Sally Dillehay

The stability of dryness symptoms after refitting with silicone hydrogel contact lenses over 3 years.

Purpose. To assess the stability of dryness symptoms after refitting patients wearing low-Dk/t hydrogel contact lenses with high-Dk/t silicone hydrogel contact lenses and to determine whether early dryness symptoms were predictive of discontinuation in the 3-year study. Methods. Two hundred seventy-eight hydrogel lens wearers were refitted with lotrafilcon A silicone hydrogel contact lenses for continuous wear of up to 30 nights. Self-administered questionnaires at baseline, 1 week, and 3 years captured the frequency and intensity of dryness symptoms during the day and at the end of the day. One-week and 3-year responses were compared to baseline by a Bowker test of symmetry and median change in response with Wilcoxon signed rank test. Results. Frequency of during-the-day and end-of-day dryness decreased from baseline to 1 week and 3 years (during the day, frequency ≥ “sometimes” 57.1% vs. 33.1% after 1 week and 58.5% vs. 28.8% after 3 years; end of day, 61.1% vs. 41.0% after 1 week and 64.0% vs. 35.9% after 3 years [P<0.0001 for all comparisons]). After refitting, the proportion of subjects with dryness symptoms was stable. After 1 week, the presence of frequency of at least “sometimes” and severity of at least “moderate” during-the-day and end-of-day dryness were significantly associated with study discontinuation (during-the-day frequency [P=0.007] and severity [P=0.017]; end-of-day frequency [P=0.002] and severity [P=0.003]). Conclusions. Dryness symptoms improved after 1 week of refitting with lotrafilcon A and remained stable through 3 years. The presence of dryness after 1 week was associated with discontinuation from contact lens wear. Refitting with silicone hydrogel lenses reduced the frequency and severity of dryness symptoms seen with hydrogel lens wear for many subjects.

Impact of previous extended and daily wear schedules on signs and symptoms with high Dk lotrafilcon A lenses.

Purpose. This study measured the impact of previous contact lens wearing schedule on the resolution of signs and contact lens-related symptoms among wearers of lotrafilcon A lenses. Methods. One hundred forty adapted low Dk daily wear (DW) and 140 adapted low Dk extended wear (EW) subjects were enrolled and examined for 1 year (overall study length is 3 years). All subjects wore lotrafilcon A lenses on a wearing schedule of up to 30 nights continuous wear with monthly replacement of lenses. Examinations were conducted at 1 week, 1, 6, and 12 months. Results. The former EW wearers presented at baseline with significantly higher conjunctival staining and epithelial microcysts (p < 0.05) and lower ocular surface symptoms of end of day dryness than the former DW wearers. There were no significant differences in other ocular signs at baseline for the former DW and EW wearers. After use of lotrafilcon A, clinical signs of limbal, conjunctival redness, and neovascularization were significantly better by the 1-week visit for both groups of wearers. Regardless of former wearing schedule, symptoms of dryness (during and at the end of the day) and photophobia were significantly better after 1 week of lotrafilcon A use. The frequency and severity of symptoms of dryness during the day improved significantly among former low Dk DW and EW wearers within 1 week as did severity of dryness during the day for the former DW wearers, in part as a result of their higher prevalence at baseline in the DW group. Subjects reported redness improved significantly by the 1-month visit. Conclusions. Continuous wear of high Dk silicone hydrogel lenses resulted in an improvement in ocular redness and neovascularization and dryness symptoms among subjects in this trial, regardless of their previous low Dk lens-wearing schedule. All improvements in signs and symptoms were sustained through 12 months.

Improving contact-lens related dryness symptoms with silicone hydrogel lenses.

Purpose. To determine dryness symptoms attributable to hydrogel contact lens (HCL) wear by comparing symptoms from age-matched HCL wearers and non-wearers in a cross-sectional study, and to compare that difference to the change in proportion of subjects reporting frequent dryness among HCL wearers after refitting with lotrafilcon A or B silicone hydrogels (SHCLs). Methods. Prevalence of frequent dryness symptoms was compared between HCL and non-wearers from a cross-sectional, historical dataset of Dry Eye/Contact Lens Dry Eye Questionnaires using an age-matched subset of 259 HCL and 246 non-wearers. Prospective change in prevalence of frequent dryness from non-randomized studies (n = 1036), in which daily wear (DW) HCL wearers were refit with lotrafilcon A or B SHCLs, was then compared to the cross-sectional difference between HCL wearers and non-wearers. Results. In the Dry Eye/Contact Lens Dry Eye Questionnaires dataset, 47% fewer non-wearers reported frequent dryness than HCL wearers (p = 0.0001). In the lotrafilcon A DW refitting trials, frequent dryness was reported by 67 and 62% fewer subjects for during the day (DD) and end of the day (EOD) dryness (p = 0.0001, both) after refitting. In continuous wear lotrafilcon A trials, there were 63 and 41% reductions in the proportion reporting frequent DD and EOD dryness (p = 0.014 and p = 0.02). Refitting to DW lotrafilcon B yielded a 48 and 46% reduction in the number of subjects reporting frequent DD and EOD dryness (p < 0.0001, both). Conclusions. After refitting DW HCL wearers with either lotrafilcon A or B SHCLs, the proportion of symptomatic wearers was approximately half; an amount similar to the difference in proportion between HCL and non-wearers. This raises the possibility that refitting HCL wearers with SHCLs eliminates the component of dryness that is induced by HCL wear. Further research with more robust experimental design is recommended to test this hypothesis.

Does the level of available oxygen impact comfort in contact lens wear?: A review of the literature.

Purpose. Wear of low-Dk/t lenses has long been associated with signs and symptoms indicative of hypoxia and with patient symptoms of dryness and discomfort. Although patient discomfort during soft contact lens wear has been generally attributed to lens dehydration, research studies aimed at verifying that connection have been unsuccessful. With the advent of high-Dk/t silicone hydrogel lenses, not only have improvements in clinical signs of hypoxia been documented, but improvements in patient symptoms of dryness and discomfort also have been documented. This literature review was undertaken to examine historic and current literature to determine whether the level of available oxygen is associated with patient symptoms of dryness and discomfort. Methods. Literature was reviewed related to soft contact lens dehydration, corneal hypoxia, patient symptoms of dryness and discomfort, and current clinical studies of silicone hydrogel lens wear. Results. Through the years, the body of knowledge has grown supporting a connection between decreased levels of available oxygen to the cornea caused by low-Dk/t contact lens wear and negative impacts on the signs of corneal health and patient symptoms. Conclusions. Available published literature suggests that many of these changes in patient signs and symptoms seen with low-Dk/t lens wear may be related to an inflammatory response. Clinical studies of high-Dk/t silicone hydrogel lenses further support a significant connection between the level of available oxygen during contact lens wear and improved patient symptoms of comfort, including dryness.

Long-term clinical results: 3 years of up to 30-night continuous wear of lotrafilcon A silicone hydrogel and daily wear of low-Dk/t hydrogel lenses.

Purpose. To summarize results of a 3-year clinical trial assessing subjective and objective experience with lotrafilcon A silicone hydrogel (SH) lenses for up to 30 nights of continuous wear or low-Dk/t daily-wear (LDW) hydrogel lenses. Methods. Nineteen sites dispensed SH lenses to 317 subjects (286 current wearers and 31 new wearers) and 2-week replacement LDW lenses to 81 new wearers in a 3-year study. Results. For the SH cohort, limbal redness, conjunctival redness, and corneal neovascularization improved among 23%, 21%, and 13% of eyes, respectively (P<0.001), with no signs increasing significantly. For the LDW cohort, limbal redness, papillary conjunctivitis, and corneal staining increased among 11%, 21%, and 13% of eyes, respectively (P<0.02), with no signs improving significantly. The change in average spherical equivalent power was –0.03 diopters for the age-matched SH cohort and –0.40 diopters for the LDW cohort (P=0.007). During the 3 years, the SH group reported significantly less frequent dryness during and at the end of the day, redness, photophobia, lens awareness, and blurred vision. Significantly more LDW lens wearers reported frequent during-the-day and end-of-day dryness and blurred vision. Conclusions. During the 3 years, lotrafilcon A lens wearers who wore their lenses continuously for up to 30 nights showed stable, long-term improvements in many signs of corneal health and symptoms along with less myopic progression versus daily wearers of low-Dk/t hydrogel lenses. Many biomicroscopy signs and symptoms worsened among neophytes wearing daily-wear low-Dk/t hydrogel lenses. The use of lotrafilcon A lenses may minimize many ocular changes from soft contact lens wear.

Myopia progression during three years of soft contact lens wear.

Purpose. To analyze the effect of lens material alone on myopia progression in a multi-center non-randomized prospective study of daily wear hydrogel and continuous wear silicone hydrogel contact lenses. Methods. Refractive error data from completing subjects were collected during a 3-year study of 54 subjects wearing low-Dk/t hydrogel contact lenses for daily wear and 230 wearing silicone hydrogel contact lenses for up to 30 nights continuous wear. Univariate analysis of refractive error changes was first conducted on factors of lens type, age at baseline, and baseline refractive error. Multivariate analysis was then performed to control for potential confounders of age (categorical by decade and continuous), and baseline refractive error. Results. Multivariate analysis showed that refractive error changes were significantly affected by lens type (F = 78.2, p < 0.001, R2 = 0.218) and subject age (F = 131.2, p < 0.001, R2 = 0.319) but not baseline refractive error (F = 2.56, p = 0.11, R2 = 0.009). The model’s overall R2 value is 0.376; the age-adjusted refractive error changes are +0.02 D for the silicone hydrogel contact lens wearers and –0.41 D for the hydrogel contact lenses for the 3-year follow-up period. Conclusions. Subject age and lens type significantly influenced the degree of myopic progression, with younger subjects and low-Dk/t hydrogel contact lens wearers increasing more during the study. The Lotrafilcon A silicone hydrogel lens material may contribute to less myopia progression in adult contact lens wearers.

Inflammatory and mechanical complications associated with 3 years of up to 30 nights of continuous wear of lotrafilcon A silicone hydrogel lenses.

Purpose. To report the ocular complications occurring during a 3-year clinical trial of subjects wearing lotrafilcon A silicone hydrogel lenses for up to 30 nights of continuous wear. Methods. Nineteen sites enrolled 317 subjects (286 current wearers and 31 new wearers), who were dispensed lotrafilcon A lenses with 3 years of follow-up. Results. By the 1-month visit, continuous wear of up to 30 nights was recommended for 87% of subjects. The 27 lens-related adverse events included 15 (2.4%) eyes in year 1, seven (1.3%) eyes in year 2, and five (0.8%) eyes in year 3. Lens-related inflammatory events involved 12 (1.9%) eyes in year 1 and five (0.8%) eyes each in years 2 and 3. One third of the inflammatory events occurred in the first 3 months. Mechanical events included two superior epithelial arcuate lesions and one case of bilateral contact lens papillary conjunctivitis in years 1 and 2. No subjects experienced microbial keratitis during the 3-year trial. Two subjects with events discontinued from the trial. Conclusions. These results show that the rate of contact lens adverse events occurring with lotrafilcon A is low in this cohort, with the highest likelihood occurring during the first 3 months of the study. There was a decrease in the rate of events during the later years of the study. Although clinicians should understand the likelihood of adverse inflammatory and mechanical events and their possible recurrence, the rate of these events may be lower in practice than previously reported.