title: Bone Mineral Density in Sjögren Syndrome Patients with and Without Distal Renal Tubular Acidosis.
abstract: Primary Sjögren's syndrome (pSS) can be complicated by distal renal tubular acidosis (dRTA), which may contribute to low bone mineral density (BMD). Our objective was to evaluate BMD in pSS patients with and without dRTA as compared with healthy controls. BMD of lumbar spine (LS) and femoral neck (FN) was measured in 54 pSS patients and 162 healthy age- and sex-matched controls by dual-energy X-ray absorptiometry (DXA). dRTA was defined as inability to reach urinary pH <5.3 after an ammonium chloride (NH4Cl) test. LS- and FN-BMD were significantly higher in pSS patients compared with controls (1.18 ± 0.21 g/cm(2) for patients vs. 1.10 ± 0.18 g/cm(2) for controls, P = 0.008 and 0.9 ± 0.16 g/cm(2) for patients vs. 0.85 ± 0.13 g/cm(2) for controls, P = 0.009, respectively). After adjustment for BMI and smoking, the LS- and FN-BMD remained significantly higher. Patients with dRTA (N = 15) did not have a significantly different LS- and FN-BMD compared with those without dRTA (N = 39) after adjustment for BMI, age, and gender. Thirty-seven (69 %) pSS patients were using hydroxychloroquine (HCQ). Unexpectedly, pSS patients had a significantly higher LS- and FN-BMD compared with healthy controls. Patients with dRTA had similar BMD compared with patients without dRTA. We postulate that an explanation for the higher BMD in pSS patients may be the frequent use of HCQ.
authors.affiliation: Division of Clinical Immunology, Department of Internal Medicine, PO Box 2040, Room D-419, 3000 CA, Rotterdam, The Netherlands. t.both.1@erasmusmc.nl.
authors.forename: Tim
authors.initials: T
authors.lastname: Both
authors.affiliation: Department of Endocrinology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: M Carola
authors.initials: MC
authors.lastname: Zillikens
authors.affiliation: Department of Nephrology & Transplantation, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Ewout J
authors.initials: EJ
authors.lastname: Hoorn
authors.affiliation: Department of Nephrology & Transplantation, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Robert
authors.initials: R
authors.lastname: Zietse
authors.affiliation: Division of Clinical Immunology, Department of Internal Medicine, PO Box 2040, Room D-419, 3000 CA, Rotterdam, The Netherlands.|Department of Immunology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Jan A M
authors.initials: JA
authors.lastname: van Laar
authors.affiliation: Division of Clinical Immunology, Department of Internal Medicine, PO Box 2040, Room D-419, 3000 CA, Rotterdam, The Netherlands.|Department of Immunology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Virgil A S H
authors.initials: VA
authors.lastname: Dalm
authors.affiliation: Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Cornelia M
authors.initials: CM
authors.lastname: van Duijn
authors.affiliation: Department of Immunology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Marjan A
authors.initials: MA
authors.lastname: Versnel
authors.affiliation: Department of Immunology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Naomi I
authors.initials: NI
authors.lastname: Maria
authors.affiliation: Division of Clinical Immunology, Department of Internal Medicine, PO Box 2040, Room D-419, 3000 CA, Rotterdam, The Netherlands.|Department of Immunology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: P Martin
authors.initials: PM
authors.lastname: van Hagen
authors.affiliation: Division of Clinical Immunology, Department of Internal Medicine, PO Box 2040, Room D-419, 3000 CA, Rotterdam, The Netherlands.|Department of Immunology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Paul L A
authors.initials: PL
authors.lastname: van Daele
mesh_terms: D015502:Absorptiometry, Photon; D000141:Acidosis, Renal Tubular / Q000209:etiology*; D000328:Adult; D000368:Aged; D015519:Bone Density / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012859:Sjogren's Syndrome / Q000150:complications*
keywords: Bone mineral density; DEXA scan; Distal renal tubular acidosis; Hydroxychloroquine; Sjögren syndrome