{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,11]],"date-time":"2026-10-11T04:21:42Z","timestamp":1791692502617,"version":"4.3.4"},"reference-count":46,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,5,4]],"date-time":"2024-05-04T00:00:00Z","timestamp":1714780800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Geriatrics"],"abstract":"<jats:p>Background: Cerebrovascular hemodynamic impairment has been reported in Alzheimer\u2019s 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: \u22127.80 cm\/s, 95%CI: \u221210.78 to \u22125.13, p &lt; 0.0001, I2 = 71.0%). Due to a significant Egger\u2019s test (t = 3.12, p = 0.008), a trim-and-fill analysis was performed, confirming the difference (MD: \u221211.05 cm\/s, 95%CI: \u201312.28 to \u22129.82, p &lt; 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 &lt; 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 &lt; 0.0001, I2: 84.5%), while the breath-holding index test results were significant lower (MD: \u22121.72, 95%CI: \u22122.53 to \u22120.91, p &lt; 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.<\/jats:p>","DOI":"10.3390\/geriatrics9030058","type":"journal-article","created":{"date-parts":[[2024,5,6]],"date-time":"2024-05-06T15:05:01Z","timestamp":1715007901000},"page":"58","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Cerebral Blood Flow in Alzheimer\u2019s Disease: A Meta-Analysis on Transcranial Doppler Investigations"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4559-1292","authenticated-orcid":false,"given":"Marco","family":"Zuin","sequence":"first","affiliation":[{"name":"Department of Translational Medicine, University of Ferrara, Azienda Ospedaliero-Universitaria S. Anna, 44124 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"De Vito","sequence":"additional","affiliation":[{"name":"Department of Neurology, Stroke Division, Azienda Ospedaliero-Universitaria S. Anna, 44124 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tommaso","family":"Romagnoli","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, University of Ferrara, Azienda Ospedaliero-Universitaria S. Anna, 44124 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michele","family":"Polastri","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, University of Ferrara, Azienda Ospedaliero-Universitaria S. Anna, 44124 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleonora","family":"Capatti","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, University of Ferrara, Azienda Ospedaliero-Universitaria S. Anna, 44124 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristiano","family":"Azzini","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, University of Ferrara, Azienda Ospedaliero-Universitaria S. Anna, 44124 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gloria","family":"Brombo","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, University of Ferrara, Azienda Ospedaliero-Universitaria S. Anna, 44124 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovanni","family":"Zuliani","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, University of Ferrara, Azienda Ospedaliero-Universitaria S. Anna, 44124 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1579","DOI":"10.1586\/ern.11.155","article-title":"Distinguishing Alzheimer\u2019s disease from other major forms of dementia","volume":"11","author":"Karantzoulis","year":"2011","journal-title":"Expert. Rev. 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