Metabolic Syndrome and Incidence of AF Among Blacks and Whites
Metabolic Syndrome and Incidence of AF Among Blacks and Whites
Background The metabolic syndrome (MetSyn) has been implicated in the development of atrial fibrillation (AF); however, knowledge of this association among blacks is limited.
Methods We determined the risk of incident AF through December 2005 in relation to baseline (1987–1989) MetSyn status in 15,094 participants of the Atherosclerosis Risk in Communities study.
Results Over a mean follow-up of 15.4 years, 1,238 incident AF events were identified. The hazard ratio (HR) for AF among individuals with, compared to those without, the MetSyn was 1.67 (95% CI 1.49–1.87), and associations did not differ by race (P for interaction = .73). The population attributable risk of AF from the MetSyn was 22%. The multivariable-adjusted HRs (95% CI) for each MetSyn component were 1.95 (1.72–2.21) (elevated blood pressure), 1.40 (1.23–1.59) (elevated waist circumference), 1.20 (1.06–1.37) (low high-density lipoprotein cholesterol), 1.16 (1.03–1.31) (impaired fasting glucose), and 0.95 (0.84–1.09) (elevated triglycerides). A monotonically increasing risk of AF with increasing number of MetSyn components was observed, with an HR of 4.40 (95% CI 3.25–5.94) for those with all 5 MetSyn components compared to those with 0 components.
Conclusion In this large cohort, the MetSyn and most of its components were associated with a higher risk of AF in both blacks and whites. Given the high prevalence of the MetSyn, strategies to prevent its development or to control individual components may reduce the burden of AF.
The metabolic syndrome (MetSyn) is defined as a clustering of ≥3 of the following atherosclerotic risk factors: abdominal obesity, elevated triglycerides (TG), low high-density lipoprotein cholesterol (HDL-c), elevated blood pressure, and impaired glucose tolerance. Although the significance of the MetSyn as a well-defined clinical entity is uncertain, previous research has implicated this disorder and some of its individual components in the development of atrial fibrillation (AF).
The mechanisms relating the MetSyn to increased risk of developing AF are not fully understood. The MetSyn affects atrial anatomy by increasing atrial size, possibly increasing AF risk as a consequence. Alternatively, the MetSyn may predispose to the development of coronary heart disease (CHD) or heart failure (HF), in turn increasing the risk of AF.
Knowledge on the association of the MetSyn with AF risk among blacks is limited. Previous studies have suggested that AF is less common in blacks than whites. However, it is well-known that blacks have a higher prevalence of the MetSyn and most of its components than do whites. Therefore, our study aimed to determine the association of the MetSyn and its individual components with the risk of incident AF in a population-based cohort of blacks and whites.
Abstract and Introduction
Abstract
Background The metabolic syndrome (MetSyn) has been implicated in the development of atrial fibrillation (AF); however, knowledge of this association among blacks is limited.
Methods We determined the risk of incident AF through December 2005 in relation to baseline (1987–1989) MetSyn status in 15,094 participants of the Atherosclerosis Risk in Communities study.
Results Over a mean follow-up of 15.4 years, 1,238 incident AF events were identified. The hazard ratio (HR) for AF among individuals with, compared to those without, the MetSyn was 1.67 (95% CI 1.49–1.87), and associations did not differ by race (P for interaction = .73). The population attributable risk of AF from the MetSyn was 22%. The multivariable-adjusted HRs (95% CI) for each MetSyn component were 1.95 (1.72–2.21) (elevated blood pressure), 1.40 (1.23–1.59) (elevated waist circumference), 1.20 (1.06–1.37) (low high-density lipoprotein cholesterol), 1.16 (1.03–1.31) (impaired fasting glucose), and 0.95 (0.84–1.09) (elevated triglycerides). A monotonically increasing risk of AF with increasing number of MetSyn components was observed, with an HR of 4.40 (95% CI 3.25–5.94) for those with all 5 MetSyn components compared to those with 0 components.
Conclusion In this large cohort, the MetSyn and most of its components were associated with a higher risk of AF in both blacks and whites. Given the high prevalence of the MetSyn, strategies to prevent its development or to control individual components may reduce the burden of AF.
Introduction
The metabolic syndrome (MetSyn) is defined as a clustering of ≥3 of the following atherosclerotic risk factors: abdominal obesity, elevated triglycerides (TG), low high-density lipoprotein cholesterol (HDL-c), elevated blood pressure, and impaired glucose tolerance. Although the significance of the MetSyn as a well-defined clinical entity is uncertain, previous research has implicated this disorder and some of its individual components in the development of atrial fibrillation (AF).
The mechanisms relating the MetSyn to increased risk of developing AF are not fully understood. The MetSyn affects atrial anatomy by increasing atrial size, possibly increasing AF risk as a consequence. Alternatively, the MetSyn may predispose to the development of coronary heart disease (CHD) or heart failure (HF), in turn increasing the risk of AF.
Knowledge on the association of the MetSyn with AF risk among blacks is limited. Previous studies have suggested that AF is less common in blacks than whites. However, it is well-known that blacks have a higher prevalence of the MetSyn and most of its components than do whites. Therefore, our study aimed to determine the association of the MetSyn and its individual components with the risk of incident AF in a population-based cohort of blacks and whites.