Effects of oral nutritional supplements in normally nourished or mildly undernourished geriatric patients after surgery for hip fracture: a randomized clinical trial

Abstract

Background: Oral nutritional supplements have been recommended after orthopedic surgery in geriatric patients to reduce postoperative complications. However, tolerability of supplements could be a limitation, and their universal use is not supported by the heterogeneity of previous studies, especially in patients without malnutrition.

Methods: This study is a randomized, controlled, open, parallel, 3-arm clinical trial comparing supplementation with protein powder dissolved in liquids to aim at 36 g of protein per day, energy and protein supplements to aim at 37.6 g of protein and 500 kcal per day, or no intervention in normally nourished or mildly undernourished patients. Outcomes were serum albumin, prealbumin, retinol-binding globulin, and body mass index, among others. Postoperative complications were also recorded.

Results: Ninety patients aged 83.8 +/- 6.6 years were included. The mean ingested amount of supplements was 41.1% +/- 20.6% in the protein powder supplement group and 51.4% +/- 13.2% in the energy protein supplement group (t = 2.278, P = .027). Postoperative supplements had no effect on the nutrition status during in-hospital follow-up, as assessed by serum albumin (P = .251), prealbumin (P = .530), retinol-binding globulin (P = .552), or body mass index (P = .582). Multivariate analysis showed that length of hospital stay with an established complication until its resolution (beta = .230, P = .031), total hospital stay (beta = .450, P < .001), baseline body mass index (beta = .204, P = .045), and total daily ingested proteins per body weight (beta = .252, P = .018) were predictive variables on the change in serum albumin (R2 = 0.409, F = 11.246, P < .001).

Conclusions: Oral nutritional supplements in normally nourished or only mildly undernourished geriatric patients with hip fracture submitted to surgery may be of interest for patients with postoperative complications and long hospital stays.