Compliance of nursing home residents with a nutrient- and energy-dense oral nutritional supplement determines effects on nutritional status

OBJECTIVES: Administration of oral nutritional supplements (ONS) is an effective strategy to treat and avoid malnutrition, a persisting issue in nursing homes. However, little is known about compliance in the NH population. This study aimed to analyse the effects of compliance of NH residents with a low-volume, nutrient- and energy-dense ONS on nutritional status and to identify residents' characteristics associated with compliance. DESIGN AND SETTING: Randomized, controlled trial in nursing homes. PARTICIPANTS AND INTERVENTION: 87 nursing home residents (87 ± 6y, 91% female) with malnutrition or at risk of malnutrition were randomly allocated to an intervention group (IG) receiving 2 x 125 ml ONS (2.4 kcal/ml)/d for 12 weeks, or the control group (CG) with usual care. MEASUREMENTS: ONS intake was recorded daily and compliance calculated. Low and high compliance were defined as ≤ 30% and ≥ 80% of provided ONS actually consumed, respectively. Body weight (BW), BMI, upper-arm (UAC) and calf-circumference (CC) and MNA-SF were assessed at baseline and after 12 weeks. Associations between compliance and changes of nutritional parameters and residents' characteristics were analysed. RESULTS: Compliance was high in 35.7% and low in 28.6% of the IG (n=42). BW change was significantly higher in subjects with high compliance (median +3.0 (interquartile range +2.1;+3.8) kg, n=15) than in those with low compliance (-0.2 (-2.2;+1.6) kg, n=12) and CG (-0.1 (-1.2; +0.6) kg, n=35; p<0.001), and significantly correlated with compliance in IG (r=0.691; p<0.001). Significant differences and correlations were also identified for BMI, UAC and MNA-SF. High compliance was more often observed in residents with malnutrition (66.7 vs. 27.3%) and chewing difficulties (77.8 vs. 24.2%) than in those without these conditions. Low compliance was more prevalent in residents who were immobile (45.0 vs. 13.6%), depressed (33.3 vs. 6.7%) or had gastrointestinal complaints (50.0 vs. 17.9%) (all p<0.05). CONCLUSIONS: A high compliance of nursing home residents with a low volume, nutrient- and energy dense ONS was related to a significantly improved nutritional status in comparison to low compliance and therefore enhanced the effectiveness of ONS. A higher compliance may be achieved by consideration of different residents' characteristics.