B R Ott1, W C Heindel, Z Tan, R B Noto. 1. Department of Clinical Neurosciences, Memorial Hospital of Rhode Island, 111 Brewster St, Pawtucket, RI 02860, USA. Brian_Ott@mhri.org
Abstract
OBJECTIVE: To define the pathophysiologic substrate of gender differences in cognition and behavior in Alzheimer's disease (AD). DESIGN: Hemispheric regional cerebral blood flow (rCBF) was studied in a consecutive series of dementia patients using single photon emission computed tomography (SPECT). PARTICIPANTS: Subjects included 300 outpatients who were studied with SPECT as part of a diagnostic evaluation for degenerative dementia or memory disorder. METHOD: Based on qualitative descriptions by a radiologist, subjects were classified as having unilateral left, unilateral right, bilateral, or no perfusion defects. Semiquantitative analysis of SPECT images was also performed using region of interest radionuclide counts normalized to the cerebellum. RESULTS: Among 174 females and 126 males, unilateral left hemisphere defects were found more commonly in women than men (24% vs 10%; chi 2 = 9.4; P = .009). This observation was most significant for the 103 females and 62 males regarded as having probable AD (26% vs 8%; chi 2 = 9.3; P = .01). In a multiple regression model of clinical variables, shorter duration of disease and female gender were significant independent predictors of the unilateral left hemisphere pattern among those with probable AD. Age, family history, education, handedness, and severity of cognitive impairment were not significant contributors. CONCLUSIONS: Women with AD exhibit greater heterogeneity in rCBF than men. Asymmetry in rCBF occurs more often in women. In some cases, this is related to relative preservation of right hemisphere function in women.
OBJECTIVE: To define the pathophysiologic substrate of gender differences in cognition and behavior in Alzheimer's disease (AD). DESIGN: Hemispheric regional cerebral blood flow (rCBF) was studied in a consecutive series of dementiapatients using single photon emission computed tomography (SPECT). PARTICIPANTS: Subjects included 300 outpatients who were studied with SPECT as part of a diagnostic evaluation for degenerative dementia or memory disorder. METHOD: Based on qualitative descriptions by a radiologist, subjects were classified as having unilateral left, unilateral right, bilateral, or no perfusion defects. Semiquantitative analysis of SPECT images was also performed using region of interest radionuclide counts normalized to the cerebellum. RESULTS: Among 174 females and 126 males, unilateral left hemisphere defects were found more commonly in women than men (24% vs 10%; chi 2 = 9.4; P = .009). This observation was most significant for the 103 females and 62 males regarded as having probable AD (26% vs 8%; chi 2 = 9.3; P = .01). In a multiple regression model of clinical variables, shorter duration of disease and female gender were significant independent predictors of the unilateral left hemisphere pattern among those with probable AD. Age, family history, education, handedness, and severity of cognitive impairment were not significant contributors. CONCLUSIONS:Women with AD exhibit greater heterogeneity in rCBF than men. Asymmetry in rCBF occurs more often in women. In some cases, this is related to relative preservation of right hemisphere function in women.