No abstract

Following the impressive results of the SPRINT study published in 2015 (1), international hypertension guideline committees have gradually updated their advice. In 2017 the American College of Cardiology and American Heart Association (ACC/AHA) were the first to do so (2), followed by the European Society of Cardiology and European Society of Hypertension (ESC/ESH) in 2018 (3), and most recently the National Institute for Health and Care Excellence (NICE), who published their 'Hypertension in Adults' guideline in August 2019 (4). These three influential guidelines will inform global practice, yet whilst agreeing on many points there are also important differences in their recommendations. Here we focus on the European perspective, introducing the headline changes and then asking how and why the NICE guidelines differ from those of the ESC/ESH.The ESC/ESH guidelines reiterate the importance of reducing blood pressure (BP) below 140/90mmHg for all patients but go further to suggest, where tolerated, that systolic blood pressure (SBP) for those aged under 65 should be reduced to between 120 and 129mmHg. The recommended treatment threshold was retained at an SBP of 140mmHg, and recommended treatment for people with diabetes if BP is ≥140/90mmHg but with a target of <130/80mmHg. In terms of treatment, ESC/ESH recommend a 3-step approach with single pill dual therapy if SBP is ≥150mmHg and a single pill triple therapy if this is insufficient to obtain control. ESC/ESH also advocate low dose spironolactone for resistant hypertension, where triple therapy is unsuccessful.

The 2011 NICE hypertension guideline (CG127) undertook a systematic review of the diagnostic accuracy of different blood pressure (BP) assessment methods to confirm the diagnosis of hypertension. The guideline also undertook a cost-utility analysis exploring the cost-effectiveness of the monitoring methods. A new systematic review was undertaken as part of the 2019 NICE hypertension guideline update (NG136). BP monitoring methods compared included Ambulatory BP, Clinic BP and Home BP. Ambulatory BP was the reference standard. The economic model from the 2011 guideline was updated with this new accuracy data. Home BP was more sensitive and specific than Clinic BP. Specificity improved more than sensitivity since the 2011 review. A higher specificity translates into fewer people requiring unnecessary treatment. A key interest was to compare Home BP and Ambulatory BP, and whether any improvement in Home BP accuracy would change the model results. Ambulatory BP remained the most cost-effective option in all age and sex subgroups. In all subgroups, Ambulatory BP was associated with lower costs than Clinic BP and Home BP. In all except one subgroup (females aged 40), Ambulatory BP was dominant. However, Ambulatory BP remained the most cost-effective option in 40-year-old females as the incremental cost-effectiveness ratio for Home BP versus Ambulatory BP was above the NICE £20,000 threshold. The new systematic review showed that the accuracy of both Clinic BP and Home BP has increased. However, Ambulatory BP remains the most cost-effective option to confirm a diagnosis of hypertension in all subgroups evaluated.

Antihypertensive drug treatment is cost-effective for adults at high risk of developing cardiovascular disease (CVD). However, the cost-effectiveness in people with stage 1 hypertension (140–159 mm Hg systolic blood pressure) at lower CVD risk remains unclear. The objective was to establish the 10-year CVD risk threshold where initiating antihypertensive drug treatment for primary prevention in adults, with stage 1 hypertension, becomes cost-effective. A lifetime horizon Markov model compared antihypertensive drug versus no treatment, using a UK National Health Service perspective. Analyses were conducted for groups ranging between 5% and 20% 10-year CVD risk. Health states included no CVD event, CVD and non-CVD death, and 6 nonfatal CVD morbidities. Interventions were compared using cost-per-quality-adjusted life-years. The base-case age was 60, with analyses repeated between ages 40 and 75. The model was run separately for men and women, and threshold CVD risk assessed against the minimum plausible risk for each group. Treatment was cost-effective at 10% CVD risk for both sexes (incremental cost-effectiveness ratio £10 017/quality-adjusted life-year [$14 542] men, £8635/QALY [$12 536] women) in the base-case. The result was robust in probabilistic and deterministic sensitivity analyses but was sensitive to treatment effects. Treatment was cost-effective for men regardless of age and women aged >60. Initiating treatment in stage 1 hypertension for people aged 60 is cost-effective regardless of 10-year CVD risk. For other age groups, it is also cost-effective to treat regardless of risk, except in younger women.