Nutritional Status of CF Children Linked to Teenage-onset Diabetes
Children with cystic fibrosis (CF) who gain less than 2.5 kg (or 5.5 lbs) per year between the ages of five and 10 are nine times more likely to develop cystic fibrosis-related diabetes (CFRD) in adolescence, a new study reports.
The findings highlight the need to monitor closely the nutritional status of younger patients to identify those at risk of developing CFRD in their teens.
The study, “Nutritional status between 5-10 years is associated with cystic fibrosis-related diabetes in adolescence,” was published in the journal Pediatric Pulmonology.
Nearly half of all CF patients develop diabetes as a result of the disease, although the condition is rare before puberty. As most people with CFRD do not show symptoms of diabetes, the Cystic Fibrosis Foundation and the International Society of Pediatric & Adolescent Diabetes recommend annual screening of CFRD for patients 10 years or older.
CFRD is associated with poorer lung function, slower growth, weight loss (poor nutritional status), and higher mortality. Therefore, early diagnosis and appropriate treatment are essential.
Now, researchers from the University of Arkansas for Medical Sciences searched for an association between nutritional indicators in young children with a later diagnosis of CFRD, and hypothesized that patients with CFRD possibly gained less weight and height between the ages of five and 10 than young CF patients who did not develop CFRD later.
Data were collected and analyzed from the hospital records of patients followed at the CF Center at the Arkansas Children’s Hospital. Patients were between the ages of 10 and 18 years by Oct. 31, 2019, and had at least one routine oral glucose tolerance test to screen for CFRD within one year before this date. The test measures the body’s response to glucose.
Information on height, weight, and acute CF exacerbations was obtained between the ages of five and 10. Lung function was measured at age 10 based on the forced expiratory volume in one second and forced vital capacity parameters.
A total of 62 patients were ultimately included in the study. Of these, seven patients were diagnosed with CFRD at 10 years of age. The mean age of patients in the CFRD group was 15.8 years versus 14.3 years in those in the non-CFRD group (55 patients).
At age 10, no differences were found between groups in pancreas function status, lung function, acute CF exacerbations, and percentage of patients on modulator therapy or with Pseudomonas infection.
Likewise, at five and 10 years of age, weight, height, and body mass index (BMI, an indicator of body fat), were similar between patients with and without CFRD.
However, patients with CFRD at age 10 had statistically lower weight percentiles and BMI percentiles compared to the non-CFRD group. Percentiles show where children are in comparison to others of the same sex and age.
Next, the researchers determined the annualized weight gain rate and growth velocity. These were calculated by dividing the difference of weight or height by the interval time measured in years between the two visits at ages five and 10.
Patients with CFRD had a considerably lower average weight gain (2.2 kg/year vs. 3.3 kg/year for non-CFRD), and average growth velocity (5 cm/year for CFRD vs. 5.7 cm/year for non-CFRD) between the ages of five and 10.
Additionally, the researchers found that patients with a weight gain under 2.5 kg/year between ages five and 10 were nine times more likely to develop CFRD later.
“Patients who later developed CFRD had significantly lower weight gain rate and height growth between 5 and 10 years of age than those without diabetes,” the researchers wrote.
“Close monitoring of nutritional status … before age 10 years may help identify CF patients at-risk of developing CFRD,” they added.
The team noted that the small number of patients in the CFRD group could be a limitation of the study and that additional information on their social and economic status, eating habits, and mid-parental height (a child’s predicted adult height based on the heights of the parents) was lacking.
Thus, “future studies using more extensive databases will be required to validate our findings,” the researchers wrote.