The Role of Anti-inflammatory Agents in White Matter and Gray Matter Integrity in Older Age with Special Consideration of the Arthritis Patient

Abstract

A number of studies have indicated that individuals with arthritis have a decreased risk for Alzheimer's disease (AD). Inflammatory processes are implicated in the neurodegeneration associated with AD and the reduced risk associated with arthritis may be due to the anti-inflammatory (AI) drugs used by these individuals. The present project used magnetic resonance imaging (MRI) to assess the integrity of gray and white brain matter in AI users compared to controls not taking AIs. Thirty six female AI users were compared to thirty three controls. All participants underwent extensive neuropsychological testing. MRI scans included diffusion-weighted imaging, sensitive to the microstructural integrity of brain matter, high resolution anatomical imaging for the determination of brain volume, and T2 fluid attenuated inversion recovery (FLAIR) imaging, sensitive to white matter damage that is seen as hyperintense regions on this type of image. AI users showed increased brain integrity in the frontal lobes and in the corpus callosum, compared to controls indicated by diffusion imaging. Volumetric analysis indicated that AI users and controls have different relationships between brain volume and age. AI users showed greater brain volume than controls at higher ages, particularly in frontal and parietal brain regions, and in the cingulate. White matter hyperintensity volume did not differ between AI users and controls. Finally, the data indicated that non-steroidal anti-inflammatory drug (NSAID) use, but not methotrexate use, had a beneficial effect on cognitive function, particularly in the domain of memory function.