Potential underlying mechanisms for greater weight gain in massaged preterm infants

Abstract

In this paper, potential underlying mechanisms for massage therapy effects on preterm infant weight gain are reviewed. Path analyses are presented suggesting that: (1) increased vagal activity was associated with (2) increased gastric motility, which, in turn, was related to (3) greater weight gain; and (4) increased IGF-1 was related to greater weight gain. The change in vagal activity during the massage explained 49% of the variance in the change in gastric activity. And, the change in vagal activity during the massage explained 62% of the variance in the change in insulin. That the change in gastric activity was not related to the change in insulin suggests two parallel pathways via which massage therapy leads to increased weight gain: (1) insulin release via the celiac branch of the vagus; and (2) increased gastric activity via the gastric branch of the vagus.

Copyright © 2010 Elsevier Inc. All rights reserved.

Figures

Figure 1

Mean sympathetic and parasympathetic activity 15 minutes before, during, and after treatment (error bars denote ± 2 standard errors). Group-by-time interaction statistics for each measurement are presented under each line plot.

Figure 2

Mean gastric activity 15 minutes before, during, and after treatment (error bars denote ± 2 standard errors). Group-by-time interaction statistics for each measurement are presented under each line plot.

Figure 3

Mean vagal activity and gastric motility on the first and last days of the study for preterm infants assigned to the control (closed circles) and massage group (open circles).

Figure 4

Hypothesized path analyses models for mediating variables contributing to weight gain in massage and control groups.

Figure 5

Corrected path analyses models for mediating variables contributing to weight gain in massage and control groups

Figure 6

Path analysis conducted for the massage (N=14) group for infants with Insulin data