Understanding the interplay between factors that influence bone mineral density in CF.

BACKGROUND AND OBJECTIVES: Multiple factors affect bone mineral density (BMD) in cystic fibrosis (CF). Our aim was to perform comprehensive analyses of parameters potentially contributing to BMD. METHODS: A prospective single-center study assessing BMD, and correlations with multiple parameters including pancreatic status, lung functions, 6-minute walk test (6MWT), clinical score (modified Shwachman-Kulczycki [SK] score), vitamin D, nutritional intake, hand grip strength (HGS), habitual physical activity (smart watches), and quality of life (SF-36 questionnaire). RESULTS: Forty CF patients, mean age 18.3 ± 8.1 years, forced expiratory volume in 1 second 74.7% ± 17.9% predicted. Fifteen (37.5%) and 11 (27.5%) had osteopenia and osteoporosis, respectively. BMD was similar in pancreatic sufficient (pancreatic sufficient [PS], n = 15) and insufficient (pancreatic insufficient [PI], n = 25); median hip z score -1.5 ((-2.7)-(+0.2)) vs -1.5 ((-3.5)-(+0.7)), P = .79; spine -0.8 ((-2.2)-(+2)) vs -1.2 ((-4.4)-(+1.5)), P = .39 in PS vs PI, respectively. BMD correlated with HGS (r = .72, P < .001 hip; r = .52, P = .001 spine) and fat-free mass index (r = .81, P < .001 hip; r = .63, P < .001 spine). BMD z score correlated weakly with SK score and moderately with SF-36 general health. Data from smart watches, nutrition questionnaires, and 6MWT did not correlate with BMD. In a multivariate model, age and SK score predicted spine z score BMD. CONCLUSIONS: A substantial number of CF patients have low BMD. Similar rates in PS and PI suggest that other factors, such as disease severity, may contribute to low BMD. SK and age, which can easily be obtained even with limited resources, were the best predictors of low BMD. Further larger multicenter studies are warranted to evaluate the contribution of multifactorial etiologies to low BMD in CF.

Standardized versus individualized parenteral nutrition in very low birth weight infants: a comparative study.

BACKGROUND: Parenteral nutrition (PN) improves the growth and outcome of very low birth weight (VLBW) infants. Optimal PN composition, standard (STD-PN) or individualized (IND-PN), is still controversial. AIM: To compare IND-PN and STD-PN as to nutritional and growth parameters, complications and cost. PATIENTS AND METHODS: 140 VLBW infants were studied. Each of the 70 neonates from the IND-PN group was matched with a neonate of similar gestational age (GA; +/-4 days) on STD-PN. Data collection included demographic, maternal, intrapartum, neonatal, interventional, growth and nutritional data. RESULTS: Compared to STD-PN infants, IND-PN infants had a significantly lower mean birth weight, greater need for resuscitation at birth and interventions thereafter. Nevertheless, IND-PN infants showed significantly greater weight gain SDS during the 1st week (p = 0.036) and the 1st month of life (p = 0.0004), and higher discharge weight SDS (p = 0.012) and head circumference SDS (p = 0.006). IND-PN infants received higher mean daily caloric intakes. They also had significantly shorter durations of exclusive PN and needed less electrolyte corrections. CONCLUSIONS: Compared to STD-PN infants, IND-PN infants achieved significantly better growth without added clinical or laboratory complications, had a shorter period of exclusive PN and less electrolyte corrections. IND-PN, in accordance with the current more aggressive nutritional approach, appears optimal for PN of VLBW infants. Yet, STD-PN with adequate composition is an appropriate alternative.