Cognitively Unimpaired HIV+ Participants Do Not Have Increased 11 C-PiB: A Case Control Study

1. Cognitively Unimpaired HIV+ Participants Do Not Have Increased 11C-PiB: A Case Control Study D. Clifford, M.Teshome, C. Xiong, A. Fagan, D. Holtzman, J. Morris, M. Mintun, J. Christensen, P. Aldea, J. Taylor, B. Ances Washington University in St. Louis, St. Louis, Missouri, USA • Low CSF amyloidβ1-42 typical of Alzheimer disease (AD) has been reported in HIV patients with cognitive impairment • 11C Pittsburgh Compound B (PIB) labels fibrillaramyloid in the brain that is found in AD brains routinely with low CSF AB42 • Reports of neuropathology of HIV patients are mixed with regard to amyloid and tau labeling, but typical AD path is not usually seen • PIB scans were performed on cognitively normal 10 HIV+ patients, 4 of whom had low CSF AB42 • Cognitively normal community controls were also scanned with PIB Background Experiment

2. Cognitively Unimpaired HIV+ Participants Do Not Have Increased 11C-PiB: A Case Control Study D. Clifford, M.Teshome, C. Xiong, A. Fagan, D. Holtzman, J. Morris, M. Mintun, J. Christensen, P. Aldea, J. Taylor, B. Ances Washington University in St. Louis, St. Louis, Missouri, USA • Low CSF amyloidβ1-42 typical of Alzheimer disease (AD) has been reported in HIV patients with cognitive impairment • 11C Pittsburgh Compound B (PIB) labels fibrillaramyloid in the brain that is found in AD brains routinely with low CSF AB42 • Reports of neuropathology of HIV patients are mixed with regard to amyloid and tau labeling, but typical AD path is not usually seen • PIB scans were performed on cognitively normal 10 HIV+ patients, 4 of whom had low CSF AB42 • Cognitively normal community controls were also scanned with PIB Background Experiment

3. Cognitively Unimpaired HIV+ Participants Do Not Have Increased 11C-PiB: A Case Control Study D. Clifford, M.Teshome, C. Xiong, A. Fagan, D. Holtzman, J. Morris, M. Mintun, J. Christensen, P. Aldea, J. Taylor, B. Ances Washington University in St. Louis, St. Louis, Missouri, USA • Low CSF amyloidβ1-42 typical of Alzheimer disease (AD) has been reported in HIV patients with cognitive impairment • 11C Pittsburgh Compound B (PIB) labels fibrillaramyloid in the brain that is found in AD brains routinely with low CSF AB42 • Reports of neuropathology of HIV patients are mixed with regard to amyloid and tau labeling, but typical AD path is not usually seen • PIB scans were performed on cognitively normal 10 HIV+ patients, 4 of whom had low CSF AB42 • Cognitively normal community controls were also scanned with PIB Background Experiment

4. Cognitively Unimpaired HIV+ Participants Do Not Have Increased 11C-PiB: A Case Control Study D. Clifford, M.Teshome, C. Xiong, A. Fagan, D. Holtzman, J. Morris, M. Mintun, J. Christensen, P. Aldea, J. Taylor, B. Ances Washington University in St. Louis, St. Louis, Missouri, USA • Low CSF amyloidβ1-42 typical of Alzheimer disease (AD) has been reported in HIV patients with cognitive impairment • 11C Pittsburgh Compound B (PIB) labels fibrillaramyloid in the brain that is found in AD brains routinely with low CSF AB42 • Reports of neuropathology of HIV patients are mixed with regard to amyloid and tau labeling, but typical AD path is not usually seen • PIB scans were performed on cognitively normal 10 HIV+ patients, 4 of whom had low CSF AB42 • Cognitively normal community controls were also scanned with PIB Background Experiment

5. Cognitively Unimpaired HIV+ Participants Do Not Have Increased 11C-PiB: A Case Control Study D. Clifford, M.Teshome, C. Xiong, A. Fagan, D. Holtzman, J. Morris, M. Mintun, J. Christensen, P. Aldea, J. Taylor, B. Ances Washington University in St. Louis, St. Louis, Missouri, USA • Low CSF amyloidβ1-42 typical of Alzheimer disease (AD) has been reported in HIV patients with cognitive impairment • 11C Pittsburgh Compound B (PIB) labels fibrillaramyloid in the brain that is found in AD brains routinely with low CSF AB42 • Reports of neuropathology of HIV patients are mixed with regard to amyloid and tau labeling, but typical AD path is not usually seen • PIB scans were performed on cognitively normal 10 HIV+ patients, 4 of whom had low CSF AB42 • Cognitively normal community controls were also scanned with PIB Background Experiment

9. Conclusions / Discussion • Further studies of cognitively impaired HIV+ are needed, as well as studies of HIV+ subjects who have Alzheimer’s disease pathology • Longitudinal study may be required since low CSF AB42 levels might precede brain amyloid deposition • Alternative imaging technique may be required to detect intraneuronalamyloid which may be important to HIV+ amyloiddysmetabolism • Evaluation of older subjects may be critical if disease duration and age are important interacting factors • Cognitively unimpaired HIV+ participants, even with low CSF AB42 do not have imaging findings of fibrillaramyloid deposition typical of Alzheimer disease • 11 C Pittsburgh Compound B PET imaging may help distinguish early Alzheimer disease from HIV associated neurocognitive disorder (HAND) • The biology of low CSF AB42 in HAND is likely to differ from that of AD, but amyloid metabolism remains a rational target for investigation in understanding HAND