title: The impact of medication on vitamin D status in older individuals.
abstract: OBJECTIVE
  Vitamin D deficiency and polypharmacy are common in the elderly. However, knowledge on the associations between the use of specific medicines and serum 25-hydroxyvitamin D (25(OH)D) is limited. The aim of this study was to (better) define the associations between the use of specific medicines and serum 25(OH)D.
  
  
  METHODS
  Two different cohorts (1995/1996 and 2002/2003) from the Longitudinal Aging Study Amsterdam (LASA) were used for cross-sectional analyses. LASA is based on an age and sex-stratified random sample of the Dutch older population. Study participants were aged 65-88 years in the first cohort (n = 1301) and 55-65 years in the second cohort (n = 736). Serum 25(OH)D of users of several groups of medicines were compared with levels of non-users using multiple linear regression analysis.
  
  
  RESULTS
  Of all participants, 75.4% (first cohort) and 61.1% (second cohort) were using at least one medicine. In both cohorts, the number of medicines was associated with lower serum 25(OH)D. In the first cohort, after adjustment for confounding, users of any kind of medicine, loop diuretics and inhaled corticosteroids (only men) had respectively 4.4 nmol/l (P<0.01), 4.7 nmol/l (P = 0.04) and 7.3 nmol/l (P = 0.02) lower serum 25(OH)D than non-users. In the second cohort, the use of oral antidiabetics, calcium-channel blockers and angiotensin-converting enzyme inhibitors was associated with respectively 7.4 nmol/l (P = 0.04), 7.7 nmol/l (P = 0.01) and 7.6 nmol/l (P<0.01) lower serum 25(OH)D.
  
  
  CONCLUSIONS
  These data show that users of several medicines have lower serum 25(OH)D than non-users. Vitamin D supplementation may be considered in patients with chronic use of medicines.
authors.affiliation: Department of Epidemiology and Biostatistics, EMGO Institute for Health and Care Research, VU University Medical Center, Van der Boechorststraat 7, Room A517, 1081 BT Amsterdam, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Sohl
authors.forename: N M
authors.initials: NM
authors.lastname: van Schoor
authors.forename: R T
authors.initials: RT
authors.lastname: de Jongh
authors.forename: O J
authors.initials: OJ
authors.lastname: de Vries
authors.forename: P
authors.initials: P
authors.lastname: Lips
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D064420:Drug-Related Side Effects and Adverse Reactions; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D004364:Pharmaceutical Preparations / Q000097:blood; D011446:Prospective Studies; D014807:Vitamin D / Q000037:antagonists & inhibitors* / Q000096:biosynthesis* / Q000097:blood; D014808:Vitamin D Deficiency / Q000139:chemically induced* / Q000175:diagnosis
chemical_list: D004364:Pharmaceutical Preparations; D014807:Vitamin D