Cognition and Magnetic Resonance Imaging of Brain Inflammation in Obesity
Condition: Obesity
MeSH terms: Obesity
Study type: Interventional

Summary: 
      The rate of obesity in the United States is high and is a risk factor for concurrent
      cognitive impairment and, in late life, dementias such as Alzheimer's disease. In order to
      prevent or reduce cognitive impairment, the mechanism underlying the link between obesity and
      cognitive impairment must be understood. The current study aims to provide preliminary data
      on whether brain inflammation occurs in obesity and relates to cognitive deficits using
      magnetic resonance neuroimaging and cognitive testing. It is hypothesized that obese
      individuals will have greater brain inflammation and lower cognitive function compared to
      normal-weight individuals. Further, it is predicted that brain inflammation will relate to
      cognitive function and plasma indicators of inflammation in obese individuals.
    

Detailed description: 
      Initially, normal-weight or obese potential participants are screened by a phone interview
      that assesses medical history. Obtainment of informed consent and further screening occurs on
      the day of the study visit. Participants then undergo a 2 hour oral glucose tolerance test
      (OGTT) including blood draws for metabolic and inflammatory marker levels in plasma. Lunch is
      then provided. Participants are then administered 30 minute computer-based cognitive testing
      from the NIH Toolbox Cognition Battery. After cognitive testing, participants undergo 1.5
      hour magnetic resonance imaging (MRI) that includes structural, diffusion tensor, and
      functional MR imaging.
    

Intervention name(s): Oral glucose tolerance test; Cognitive testing; Magnetic resonance imaging
Intervention type(s): Procedure; Behavioral; Procedure
Intervention description(s): After 8 hours fasting overnight, an intravenous catheter is placed in the arm or hand for blood draws. Participants drink 75 grams of an oral glucose drink after baseline blood samples are drawn. More blood draws occur at 10, 20, 30, 60 and 120 min post-glucose drink.; For approximately 40 minutes, participants are assessed for cognitive function using computer-based tests available from the NIH Toolbox Cognitive Battery (Weintraub et al., 2013), including attention and executive functioning, episodic memory, working memory, language, processing speed, and immediate recall.; Magnetic resonance imaging (MRI) scans will be performed in a 3 Tesla MRI scanner over 1.5 hours. Participants will be asked to lay down flat on their backs and to try to stay still throughout the MRI scan. The participant will wear MRI-safe headphones to block out noise due to the MRI scans. Participant comfort will be verbally checked on throughout the scan and the participant will be provided with a 'squeeze ball' to signal the MRI technician that they want to get out of the scanner immediately.
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Intervention model description: This study employed a single group model in which participants with obesity and participants with normal-weight underwent magnetic resonance imaging, blood draws and cognitive assessment.
Masking: Double (Investigator, Outcomes Assessor)
Primary purpose: Other
Keywords: Obesity; Inflammation; Cognitive impairment; Neuroimaging; Magnetic resonance imaging