugs and phototherapy.

Since ocular manifestations are usually mild and nonspecific, they could be easily missed, which could be one of the explanations for the wide range of their incidence rate, from 10% to 58% in several studies.

It has been shown that ocular manifestations in psoriatic patients are always preceded by skin lesions. Therefore, dermatologists and general practitioners could be considered as sentinel physicians, and evaluation of patients’ presentations needed additional evaluations by the ophthalmologist.

Since some discrepancies were found in the results of previous studies regarding the prevalence and also the risk factors of ocular involvement in patients with psoriasis, this study aimed to evaluate the incidence of various ocular manifestations in patients with psoriasis and compare it. with the normal population. The association of demographic and clinical characteristics of patients with ocular manifestations was also addressed.

Background

Psoriasis is a chronic inflammatory disorder that primarily affects the skin.

Goals

To evaluate the prevalence of ocular manifestations in Iranian patients with psoriasis, compared with healthy controls.

Materials and methods

Forty psoriasis patients and 40 age- and gender-matched healthy controls were enrolled in the study and underwent a comprehensive ophthalmologic evaluation.

Inclusion criteria:

• Those with a confirmed diagnosis of psoriasis for the patient group and healthy subjects for the control group.
   
• Willing to participate in the study.

Exclusion Criteria:

• Subjects with any known dermatological or systemic disorder (except psoriasis for the patient group).
   
• Those who have received any systemic treatment or phototherapy during the last 6 months.
• Those with a personal or family history of eye disorders.

Results

Only meibomian gland dysfunction was significantly more common among psoriasis patients compared to the control group (p value: 0.011).

Regarding intraocular pressure (IOP), the mean values ​​for both patients and healthy controls were within the normal range and the mean IOP in patients was even lower than normal controls, although this difference was significant only for the left eye (p value: 0.049).

A strong positive correlation was observed between PASI and tear meniscus height for the right and left eyes (p value: 0.005, r: 0.44 for OD and p value: 0.003, r: 0.46 for OS).

Meibomian gland dysfunction was also positively correlated with the duration of right and left eyelid disease (p: 0.04, r: 0.31 for both).

Conclusion

Psoriasis can cause meibomian gland dysfunction, especially in patients with long-term disease. Therefore, dermatologists and general practitioners should be vigilant in this regard when visiting patients with psoriasis, especially those who have higher PASI values ​​or long-standing disease.

Discussion

Meibomian glands are large sebaceous glands located in the tarsal plates of the eyelids. Dysfunction of the meibomian glands causes abnormalities in tear formation that lead to abnormal dryness of the eyes. Dry eye disease ( DED) is the most common ocular surface disease, which is considered a serious and growing public health problem due to its high prevalence worldwide. Patients with this problem experience various symptoms and visual impairment can lead to reduced quality of life related to vision-related tasks or damage to the ocular surface.

Dry eye disease is a multifactorial disease with several known risk factors, including Asian ethnicity, female gender, and older age. Previous research has shown its higher prevalence in patients with psoriasis. In fact, it has been shown that psoriasis is not a mere skin disorder , but that other organs can be affected by systemic inflammation.

Ocular involvement , especially corneal manifestations in psoriasis, may have been underestimated by physicians and has not been studied exhaustively. The reported incidence rate of ocular manifestations in patients with psoriasis ranged from 10% to 58%. In our study, only meibomian gland dysfunction was found to be significantly more prevalent in patients with psoriasis compared to the healthy control group (15% vs 0%).

Although chronic conjunctivitis and Stargardt disease were also more common in the patient group, the difference did not reach the level of significance. These results were consistent with previous studies that reported no significant difference in the incidence of cataracts, uveitis, and macular edema in patients with psoriasis, compared with the normal population.

An interesting finding of this study was the lower intraocular pressure (IOP) in the patients, compared to healthy controls. We could not find any reason for that and it could be a purely incidental finding, but we suggest future studies to shed more light on this issue and clarify whether psoriasis could be considered as a protective factor for glaucoma.

We could not find any association between the ocular manifestation and the clinical type of psoriasis, which could be due to the insufficient number of cases of different clinical types and also the absence of some types, such as the pustular or erythrodermic variants, which have been shown to are associated with severe dry eye. Syndrome in patients with psoriasis.

Our study was limited by its small sample size which did not allow us to have enough patients with various clinical types and severity to evaluate the effect of these factors on ocular involvement. Future prospective studies with a larger sample size are needed to further address this issue.