A randomized placebo-controlled trial of massage therapy on the immune system of preterm infants.

OBJECTIVES The aim of this study was to investigate the effects of massage therapy (MT) on the immune system of preterm infants. The primary hypothesis was that MT compared with sham therapy (control) will enhance the immune system of stable premature infants by increasing the proportion of their natural killer (NK) cell numbers. METHODS A randomized placebo-controlled trial of MT versus sham therapy (control) was conducted among stable premature infants in the NICU. Study intervention was provided 5 days per week until hospital discharge for a maximum of 4 weeks. Immunologic evaluations (absolute NK cells, T and B cells, T cell subsets, and NK cytotoxicity), weight, number of infections, and length of hospital stay were also evaluated. RESULTS The study enrolled 120 infants (58 massage; 62 control). At the end of the study, absolute NK cells were not different between the 2 groups; however, NK cytotoxicity was higher in the massage group, particularly among those who received ≥5 consecutive days of study intervention compared with control (13.79 vs 10 lytic units, respectively; P = .04). Infants in the massage group were heavier at end of study and had greater daily weight gain compared with those in the control group; other immunologic parameters, number of infections, and length of stay were not different between the 2 groups. CONCLUSIONS In this study, MT administered to stable preterm infants was associated with higher NK cytotoxicity and more daily weight gain. MT may improve the overall outcome of these infants. Larger studies are needed.