Enhanced weight gain in preterm infants receiving lactase-treated feeds: a randomized, double-blind, controlled trial.
To evaluate whether lactase-treated preterm feeds enhance weight gain and feeding tolerance in premature infants.
                Prospective, double-blind, randomized, controlled trial involving 130 infants (26-34 weeks postconceptual age). The primary outcome variable was weight gain (g per day). Other outcome measures included gains in length and head circumference, biochemical indexes of nutritional status, feeding intolerance, and incidence of necrotizing enterocolitis.
                On study day 10, weight gain (mean +/- SEM) of the treatment group was significantly greater (P <.05) than that of the control group (20.4 +/- 1.8 g/day vs 15.5 +/- 1.6 g/day). By study end, no significant difference in weight gain between treatment and control groups was observed. The difference in serum albumin level was significant at study day 14, with a value of 29.3 +/- 0.6 g/L in the treatment group compared with 27.1 +/- 0.4 g/L in the control group (P <.01). There were no significant differences in caloric intakes, length gain, head circumference gain, feeding intolerance, and incidence of necrotizing enterocolitis.
                Weight gain may be enhanced during the period of low functional lactase activity of prematurity by addition of lactase to preterm feeds. No adverse effects on feeding tolerance resulted from this treatment.
The only randomized trial to date provides no evidence of significant benefit to preterm infants from adding lactase to their feeds. Further research regarding effectiveness and safety are required before practice recommendations can be made. Randomized controlled trials comparing lactase versus placebo treated feeds and enrolling infants when enteral feeds are introduced are required. The primary and secondary outcomes for effectiveness and safety should include those identified in this review.