Predictors of new fragility fractures after diagnosis of indolent systemic mastocytosis

Eveline van der Veer; Suzanne Arends; Sjoukje van der Hoek; Joris B Versluijs; Jan G R de Monchy; Joanna N G Oude Elberink; Jasper J van Doormaal

doi:10.1016/j.jaci.2014.05.003

Predictors of new fragility fractures after diagnosis of indolent systemic mastocytosis

J Allergy Clin Immunol. 2014 Dec;134(6):1413-1421. doi: 10.1016/j.jaci.2014.05.003. Epub 2014 Jun 27.

Authors

Eveline van der Veer¹, Suzanne Arends², Sjoukje van der Hoek³, Joris B Versluijs⁴, Jan G R de Monchy³, Joanna N G Oude Elberink⁵, Jasper J van Doormaal³

Affiliations

¹ Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands. Electronic address: e.van.der.veer@umcg.nl.
² Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
³ Allergy, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
⁴ Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
⁵ Allergy, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; GRIAC Research Institute, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.

PMID: 24985401
DOI: 10.1016/j.jaci.2014.05.003

Abstract

Background: Fragility fractures (FFxs) and osteoporosis occur frequently in patients with indolent systemic mastocytosis (ISM), even before 50 years of age.

Objective: We sought to develop a prediction model to identify individual patients with ISM at risk of new FFxs.

Methods: Data on lifetime fractures and trauma circumstances were collected from vertebral morphometry, patients' records, and questionnaires. Clinical, lifestyle, and bone characteristics were measured. Patients receiving treatment for osteoporosis before ISM diagnosis or with missing bone data were excluded from FFx risk assessment.

Results: In total, 389 lifetime fractures occurred in 127 of the 221 patients with ISM (age, 19-77 years), including 90 patients with 264 FFxs. Median follow-up after diagnosis was 5.4 years (range, 0.4-15.3 years), with 5- and 10-year FFx risks of 23% ± 3% and 31% ± 4%, respectively. Male sex, high levels of bone resorption (serum type I collagen C-telopeptide), low hip bone mineral density, absence of urticaria pigmentosa, and alcohol intake at the time of ISM diagnosis were independent predictors of future FFxs. The MastFx score, a prediction model using these 5 characteristics, showed good accuracy (area under the curve, 0.80) to determine the risk of new FFxs. QFracture, a validated risk scoring tool for persons aged 30 to 99 years, was not useful in patients with ISM.

Conclusion: The MastFx score distinguishes patients with ISM at high, intermediate, and low risk of new FFxs. The included characteristics sex, serum type I collagen C-telopeptide, hip bone mineral density, urticaria pigmentosa, and alcohol intake are easy to collect in clinical practice. The high occurrence of FFxs in patients with ISM underlines the importance of optimizing bone quality and early start of therapeutic prevention in patients at risk.

Keywords: Systemic mastocytosis; alcohol; bone mineral density; bone turnover markers; fracture risk scoring tool; fragility fractures; serum type I collagen C-telopeptide; sex; urticaria pigmentosa.

MeSH terms

Adult
Alcohol Drinking
Bone Density
Collagen Type I / blood
Female
Fractures, Bone / blood
Fractures, Bone / epidemiology*
Fractures, Bone / physiopathology
Hip / physiology
Humans
Male
Mastocytosis, Systemic / blood
Mastocytosis, Systemic / diagnosis
Mastocytosis, Systemic / epidemiology*
Mastocytosis, Systemic / physiopathology
Middle Aged
Models, Biological*
Peptides / blood
Risk Factors
Sex Factors
Urticaria Pigmentosa / epidemiology

Substances

Collagen Type I
Peptides
collagen type I trimeric cross-linked peptide