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ホルモン置換療法の開始,中止,継続的な使用に関連した乳房密度の変化
C M Rutter1, M T Mandelson, M B Laya
1Group Health Cooperative of Puget Sound, Center for Health Studies, 1730 Minor Ave, Suite 1600, Seattle, WA 98101, USA. rutter.c@ghc.org
JAMA
|February 15, 2001
まとめ
ホルモン置換療法 (HRT) の開始は乳房密度を高め,中止は乳房密度を低下させる. 乳腺密度のこれらの動的変化は,閉経後の女性のHRT使用と関連しています.
科学分野:
- 生殖内分泌学 生殖内分泌学
- 腫瘍学 腫瘍学
- 放射線学 放射線学
背景:
- ホルモン補充療法 (HRT) は,乳房の密度を増加させることが知られている.
- 乳房の密度の上昇は,マンモグラフィの感度低下と関連しています.
- HRTの中止と継続が乳房密度に及ぼす影響に関する体系的な研究は欠けている.
研究 の 目的:
- HRTの開始,中止,継続が乳房密度に与える影響を調査する.
- HRTを受ける閉経後の女性の乳房密度の変化を分析する.
- HRTと乳房密度の間のダイナミックな関係に関するデータを提供する.
主な方法:
- 5212人の閉経後の女性を対象とした観察コホート研究.
- 1996年から1998年の間にスクリーニング・マンモグラフィーから収集されたデータ.
- BI-RADSスケールを使用して評価された乳房密度,HRT使用者 (開始者,中止者,継続者) と非使用者を比較する.
主要な成果:
- HRTを開始すると,乳房の密度が著しく増加しました (RR, 2.57).
- HRTの中止は乳房密度の低下と関連していた (RR,1.81).
- HRTの継続的な使用は,増加した密度 (RR, 1.33) と持続的な高密度 (RR, 1.45) を示した.
結論:
- HRTに関連する乳房密度の変化は,動的である.
- HRTを開始すると,乳房の密度が増加します.
- HRTを中止すると,乳房の密度が低下します.
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