Long-term effects of the Women’s Health Initiative in the USA
16 July, 2012:
To study long-term prescriptions of hormone therapy (HT) in postmenopausal women, during a decade after the Women's Health Initiative (WHI), Steinkellner and colleagues [1] used a national pharmacy database from 2000 to 2009. Women who were 50 years and older at the start of the calendar year with continuous pharmacy benefits during the entire 12-month period were included in the study population for that year. The yearly study population varied from a low of 3,579,838 in 2000 to a high of 9,712,325 in 2009. The prevalence of HT use in each year's study population dropped from 21.6% in the year 2000 to 8.8% in the year 2009. The sharpest decline occurred between 2001 and 2003 and then it remained relatively stable. Analysis of different age groups showed a maximum fall in the decade 65–74 years old.
In the year 2000, oral HT accounted for 19% of this 21.6% and then it went down to a prevalence of 4.8% in 2009. Transdermal estrogen, not very popular in the US, remained stable throughout this period of time – around 4%, and vaginal formulations increased from an annual incidence of 0.9% in the year 2000 to 1.7% in 2009.
High and standard doses showed a prevalence of 16.6% in 2000 and then declined very fast in 2003 and continued to run low till 2009 with a share of 2.4%. Low-dose preparations remained constant in the range of 2.3–2.5% during the study period.
At the beginning of this survey, the prevalence of women prescribed by GP/IM/FP (Family Practice/Internal Medicine/General Practice) was 9.9% and gynecologists contributed another 8.8%. At the end of the decade, the gynecologists became the main prescribers of HT, with a prevalence of 5.3%, whereas GP/IM/FP accounted for only 2.9%.
Comment
This review suggests a lasting impact of the WHI results on prescription patterns. The review's strengths include a large sample size and the inclusion of all US regions, although it studied only insured women using their pharmacy benefit.
I would like to stress the following points. First, the study showed that, after a sharp decline in 2002–2003, the annual incidence of new women in their fifties who were receiving HT remained stable. Second, low and very low doses seemed to be actually preferred, as well as the non-oral route of administration, avoiding the hepatic first pass. Third, the leading prescribers turned out to be the gynecologists and not the family physicians or the internists, focusing on the treatment of menopausal symptoms and its consequences rather than the prevention of cardiovascular diseases. This is a shift in paradigm that has never had a full exposure in Argentina. Progestogen is not mentioned in the paper, but could be of medical interest by changing from medroxyprogesterone acetate to micronized progesterone, to complete a brighter panorama for HT after the lasting shock of the WHI study. Now, we need long-term safety studies of these formulations for the sake of postmenopausal women, their quality of life and good health.
Roberto Ítalo Tozzini
Honorary Professor, National University of Rosario, Argentina
References
1. Steinkellner AR, Denison SE, Eldridge SL, Lenzi LL, Chen W, Bowlin SJ. A decade of postmenopausal hormone therapy prescribing in the United States: long-term effects of the Women's Health Initiative. Menopause 2012;19:616-21.
http://www.ncbi.nlm.nih.gov/pubmed/22648302
Content updated 16 July 2012