Am J Cardiovasc Dis 2013;3(4):239-246

Original Article
Heart rate variability and metabolic rate in healthy young adults with low
birth weight

Gunther Weitz, Hendrik Bonnemeier, Sven Süfke, Peter Wellhöner, Hendrik Lehnert, Christoph Dodt

Medical Department I, University Clinic of Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck,
Germany; Medical Department III, University Clinic of Schleswig-Holstein, Campus Kiel, Arnold-Heller-Straße 3, 24105 Kiel,
Germany; Präklinik - Interdisziplinäres Notfallzentrum, Städtisches Klinikum München Bogenhausen,
Englschalkingerstrasse 77, 81925 München, Germany

Received September 20, 2013; Accepted October 25, 2013; Epub November 1, 2013; Published November 15, 2013

Abstract: Objective: Low birth weight (LBW) is associated with obesity and a higher cardiovascular risk in adult life. Since
autonomic dysfunction could be a pathophysiological factor for this association, we assessed the impact of LBW on
cardiac autonomic activity and metabolic rate in young adulthood. We hypothesized that the autonomic tone could be
coupled with the metabolic rate in subjects with LBW. Methods: Heart rate variability (HRV) from 24-hour
Holter-electrocardiograms was measured in 15 healthy adults aged 20 to 30 years with LBW (<2500g at term) and 15
paired subjects with normal birth weight (NBW). The pairs were closely matched by gender, age, and body mass index.
Resting energy expenditure was measured by indirect calorimetry and body composition by bioimpedance. Results: Global
HRV parameters were significantly higher in the LBW group and a marked difference was observed in the long wave
fluctuations of the frequency domain (very low frequency). These fluctuations were positively correlated with the resting
energy expenditure per body weight in the LBW and negatively in the NBW group. Only in the LBW group HRV was closely
related to body fat. Interpretation: This case-control study indicates that autonomous nervous function is not generally
deteriorated in young adults with LBW and has a significant association with metabolic rate. Thus, it may be a determinant
of the body weight regulation in this group. The higher cardiovascular risk in ageing individuals with LBW would therefore
rather be a consequence of weight gain than of a primary autonomous nervous dysfunction. (AJCD1309005).

Keywords: Low birth weight, autonomic nervous system, metabolic rate, weight gain

Address correspondence to: Dr. Gunther Weitz, Medical Department I, University Clinic of Schleswig-Holstein, Campus
Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany. Tel: ++49 4515006033; Fax: ++49 4515006242; E-mail:
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