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Association of Blood Pressure Lowering With Incident Dementia or Cognitive Impairment: A Systematic Review and Meta-analysis
Hughes D, Judge C, Murphy R, Loughlin E, Costello M, Whiteley W, et al.. JAMA, 2020-05-19
Topic: Risk, prevention and care in population studies
Importance The benefit of blood pressure lowering for the prevention of dementia or cognitive impairment is unclear. Objective To determine the association of blood pressure lowering with dementia or cognitive impairment. Data sources and study selection Search of PubMed, EMBASE, and CENTRAL for randomized clinical trials published from database inception through December 31, 2019, that evaluated the association of blood pressure lowering on cognitive outcomes. The control groups consisted of either placebo, alternative antihypertensive agents, or higher blood pressure targets. Data extraction and synthesis Data were screened and extracted independently by 2 authors. Random-effects meta-analysis models were used to report pooled treatment effects and CIs. Main outcomes and measures The primary outcome was dementia or cognitive impairment. The secondary outcomes were cognitive decline and changes in cognitive test scores. Results Fourteen randomized clinical trials were eligible for inclusion (96 158 participants), of which 12 reported the incidence of dementia (or composite of dementia and cognitive impairment [3 trials]) on follow-up and were included in the primary meta-analysis, 8 reported cognitive decline, and 8 reported changes in cognitive test scores. The mean (SD) age of trial participants was 69 (5.4) years and 40 617 (42.2%) were women. The mean systolic baseline blood pressure was 154 (14.9) mm Hg and the mean diastolic blood pressure was 83.3 (9.9) mm Hg. The mean duration of follow-up was 49.2 months. Blood pressure lowering with antihypertensive agents compared with control was significantly associated with a reduced risk of dementia or cognitive impairment (12 trials; 92 135 participants) (7.0% vs 7.5% of patients over a mean trial follow-up of 4.1 years; odds ratio [OR], 0.93 [95% CI, 0.88-0.98]; absolute risk reduction, 0.39% [95% CI, 0.09%-0.68%]; I2 = 0.0%) and cognitive decline (8 trials) (20.2% vs 21.1% of participants over a mean trial follow-up of 4.1 years; OR, 0.93 [95% CI, 0.88-0.99]; absolute risk reduction, 0.71% [95% CI, 0.19%-1.2%]; I2 = 36.1%). Blood pressure lowering was not significantly associated with a change in cognitive test scores. Conclusions and relevance In this meta-analysis of randomized clinical trials, blood pressure lowering with antihypertensive agents compared with control was significantly associated with a lower risk of incident dementia or cognitive impairment.
Key findings
- Results Fourteen randomized clinical trials were eligible for inclusion (96 158 participants), of which 12 reported the incidence of dementia (or composite of dementia and cognitive impairment [3 trials]) on follow-up and were included in the primary meta-analysis, 8 reported cognitive decline, and 8 reported changes in cognitive test scores.
- Blood pressure lowering with antihypertensive agents compared with control was significantly associated with a reduced risk of dementia or cognitive impairment (12 trials; 92 135 participants) (7.0% vs 7.5% of patients over a mean trial follow-up of 4.1 years; odds ratio [OR], 0.93 [95% CI, 0.88-0.98]; absolute risk reduction, 0.39% [95% CI, 0.09%-0.68%]; I2 = 0.0%) and cognitive decline (8 trials) (20.2% vs 21.1% of participants over a mean trial follow-up of 4.1 years; OR, 0.93 [95% CI, 0.88-0.99]; absolute risk reduction, 0.71% [95% CI, 0.19%-1.2%]; I2 = 36.1%).
- Blood pressure lowering was not significantly associated with a change in cognitive test scores.
- Conclusions and relevance In this meta-analysis of randomized clinical trials, blood pressure lowering with antihypertensive agents compared with control was significantly associated with a lower risk of incident dementia or cognitive impairment.
Why it matters
This meta-analysis of 14 randomized clinical trials with 96,158 participants found that blood pressure lowering with antihypertensive agents was significantly associated with a reduced risk of dementia or cognitive impairment. It supports treating high blood pressure as a way to lower dementia risk, though it does not show a treatment or cure for people who already have dementia.
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Study details
- Study designmeta-analysis
- Participants96,158
- Effect sizeOR 0.93 (95% CI 0.88-0.98); absolute risk reduction 0.39% over 4.1 years
- Evidence strengthHigh
Limitations
Trials were designed for cardiovascular outcomes with short follow-up; dementia often a secondary or composite endpoint; effect is modest in absolute terms.
How this study scored 85/100
Published in a top-tier journal, and it is a meta-analysis pooling many studies. We have no data on free to read, so that was left out: it earned 83 of the 98 points we could judge it on, which is 85 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 10 / 10 | Tier 1 — top-tier general journal (JAMA) |
| Journal's citation record | 4 / 4 | JAMA: journal h-index 1,011 (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 | 2 / 5 | 2020 — within 10 year(s) of the newest study here |
| Sample size | 4 / 4 | 96,158 participants |
| Effect reported | 3 / 3 | Effect reported with a statistic (interval, p-value, ratio or similar) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | A review of other studies — randomisation is not credited here |
| Times cited | 6 / 7 | Cited 470 times (OpenAlex, 2026-10-10) |
| Citations per year | 5 / 5 | 58.8 citations a year over 8 year(s) since 2020 |
| Impact for its field and year | 6 / 6 | Cited 40.8× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 26 other studies in this library |
| Still being cited | 4 / 4 | Cited 214 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 1 / 4 | Last-listed author Michelle D. Canavan: h-index 19 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | University of Edinburgh: institution h-index 1,378 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 4 institution(s) in 3 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 32427305) |
| Free to read | — / 2 | Access not recorded — left out of this score |
| Points | 83 / 98 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 83 of the 98 points we could judge it on is 85 out of 100. |
| Total | 85 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
Full text: free to read — PubMed Central lists this copy as free to read: the link above (checked 10 Oct 2026).
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. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Hughes, D., Judge, C., Murphy, R., Loughlin, E., Costello, M., Whiteley, W., et al. (2020). Association of Blood Pressure Lowering With Incident Dementia or Cognitive Impairment: A Systematic Review and Meta-analysis. JAMA. https://doi.org/10.1001/jama.2020.4249
Vancouver
Hughes D, Judge C, Murphy R, Loughlin E, Costello M, Whiteley W, et al. Association of Blood Pressure Lowering With Incident Dementia or Cognitive Impairment: A Systematic Review and Meta-analysis. JAMA. 2020. doi:10.1001/jama.2020.4249. PMID: 32427305.
BibTeX
@article{hughes2020-32427305,
author = {Hughes, D. and Judge, C. and Murphy, R. and Loughlin, E. and Costello, M. and Whiteley, W. and others},
title = {{Association of Blood Pressure Lowering With Incident Dementia or Cognitive Impairment: A Systematic Review and Meta-analysis}},
journal = {JAMA},
year = {2020},
doi = {10.1001/jama.2020.4249},
pmid = {32427305},
url = {https://doi.org/10.1001/jama.2020.4249}
}
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