Rapid early increase in BMI is associated with impaired longitudinal growth in children with cystic fibrosis

Abstract

Background We aimed to assess whether final height in children with cystic fibrosis (CF) is affected by body mass index (BMI), BMI increase, pulmonary function, and cystic fibrosis‐related diabetes (CFRD). Study design A longitudinal, retrospective study was performed in a cohort of 57 patients with CF (30 boys, 27 girls) born between 1997 and 2001. Height and weight were recorded annually from ages 0.5 to 10 years and biannually up to the age of 18. Measurements were converted to height‐for‐age‐adjusted‐for‐target‐height (HFA‐TH) and BMI‐for‐age z‐scores. Analyses were performed using the independent t tests and the Pearson's correlation. Results For both boys and girls, HFA‐TH and BMI‐for‐age z‐scores were significantly lower in the first year of life, these scores increased rapidly until the age of 11 and 8 years, respectively. In boys, HFA‐TH z‐scores declined during puberty, with subsequently significantly impaired final height (z‐score, −0.56, n = 30, standard deviation [SD] = 0.81, P = 0.001). In girls, HFA‐TH z‐scores briefly declined after the age of 8 years, but then increased to a z‐score of −0.21 (n = 27, SD = 0.87) at age 18, which is not significantly lower than the national average (P = 0.22). Pulmonary function and the presence of CFRD were not associated with final height. However, rapid BMI increase between ages 1 and 6 was negatively associated with final height in boys (n = 29, r =−0.420; P = 0.023) and girls (n = 25, r =−0.466; P = 0.019). Conclusions In boys and girls, early BMI increase was associated with impaired final height. We suggest that early childhood serves as a “window” in which nutritional variations may program subsequent growth. Further refinement of nutritional strategies could be needed.

BMI increase during early childhood in boys with cystic fibrosis and early adrenarche

“…To our knowledge, this is the first study to investigate early adrenarche in relation to BMI change in boys with CF. These results cautiously support our hypothesis that impaired height in boys with CF might be the result of an early adrenal activation due to (too) rapid BMI increase in early childhood, a phenomenon we described in our earlier study, 7 potentially leading to earlier skeletal maturation and closure of epiphyseal growth plates.…”

“…Second, the time of follow up was short and no patient had reached final height. Although it is assumed in prior research 7 that the early adrenarche with accelerated bone age results in impaired final height, this has not been proven yet in this cohort.…”

Cystic fibrosis year in review 2019: Section 3 multisystem‐based care and research

“…29 Another single-center analysis of 57 children born between 1997 and 2001 demonstrated a lower height and BMI for age in first year of life with continued impairment in final height (height for age z-score −0.56). 30 Interestingly, rapid BMI increase during early childhood (1-6 years of age) had a negative association with final height, while neither FEV1 nor cystic fibrosis-related diabetes (CFRD) had any associated with final height. 31 While BMI is positively correlated with FEV1 in CF, the contribution of body composition to overall health has had less scrutiny.…”

“…National databases in Denmark and Wales were used to better understand this phenomenon, finding that earlier birth (by 3–4 days) accounted for only 35%–39% of the difference in weight 29 . Another single‐center analysis of 57 children born between 1997 and 2001 demonstrated a lower height and BMI for age in first year of life with continued impairment in final height (height for age z‐score −0.56) 30 . Interestingly, rapid BMI increase during early childhood (1–6 years of age) had a negative association with final height, while neither FEV1 nor cystic fibrosis‐related diabetes (CFRD) had any associated with final height 31 …”

Quality of anthropometric data measured in children and adolescents with cystic fibrosis: a scoping review

“…The most commonly cited reference populations were those of the Centers for Disease Control and Prevention (CDC) 14,[19][20][21]27,29,31,33,[40][41][42] and of the World Health Organization (WHO); 18,[22][23][24][25][26]37 however, references were also made to specific populations such as Italian, 11 Greek, 15 Egyptian, 16 Dutch, 35,38 and British. 39 The cutoff points adopted by the…”