Publications

During the past several years much new evidence has accumulated regarding the molecular and biochemical mechanisms underlying cardiac responses to hypoxia and to ischemia/reperfusion injury. Studies have involved cell culture, and ex vivo and in vivo preparations. This review focuses on regulation of two transcription factors that are thought to be important in these processes, hypoxia-inducible factor1alpha (HIF-1alpha) and heat shock factor (HSF). Both of these molecules are expressed acutely and chronically in response to hypoxia and ischemia/reperfusion, and both have numerous targets that comprise part of integrated response to ischemic injury aimed at promoting cell survival. Emphasis is placed on new mechanisms of action that regulate HIF-1alpha, HSF, and heat shock proteins as key responses to hypoxia and ischemia, and possible approaches to therapy based on these data are discussed.

BACKGROUND

The recent publication of clinical trial results has led to a dramatic shift in the evidence about postmenopausal hormone therapy.

OBJECTIVE

To examine whether the publication of clinical trial results, specifically the Heart and Estrogen/progestin Replacement Study (HERS) in 1998 and the Women's Health Initiative (WHI) in 2002, has influenced the use of hormone therapy among postmenopausal women.

DESIGN

Observational cohort (1997 to 2003).

SETTING

San Francisco Mammography Registry, San Francisco, California.

PARTICIPANTS

Postmenopausal women between the ages of 50 and 74 years without a personal history of breast cancer who underwent mammography (151862 mammograms).

MEASUREMENTS

Self-reported current use of hormone therapy.

RESULTS

Among menopausal women who had mammography, it was estimated that 41% were currently using hormone therapy in 1997. Before the publication of HERS, the use of hormone therapy was increasing at a rate of 1% (95% CI, 0% to 2%) per quarter. After the publication of HERS, use decreased by 1% (CI, -3% to 0%) per quarter. In contrast, the publication of the WHI in 2002 was associated with a more substantial decline in the use of hormone therapy of 18% (CI, -21% to -16%) per quarter. Similar associations were observed for most subgroups of women, including women older than 65 years of age; women with a previous hysterectomy; and women who described their race or ethnicity as white, African American, Latina, Chinese, or Filipina.

CONCLUSIONS

The release of the HERS data was temporally associated with a modest decline in the use of hormone therapy. In contrast, the release of the principal findings from the WHI was associated with a more substantial decline in use by postmenopausal women. The reason for the differences in decline may relate to the fact that the WHI results were widely publicized or were more applicable to most postmenopausal women because the WHI study was performed in healthy women.