Risk of fracture in patients with muscular dystrophies.
The aim of the study was to determine fracture risk in incident muscular dystrophy (MD) patients. Patients with MD are at a 1.4-fold increased risk of fracture as compared with population-based control patients. Risk further increased among elderly and female patients and among patients exposed to oral glucocorticoids.


BACKGROUND
Muscular dystrophies (MDs) are inherited diseases causing muscle weakness and thereby increase the risk of falling and detrimental effects on bone. Both are recognised risk factors for fracture. Therefore, the aim of this study was to determine the hazard ratio of fracture in patients with MD.


METHODS
We conducted a retrospective cohort study using the UK General Practice Research Database (1987-2012). Each patient with MD was matched by year of birth, sex and practice to up to six patients without a history of MD. Outcome measure was all fractures.


RESULTS
As compared with control patients, risk of any fracture was statistically significantly increased in MD patients (adjusted hazard ratio [AHR], 1.40; 95 % confidence interval [CI], 1.14-1.71). An increased risk of fracture was observed among MD patients with female gender (AHR, 1.78; 95 % CI, 1.33-2.40) and an increasing age as compared with control patients. Stratification to Duchenne MD showed no association with fracture, whereas risk of fracture was increased twofold among patients with myotonic dystrophy (AHR, 2.34; 95 % CI, 1.56-3.51). MD patients had an almost tripled risk of fracture when they used oral glucocorticoids in the previous 6 months as compared to non-users with MD.


CONCLUSIONS
Patients with MD are at a 1.4-fold increased risk of fracture as compared with population-based control patients. Especially in older age groups and female gender, the fracture risk of MD versus non-MD patients is increased, whereas exposure to glucocorticoids further increased fracture risk among MD patients.
Utrecht Institute for Pharmaceutical Sciences, Universiteit Utrecht, Utrecht, Netherlands.
S
S
Pouwels
A
A
de Boer
H G M
HG
Leufkens
W E J
WE
Weber
C
C
Cooper
H A W
HA
van Onzenoort
F
F
de Vries
D000328:Adult; D017677:Age Distribution; D015897:Comorbidity; D016208:Databases, Factual; D004363:Drug Utilization / Q000706:statistics & numerical data; D005260:Female; D050723:Fractures, Bone / Q000453:epidemiology / Q000209:etiology*; D005938:Glucocorticoids / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009136:Muscular Dystrophies / Q000150:complications* / Q000453:epidemiology; D020388:Muscular Dystrophy, Duchenne / Q000150:complications / Q000453:epidemiology; D009223:Myotonic Dystrophy / Q000150:complications / Q000453:epidemiology; D058866:Osteoporotic Fractures / Q000453:epidemiology / Q000209:etiology; D012189:Retrospective Studies; D018570:Risk Assessment; D017678:Sex Distribution; D006113:United Kingdom / Q000453:epidemiology
D005938:Glucocorticoids