title: Bone mineral density in patients on home parenteral nutrition: a follow-up study.
abstract: OBJECTIVE
  The variations of bone mineral density (BMD) during home parenteral nutrition (HPN) and their relationship with general, life style, primary disease and HPN risk factors were investigated by a follow-up study.
  
  
  METHODS
  Patients who had BMD assessment in a previous cross-sectional survey underwent a 2nd BMD at femoral neck (FN) and lumbar spine (LS). Data about risk factors were collected by a structured questionnaire. BMD Z-score (number of standard deviations from normal values corrected for sex and age) and the annualized percent BMD change were analysed.
  
  
  RESULTS
  Sixty-five adult patients were enrolled (follow-up: 18.1+/-5.5 months). The mean BMD Z-score significantly increased at the LS (P = 0.040) and remained unchanged at FN. In multiple regression analysis, the variations of the LS Z-score during HPN negatively correlated with the female sex (P = 0.021) and the age at starting HPN (P = 0.022). The analysis of the annualized percent BMD change confirmed the results obtained by the analysis of the Z-score. No factor was associated with BMD variation at FN.
  
  
  CONCLUSIONS
  HPN was not associated with a decrease of BMD in most of the patients; LS BMD Z-score variations were related to general risk factors rather than to HPN factors, showing a negative association with age and female sex.
authors.affiliation: Department of Internal Medicine and Gastroenterology, St. Orsola Malpighi Hospital, University of Bologna, Via Massarenti 9, 40138 Bologna, Italy. loris.pironi@unibo.it
authors.forename: Loris
authors.initials: L
authors.lastname: Pironi
authors.forename: Lone
authors.initials: L
authors.lastname: Tjellesen
authors.forename: Antonella
authors.initials: A
authors.lastname: De Francesco
authors.forename: Marek
authors.initials: M
authors.lastname: Pertkiewicz
authors.forename: A M Antonio M
authors.initials: AM
authors.lastname: Morselli Labate
authors.forename: Michael
authors.initials: M
authors.lastname: Staun
authors.forename: Jerzy
authors.initials: J
authors.lastname: Przedlacki
authors.forename: Antonella
authors.initials: A
authors.lastname: Lezo
authors.forename: Paolo
authors.initials: P
authors.lastname: Orlandoni
authors.forename: Francesco
authors.initials: F
authors.lastname: Pasanisi
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000367:Age Factors; D000368:Aged; D015519:Bone Density / Q000187:drug effects; D001847:Bone Diseases / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging; D005500:Follow-Up Studies; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D016331:Parenteral Nutrition, Home / Q000009:adverse effects; D015995:Prevalence; D012044:Regression Analysis; D012307:Risk Factors; D012737:Sex Factors; D011795:Surveys and Questionnaires