Relationship between serum endogenous estrogen and bone mass in pre and postmenopausal women.

2004 Fiscal Year Final Research Report Summary

• Project/Area Number: 14570349
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Public health/Health science
• Research Institution: Kobe City College of Nursing
• Principal Investigator: KASAMATSU Takahiro Kobe City College of Nursing, Department of Nursing, Professor, 看護学部, 教授 (20073695)
• Co-Investigator(Kenkyū-buntansha): YOSHIOKA Takayuki Kobe City College of Nursing, Department of Nursing, Lecturer, 看護学部, 講師 (90285354) ; NUMOTO Kyoko Kobe City College of Nursing, Department of Nursing, Professor, 看護学部, 教授 (00198558) ; YOSHIMURA Noriko Wakayama Medical College, Department of Medicine, Lecturer, 医学部, 講師 (60240355)
• Project Period (FY): 2002 – 2004
• Keywords: bone mass / sex steroids / estrogen / menopause / menstrual status / middle and elderly women

Research Abstract

The purpose of this study was to clarify the relationship between serum endogenous estrogen and bone mass in pre and postmenopausal female. Two hundred subjects, aged 40 to 79 years, were recruited randomly to give 50 persons in each of four age strata from a list of residents. The bone mass measurements of the lumbar spine and proximal femur were perfomed using dual X-ray absorptiometry. Total estradiol (total E2) and sex hormone-binding globulin(SHBG) were measured, and SHBG-unbound E2 (UBE2) was calculated.
Participants with ovariectomy or hysterectomy were excluded, and the remaining participants were categorized into four groups : premenopausal (n=38), perimenopausal (n=14), postmenopausal group 1 (5 years or less since menopause ; n=18), and postmenopausal group 2 (6 years or more since menopause ; n=74). The mean value of total E2 was highest in the premenopausal group (49.1p g/ml), followed by the perimenopausal group (26.4p g/ml), and the postmenopausal groups (0.83p g/ml in po stmenopausal group 1 and 0.96p g/ml in postmenopausal group 2). The mean values for UBE2 showed the same pattern across the groups. After the multiple regression analysis of bone mass and endogenous estrogens, in premenopausal women, there were no significant relations between bone mass and serum total E2 and UBE2. In perimenopausal women, however, serum total E2 and UBE2 were significantly correlated with trochanteric bone mass (p<0.05) ; and in postmenopausal group 2, they were significantly correlated with lumbar spine and Ward's triangle bone mass (p<0.01 at lumbar spine, p<0.05 at Ward's triangle). Concerning the association between bone mass and SHBG, in the premenopausal group, serum SHBG were negatively correlated with bone mass at the femoral neck (p<0.05). These findings suggest that the relations between bone mass and serum estrogen values differed by the menstrual status. Therefore, it seemed to have to consider the menstrual status, when the bone mass was evaluated in the serum estrogen.