Cerebrovascular reactivity and cognitive decline in patients with Alzheimer disease.
OBJECTIVE
The aim of this study was to explore the possible contribution of alterations in cerebral hemodynamics to the evolution of cognitive impairment in patients with Alzheimer disease (AD).


METHODS
Fifty-three patients with AD were investigated. The evolution of cognitive decline over 12 months was evaluated by means of changes in Mini Mental State Examination (MMSE) and AD Assessment Scale for Cognition (ADAS-Cog) scores. Demographic characteristics, vascular risk profile, pharmacological treatment, and presence of white matter lesions were assessed at entry. Further, a basal evaluation of cerebrovascular reactivity to hypercapnia was measured with transcranial Doppler ultrasonography using the breath-holding index (BHI).


RESULTS
Of all the variables considered, both MMSE and ADAS-Cog changes had the highest correlation with BHI, followed by age and diabetes. After subdividing both cognitive measures reductions into bigger and smaller-than-average decline (2 points for MMSE; 5 points for ADAS-Cog), multiple logistic regression indicated BHI as the sole significant predictor of cognitive decline.


CONCLUSIONS
These results show an association between impaired cerebral microvessels functionality and unfavorable evolution of cognitive function in patients with AD. Further research is needed to fully establish whether altered cerebral hemodynamics may be considered an independent factor in sustaining cognitive decline progression or an effect of pathological processes involved in AD.
Silvestrini
Mauro
M
Neurological Clinic, Polytechnic University of Marche, Ancona, Italy. masilvestrini@libero.it
Pasqualetti
Patrizio
P
Baruffaldi
Roberto
R
Bartolini
Marco
M
Handouk
Yasmin
Y
Matteis
Maria
M
Moffa
Filomena
F
Provinciali
Leandro
L
Vernieri
Fabrizio
F
D000368:Aged; D000375:Aging; D000544:Alzheimer Disease / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000523:psychology*; D002560:Cerebrovascular Circulation; D003071:Cognition; D048909:Diabetes Complications; D018450:Disease Progression; D005260:Female; D006439:Hemodynamics; D006801:Humans; D016015:Logistic Models; D008297:Male; D008833:Microcirculation; D011569:Psychiatric Status Rating Scales; D015656:Respiratory Mechanics; D012720:Severity of Illness Index; D017585:Ultrasonography, Doppler, Transcranial