Do new daily disposable lenses improve patient comfort?

Numerous studies over the past 15 years have indicated the significant frequency and intensity of dryness and discomfort-related symptoms patients experience during contact lens wear.

Across the various polymer materials, modalities and wearing schedules, this research has indicated that about 50 per cent of contact lens wearers are clinically symptomatic. Further, more recent studies have also indicated that these symptoms increase over the course of a day's wear of contact lenses. Dryness symptoms can lead to reduced wearing times, dissatisfaction with contact lenses, and ultimately to failure of lens wear.

Weekly disposable lenses were first introduced in 1987 by Johnson & Johnson Vision Care (Acuvue, etafilcon A), followed soon thereafter by the world's first daily disposable lens in June 1993 (1 Day Acuvue, etafilcon A).

Daily disposables eliminate the need for a daily lens care regimen, offering a significant convenience advantage to the patient. Further, there is little potential for solution-related sensitivities associated with this modality. While the daily disposable modality is associated with improved health and comfort-related outcomes, to date there has been relatively little indication that the daily disposable modality has had a significant impact on over-arching, comfort-related issues associated with traditional contact lens materials and modalities. While daily disposables are novel in terms of their lack of corresponding deposition-related problems, these lenses are typically manufactured from the same or similar polymers from which their frequent replacement counterparts are derived.

In this regard, improvements in polymers associated with the daily disposable modality may too lead to significant improvements in patient comfort, which in turn will allow wearers to appreciate the full spectrum of comfort and health benefits associated with this unique modality. For example, while we don't completely understand the role of the silicone hydrogel lenses in terms of their impact on contact lens-related dry eye,  there have been reports suggesting that these new polymers can be associated with improved patient comfort. This too could be especially true of novel polymers developed specifically for the daily disposable modality.

Recently, Johnson & Johnson Vision Care and CIBA Vision released two daily disposable lenses, both based on existing polymer materials, but that have incorporated ingredients via new technologies. The Focus Dailies with AquaComfort lens is derived from its nefilcon A material (FDA Group II), but now includes more polyvinyl alcohol (PVA) in the polymer.

Johnson & Johnson Vision Care's new lens, 1 Day Acuvue Moist, is made from its etafilcon A material (FDA Group IV), but now includes a moisture retaining agent, polyvinyl pyrrolidone (PVP) throughout the polymer matrix. Through a proprietary 'Lacreon' technology, PVP is locked into  the etafilcon A matrix. This technology enhances moisture retention and significantly reduces the coefficient of friction of the lens surface. The PVP is not released from the polymer over a day's wear, and thus is not blinked away.
The primary purpose of this report is to compare subjective outcomes associated with these two lenses.