Venous thromboembolism: HRT increases the risk

Clinical bottom line (level 1b)

Postmenopausal women who took hormone replacement therapy compared with placebo were more likely to have a venous thromboembolism (NNH = 66 at 4 years) .

Grady et al: Annals of Internal Medicine 2000; 132 : 689-696

Expires November 2003

The study

Double-blinded ?concealed randomised trial with intention-to-treat
Setting: 20 clinical centres, USA

2763 patients (aged 44 to 79; mean 67, 100% female) postmenopausal with coronary disease (MI, CABG, percutaneous coronary revascularisation)

Excluded if

coronary event within 6 months of randomisation
used hormone therapy within 3 months of randomisation
history or baseline findings of venous thromboembolism, breast cancer, or endometrial cancer
uncontrolled hypertension, diabetes or other life-threatening diseases
hysterectomy

aged > 80

Control Group: (n = 1383, 1383 analysed): placebo
Experimental Group: (n = 1380, 1380 analysed): conjugated equine estrogens 0.625 mg plus medroxyprogesterone acetate 2.5 mg in one tablet daily

100% followed for 4.1 years

The evidence

Outcome	Time to outcome	CER	EER	RRR (95% CI)	ARR (95% CI)	NNH (95% CI)
documented PE or DVT	4 years	13 (0.94%)	34 (2.46%)	-160% (-390% to -39%)	-1.52% (-2.49% to -0.561%)	66 (40 to 180)
documented DVT	4 years	9 (0.65%)	25 (1.81%)	-180% (-490% to -30%)	-1.16% (-1.98% to -0.34%)	86 (50 to 300)

Comments

Patients were stratified according to clinical centre and randomised in blocks of four.

Citation

Grady D, Wenger NK, Herrington D, et al: postmenopausal hormone therapy increases risk for venous thromboembolic disease: the heart and estrogen/progestin replacement study (HERS). Annals of Internal Medicine 2000; 132 : 689-696

Search Terms: in ACP Journal Club
Contributor: Chris Ball, November 2001
Reviewer:

_{Clinical Question.}

_Patient	_{postmenopausal}
_{Intervention or Exposure}	_{hormone replacement therapy}
_Comparison	_placebo
_Outcome	_{venous thromboembolism}