The National Institutes of Health’s Office of Research on Women’s Health celebrated its twentieth anniversary in 2010 with a new strategic plan recognizing the study of the biologic basis of sex differences as a distinct scientific discipline. It has become clear that both sex chromosomes and sex hormones contribute to these differences. Indeed, it is recommended that the term sex difference be used for biologic processes that differ between males and females and the term gender difference be used for features related to social influences. The clinical discipline of women’s health emphasizes greater attention to patient education and involvement in disease prevention and medical decision-making and has become a model for patient-centered health care.
DISEASE RISK: REALITY AND PERCEPTION
The leading causes of death are the same in women and men: (1) heart disease, and (2) cancer (Table 6e-1; Fig. 6e-1). The leading cause of cancer death, lung cancer, is the same in both sexes. Breast cancer is the second leading cause of cancer death in women, but it causes about 60% fewer deaths than does lung cancer. Men are substantially more likely to die from suicide and accidents than are women.
Death rates per 100,000 population for 2007 by 5-year age groups in U.S. women. Note that the scale of the y axis is increased in the graph on the right compared with that on the left. Accidents and HIV/AIDS are the leading causes of death in young women 20–34 years of age. Accidents, breast cancer, and ischemic heart disease (IHD) are the leading causes of death in women 35–49 years of age. IHD becomes the leading cause of death in women beginning at age 50 years. In older women, IHD remains the leading cause of death, cerebrovascular disease becomes the second leading cause of death, and lung cancer is the leading cause of cancer-related deaths. At age 85 years and beyond, Alzheimer’s disease (AD) becomes the third leading cause of death. Ca, cancer; CLRD, chronic lower respiratory disease; DM, diabetes mellitus. (Data adapted from Centers for Disease Control and Prevention, http://www.cdc.gov/nchs/data/dvs/MortFinal2007_WorkTable210R.pdf.)
Women’s risk for many diseases increases at menopause, which occurs at a median age of 51.4 years. In the industrialized world, women spend one-third of their lives in the postmenopausal period. Estrogen levels fall abruptly at menopause, inducing a variety of physiologic and metabolic responses. Rates of cardiovascular disease (CVD) increase and bone density begins to decrease rapidly after menopause. In the United States, women live on average about 5 years longer than men, with a life expectancy at birth in 2011 of 81.1 years compared with 76.3 years in men. Elderly women outnumber elderly men, so that age-related conditions such as hypertension have a female preponderance. However, the difference in life expectancy between men ...