Trends in Myopia and High Myopia from 1966 to 2019 in Olmsted County, Minnesota.

PURPOSE: To investigate the prevalence of myopia and high myopia in Olmsted County, Minnesota, from 1966 to 2019. DESIGN: Retrospective, cross-sectional, trend study. METHODS: Manifest refractions or lens prescription were converted to spherical equivalent (SE) to estimate the prevalence of adult myopia and high myopia. Age, sex, race, and visual acuity were recorded. Subjects with an SE of -0.5 diopters (D) or less were considered to have myopia; those with an SE of -6.0 D or less were considered to have high myopia. Exclusion criteria included visually significant cataract, pseudophakia, prior refractive surgery, or age less than 18 years. RESULTS: Among 81,706 sampled subjects, the myopia prevalence increased from 33.9% (95% CI, 31.1-36.8) in the 1960s to 57.1% (95% CI, 56.6-57.6) in the 2010s (P < .001). The high myopia prevalence increased from 2.8% (95% CI, 1.95-3.98) in the 1960s to 8.3% (95% CI, 8.08-8.62) in the 2010s (P < .001). Both male (32.0%-55.1%, P < .001) and female (40.6%-58.5%, P < .001) subjects experienced increasing myopia prevalence from the 1960s to the 2010s; both male (2.6%-7.4%, P < .001) and female (3.4%-9.1%, P < .001) subjects also had higher high myopia prevalence rates from the 1960s through the 2010s. Increasing myopia and high myopia prevalence was detected by decade in nearly all age groups (excluding 18- to 24-year-old high myopia subjects). White and Asian subjects had the highest myopia prevalence, whereas Black subjects had the lowest. From the 2000s to the 2010s, White (53.3%-57.0%, P < .001) and Black (41.0%-47.0%, P = .001) subjects had significant increases in myopia prevalence. The mean SE decreased from the 1960s (-0.42 D; 95% CI, -0.59 to +2.49) to the 2010s (-1.85 D; 95% CI, -1.88 to +2.96) (P < .001). CONCLUSIONS: From 1966 to 2019 in Olmsted County, Minnesota, there was a 68% and 199% increase in myopia and high myopia prevalence, respectively.

Aerosolized, Gas-Phase, Intravitreal Methotrexate Reduces Proliferative Vitreoretinopathy in a Randomized Trial in a Porcine Model.

Purpose: To determine the effectiveness of aerosol-delivered methotrexate (AD-MTx) in a large-animal (porcine) model of proliferative vitreoretinopathy (PVR). Design: Prospective, randomized, interventional, double-masked, controlled, large-animal study with predetermined clinical and histopathologic outcome criteria. Controls: Half of the pigs were randomly assigned to receive an identical volume of aerosol-delivered normal saline (AD-NS) using identical delivery systems and treatment intervals. Methods: Proliferative vitreoretinopathy was surgically induced in 16 pigs (8 males and 8 females), randomly assigned to receive 2 doses (group A) or 3 doses (group B) of either AD-MTx (1.6 mg/0.4 ml) or normal saline (AD-NS). Group A pigs were euthanized at week 2 (n = 8), and group B pigs were euthanized at week 3 (n = 8). Masked clinical PVR scores (0-6) by a vitreoretinal surgeon and histopathology PVR scores (0-8) by a masked ophthalmic pathologist were used to determine outcomes. Main Outcome Measures: The mean, combined clinical and histopathology scores (both anterior and posterior) were used to determine the overall treatment effect between the groups. Results: The mean masked score (± standard deviation) when all grading end points (clinical + histopathology) were combined was a mean of 8.0 ± 2.3 in the AD-MTx group versus a higher 9.9 ± 2.0 in the AD-NS control group (P = 0.05). The clinical score was 3.88 ± 1.2 in the AD-MTx group versus 4.63 ± 1.6 in the AD-NS group (P = 0.16). The histopathology score for anterior PVR was 2.5 ± 0.8 in the AD-MTx group versus 2.5 ± 0.5 in the AD-NS group (P = 0.50), and the posterior PVR was 1.63 ± 1.6 in the AD-MTx group versus 2.75 ± 1.3 in the AD-NS group (P = 0.07). When the frequency of methotrexate dosing in group A (2 doses) was compared with that in group B (3 doses), the mean score was 8.75 versus 9.13 (P = 0.38), respectively, suggesting an insignificant difference. Conclusions: After surgical induction of PVR in an aggressive, high-risk, large-animal model, AD-MTx reduced posterior PVR formation compared with AD-NS. Additional dosing at week 3 did not improve the outcomes. No difference in anterior PVR formation was noted with intervention. This novel drug delivery system has implications for PVR reduction and warrants further investigation. Financial Disclosures: Proprietary or commercial disclosure may be found after the references.