Impact of aeroplane noise on mental and physical health: a quasi-experimental analysis.

OBJECTIVES: Historically, departures at New York City's LaGuardia airport flew over a large sports complex within a park. During the US Open tennis games, flights were diverted to fly over a heavily populated foreign-born neighbourhood for roughly 2 weeks out of the year so that the tennis match was not disturbed (the 'TNNIS' departure). In 2012, the use of the TNNIS departure became year-round to better optimise flight patterns around the metropolitan area. METHODS: We exploited exogenously induced spatial and temporal variation in flight patterns to examine difference-in-difference effects of this new exposure to aircraft noise on the health of individual residents in the community relative to individuals residing within a demographically similar community that was not impacted. We used individual-level Medicaid records, focusing on conditions associated with noise: sleep disturbance, psychological stress, mental illness, substance use, and cardiovascular disease. RESULTS: We found that increased exposure to aeroplane noise was associated with a significant increase in insomnia across all age groups, but particularly in children ages 5-17 (OR=1.64, 95% CI=1.12 to 2.39). Cardiovascular disease increased significantly both among 18-44-year-old (OR=1.45, 95% CI=1.41 to 1.49) and 45-64-year-old Medicaid recipients (OR=1.15, 95% CI=1.07 to 1.25). Substance use and mental health-related emergency department visits also increased. For ages 5-17,rate ratio (RR) was 4.11 (95% CI=3.28 to 5.16); for ages 18-44, RR was 2.46 (95% CI=2.20 to 2.76); and for ages 45-64, RR was 1.48 (95% CI=1.31 to 1.67). CONCLUSION: We find that increased exposure to aeroplane noise was associated with an increase in diagnosis of cardiovascular disease, substance use/mental health emergencies and insomnia among local residents.

The Trade-Off between Optimizing Flight Patterns and Human Health: A Case Study of Aircraft Noise in Queens, NY, USA.

Objectives: Airports in the U.S. have gradually been transitioning to automated flight systems. These systems generate new flight paths over populated areas. While they can improve flight efficiency, the increased noise associated with these novel flight patterns potentially pose serious health threats to the overflown communities. In this case study, we estimated the monetary benefits relative to health losses associated with one significant change in flight patterns at LaGuardia Airport, year-round use of "TNNIS Climb", which happened in 2012 as a result of flight automation in New York City. Prior to that, the use of the TNNIS Climb was limited to the U.S. Open tennis matches. Methods: We developed a decision-analytic model using Markov health states to compare the costs and quality-adjusted life years (QALYs) gained associated with the limited use of TNNIS (old status quo) and the year-round use of TNNIS (current status quo). The TNNIS Climb increases airplane noise to above 60 decibels (dB) over some of the most densely populated areas of the city. We used this increased exposure to noise as the basis for estimating ground-level health using data from sound monitors. The total costs (including both direct and indirect costs), QALYs, and the incremental cost-effectiveness ratio (ICER) were estimated for the limited versus the year-round use of the TNNIS Climb. Results: The incremental lifetime costs and QALYs per person exposed to noise associated with the limited versus the year-round use of TNNIS was $11,288, and 1.13, respectively. Therefore, the limited use of TNNIS had an ICER of $10,006/QALY gained relative to the year-round of TNNIS. Our analyses were robust to changes in assumptions and data inputs. Conclusions: Despite increases in efficiency, flight automation systems without a careful assessment of noise might generate flight paths over densely populated areas and cause serious health conditions for the overflown communities.

The Cost-Effectiveness of Lowering Permissible Noise Levels Around U.S. Airports.

Aircraft noise increases the risk of cardiovascular diseases and mental illness. The allowable limit for sound in the vicinity of an airport is 65 decibels (dB) averaged over a 24-h 'day and night' period (DNL) in the United States. We evaluate the trade-off between the cost and the health benefits of changing the regulatory DNL level from 65 dB to 55 dB using a Markov model. The study used LaGuardia Airport (LGA) as a case study. In compliance with 55 dB allowable limit of aircraft noise, sound insulation would be required for residential homes within the 55 dB to 65 dB DNL. A Markov model was built to assess the cost-effectiveness of installing sound insulation. One-way sensitivity analyses and Monte Carlo simulation were conducted to test uncertainty of the model. The incremental cost-effectiveness ratio of installing sound insulation for residents exposed to airplane noise from LGA was $11,163/QALY gained (95% credible interval: cost-saving and life-saving to $93,054/QALY gained). Changing the regulatory standard for noise exposure around airports from 65 dB to 55 dB comes at a very good value.

A practical femtosecond laser procedure for DLEK endothelial transplantation: cadaver eye histology and topography.

PURPOSE: The manual dissection technique for deep lamellar endothelial keratoplasty (DLEK) surgery is technically difficult and may not be smooth enough for consistently optimal postoperative vision. We evaluated the feasibility and efficacy of using a femtosecond laser to perform the dissections in the DLEK procedure. METHODS: The Intralase femtosecond laser (with standard LASIK surgery spot settings) was used to create a 9.4-mm wide, 400-microm deep lamellar pocket dissection and a 5.0-mm wide side cut near-exit incision in 10 "recipient" whole cadaver eyes and in 10 "donor" cadaver corneal-scleral caps mounted onto an artificial anterior chamber. Recipient and donor disks were resected with special scissors, and the donor tissue was transplanted using the small incision (5.0-mm) DLEK technique. Topography of the recipient eyes was measured pre- and postlaser dissection, and the recipient and donor tissues were sent for scanning electron microscopy (SEM) analysis of the smoothness of the dissections. RESULTS: Successful lamellar dissections were obtained in all tissues. The mean recipient topographic corneal curvature postoperatively was 43.3 +/- 1.7 diopters, which was not a significant change from the preoperative curvature of 44.0 +/- 0.8 diopters (P = 0.430). The mean recipient topographic astigmatism postoperatively was 1.7 +/- 0.8 diopters, which was not a significant change from the preoperative recipient astigmatism of 1.6 +/- 0.7 diopters (P = 0.426). Comparison of the histology of the laser-formed stromal dissections by scanning electron microscopy, however, did not appear significantly better than histology after manual DLEK dissections in either the recipient or the donor tissues. CONCLUSIONS: A femtosecond laser can create the lamellar dissections for the DLEK procedure, making this procedure easier and faster. As in the manual technique, corneal topography is unchanged by this surgery. More work will need to be done, however, to optimize the laser settings to provide even smoother interface surfaces.