Meta-analysisindependent cross-checkabstract checked★ key study I-SYS-108 in-depth review
Lowering blood pressure saves lives
Blood pressure lowering for prevention of cardiovascular disease and death: a systematic review and meta-analysis.
Overview
Ettehad D et al.. Lancet 2016 · PMID 26724178 · DOI 10.1016/S0140-6736(15)01225-8
Each 10 mm Hg lower systolic pressure cut major heart and stroke events by 20% and deaths by 13%.
Does the study support the specific claim? No · Methodological quality: high
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Effects of lowering BP.
- How was the study done?
Meta-analysis of 123 RCTs.
- How many people, animals or samples were studied?
613,815 people.
- What was actually found?
Fewer events and deaths.
- How large was the observed effect?
RR 0.80 CVD; 0.87 death.
- What do the results mean in everyday life?
Medicines for high blood pressure prevent strokes and deaths.
- What are the study's limitations?
Relative effects.
- What does it say about Elawady's specific claim?
Contradicts 'zero medicine'.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Every drug class equally.
Scientific in-depth review
1. Full reference
- Authors
- Ettehad D et al.
- Journal
- Lancet
- Year
- 2016
- Identifier
- PMID 26724178 DOI 10.1016/S0140-6736(15)01225-8
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
NIHR and Oxford Martin School funding
2. Research question
Effects of blood pressure lowering on cardiovascular events and death
3. Study design and population
- Study design
- Meta-analysis – Systematic review and meta-analysis of large blood-pressure-lowering RCTs
- Population
Participants of 123 RCTs
- Country
International
- Period
1966-2015
- Sample size
123 studies, 613,815 participants
- Inclusion and exclusion criteria
RCTs with >=1000 patient-years per arm
4. Methods and endpoints
- Exposure / intervention
Blood-pressure-lowering treatment
- Comparator
Control/less intensive
- Endpoints
Major CVD, CHD, stroke, heart failure, renal failure, all-cause mortality
- Statistical methods
Fixed-effect meta-analysis; meta-regression
5. Actual results
- Results
Per 10 mm Hg systolic reduction: major CVD events RR 0.80 (0.77-0.83), CHD 0.83, stroke 0.73 (0.68-0.77), heart failure 0.72, all-cause mortality 0.87 (0.84-0.91); renal failure 0.95 (0.84-1.07). Risk of bias low in 113 trials.
- Absolute risks
not reported in abstract
- Authors' conclusion
Blood pressure lowering significantly reduces vascular risk across baseline levels and comorbidities.
6. Strengths
- Very large RCT evidence
- Low risk of bias
7. Weaknesses
- Absolute effects depend on baseline risk
8. Risk of bias
- Orienting tool
- AMSTAR 2
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- low
- Rationale
Systematic, RCT-based.
9. Assessment of the statistical interpretation
CI asymmetries due to 2-decimal rounding of narrow intervals.
10. Relevance to the specific claim
Shows that a laboratory/clinical marker (blood pressure) is causal: lowering it with medicines prevents events and death; refutes 'zero medicine' and 'markers are only signals'.
11. Independent contrary findings
12. Transferability to Germany and Europe
High.
13. Overall methodological judgement
High-certainty evidence against blanket rejection of medicines and of risk markers.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | high |
| Risk of bias | low |
| Precision of results | high |
| Directness | direct |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
15. Linked fact checks
- The system's life method is 'zero medicine': a life without any medicines at all. – Studies contradicting or limiting the claim
- Laboratory values (blood glucose, acetone, HDL/LDL, urea, creatinine, electrolytes) only indicate a change of the body's strategy under stress; there is no proof they cause symptoms, and linking them to the type of food is '100% wrong'. – Studies contradicting or limiting the claim
- The body heals itself if left alone: the human body was created healthy and has an unlimited capacity for self-healing unless burdened by harmful inputs. – Studies contradicting or limiting the claim