Association between insulin growth factor-1, bone mineral density, and frailty phenotype in children with chronic kidney disease.
BACKGROUND
This cohort study investigates the association between insulin growth factor-1 (IGF-1), bone mineral density, and frailty phenotype in children with chronic kidney disease (CKD).


METHODS
Forty-six patients (median age 14.5 years) were prospectively enrolled. Frailty phenotype was defined as the presence ≥ 3 of the following indicators: suboptimal growth/weight gain (body mass index height age < 5th percentile or height < 3rd percentile or loss of ≥ 10 percentiles/year in at least one parameter), low muscle mass (lean tissue mass height age < 5th percentile or loss of ≥ 10 percentiles/year), general fatigue reported by parent or child, and C-reactive protein > 3 mg/l. Lumbar bone mineral apparent density (LBMAD) was measured by dual-energy X-ray absorptiometry, body composition by bioimpedance spectroscopy, and IGF-1 by enzyme-labeled chemiluminescent immunometric assay.


RESULTS
Frailty phenotype (seven patients) was more frequent in advanced CKD (estimated glomerular filtration rate < 30 ml/min/1.73m2) (p = 0.014). IGF-1 and LBMAD z-scores were lower in patients with suboptimal growth/weight gain (14 patients) (p = 0.013, p = 0.012), low muscle mass (nine patients) (p = 0.001, p = 0.009), and general fatigue (eight patients) (p < 0.001, p = 0.004). IFG-1 and LBMAD z-scores were associated with frailty phenotype (OR 0.109, 95% CI 0.015-0.798 and OR 0.277, 95% CI 0.085-0.903) after adjustment for CKD stage. IGF-1 z-score was associated with LBMAD < 5th percentile (six patients) (OR 0.020, 95% CI 0.001-0.450) after adjustment for CKD stage. The association between LBMAD and frailty phenotype lost significance after adjustment for IGF-1.


CONCLUSION
Frailty phenotype is more frequent in advanced pediatric CKD. IGF-1 is negatively associated with frailty phenotype and interferes in the association between frailty and LBMAD.
['Karava|Vasiliki|V|http://orcid.org/0000-0003-3638-5179', 'Dotis|John|J|', 'Christoforidis|Athanasios|A|', 'Liakopoulos|Vassilios|V|', 'Kondou|Antonia|A|', 'Tsigaras|Georgios|G|', 'Tsioni|Konstantina|K|', 'Kollios|Konstantinos|K|', 'Printza|Nikoleta|N|']
Insulin growth factor-1 Frailty Children Chronic kidney disease Muscle mass Fatigue Bone mineral apparent density