Sex-specific relationship between abdominal obesity and new-onset atrial fibrillation in the general Japanese population

Association between body mass index and long-term clinical outcomes in patients with non-valvular atrial fibrillation taking oral anticoagulants

BACKGROUND AND AIMS

The association between body mass index (BMI) and clinical outcomes of patients with non-valvular atrial fibrillation (NVAF) taking oral anticoagulants (OACs) are controversial, and we thus analyzed the large registry data to elucidate them.

METHODS AND RESULTS

We conducted a historical cohort study at 71 centers in Japan and included outpatients with NVAF taking vitamin K antagonists (VKAs). Physicians in charge could change VKAs to direct OACs based on their judgement during follow-up period. We categorized patients into four BMI groups (kg/m²): underweight (BMI < 18.5), normal weight (18.5 ≤ BMI < 25), overweight (25 ≤ BMI < 30), and obese (30 ≤ BMI). The effects of each BMI group relative to the normal weight group on clinical outcomes consisting of all-cause death, ischemic events, and bleeding events were estimated using Cox proportional hazard models adjusting for potential confounders. We also constructed restricted cubic spline regression model adjusted by multivariable Cox proportional hazard models. We included 6927 patients consisting of an underweight (n = 386), normal weight (n = 3785), overweight (n = 2174), and obese (n = 582) groups. The median follow-up period was 3.9 years. In the underweight group, the adjusted hazard ratios (HRs) for all-cause death and ischemic events were 1.75 (1.30-2.34) and 1.61 (1.04-2.50). The HR for all-cause death was 0.63 (0.49-0.82) in the overweight group. Restricted cubic spline regression models confirmed that lower BMI showed significantly higher risks for all-cause death and ischemic events.

CONCLUSION

Among NVAF patients taking OACs, underweight patients had higher risks of all-cause death and ischemic events than other patients. Overweight patients had lower risk of all-cause death.

Blood pressure, hypertension and the risk of atrial fibrillation: a systematic review and meta-analysis of cohort studies

Elevated blood pressure and hypertension have been associated with increased risk of atrial fibrillation in a number of epidemiological studies, however, the strength of the association has differed between studies. We conducted a systematic review and meta-analysis of the association between blood pressure and hypertension and atrial fibrillation. PubMed and Embase databases were searched for studies of hypertension and blood pressure and atrial fibrillation up to June 6th 2022. Cohort studies reporting adjusted relative risk (RR) estimates and 95% confidence intervals (CIs) of atrial fibrillation associated with hypertension or blood pressure were included. A random effects model was used to estimate summary RRs. Sixty eight cohort studies were included in the meta-analysis. The summary RR was 1.50 (95% CI: 1.42-1.58, I2 = 98.1%, n = 56 studies) for people with hypertension compared to those without hypertension (1,080,611 cases, 30,539,230 participants), 1.18 (95% CI: 1.16-1.21, I2 = 65.9%, n = 37 studies) per 20 mmHg increase in systolic blood pressure (346,471 cases, 14,569,396 participants), and 1.07 (95% CI: 1.03-1.11, I2 = 91.5%, n = 22 studies) per 10 mmHg increase in diastolic blood pressure (332,867 cases, 14,354,980 participants). There was evidence of a nonlinear association between diastolic blood pressure and atrial fibrillation with a steeper increase in risk at lower levels of diastolic blood pressure, but for systolic blood pressure the association appeared to be linear. For both systolic and diastolic blood pressure, the risk increased even within the normal range of blood pressure and persons at the high end of systolic and diastolic blood pressure around 180/110 mmHg had a 1.8-2.3 fold higher risk of atrial fibrillation compared to those with a blood pressure of 90/60 mmHg. These results suggest that elevated blood pressure and hypertension increases the risk of atrial fibrillation and there is some increase in risk even within the normal range of systolic and diastolic blood pressure.

Further Advances in Atrial Fibrillation Research: A Metabolomic Perspective

Atrial fibrillation involves an important type of heart arrhythmia caused by a lack of control in the electrical signals that arrive in the heart, produce an irregular auricular contraction, and induce blood clotting, which finally can lead to stroke. Atrial fibrillation presents some specific characteristics, but it has been treated and prevented using conventional methods similar to those applied to other cardiovascular diseases. However, due to the influence of this pathology on the mortality caused by cerebrovascular accidents, further studies on the molecular mechanism of atrial fibrillation are required. Our aim here is provide a compressive review of the use of metabolomics on this condition, from the study of the metabolic profile of plasma to the development of animal models. In summary, most of the reported studies highlighted alterations in the energetic pathways related to the development of the condition.