Long-Term Skeletal Disproportion in Childhood-Onset Crohn's Disease

Clinical Variables Associated With Statural Growth in Pediatric Crohn's Disease Differ by Sex (The Growth Study)

BACKGROUND

Statural growth impairment is more common in male patients with Crohn's disease (CD). We identified clinical variables associated with height z score differences by sex in children participating in the Growth Study, a prospective multicenter longitudinal study examining sex differences in growth impairment in pediatric CD.

METHODS

Patients with CD (female patients with bone age [BA] ≥4 years 2 months and ≤12 years; male patients with BA ≥5 years and ≤14 years at screening) who had completed study visit 1 qualified. The height z score difference was computed as height z score based on chronological age minus height z score based on BA.

RESULTS

One hundred thirteen patients with CD (36% female) qualified. The mean chronological age was 12.0 ± 1.8 (SD) years. The magnitude of the mean height z score difference was significantly greater in female patients (-0.9 ± 0.8) than in male patients (-0.5 ± 0.9; P = 0.021). An initial classification of inflammatory bowel disease as CD (P = 0.038) and perianal disease behavior at diagnosis (P = 0.009) were associated with higher standardized height gain with BA progression, and arthralgia at symptom onset (P = 0.016), azathioprine/6-merpcaptopurine (P = 0.041), and probiotics (P ≤ 0.021) were associated with lower standardized height gain with BA progression in female patients. Patient-reported poor growth at symptom onset (P = 0.001), infliximab (P ≤ 0.025), biologics (P ≤ 0.015), methotrexate (P = 0.042), and vitamin D (P ≤ 0.010) were associated with higher standardized height gain with BA progression, and initial classification as CD (P = 0.025) and anorexia (P = 0.005) or mouth sores (P = 0.004) at symptom onset were associated with lower standardized height gain with BA progression in male patients.

CONCLUSIONS

Different clinical variables were associated with statural growth in male patients vs female patients, suggesting that sex-specific molecular pathways lead to statural growth impairment in CD.

Continued Statural Growth in Older Adolescents and Young Adults With Crohn's Disease and Ulcerative Colitis Beyond the Time of Expected Growth Plate Closure

BACKGROUND

Cessation of statural growth occurs with radiographic closure of the growth plates, radiographically defined as bone age (BA) 15 years in females and 17 in males.

METHODS

We determined the frequency of continued growth and compared the total height gain beyond the time of expected growth plate closure and the chronological age at achievement of final adult height in Crohn's disease (CD) vs ulcerative colitis (UC) and described height velocity curves in inflammatory bowel disease (IBD) compared with children in the National Health and Nutrition Examination Survey (NHANES). We identified all females older than chronological age (CA) 15 years and males older than CA 17 years with CD or UC in the ImproveCareNow registry who had height documented at ≥3 visits ≥6 months apart.

RESULTS

Three thousand seven patients (48% female; 76% CD) qualified. Of these patients, 80% manifested continued growth, more commonly in CD (81%) than UC (75%; P = 0.0002) and in females with CD (83%) than males with CD (79%; P = 0.012). Median height gain was greater in males with CD (1.6 cm) than in males with UC (1.3 cm; P = 0.0004), and in females with CD (1.8 cm) than in females with UC (1.5 cm; P = 0.025). Height velocity curves were shifted to the right in patients with IBD vs NHANES.

CONCLUSIONS

Pediatric patients with IBD frequently continue to grow beyond the time of expected growth plate closure. Unexpectedly, a high proportion of patients with UC exhibited continued growth, indicating delayed BA is also common in UC. Growth, a dynamic marker of disease status, requires continued monitoring even after patients transition from pediatric to adult care.

Introduction to and Screening Visit Results of the Multicenter Pediatric Crohn's Disease Growth Study

BACKGROUND

Statural growth impairment is more common in males with Crohn's disease (CD). We assessed sex differences in height Z score differences and bone age (BA) Z scores and characterized age of menarche in a novel contemporary cohort of pediatric CD patients undergoing screening for enrollment in the multicenter longitudinal Growth Study.

METHODS

Crohn's disease patients (females with chronological age [CA] 5 years and older and younger than 14 years; males with CA 6 years and older and younger than 16 years) participated in a screening visit for the Growth Study. Height BA-Z scores are height Z scores calculated based on BA. Height CA-Z scores are height Z scores calculated based on CA. The height Z score difference equals height CA-Z score minus height BA-Z score.

RESULTS

One hundred seventy-one patients (60% male) qualified for this analysis. Mean CA was 12.2 years. Mean height CA-Z score was -0.4, and mean height BA-Z score was 0.4 in females. Mean height CA-Z score was -0.1, and mean height BA-Z score was 0.2 in males. The absolute value of the mean height Z score difference was significantly greater in females (0.8) than males (0.3; P = 0.005). The mean BA-Z score in females (-1.0) was significantly lower than in males (-0.2; P = 0.002). The median CA at menarche was 13.6 (95% CI, 12.6-14.6) years.

CONCLUSIONS

Our screening visit data suggest that standardized height gain is lower in males with skeletal maturation and delayed puberty is common in females in CD. We are investigating these findings in the ongoing Growth Study.

Skeletal disproportion in glucocorticoid-treated boys with Duchenne muscular dystrophy

We aimed to compare body segment and bone lengths in glucocorticoid-treated boys with Duchenne muscular dystrophy (DMD) with healthy controls using dual-energy absorptiometry (DXA) images. Total height (Ht), sitting height (SH), leg length (LL) and bone lengths (femur, tibia) in boys with DMD and age-matched control boys were measured using DXA. Thirty boys with DMD (median age 10.0 years (6.1, 16.8)) were compared with 30 controls. SH in DMD was 3.3 cm lower (95% CI - 6.1, - 0.66; p = 0.016). LL in DMD was 7.3 cm lower (95% CI - 11.2, - 3.4; p < 0.0001). SH:LL of boys with DMD was higher by 0.08 (95% CI 0.04, 0.12; p < 0.0001). Femur length in DMD was 2.4 cm lower (95% CI - 4.6, - 0.12; p = 0.04), whereas tibial length in DMD was 4.8 cm lower (95% CI - 6.7, - 2.9; p < 0.0001). SH:LL was not associated with duration of glucocorticoid use (SH:LL β = 0.003, 95% CI - 0.01 to 0.002, p = 0.72).Conclusion: Glucocorticoid-treated boys with DMD exhibit skeletal disproportion with relatively shorter leg length and more marked reduction of distal long bones. As glucocorticoid excess is not associated with such disproportion, our findings raise the possibility of an intrinsic disorder of growth in DMD. What is Known • Severe growth impairment and short stature are commonly observed in boys with Duchenne muscular dystrophy (DMD), especially those treated with long-term glucocorticoids (GC). • In other groups of children with chronic conditions and/or disorders of puberty, skeletal disproportion with lower spinal length has been reported. What is New • Growth impairment in GC-treated boys with DMD was associated with skeletal disproportion in relation to age, with lower limbs and distal long bones affected to a greater degree.

An automated identification and analysis of ontological terms in gastrointestinal diseases and nutrition-related literature provides useful insights

With an unprecedented growth in the biomedical literature, keeping up to date with the new developments presents an immense challenge. Publications are often studied in isolation of the established literature, with interpretation being subjective and often introducing human bias. With ontology-driven annotation of biomedical data gaining popularity in recent years and online databases offering metatags with rich textual information, it is now possible to automatically text-mine ontological terms and complement the laborious task of manual management, interpretation, and analysis of the accumulated literature with downstream statistical analysis. In this paper, we have formulated an automated workflow through which we have identified ontological information, including nutrition-related terms in PubMed abstracts (from 1991 to 2016) for two main types of Inflammatory Bowel Diseases: Crohn’s Disease and Ulcerative Colitis; and two other gastrointestinal (GI) diseases, namely, Coeliac Disease and Irritable Bowel Syndrome. Our analysis reveals unique clustering patterns as well as spatial and temporal trends inherent to the considered GI diseases in terms of literature that has been accumulated so far. Although automated interpretation cannot replace human judgement, the developed workflow shows promising results and can be a useful tool in systematic literature reviews. The workflow is available at https://github.com/KociOrges/pytag.