Choroidal Thickness Profiles in Myopic Eyes of Young Adults in the Correction of Myopia Evaluation Trial Cohort

PurposeTo examine the relationship of choroidal thickness with axial length (AL) and myopia in young adult eyes in the ethnically diverse Correction of Myopia Evaluation Trial (COMET) cohort.DesignCross-sectional, multicenter study.MethodsIn addition to measures of myopia by cycloplegic autorefraction and AL by A-scan ultrasonography, participants underwent optical coherence tomography imaging of the choroid in both eyes at their last visit (14 years after baseline). Using digital calipers, 2 independent readers measured choroidal thickness in the right eye (left eye if poor quality; n = 37) at 7 locations: fovea and 750, 1500, and 2250 μm nasal (N) and temporal (T) to the fovea.ResultsChoroidal thickness measurements were available from 294 of 346 (85%) imaged participants (mean age: 24.3 ± 1.4 years; 44.9% male) with mean myopia of -5.3 ± 2.0 diopters and mean AL of 25.5 ± 1.0 mm. Overall, choroidal thickness varied by location (P < .0001) and was thickest at the fovea (273.8 ± 70.9 μm) and thinnest nasally (N2250, 191.5 ± 69.3 μm). Multivariable analyses showed significantly thinner choroids in eyes with more myopia and longer AL at all locations except T2250 (P ≤ .001) and presence of peripapillary crescent at all locations except T1500 and T2250 (P ≤ .0001). Choroidal thickness varied by ethnicity at N2250 (P < .0001), with Asians having the thinnest and African Americans the thickest choroids.ConclusionChoroids are thinner in longer, more myopic young adult eyes. The thinning was most prominent nasally and in eyes with a crescent. In the furthest nasal location, ethnicity was associated with choroidal thickness. The findings suggest that choroidal thickness should be evaluated, especially in the nasal regions where myopic degenerations are most commonly seen clinically

Effect of Noninvasive Respiratory Strategies on Intubation or Mortality Among Patients With Acute Hypoxemic Respiratory Failure and COVID-19: The RECOVERY-RS Randomized Clinical Trial.

Importance Continuous positive airway pressure (CPAP) and high-flow nasal oxygen (HFNO) have been recommended for acute hypoxemic respiratory failure in patients with COVID-19. Uncertainty exists regarding the effectiveness and safety of these noninvasive respiratory strategies. Objective To determine whether either CPAP or HFNO, compared with conventional oxygen therapy, improves clinical outcomes in hospitalized patients with COVID-19-related acute hypoxemic respiratory failure. Design, Setting, and Participants A parallel group, adaptive, randomized clinical trial of 1273 hospitalized adults with COVID-19-related acute hypoxemic respiratory failure. The trial was conducted between April 6, 2020, and May 3, 2021, across 48 acute care hospitals in the UK and Jersey. Final follow-up occurred on June 20, 2021. Interventions Adult patients were randomized to receive CPAP (n = 380), HFNO (n = 418), or conventional oxygen therapy (n = 475). Main Outcomes and Measures The primary outcome was a composite of tracheal intubation or mortality within 30 days. Results The trial was stopped prematurely due to declining COVID-19 case numbers in the UK and the end of the funded recruitment period. Of the 1273 randomized patients (mean age, 57.4 [95% CI, 56.7 to 58.1] years; 66% male; 65% White race), primary outcome data were available for 1260. Crossover between interventions occurred in 17.1% of participants (15.3% in the CPAP group, 11.5% in the HFNO group, and 23.6% in the conventional oxygen therapy group). The requirement for tracheal intubation or mortality within 30 days was significantly lower with CPAP (36.3%; 137 of 377 participants) vs conventional oxygen therapy (44.4%; 158 of 356 participants) (absolute difference, -8% [95% CI, -15% to -1%], P = .03), but was not significantly different with HFNO (44.3%; 184 of 415 participants) vs conventional oxygen therapy (45.1%; 166 of 368 participants) (absolute difference, -1% [95% CI, -8% to 6%], P = .83). Adverse events occurred in 34.2% (130/380) of participants in the CPAP group, 20.6% (86/418) in the HFNO group, and 13.9% (66/475) in the conventional oxygen therapy group. Conclusions and Relevance Among patients with acute hypoxemic respiratory failure due to COVID-19, an initial strategy of CPAP significantly reduced the risk of tracheal intubation or mortality compared with conventional oxygen therapy, but there was no significant difference between an initial strategy of HFNO compared with conventional oxygen therapy. The study may have been underpowered for the comparison of HFNO vs conventional oxygen therapy, and early study termination and crossover among the groups should be considered when interpreting the findings. Trial Registration isrctn.org Identifier: ISRCTN16912075