Long-term hormone replacement therapy delays the age related progression of carotid intima-media thickness in healthy postmenopausal women

Objectives: Carotid intima-media thickness (IMT) is an appropriate intermediate end point to investigate clinically relevant effects on atherogenesis. The study objective was to clarify whether long-term hormone replacement therapy (HRT) modifies the progress of age-related IMT in healthy postmenopausal Japanese women. Methods: One hundred and eighty-eight healthy postmenopausal women aged 42-69 years were recruited into the retrospective study. IMT was measured by B-mode real-time ultrasound in the following three groups of patients. One hundred and fifteen women who were prescribed estrogen plus progestin or estrogen alone were classified into two groups according to the HRT treated period: short-term (<2 years of treatment, n = 52) and long-term ( 12 years, n = 63) HRT groups. The third group consisted an age-matched women (n = 73), who were never treated with HRT (non-HRT group) as a control. Results: Each group was divided into three subgroups according to age: less than or equal to49 years, 50-59 years and 60 years or older. IMT in patients of age greater than or equal to60 years in the non-HRT group was 0.607 +/- 0.064 mm and was significantly higher compared with that in the other two age subgroups of non-HRT patients (less than or equal to49 years: 0.495 +/- 0.051 mm; 50-59 years: 0.505 +/- 0.068 mm) (P < 0.05). In the short-term HRT group, IMT of greater than or equal to60-year-old-subjects (0.588 +/- 0.074 mm) was also significantly higher compared with that in the other two age subgroups (less than or equal to49 years: 0.480 +/- 0.034 mm; 50-59 years: 0.511 +/- 0.062 mm). However, in the long-term HRT group, IMT was not significantly different among the three age subgroups. There was a significant relationship between IMT and age in non-HRT (r = 0.594, P < 0.0001) and short-term HRT (r = 0.542, P < 0.001) groups, but no significant relationship was observed in the long-term HRT (r = 0.195, P = 0.1266) group. Conclusions: In long-term HRT, more than 2 years may delay the age-related increase in IMT in healthy postmenopausal Japanese women. (C) 2004 Elsevier Ireland Ltd. All rights reserved.