title: Association between osteoporosis and urinary calculus: evidence from a population-based study.
abstract: CONCLUSIONS
  This population-based case-control analysis investigated the association between osteoporosis and prior urinary calculus (UC) in Taiwan. We succeeded in detecting an association between osteoporosis and prior UC (adjusted odds ratio = 1.66). This association was consistent and significant regardless of stone location.
  
  
  BACKGROUND
  UC has been demonstrated to be a risk factor for osteoporotic fractures, but no studies to date have directly investigated the association between UC and osteoporosis. This case-control analysis aimed to investigate the association of osteoporosis with prior UC using a population-based dataset in Taiwan.
  
  
  METHODS
  We first identified 39,840 cases ≥40 years who received their first-time diagnosis of osteoporosis between 2002 and 2009 and then randomly selected 79,680 controls. We used conditional logistic regression analyses to compute the odds ratio (OR) and the corresponding 95 % confidence interval (CI) for having been previously diagnosed with UC between cases and controls.
  
  
  RESULTS
  The OR of having been previously diagnosed with UC for patients with osteoporosis was 1.66 (95 % CI = 1.59-1.73) when compared to controls after adjusting for geographic location, urbanization level, type I diabetes mellitus, coronary heart disease, hyperlipidemia, rheumatoid arthritis, stroke, renal disease, Parkinson's disease, hyperthyroidism, chronic hepatopathy, Cushing's syndrome, malabsorption, gastrectomy, obesity, and alcohol abuse/alcohol dependence syndrome. The results consistently showed that osteoporosis was significantly associated with a previous diagnosis of UC regardless of stone location; the adjusted ORs of prior kidney calculus, ureter calculus, bladder calculus, and unspecified calculus when compared to controls were 1.71 (95 % CI = 1.61-1.81), 1.60 (95 % CI = 1.47-1.74), 1.59 (95 % CI = 1.23-2.04), and 1.69 (95 % CI = 1.59-1.80), respectively.
  
  
  CONCLUSIONS
  This study succeeded in detecting an association between osteoporosis and prior UC. In addition, our findings were consistent and significant regardless of stone location.
authors.affiliation: School of Public Health, Taipei Medical University, 250 Wu-Hsing St, Taipei, 110, Taiwan.
authors.forename: J J
authors.initials: JJ
authors.lastname: Keller
authors.forename: C-C
authors.initials: CC
authors.lastname: Lin
authors.forename: J-H
authors.initials: JH
authors.lastname: Kang
authors.forename: H-C
authors.initials: HC
authors.lastname: Lin
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015897:Comorbidity; D016208:Databases, Factual; D019317:Evidence-Based Medicine / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000150:complications* / Q000453:epidemiology; D012959:Socioeconomic Factors; D013624:Taiwan / Q000453:epidemiology; D014545:Urinary Calculi / Q000150:complications* / Q000453:epidemiology