Factors Associated with Changes in Brain Atrophy during a Three-Year Observation in Elderly Diabetic Patients: Effect of Renal Impairment on Hippocampal Atrophy.

BACKGROUND/AIMS: We conducted a 3-year longitudinal study concerning factors associated with changes in brain atrophy in elderly diabetic patients. METHODS: We evaluated hippocampal and global brain atrophy using automatic voxel-based morphometry of structural magnetic resonance images, 4 cognitive function tests, and cerebral small vessel disease (SVD) in 66 diabetic patients. RESULTS: During the 3-year follow-up, hippocampal and global brain atrophy advanced, and cognitive functions worsened. For changes in hippocampal atrophy, changes in estimated glomerular filtration rate (eGFR), albuminuria, and being an ApoE ε4 carrier were independent factors; change in the number of silent brain infarctions was an independent factor for changes in global brain atrophy. A significant association of changes in eGFR and albuminuria with hippocampal atrophy remained after adjusting for confounders including SVD. Both types of brain atrophy at baseline were significantly correlated with cognitive impairment at baseline and especially associated with changes in delayed word recall during the follow-up after adjusting for confounders. CONCLUSION: Changes in eGFR and albuminuria during follow-up were independent risk factors for hippocampal atrophy, which was associated with decline in delayed word recall, suggesting that management of chronic kidney disease may prevent the progression of hippocampal atrophy.

Local amplification of storm surge by Super Typhoon Haiyan in Leyte Gulf.

Typhoon Haiyan, which struck the Philippines in November 2013, was an extremely intense tropical cyclone that had a catastrophic impact. The minimum central pressure of Typhoon Haiyan was 895 hPa, making it the strongest typhoon to make landfall on a major island in the western North Pacific Ocean. The characteristics of Typhoon Haiyan and its related storm surge are estimated by numerical experiments using numerical weather prediction models and a storm surge model. Based on the analysis of best hindcast results, the storm surge level was 5-6 m and local amplification of water surface elevation due to seiche was found to be significant inside Leyte Gulf. The numerical experiments show the coherent structure of the storm surge profile due to the specific bathymetry of Leyte Gulf and the Philippines Trench as a major contributor to the disaster in Tacloban. The numerical results also indicated the sensitivity of storm surge forecast.