(Townsend and Nanchahal, 2005). And while the women in some countries, such as Japan, did receive HT at a much lower rate than those in the United States, there clearly were a number of countries with both extensive HT usage and a rapid growth in female life expectancy during the crucial 1980–2005 period (Goldman, 2010b).
The cross-country comparisons are not definitive because of various issues with the data, as well as the fact that HT is administered differently in different countries—orally versus via a transdermal patch or gel. Some Europeans are much more likely to use the latter alternatives. For example, estimates are that 70–80 percent of women in France use these methods (Canonico et al., 2007; Ringa et al., 2005; Varas-Lorenzo et al., 1998). The recent literature suggests that orally administered estrogens are more likely to result in cardiovascular risk (e.g., elevated C-reactive protein [CRP] levels or an increase in triglycerides) than nonorally administered estrogens (L’Hermite et al., 2008; Vrablik et al., 2008). Evidence also suggests that orally but not transdermally administered HT is related to a higher risk of thrombolytic events in postmenopausal women (Scarabin et al., 2003). These findings open up the possibility that HT could have had more negative health consequences in the United States than in other countries, but the evidence is not strong enough to draw any firm conclusions (Goldman, 2010b).
Still, Goldman concludes that there is little evidence supporting the hypothesis that HT played a part in the divergence of life expectancy trends among high-income countries. She bases her conclusions on three factors. First, the data indicate that HT does not appear to increase all-cause mortality risk. Second, when HT is timed as it typically is—that is, when it is begun near the onset of menopause—it does not appear to increase the risk of heart disease and may actually decrease the risk for some women. And third, HT does not appear to have been any more common among U.S. women than among women in several other countries where life expectancy continued to increase steadily throughout the second half of the 20th century (Goldman, 2010b).