Intervention review

A review of health economic evidence related to the same review question was conducted in parallel with this review. For details, see the health economic review protocol for this NICE guideline.

Population: Adults (over 18 years) who are not on current pharmacological treatment for hypertension (minimum wash-out 4 weeks)

Stratify by:

• Presence or absence of type 2 diabetes
• Cardiovascular or blood pressure baseline risk

• Systolic blood pressure targets:

  • Below120
  • 120–129
  • 130–139 mmHg
  • 140–59 mmHg
  • 160 mmHg or above
• Diastolic blood pressure targets:

  • <80 mmHg
  • 80–84 mmHg
  • 85–89 mmHg
  • 90–94 mmHg
  • 95 mmHg or above

1. 5–9%
2. 10–14%
3. 15–19%
4. Above 20%

Compared against each other (comparing different blood pressure and/or cardiovascular risk thresholds)

Also within each other

All outcomes to be measured at a minimum of 12 months. Where multiple time points are reported within each study, the longest time point only will be extracted.

Critical

• All-cause mortality
• Health-related quality of life
• Stroke (ischaemic or haemorrhagic)
• Myocardial infarction

• Heart failure needing hospitalisation
• Vascular procedures (including lower limb, coronary and carotid artery procedures)
• Angina needing hospitalisation
• Side effect 1: Acute kidney injury
• Side effect 2: New onset diabetes
• Side effect 3: Treatment related admission
• Side effect 4: Hypotension (dizziness)
• [Combined cardiovascular disease outcomes in the absence of MI and stroke data]
• [Coronary heart disease outcome in the absence of MI data]

1. SRs (including IPD analyses) and RCTs that stratify or subgroup by baseline cardiovascular risk or blood pressure
2. Non-randomised studies that stratify by baseline cardiovascular risk or blood pressure

• Confounders that should be adjusted for:

  • age
  • prior CV event
  • smoking
  • sex
  • BP (CV risk)

• Treatment must be received for a minimum of 1 year in study
• Where an IPD meta-analysis is available that matches the protocol, this will be included and data published since will be presented separately. IPD meta-analysis is considered the highest quality evidence, therefore lower quality evidence will only be considered if it was published after the IPD.

• Non-comparative data where all participants start at the same treatment threshold (studies that do not stratify by 2 or more blood pressure or CV risk groups)
• Studies including participants with type 1 diabetes or chronic kidney disease (A3 [heavy proteinuria]) or A2 or above for participants with type 2 diabetes.
• Indirect populations with secondary causes of hypertension such as tumours or structural vascular defects (Conn’s adenoma, phaeochromocytoma, renovascular hypertension).
• Pregnant women.
• Children (under 18 years).

Duplicate screening, selection and analysis will be undertaken on this review.

A senior research fellow will undertake quality assurance prior to completion.

Pairwise meta-analyses were performed using Cochrane Review Manager (RevMan5).

GRADEpro was used to assess the quality of evidence for each outcome.

Endnote for bibliography, citations, sifting and reference management.

Medline, Embase, the Cochrane Library

Date cut off: 2000 (restrict to papers published after this date)

Language: Restrict to English only

Key papers:

Cochrane review (2017): http:​//onlinelibrary​.wiley.com/doi/10.1002/14651858​.CD010316.pub2/full

Standard study checklists were used to appraise individual studies critically. For details, please see section 6.2 of Developing NICE guidelines: the manual

The risk of bias across all available evidence was evaluated for each outcome using an adaptation of the ‘Grading of Recommendations Assessment, Development and Evaluation (GRADE) toolbox’ developed by the international GRADE working group http://www​.gradeworkinggroup.org/

A multidisciplinary committee developed the evidence review. The committee was convened by the National Guideline Centre (NGC) and chaired by Anthony Wierzbicki in line with section 3 of Developing NICE guidelines: the manual.

Staff from NGC undertook systematic literature searches, appraised the evidence, conducted meta-analysis and cost-effectiveness analysis where appropriate, and drafted the evidence review in collaboration with the committee. For details, please see Developing NICE guidelines: the manual.