gms | German Medical Science

Objectives: X-linked Hypophosphatemia (XLH) is a rare bone disease characterized by renal phosphate-wasting due to an excess of FGF23, a hormone that reduces serum levels of phosphorus and vitamin D. XLH can cause bone deformity, which tend to appear when children begin to grow. Accordingly, incident XLH patients are expected to be children. Previous SHI claims data analyses showed the mean age of 55 years of incident XLH patients. Hence, further analysis for the detection of incident XLH children was conducted.

Method: Based on the retrospective analysis of a six-year (2010-2015) database from the German SHI system, a representative sample of ~4 million insurant was obtained, representing approx. 5.5 % of the total German population. Patients received at least one full or semi-residential inpatient diagnosis or two confirmed outpatient diagnoses in different quarters of the year (E83.30 ICD-10 GM) and a continuous insurance coverage, except deceased patients. For detecting children with XLH different combinations of diagnoses, medication and procedures, associated with XLH, were analysed.

Results: 136 patients with initial hereditary hypophosphatemia were found, which result in 2,176 XLH patients projected on the German population. The share of children amounts 17% of this cohort, whereof one third was found in the additional detection and had no coded XLH diagnosis. They were detected by sequelae of rickets (E64.3) as main diagnosis, followed by short stature (E34.3) and infantile idiopathic scoliosis (M41.0). Up to 40% of all XLH patients (independent of age) received defined specific medication (hormone or vitamins). Every second patient aged < 18 had no specific medication documented.

Conclusions: Further analysis revealed that a high share has no correct diagnosis documented. Up to 60% of all XLH patients are not treated sufficiently (independent of age) indicating a gap of care of XLH patients and a need for further disease awareness.