Nutritional perspectives of children with Crohn's disease: a single-centre cohort observation of disease activity, energy expenditure and dietary intake.

BACKGROUND/OBJECTIVES: Children with Crohn's disease often demonstrate nutritional recovery during primary therapy at diagnosis, but long-term nutritional support is sometimes necessary. Evidence to inform best nutritional practice including energy and micronutrient requirements is limited. The principal objective of this study was to determine how energy expenditure and physical activity vary with disease activity over the first year following diagnosis.

SUBJECTS/METHODS: Twenty children were studied at diagnosis with Crohn's disease and were followed up over 1 year while receiving treatment according to national guidelines. The majority of children (13) were treated with exclusive enteral nutrition. At study visits, height, weight, bioelectrical impedance, resting energy expenditure by indirect calorimetry, tri-axial accelerometer and blood investigations were performed alongside clinical assessment.

RESULTS

There was no significant effect of disease activity on resting energy expenditure (REE). Physical activity was greater after primary therapy (Z=3.31, P<0.01). Median wPCDAI fell from 58 at diagnosis to 7.5 after primary therapy and was 7.5 at 1 year. Weight s.d.s increased from -1.67 to -0.86 and lean index s.d.s increased from -2.93 to -1.64, although the increase was mostly in the first 2 months. Median height s.d.s was unchanged throughout this study. There was a significant association between dietary intake and weight gain (r=0.8 P<0.01) but not height gain. Persistent micronutrient deficits beyond diagnosis were seen for both iron and vitamin D.

CONCLUSIONS

This study has demonstrated that REE does not change significantly through different phases of disease activity, but physical activity is low at diagnosis. Children with Crohn's disease should be screened for deficiencies of iron and vitamin D.