Cerebral Blood Flow in Alzheimer's Disease: A Meta-Analysis on Transcranial Doppler Investigations
- PMID: 38804315
- PMCID: PMC11130854
- DOI: 10.3390/geriatrics9030058
Cerebral Blood Flow in Alzheimer's Disease: A Meta-Analysis on Transcranial Doppler Investigations
Abstract
Background: Cerebrovascular hemodynamic impairment has been reported in Alzheimer's disease (AD). We performed a systematic review and meta-analysis to investigate changes in cerebral blood flow (CBF) in AD patients.
Methods: Data were obtained by searching MEDLINE and Scopus for all investigations published between 1 January 2011 and 1 November 2021, comparing the cerebrovascular hemodynamic between AD patients and cognately healthy age-matched controls, using transcranial Doppler (TCD) ultrasound.
Results: Twelve studies, based on 685 patients [395 with AD and 290 age-matched cognitively healthy controls, with a mean age of 71.5 and 72.1 years, respectively] were included in the analysis. A random effect model revealed that AD patients, in the proximal segments of the middle cerebral artery (MCA), have a significantly lower CBF velocity, compared to controls (MD: -7.80 cm/s, 95%CI: -10.78 to -5.13, p < 0.0001, I2 = 71.0%). Due to a significant Egger's test (t = 3.12, p = 0.008), a trim-and-fill analysis was performed, confirming the difference (MD: -11.05 cm/s, 95%CI: -12.28 to -9.82, p < 0.0001). Meta-regression analysis demonstrated that the mean CBF at the proximal MCA was directly correlated with arterial hypertension (p = 0.03) and MMSE score (p < 0.001), but inversely correlated with age (p = 0.01). In AD patients, the pulsatility index was significantly higher compared to controls (MD: 0.16, 95%CI: 0.07 to 0.25, p < 0.0001, I2: 84.5%), while the breath-holding index test results were significant lower (MD: -1.72, 95%CI: -2.53 to -0.91, p < 0.001, I2: 85.4%).
Conclusions: AD patients have a significant impairment in relation to their cerebrovascular perfusion, suggesting that cerebrovascular hemodynamic deterioration, evaluated using TCD, may be a useful diagnostic tool.
Keywords: Alzheimer’s Disease; cerebral flow; transcranial Doppler.
Conflict of interest statement
The authors declare no conflicts of interest.
Figures
References
-
- Clark L.R., Berman S.E., Rivera-Rivera L.A., Hoscheidt S.M., Darst B.F., Engelman C.D., Rowley H.A., Carlsson C.M., Asthana S., Turski P., et al. Macrovascular and microvascular cerebral blood flow in adults at risk for Alzheimer’s disease. Alzheimers Dement. 2017;7:48–55. doi: 10.1016/j.dadm.2017.01.002. - DOI - PMC - PubMed
-
- Hughes T.M., Wagenknecht L.E., Craft S., Mintz A., Heiss G., Palta P., Wong D., Zhou Y., Knopman D., Mosley T.H., et al. Arterial stiffness and dementia pathology: Atherosclerosis Risk in Communities (ARIC)-PET Study. Neurology. 2018;90:e1248–e1256. doi: 10.1212/WNL.0000000000005259. - DOI - PMC - PubMed
Publication types
LinkOut - more resources
Full Text Sources
