title: Obstructive sleep apnea and risk of osteoporosis: a population-based cohort study in Taiwan.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) is associated with metabolic, endocrine, and cardiovascular diseases. It is characterized by repetitive episodes of apnea/hypopnea and hypoxia in tissues, which might also impact bone metabolism. This study investigates the possible association between OSA and osteoporosis.
  
  
  METHODS
  Random samples of 1 million individuals were collected from Taiwan's National Health Insurance database. A total of 1377 patients with newly diagnosed OSA from 2000 to 2008 were recruited and compared with a matched cohort of 20 655 patients without OSA. All patients were tracked until an osteoporosis diagnosis, death, or the end of 2011.
  
  
  RESULTS
  During the 6-year follow-up period, the incidence rates of osteoporosis in the OSA cohort and comparison group were 2.52 and 1.00 per 1000 person-years, respectively. Patients with OSA were found to be at 2.74 times the risk of osteoporosis than patients without OSA (95% confidence interval 1.69-4.44, P < .05), after adjustment for age, gender, diabetes, hypertension, coronary artery disease, obesity, stroke, hyperlipidemia, chronic kidney disease, gout, monthly income, and geographical location. Subgroup analysis showed that older patients and female patients had a higher risk for osteoporosis than their younger and male counterparts. Log-rank analysis revealed that patients with OSA patients had significantly higher cumulative incidence rates of osteoporosis than the comparison group (P < .0001).
  
  
  CONCLUSIONS
  People diagnosed with OSA are at increased risk for subsequent osteoporosis.
authors.affiliation: Division of Endocrinology and Metabolism (Y.-L.C., C.-W.C., C.-Y.Y., K.-J.T.), Department of Internal Medicine, and Department of Medical Research (S.-F.W., J.-J.W.), Chi Mei Medical Center, Tainan 710, Taiwan; Department of Hospital and Health Care Administration (S.-F.W.) and The Center of General Education (K.-J.T.), Chia Nan University of Pharmacy and Science, Tainan 717, Taiwan; and Department of Urology (Y.-C.S.), Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 833, Taiwan.
authors.forename: Yu-Li
authors.initials: YL
authors.lastname: Chen
authors.forename: Shih-Feng
authors.initials: SF
authors.lastname: Weng
authors.forename: Yuan-Chi
authors.initials: YC
authors.lastname: Shen
authors.forename: Chien-Wen
authors.initials: CW
authors.lastname: Chou
authors.forename: Chwen-Yi
authors.initials: CY
authors.lastname: Yang
authors.forename: Jhi-Joung
authors.initials: JJ
authors.lastname: Wang
authors.forename: Kai-Jen
authors.initials: KJ
authors.lastname: Tien
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000453:epidemiology*; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology*; D013624:Taiwan / Q000453:epidemiology