title: Depressive symptoms are not associated with forearm bone accrual during adolescence.
abstract: Although depression has been associated to worst bone physical properties in adulthood, this study showed that depressive symptoms were not significantly associated to bone mineral density measured at the forearm during adolescence.
  
  
  OBJECTIVE
  Depressive conditions have been related to the reduction of bone mineral density (BMD) in adulthood. Though it is possible to hypothesize that depressive symptoms present similar effects in bone mineral accrual during adolescence, such association is poorly researched. Therefore, we aimed to study the relation between depressive symptoms and forearm BMD during adolescence.
  
  
  METHODS
  The study is based on the Epidemiological Health Investigation of Teenagers cohort that sampled adolescents born in 1990 and enrolled in public and private schools of Porto during the 2003/2004 academic year. At baseline (n = 2,160) and at 17 years of age (n = 1,716), depressive symptoms were evaluated using the Beck Depression Inventory-II (BDI-II). BMD (grams per square centimetre) was measured at the non-dominant forearm using dual-energy X-ray absorptiometry. Sex-specific crude and adjusted linear regression coefficients (β) and the corresponding 95 % confidence intervals (95 % CIs) were calculated to estimate the cross-sectional and prospective associations between depressive symptoms and forearm BMD.
  
  
  RESULTS
  In both sexes, in early and late adolescence, depressive symptoms presented no statistically significant association with forearm BMD (β Girls13 = 0.09, 95 % CI = -0.43 to 0.61; β Girls17 = 0.10, 95 % CI = -0.43 to 0.64; β Boys13 = -0.10, 95 % CI = -0.96 to 0.76; β Boys17 = 0.49, 95 % CI = -0.96 to 1.93). Similarly, there were no significant associations between depressive symptoms and the annual forearm BMD change during adolescence in girls and boys (β Girls_BDI-II_13-17_remained_lowest = -0.85, 95 % CI = -4.62 to 2.92 vs. β Girls_BDI-II_13-17_remained_highest = -1.87, 95 % CI = -5.06 to 1.31; β Boys_BDI-II_13-17_remained_lowest = 0.48, 95 % CI = -5.30 to 6.26 vs. β Boys_BDI-II_13-17_remained_highest = 1.36, 95 % CI = -3.25 to 5.97).
  
  
  CONCLUSIONS
  Depressive symptoms, with the range of severity observed in the general adolescent population, were not associated with changes in forearm bone mineral density during adolescence. Further research based on measurements of different skeletal sites is needed in order to detect a systemic effect of depression on growing bone.
authors.affiliation: Institute of Public Health of the University of Porto, Rua das Taipas, 135-139, 4050-600, Porto, Portugal, slourenco@med.up.pt.
authors.forename: Sara
authors.initials: S
authors.lastname: Lourenço
authors.forename: Raquel
authors.initials: R
authors.lastname: Lucas
authors.forename: Daniele Ferreira
authors.initials: DF
authors.lastname: da Silva
authors.forename: Elisabete
authors.initials: E
authors.lastname: Ramos
authors.forename: Henrique
authors.initials: H
authors.lastname: Barros
mesh_terms: D000293:Adolescent; D050280:Arm Bones / Q000502:physiology*; D015992:Body Mass Index; D015519:Bone Density / Q000502:physiology; D003430:Cross-Sectional Studies; D003863:Depression / Q000503:physiopathology*; D005260:Female; D005542:Forearm / Q000502:physiology*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012727:Sex Characteristics