19191
document
[ Long-term effects of 7-year growth hormone substitution on bone metabolism , bone density , and bone quality in growth hormone-deficient adults ] . BACKGROUND AND PURPOSE Subnormal bone mineral density ( BMD ) and increased fracture risk are described in patients with growth hormone deficiency ( GHD ) . Growth hormone ( GH ) has been reported to have beneficial effects on bone in GHD . The aim of this study was to investigate the long-term effects of GH replacement therapy on bone metabolism , BMD , and bone quality in patients with GHD . PATIENTS AND METHODS 20 adult patients with GHD ( eleven male , nine female , mean age 42.5 years ) were included in the study and randomized to either GH or placebo in a dose of 0.25 U/kg body weight/week . After 6 months all patients received GH . After a 1-year double-blind , placebo-controlled study the patients were followed for another 72 months in an open study . The patients were compared to 20 age- und sex-matched healthy controls . Bone turnover was determined by ICTP ( type I collagen carboxyterminal cross-linked telopeptide ) as parameter of bone resorption and PICP ( carboxyterminal propeptide of type I procollagen ) as marker of bone formation . BMD was measured at the lumbar spine by dual-photon absorptiometry ( DPA ) and at the forearm by single-photon absorptiometry ( SPA ) . Apparent phalangeal ultrasound transmission velocity ( APU ) was assessed as parameter of bone quality independent of BMD . RESULTS At the beginning of the study BMD at both measuring sites was lower in patients with GHD than in healthy controls . During the 1st year of GH replacement therapy BMD decreased , followed by a continuous increase in BMD ( about 12 % ) up to 60 months which remained unchanged thereafter , building up a plateau . After 72 months no significant difference between the patients and the healthy controls could be detected . Concerning parameters of bone turnover , first ICTP as marker of bone resorption showed a significant increase , later on the marker of bone formation increased as well . APU decreased during the first 6 months of treatment , but had returned to its baseline value after 24 months and remained unchanged throughout the rest of the study . CONCLUSION BMD is subnormal in adults with GHD . GH replacement therapy stimulates bone turnover in patients with GHD and in the long term such stimulation results in an increased BMD . Thereby , GH shows a triphasic action on BMD : an initial decrease in BMD during the 1st year , followed by a continuous increase in BMD with buildup of a stable plateau after 60 months . The newly formed bone seems to have normal bone elasticity .
19192
Intervention_Pharmacological
growth hormone substitution
19193
Intervention_Pharmacological
Growth hormone ( GH )
19194
Intervention_Pharmacological
GH replacement therapy
19195
Intervention_Pharmacological
GH
19196
Intervention_Control
placebo
19197
Intervention_Pharmacological
GH
19198
Intervention_Control
placebo-controlled
19199
Intervention_Pharmacological
GH
19200
Intervention_Pharmacological
GH
19201
Outcome_Other
bone metabolism
19202
Outcome_Other
bone density
19203
Outcome_Other
bone quality
19204
Outcome_Physical
Subnormal bone mineral density ( BMD )
19205
Outcome_Physical
increased fracture risk
19206
Outcome_Physical
effects on bone
19207
Outcome_Physical
bone metabolism
19208
Outcome_Physical
BMD
19209
Outcome_Physical
bone quality
19210
Outcome_Physical
Bone turnover
19211
Outcome_Physical
BMD
19212
Outcome_Physical
Apparent phalangeal ultrasound transmission velocity ( APU )
19213
Outcome_Physical
BMD
19214
Outcome_Physical
BMD
19215
Outcome_Physical
BMD
19216
Outcome_Physical
bone turnover
19217
Outcome_Other
first ICTP
19218
Outcome_Other
bone resorption
19219
Outcome_Physical
marker of bone formation
19220
Outcome_Physical
APU
19221
Outcome_Physical
BMD
19222
Outcome_Physical
bone turnover
19223
Outcome_Physical
BMD
19224
Outcome_Physical
BMD
19225
Outcome_Physical
BMD
19226
Outcome_Physical
BMD
19227
Outcome_Physical
normal bone elasticity
19228
Participant_Condition
growth hormone-deficient
19229
Participant_Age
adults
19230
Participant_Condition
growth hormone deficiency ( GHD )
19231
Participant_Condition
GHD
19232
Participant_Sample-size
20
19233
Participant_Age
adult
19234
Participant_Condition
GHD
19235
Participant_Sample-size
eleven
19236
Participant_Sample-size
nine
19237
Participant_Age
42.5 years )