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OBJECTIVES: Evidence to support initiation of pharmacological treatment in patients with uncomplicated (low risk) mild hypertension is inconclusive. As such, clinical guidelines are contradictory and healthcare policy has changed regularly. The aim of this study was to determine the incidence of lifestyle advice and drug therapy in this population and whether secular trends were associated with policy changes. DESIGN: Longitudinal cohort study. SETTING: Primary care practices contributing to the Clinical Practice Research Datalink in England. PARTICIPANTS: Data were extracted from the linked electronic health records of patients aged 18-74 years, with stage 1 hypertension (blood pressure between 140/90 and 159/99 mm Hg), no cardiovascular disease (CVD) risk factors and no treatment, from 1998 to 2015. Patients exited if follow-up records became unavailable, they progressed to stage 2 hypertension, developed a CVD risk factor or received lifestyle advice/treatment. PRIMARY OUTCOME MEASURES: The association between policy changes and incidence of lifestyle advice or treatment, examined using an interrupted time-series analysis. RESULTS: A total of 108 843 patients were defined as having uncomplicated mild hypertension (mean age 51.9±12.9 years, 60.0% female). Patientsspent a median 2.6 years (IQR 0.9-5.5) in the study, after which 12.2% (95% CI 12.0% to 12.4%) were given lifestyle advice, 29.9% (95% CI 29.7% to 30.2%) were prescribed medication and 19.4% (95% CI 19.2% to 19.6%) were given both. The introduction of the quality outcomes framework (QOF) and subsequent changes to QOF indicators were followed by significant increases in the incidence of lifestyle advice. Treatment prescriptions decreased slightly over time, but were not associated with policy changes. CONCLUSIONS: Despite secular trends that accord with UK guidance, many patients are still prescribed treatment for mild hypertension. Adequately powered studies are needed to determine if this is appropriate.

BackgroundEthnicity, along with a variety of genetic and environmental factors, is thought to influence the efficacy of antihypertensive therapies. Current UK guidelines use a “black versus white” approach; in doing so, they ignore the United Kingdom's largest ethnic minority: Asians from South Asia.Study designThe primary purpose of the AIM-HY INFORM trial is to identify potential differences in response to antihypertensive drugs used as mono- or dual therapy on the basis of self-defined ethnicity. A multicenter, prospective, open-label, randomized study with 2 parallel, independent trial arms (mono- and dual therapy), AIM-HY INFORM plans to enroll a total of 1,320 patients from across the United Kingdom. Those receiving monotherapy (n = 660) will enter a 3-treatment (amlodipine 10 mg od; lisinopril 20 mg od; chlorthalidone 25 mg od), 3-period crossover, lasting 24 weeks, whereas those receiving dual therapy (n = 660) will enter a 4-treatment (amlodipine 5 mg od and lisinopril 20 mg od; amlodipine 5 mg od and chlorthalidone 25 mg od; lisinopril 20 mg od and chlorthalidone 25 mg od; amiloride 10 mg od and chlorthalidone 25 mg od), 4-period crossover, lasting 32 weeks. Equal numbers of 3 ethnic groups (white, black/black British, and Asian/Asian British) will ultimately be recruited to each of the trial arms (ie, 220 participants per ethnic group per arm). Seated, automated, unattended, office, systolic blood pressure measured 8 weeks after each treatment period begins will serve as the primary outcome measure.ConclusionAIM-HY INFORM is a prospective, open-label, randomized trial which aims to evaluate first- and second-line antihypertensive therapies for multiethnic populations.

Importance: Evidence to support initiation of pharmacological treatment in patients with low-risk mild hypertension is inconclusive, with previous trials underpowered to demonstrate benefit. Clinical guidelines across the world are contradictory. Objective: Use electronic health records to examine whether treatment is safe and effective at reducing the risk of mortality and cardiovascular disease in low-risk mild hypertensives. Design: Longitudinal cohort study. Setting: Linked electronic health records from primary and secondary care in England. Participants: Data were extracted from patients in the Clinical Practice Research Datalink, between 1998-2015, aged 18-74 years, with mild hypertension (untreated blood pressure between 140/90-159/99mmHg) and no previous treatment. Anyone with a history of cardiovascular disease (CVD) or CVD risk factors was excluded. Patients exited the cohort if follow-up records became unavailable or they experienced an outcome of interest. Exposures: Prescription of antihypertensive medication. Propensity scores predicting likelihood of treatment were constructed using a logistic regression model. Individuals treated within 12 months of diagnosis were matched to untreated patients by propensity score using the nearest neighbour method. Main Outcome(s) and Measure(s): The rate of mortality, cardiovascular disease and adverse events in patients prescribed antihypertensive treatment at baseline, compared to those not, using Cox regression. Results: A total of 19,143 treated patients (mean age 54.7±11.8 years, 55.9% female) were matched to 19,143 similar untreated patients. During a median follow-up period of 5.8 years, no evidence of an association was found between antihypertensive treatment and mortality (HR 1.02, 95%CI 0.88-1.17), CVD (HR 1.09, 95%CI 0.95-1.25) or any individual cardiovascular disease endpoints. Treatment was associated with an increased risk of adverse events including hypotension (HR 1.69, 95%CI 1.30-2.20, NNH10=41), syncope (HR 1.28, 95%CI 1.10-1.50, NNH10=35), electrolyte abnormalities (HR 1.72, 95%CI 1.12-2.65, NNH10=111) and acute kidney injury (HR 1.37, 95%CI 1.00-1.88, NNH10=91).

Supplemental Digital Content is available in the text., Patients often have lower (white coat effect) or higher (masked effect) ambulatory/home blood pressure readings compared with clinic measurements, resulting in misdiagnosis of hypertension. The present study assessed whether blood pressure and patient characteristics from a single clinic visit can accurately predict the difference between ambulatory/home and clinic blood pressure readings (the home–clinic difference). A linear regression model predicting the home–clinic blood pressure difference was derived in 2 data sets measuring automated clinic and ambulatory/home blood pressure (n=991) using candidate predictors identified from a literature review. The model was validated in 4 further data sets (n=1172) using area under the receiver operator characteristic curve analysis. A masked effect was associated with male sex, a positive clinic blood pressure change (difference between consecutive measurements during a single visit), and a diagnosis of hypertension. Increasing age, clinic blood pressure level, and pulse pressure were associated with a white coat effect. The model showed good calibration across data sets (Pearson correlation, 0.48–0.80) and performed well-predicting ambulatory hypertension (area under the receiver operator characteristic curve, 0.75; 95% confidence interval, 0.72–0.79 [systolic]; 0.87; 0.85–0.89 [diastolic]). Used as a triaging tool for ambulatory monitoring, the model improved classification of a patient’s blood pressure status compared with other guideline recommended approaches (93% [92% to 95%] classified correctly; United States, 73% [70% to 75%]; Canada, 74% [71% to 77%]; United Kingdom, 78% [76% to 81%]). This study demonstrates that patient characteristics from a single clinic visit can accurately predict a patient’s ambulatory blood pressure. Usage of this prediction tool for triaging of ambulatory monitoring could result in more accurate diagnosis of hypertension and hence more appropriate treatment.

OBJECTIVE: To prospectively validate the Predicting Out-of-OFfice Blood Pressure (PROOF-BP) algorithm to triage patients with suspected high blood pressure for ambulatory blood pressure monitoring (ABPM) in routine clinical practice. DESIGN: Prospective observational cohort study. SETTING: 10 primary care practices and one hospital in the UK. PARTICIPANTS: 887 consecutive patients aged 18 years or more referred for ABPM in routine clinical practice. All underwent ABPM and had the PROOF-BP applied. MAIN OUTCOME MEASURES: The main outcome was the proportion of participants whose hypertensive status was correctly classified using the triaging strategy compared with the reference standard of daytime ABPM. Secondary outcomes were the sensitivity, specificity, and area under the receiver operator characteristic curve (AUROC) for detecting hypertension. RESULTS: The mean age of participants was 52.8 (16.2) years. The triaging strategy correctly classified hypertensive status in 801 of the 887 participants (90%, 95% confidence interval 88% to 92%) and had a sensitivity of 97% (95% confidence interval 96% to 98%) and specificity of 76% (95% confidence interval 71% to 81%) for hypertension. The AUROC was 0.86 (95% confidence interval 0.84 to 0.89). Use of triaging, rather than uniform referral for ABPM in routine practice, would have resulted in 435 patients (49%, 46% to 52%) being referred for ABPM and the remainder managed on the basis of their clinic measurements. Of these, 69 (8%, 6% to 10%) would have received treatment deemed unnecessary had they received ABPM. CONCLUSIONS: In a population of patients referred for ABPM, this new triaging approach accurately classified hypertensive status for most, with half the utilisation of ABPM compared with usual care. This triaging strategy can therefore be recommended for diagnosis or management of hypertension in patients where ABPM is being considered, particularly in settings with limited resources.

SPIRIT 2013 Checklist: Recommended items to address in a clinical trial protocol and related documents. (DOC 137 kb)