title: Factors associated with bone mineral density loss in patients with spondyloarthropathies: A 4-year follow-up study.
abstract: OBJECTIVE
  To explore the relationship between laboratory, functional, disease activity markers and bone mineral density (BMD) loss in patients with spondyloarthropathies (SpAs).
  
  
  METHODS
  A cohort of 41 SpA patients were followed up for 4 years. Disease activity indices, spinal mobility and laboratory tests, BMD using were monitored at the baseline and 4-year follow-up. The 4% BMD loss at either of the proximal femurs was defined as significant.
  
  
  RESULTS
  Over the 4-year study period, 27% of SpA patients experienced femoral BMD loss. Baseline BMD>0.85g/cm(2) (p=0.011) was the baseline factor associated with BMD loss at 4-year follow-up. Several clinical and functional tests were helpful in identifying the BMD loss at follow-up: CRP>15.6mg/L (sens. 91%, spec. 70%), ESR>29mm/h (sens. 82%, spec. 73%), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI)>4.75 (sens. 91%, spec. 62%). At follow-up anti-TNFα treatment history, stable or improved lateral flexion and intermalleolar distance (NPV, accordingly, 95%, 88% and 87%), made BMD loss unlikely. Deterioration of the physician assessment of global disease activity (PAGDA) score from baseline to follow-up was a remarkable predictor of BMD loss (PPV=0.83), while stable or improved score excluded the BMD loss (NPV=0.83). According to multiple logistic regression analysis, baseline BMD value and follow-up CRP levels, when considered together, identify BMD status correctly in 85% of SpA patients (Nagelkerke R(2)=0.676).
  
  
  CONCLUSIONS
  Baseline BMD, anti-TNFα treatment, PAGDA score, spinal mobility tests and disease activity markers are useful factors in predicting the BMD loss in SpA patients and can provide surrogate information on BMD status.
authors.affiliation: Centre of Family Medicine, Vilnius University, Vilnius, Lithuania. Electronic address: linaven@gmail.com.
authors.forename: Lina
authors.initials: L
authors.lastname: Vencevičienė
authors.affiliation: Centre of Rheumatology, Vilnius University, Vilnius, Lithuania; Centre for Innovative Medicine, State Research Institute, Vilnius, Lithuania.
authors.forename: Irena
authors.initials: I
authors.lastname: Butrimienė
authors.affiliation: Centre of Traumatology, Orthopedics and Plastic and Reconstructive Surgery, Vilnius University, Vilnius, Lithuania.
authors.forename: Rimantas
authors.initials: R
authors.lastname: Vencevičius
authors.affiliation: Centre of Cardiology and Angiology, Vilnius University, Vilnius, Lithuania.
authors.forename: Eglė
authors.initials: E
authors.lastname: Sadauskienė
authors.affiliation: Centre of Family Medicine, Vilnius University, Vilnius, Lithuania.
authors.forename: Vytautas
authors.initials: V
authors.lastname: Kasiulevičius
authors.affiliation: Centre of Internal Medicine, Vilnius University, Vilnius, Lithuania.
authors.forename: Virginijus
authors.initials: V
authors.lastname: Šapoka
mesh_terms: D000328:Adult; D000368:Aged; D015519:Bone Density; D002097:C-Reactive Protein / Q000032:analysis; D005260:Female; D005269:Femur; D005500:Follow-Up Studies; D006801:Humans; D008097:Lithuania / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000453:epidemiology*; D012307:Risk Factors; D012720:Severity of Illness Index; D025242:Spondylarthropathies / Q000188:drug therapy / Q000453:epidemiology*; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors; D055815:Young Adult
chemical_list: D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein
keywords: Anti-TNFα; Bone mineral density; Spondyloarthropathies