The aging process of the heart: obesity is the main risk factor for left atrial enlargement during aging the MONICA/KORA (monitoring of trends and determinations in cardiovascular disease/cooperative research in the region of Augsburg) study.
OBJECTIVE
This prospective study evaluated the association of obesity and hypertension with left atrial (LA) volume over 10 years.


BACKGROUND
Although left atrial enlargement (LAE) is an independent risk factor for atrial fibrillation, stroke, and death, little information is available about determinants of LA size in the general population.


METHODS
Participants (1,212 men and women, age 25 to 74 years) originated from a sex- and age-stratified random sample of German residents of the Augsburg area (MONICA S3). Left atrial volume was determined by standardized echocardiography at baseline and again after 10 years. Left atrial volume was indexed to body height (iLA). Left atrial enlargement was defined as iLA > or =35.7 and > or =33.7 ml/m in men and women, respectively.


RESULTS
At baseline, the prevalence of LAE was 9.8%. Both obesity and hypertension were independent predictors of LAE, obesity (odds ratio [OR]: 2.4; p < 0.001) being numerically stronger than hypertension (OR: 2.2; p < 0.001). Adjusted mean values for iLA were significantly lower in normal-weight hypertensive patients (25.4 ml/m) than in obese normotensive individuals (27.3 ml/m; p = 0.016). The highest iLA was found in the obese hypertensive subgroup (30.0 ml/m; p < 0.001 vs. all other groups). This group also presented with the highest increase in iLA (+6.0 ml/m) and the highest incidence (31.6%) of LAE upon follow-up.


CONCLUSIONS
In the general population, obesity appears to be the most important risk factor for LAE. Given the increasing prevalence of obesity, early interventions, especially in young obese individuals, are essential to prevent premature onset of cardiac remodeling at the atrial level.
Stritzke
Jan
J
Department of Internal Medicine II, University of Lübeck, Lübeck, Germany.
Markus
Marcello Ricardo Paulista
MR
Duderstadt
Stefanie
S
Lieb
Wolfgang
W
Luchner
Andreas
A
Döring
Angela
A
Keil
Ulrich
U
Hense
Hans-Werner
HW
Schunkert
Heribert
H
D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology*; D016279:Atrial Function, Left / Q000502:physiology*; D006332:Cardiomegaly / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology*; D018450:Disease Progression; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D005858:Germany / Q000453:epidemiology; D006325:Heart Atria / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D009765:Obesity / Q000150:complications* / Q000453:epidemiology; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors