Complementary Treatment of Allergic Conjunctivitis: The Role of Quercetin

Case Series

Austin J Allergy. 2022; 8(1): 1042.

Complementary Treatment of Allergic Conjunctivitis: The Role of Quercetin

Mazzolani F¹, Togni S², Petrangolini G², Allegrini P² and Riva A²*

¹Private Practice, Centro Oculistico Bergamasco, Bergamo, Italy

²Research and Development Department, Indena SpA, Viale Ortles 12 - 20139 Milan, Italy

*Correspoing author: Riva A, Research and Development Department, Indena SpA, Viale Ortles 12 - 20139 Milan, Italy

Received: October 10, 2022; Accepted: November 04, 2022; Published: November 11, 2022

Abstract

Quercetin offers interesting beneficial options in clinical practice by providing anti-allergic and anti-inflammatory activities. This article reports and discusses the effectiveness of oral administration of quercetin Phytosome™ in adults presenting allergic conjunctivitis. The analysis was conducted by evaluating both subjective symptoms reported by individuals; and objective analysis of tear film instability due to allergic conjunctivitis inflammation using a non-invasive and computerized evaluation model. Outcomes provided evidence that quercetin Phytosome may significantly be a natural effort to avoid clinical worsening when supplemented as add-on to continuous anti-histaminic treatment and also prevent clinical exacerbations.

Keywords: Allergic conjunctivitis; Quercetin; Tear film non-invasive BUT; Inflammation; Phytosome

Introduction

Quercetin, a natural substance belonging to the family of bioflavonoids, is present in fruits (grapefruit, apples, berries), vegetables (beans, onions, capers and broccoli), as well as red wine and black and green tea [1]. Due to its inhibitory activity on enzymes like lipoxygenase and peroxidase, and its ability to suppress proinflammatory mediators release such as interleukin 4, quercetin possesses anti-inflammatory and immunomodulating properties [2- 5].

Outdoor and indoor allergens exposure can cause allergic conjunctivitis, a disorder affecting the quality of life of many people. Current therapies range from drugs (i.e. antihistaminic, mast cell stabilizers, anti-inflammatory, corticosteroids and immunomodulators) both systemically and topically administered, to natural substances that can be of support [6]. Benefits of quercetin in allergic conditions have been recently reviewed [7], where the effects of quercetin in vitro and in vivo models in allergic asthma, allergic rhinitis and atopic dermatitis are fully summarized and shown.

Therefore, these outcomes confirm and underline quercetin anti-allergic benefits and the potential indication as a natural help in Allergic Conjunctivitis (AC). This clinical study was performed to evaluate the efficacy of 500 mg/day for 2 weeks of oral consumption of bioavailable quercetin (quercetin Phytosome, Quercefit™) for the relief of ocular symptoms, improvement stability of tear film and reduction of anti-allergic medications use in adults with allergic conjunctivitis.

Material and Methods

30 Eyes of 15 subjects (12 women, mean age 42 years, and 3 men, mean age 38 years) were considered. Subjects were followed according to standard clinical practice, using standard diagnostic and intervention procedures, without any foreseeable risk for the evaluated subjects in line with the practice of our Center. A complete eye examination was performed and in all cases an analysis using a new Dry Eye module was performed (VX210®Visionix Medical Italy). Placido-disc technology allows advanced analysis of precorneal tear film structure and stability. The concentric ring pattern is projected onto cornea and subject is asked to blink. The rings will be distorted as soon as the cornea becomes dry. The time interval between last blink and the appearance of a distorted ring pattern gives the measurement of Non Invasive First Breakup Time (NIBUT).

Subjects were visited at baseline before the treatment and after 15 days of supplementation with Quercefit™ (a solid dispersion of quercetin in phospholipids, Indena SpA) at the dosage of 2 tablets/ day (500 mg total).

The only local therapy used was Olopatadine, 0.1% solution (Alcon, US), one drop in each affected eye twice per day for 2 weeks. No topical antibiotic or corticosteroid therapy was allowed.

After 15 days, the topical therapy was suspended, while quercetin Phytosome was continued for further 2 weeks, in order to monitor potential relapses.

The primary efficacy endpoint was the change in mean Total Ocular Symptom Score (TOSS) from baseline after 2 weeks of study supplementation. Ocular signs and symptoms were recorded using the TOSS scale (where 0 = no symptoms; 1 = mild symptoms; 2 = moderate symptoms and 3 = severe symptoms) for the following ocular signs and symptoms: itching, lacrimation, conjunctival congestion, hyperemia and photophobia at baseline and after 15 days.

The TOSS score as sum of the single parameters was calculated, according to literature [8,9] at time 0 and time 15days.

The secondary efficacy endpoint was tear break-up time (NIBUT) improvement after 2 weeks of supplementation using non-invasive Scheimpflug Camer examination (VX210® Visionix Medical, Italy).

Several non-invasive instruments are used for automatic Non- Invasive Tear Breakup Time (NIBUT) measurements [10]. In noninvasive procedure, a grid or concentric ring pattern is projected onto cornea and subject is asked to blink; the rings will appear distorted when cornea becomes dry. Generally, >10 seconds is thought to be normal [11-13] 5 to 10 seconds, borderline, and < 5 seconds is considered low.

NIF-BUT (Non Invasive First Breakup Time) and NIAvg-BUT (Non Invasive Average Breakup Time) data were collected.

NIF-BUT indicates, in seconds, the time that elapses at the opening of the eye following one or more blinks and the instant in which the first tear film break occurs or the moment in which a further blink occurs.

NIAvg-BUT indicates, in seconds, the average tear film breakup time calculated by considering the average of all corneal sectors during the entire measurement.

Statistical analysis of TOSS data at T15 vs T0 was performed by Wilcoxon test (two tails). The Student’s t-test was used to assess the statistical significance of changes in non-invasive tear breakup time (NIF-BUT and NIAvg-BUT) and p< 0.05 was considered statistically significant.

Results

All subjects reported improvement in primary and secondary endpoints. As described in Figure 1, the 100% of subjects reported almost complete restoring (p<0.0001) after supplementation in TOSS score, considered as sum of the individual symptoms (Figure 1, left) and as individual fifteen T0-T15 values (Figure 1, right).