title: Increased risk of osteoporosis in patients with myasthenia gravis: a population-based cohort study.
abstract: OBJECTIVE
  To determine the risk of osteoporosis in patients with myasthenia gravis (MG) in a large cohort representing 99% of the population of Taiwan.
  
  
  METHODS
  Data from the Taiwan National Health Insurance Research Database were used to conduct retrospective cohort analyses. The study cohort consisted of 2,073 patients with MG who were 3-fold frequency-matched by age and sex and assigned the same index year as a comparison cohort without MG. Cox proportional hazard regression analysis was conducted to estimate the risk of osteoporosis.
  
  
  RESULTS
  The MG cohort had a 1.96-fold increased risk of developing osteoporosis compared with the comparison cohort (hazard ratio [HR] = 1.96, 95% confidence interval [CI] = 1.57-2.44). Patients with MG older than 30 years developed an increased risk of osteoporosis, with the highest risk in the age group from 30 to 44 years, compared with the control cohort. Corticosteroid-naïve patients with MG had a 1.52-fold increased risk of developing osteoporosis (HR = 1.52, 95% CI = 1.11-2.08), and the corticosteroid-treated cohort had a 2.37-fold increased risk of developing osteoporosis (HR = 2.37, 95% CI = 1.82-3.07).
  
  
  CONCLUSIONS
  This population-based retrospective cohort study provides evidence that MG is associated with a high risk of osteoporosis regardless of corticosteroid use.
authors.affiliation: From the Department of Neurology (J.-H.Y., H.-C.C.) and Department of Nuclear Medicine and PET Center (Y.-K.C.), Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; Management Office for Health Data (H.-J.C.), Graduate Institute of Clinical Medical Science and School of Medicine (C.-H.K.), College of Medicine (H.-J.C.), and Department of Nuclear Medicine and PET Center (C.-H. K.), China Medical University Hospital, Taichung, Taiwan; and School of Medicine (J.-H.Y., H.-C.C., Y.-K.C.), Fu Jen Catholic University, New Taipei City, Taiwan.
authors.forename: Jiann-Horng
authors.initials: JH
authors.lastname: Yeh
authors.affiliation: From the Department of Neurology (J.-H.Y., H.-C.C.) and Department of Nuclear Medicine and PET Center (Y.-K.C.), Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; Management Office for Health Data (H.-J.C.), Graduate Institute of Clinical Medical Science and School of Medicine (C.-H.K.), College of Medicine (H.-J.C.), and Department of Nuclear Medicine and PET Center (C.-H. K.), China Medical University Hospital, Taichung, Taiwan; and School of Medicine (J.-H.Y., H.-C.C., Y.-K.C.), Fu Jen Catholic University, New Taipei City, Taiwan.
authors.forename: Hsuan-Ju
authors.initials: HJ
authors.lastname: Chen
authors.affiliation: From the Department of Neurology (J.-H.Y., H.-C.C.) and Department of Nuclear Medicine and PET Center (Y.-K.C.), Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; Management Office for Health Data (H.-J.C.), Graduate Institute of Clinical Medical Science and School of Medicine (C.-H.K.), College of Medicine (H.-J.C.), and Department of Nuclear Medicine and PET Center (C.-H. K.), China Medical University Hospital, Taichung, Taiwan; and School of Medicine (J.-H.Y., H.-C.C., Y.-K.C.), Fu Jen Catholic University, New Taipei City, Taiwan.
authors.forename: Yen-Kung
authors.initials: YK
authors.lastname: Chen
authors.affiliation: From the Department of Neurology (J.-H.Y., H.-C.C.) and Department of Nuclear Medicine and PET Center (Y.-K.C.), Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; Management Office for Health Data (H.-J.C.), Graduate Institute of Clinical Medical Science and School of Medicine (C.-H.K.), College of Medicine (H.-J.C.), and Department of Nuclear Medicine and PET Center (C.-H. K.), China Medical University Hospital, Taichung, Taiwan; and School of Medicine (J.-H.Y., H.-C.C., Y.-K.C.), Fu Jen Catholic University, New Taipei City, Taiwan.
authors.forename: Hou-Chang
authors.initials: HC
authors.lastname: Chiu
authors.affiliation: From the Department of Neurology (J.-H.Y., H.-C.C.) and Department of Nuclear Medicine and PET Center (Y.-K.C.), Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; Management Office for Health Data (H.-J.C.), Graduate Institute of Clinical Medical Science and School of Medicine (C.-H.K.), College of Medicine (H.-J.C.), and Department of Nuclear Medicine and PET Center (C.-H. K.), China Medical University Hospital, Taichung, Taiwan; and School of Medicine (J.-H.Y., H.-C.C., Y.-K.C.), Fu Jen Catholic University, New Taipei City, Taiwan. d10040@mail.cmuh.org.tw.
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Kao
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000367:Age Factors; D015331:Cohort Studies; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000188:drug therapy / Q000453:epidemiology*; D010024:Osteoporosis / Q000453:epidemiology* / Q000209:etiology; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology
chemical_list: D000305:Adrenal Cortex Hormones