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Blood pressure lowering in patients without prior cerebrovascular disease for prevention of cognitive impairment and dementia
McGuinness B, Todd S, Passmore P, Bullock R.. The Cochrane database of systematic reviews, 2009-10-07
Topic: Risk, prevention and care in population studies
Main results Four trials including 15,936 hypertensive subjects were identified. The combined result of the four trials reporting incidence of dementia indicated no significant difference between treatment and placebo (236/7767 versus 259/7660, Odds Ratio (OR) = 0.89, 95% CI 0.74, 1.07) and there was considerable heterogeneity between the trials. The combined results from the three trials reporting change in Mini Mental State Examination (MMSE) did not indicate a benefit from treatment (Weighted Mean Difference (WMD) = 0.42, 95% CI 0.30, 0.53). Both systolic and diastolic blood pressure levels were reduced significantly in the three trials assessing this outcome (WMD = -10.22, 95% CI -10.78, -9.66 for systolic blood pressure, WMD = -4.28, 95% CI -4.58, -3.98 for diastolic blood pressure). Three trials reported adverse effects requiring discontinuation of treatment and the combined results indicated no significant difference (OR = 1.01, 95% CI 0.92, 1.11). There were significant problems identified with analysing the data, however, due to the number of patients lost to follow-up and the number of placebo patients who received active treatment. More robust results may be obtained by conducting a meta-analysis using individual patient data.
Key findings
- Main results Four trials including 15,936 hypertensive subjects were identified.
- The combined result of the four trials reporting incidence of dementia indicated no significant difference between treatment and placebo (236/7767 versus 259/7660, Odds Ratio (OR) = 0.89, 95% CI 0.74, 1.07) and there was considerable heterogeneity between the trials.
- The combined results from the three trials reporting change in Mini Mental State Examination (MMSE) did not indicate a benefit from treatment (Weighted Mean Difference (WMD) = 0.42, 95% CI 0.30, 0.53).
- Both systolic and diastolic blood pressure levels were reduced significantly in the three trials assessing this outcome (WMD = -10.22, 95% CI -10.78, -9.66 for systolic blood pressure, WMD = -4.28, 95% CI -4.58, -3.98 for diastolic blood pressure).
- Three trials reported adverse effects requiring discontinuation of treatment and the combined results indicated no significant difference (OR = 1.01, 95% CI 0.92, 1.11).
Why it matters
This meta-analysis of four trials in nearly 16,000 people with high blood pressure found no significant difference between blood pressure-lowering treatment and placebo in the incidence of dementia. It also found no benefit on Mini Mental State Examination scores, so it does not support blood pressure lowering as a way to prevent dementia in people without prior cerebrovascular disease.
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Study details
- Study designmeta-analysis
- Effect sizeOR = 1.01
- Evidence strengthHigh
How this study scored 67/100
Published in a leading specialty journal, and it is a meta-analysis pooling many studies. Scored zero for sample size and studied in people because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (The Cochrane database of systematic reviews) |
| Journal's citation record | 3 / 4 | Cochrane Database of Systematic Reviews: journal h-index 468 (OpenAlex, 2026-10-29) |
| Study design | 12 / 12 | A meta-analysis pooling many studies |
| Strength of evidence | 5 / 5 | Rated “high” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2009 — within 20 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 3 / 3 | Effect reported with a statistic (interval, p-value, ratio or similar) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | A review of other studies — randomisation is not credited here |
| Times cited | 6 / 7 | Cited 313 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 16.5 citations a year over 19 year(s) since 2009 |
| Impact for its field and year | 4 / 6 | Cited 15.5× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 24 other studies in this library |
| Still being cited | 1 / 4 | Cited 11 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Roger Alan Bullock: h-index 53 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Queen's University Belfast: institution h-index 712 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 19821318) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 67 / 100 | — |
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Read the original
- DOI: 10.1002/14651858.cd004034.pub3
- PubMed: 19821318
- Original source →
- Free full text: PubMed Central →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
McGuinness, B., Todd, S., Passmore, P., & Bullock, R. (2009). Blood pressure lowering in patients without prior cerebrovascular disease for prevention of cognitive impairment and dementia. The Cochrane database of systematic reviews. https://doi.org/10.1002/14651858.cd004034.pub3
Vancouver
McGuinness B, Todd S, Passmore P, Bullock R. Blood pressure lowering in patients without prior cerebrovascular disease for prevention of cognitive impairment and dementia. The Cochrane database of systematic reviews. 2009. doi:10.1002/14651858.cd004034.pub3. PMID: 19821318.
BibTeX
@article{mcguinness2009-19821318,
author = {McGuinness, B. and Todd, S. and Passmore, P. and Bullock, R.},
title = {{Blood pressure lowering in patients without prior cerebrovascular disease for prevention of cognitive impairment and dementia}},
journal = {The Cochrane database of systematic reviews},
year = {2009},
doi = {10.1002/14651858.cd004034.pub3},
pmid = {19821318},
url = {https://doi.org/10.1002/14651858.cd004034.pub3}
}
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