Prevention of Atrial Fibrillation by Intensive Antihypertensive Treatment.

Because of increasing longevity, atrial fibrillation has become a frequent cardiac arrhythmia in clinical practice and a huge burden on healthcare systems in both high and low/middle-income countries. According to the recent data from the Global Heath Data Exchange database, the estimated worldwide incidence and prevalence for 2017 were 403 per million inhabitants and 0.5% of the total population, respectively, being 31% and 33% more than 20 years ago in 1997. In addition, the projected absolute disease burden of atrial fibrillation may further increase by 60% in 2050. These estimations and projections were similar to the results of several earlier studies. Atrial fibrillation is not always symptomatic. However, it increases the risk of embolic stroke, systemic embolism, and cardiovascular events and mortality by a few folds. Current guidelines recommend atrial fibrillation screen in high-risk people by pulse palpitation, handheld electrocardiography, oscillometric blood pressure measurement, and so on. Current technology with a smartphone camera-based photoplethysmography even supports for atrial fibrillation screen in massive populations. Cardioversion in some patients with atrial fibrillation is possible. However, even the advanced invasive techniques only ameliorate symptoms but do not improve clinical outcomes. Anticoagulation prevents embolic stroke and systemic embolism. The cost is huge, and bleeding happens in some patients, which limits the use of this efficacious therapeutic modality. Prevention of atrial fibrillation is essential. Among several others, hypertension is a proven risk factor of atrial fibrillation. A recent large study in close to 10 million Koreans provided strong evidence on the association between the duration and degree of hypertension and atrial fibrillation. There is some observational evidence that blood pressure reduction may be beneficial in the prevention of atrial fibrillation. There is not much but some evidence from post hoc analyses of randomized controlled trials that investigated effect of antihypertensive treatment on the incidence of atrial fibrillation in patients with hypertension. In the SHEP (Systolic Hypertension in the Elderly Program) trial, active antihypertensive treatment (targeting systolic blood pressure <150 mm Hg), compared with placebo, tended to reduce the incidence rate of atrial fibrillation in elderly patients with isolated systolic hypertension (systolic blood pressure ≥160 mm Hg and diastolic blood pressure <90 mm Hg) during a mean of 4.5 years follow-up (1.82% versus 2.32%). The between-group difference, however, did not attain statistical significance (hazard ratio, 0.78 [95% CI, 0.52–1.17]; P=0.20). In the ACCORD-BP (Action to Control Cardiovascular Risk in Diabetes) trial, intensive antihypertensive treatment (targeting systolic blood pressure <120 mm Hg), compared with standard therapy (targeting systolic blood pressure <140 mm Hg), also tended to reduce the incidence of atrial fibrillation in patients with hypertension and diabetes mellitus during a mean of 4.4 years follow-up (37 versus 45 incident cases; hazard ratio, 0.85 [95% CI, 0.55–1.32]; P=0.48). If these 2 trials were combined, the difference was still not statistically significant (P=0.13). In this issue of the journal, 2 post hoc analyses of the SPRINT (Systolic Blood Pressure Intervention Trial) provided important evidence on the benefit of intensive antihypertensive treatment in the prevention of incident atrial fibrillation. One analysis was performed by the SPRINT investigators at the SPRINT electrocardiogram reading center with full access to the raw data and electrocardiogram recordings (Table). The other was from the publicly available dataset for the SPRINT trial. Probably because of the difference in data and electrocardiogram access, the 2 analyses were different in the selection of study participants and hence also the number of incident cases of atrial fibrillation. A major difference was that the analysis from Soliman et al excluded patients with an electrocardiogram atrial fibrillation at baseline (n=127) and those with missing electrocardiogram at baseline (n=138) or during follow-up (n=1074), whereas the analysis from Parcha et al excluded the so-called preexisting atrial fibrillation according to electrocardiogram at baseline and history of atrial fibrillation (n=778). Thus, those patients with a history of atrial fibrillation but an electrocardiogram sinus rhythm at baseline were eventually included in the analysis from Soliman et al but not the one from Parcha et al. In this group of patients with paroxysmal atrial fibrillation at baseline, the recurrence rate during follow-up could be high. That may explain to some extent why the incidence rate of atrial fibrillation was much higher in the former (6.21 and 8.33 per 1000 person-years in the intensive and standard therapy groups, respectively) than This manuscript was sent to Dr Oparil, Consulting Editor, for review by expert referees, editorial decision, and final disposition. From the Centre of Epidemiological Studies and Clinical Trials, The Shanghai Institute of Hypertension, Department of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, China. Correspondence to Ji-Guang Wang, MD, PhD, The Shanghai Institute of Hypertension, Ruijin 2nd Rd 197, Shanghai 200025, China. Email jiguangwang@rjh.com. cn Prevention of Atrial Fibrillation by Intensive Antihypertensive Treatment