The most common causes of death in both men and women are heart disease and cancer, with lung cancer the top cause of cancer death, despite common misperceptions that breast cancer is the most common cause of death in women. These misconceptions perpetuate inadequate attention to modifiable risk factors in women, such as dyslipidemia, hypertension, and cigarette smoking. Furthermore, since women in the Unites States live on average 5.1 years longer than men, the majority of the disease burden for many age-related disorders (e.g., hypertension, Alzheimer's disease) rests in women. For a discussion of the menopause transition and postmenopausal hormone therapy, see Chap. 186.
SEX DIFFERENCES IN HEALTH AND DISEASE
Alzheimer's disease (AD) affects approximately twice as many women as men, due to larger numbers of women surviving to older ages and to sex differences in brain size, structure, and functional organization (See also Chap. 194). Postmenopausal hormone therapy may worsen cognitive function and the development of AD.
Coronary heart disease (CHD) presents differently in women, who are usually 10–15 years older than men with CHD and are more likely to have comorbidities, such as hypertension, congestive heart failure, and diabetes (See also Chaps. 128, 129, and 130). Women more often have atypical symptoms, such as nausea, vomiting, indigestion, and upper back pain. Physicians are less likely to suspect heart disease in women with chest pain and are less likely to perform diagnostic and therapeutic cardiac procedures in women. The conventional risk factors for CHD are the same in both men and women, though women receive fewer interventions for modifiable risk factors than do men. The marked increase in CHD occurring after menopause or oophorectomy suggests that endogenous estrogens are cardioprotective. However, hormone replacement therapy in postmenopausal women was not shown to be cardioprotective in controlled trials such as the Women's Health Initiative and other randomized trials. Therapy with estrogen plus progestin therapy was associated with increased cardiovascular events. The discrepancy between endogenous and exogenous estrogen effects is poorly understood but may be related to deleterious effects of late re-exposure to estrogen after a period of estrogen deficiency.
The prevalence of type 2 diabetes mellitus (DM) is similar between men and women (See also Chap. 184). Polycystic ovary syndrome and gestational diabetes mellitus are both common conditions in premenopausal women that carry an increased risk for type 2 DM. Premenopausal women with DM have identical rates of CHD to those of males.
Hypertension, as an age-related disorder, is more common in women than in men after age 60 (See also Chap. 126). Antihypertensive drugs appear to be equally effective in women and men; however, women may experience more side effects.