Recent data from the Centers for Disease Control and Prevention reveals a concerning trend – diagnoses for sexually transmitted infections (STIs) are on the rise among older adults. The numbers have increased significantly for individuals over the age of 65, with cases of chlamydia, gonorrhea, and syphilis seeing a three-, five-, and sevenfold increase respectively from 2010 to 2023. Moreover, women over 50 are now at a greater risk for HIV compared to younger women. But what is causing this spike in STIs among the older population?
Several factors may help explain the prevalence of STIs in older adults. Limited understanding of STIs in this age group, infrequent condom use, and the availability of medications such as Viagra and Cialis for erectile dysfunction, and estrogen creams for vaginal dryness that can increase sexual activity, are contributing factors. Additionally, older adults may be more hesitant to discuss their sexual history with their partners and healthcare providers, leading to misconceptions about their sexual activity.
As an infectious disease scientist, I have explored the biological reasons behind the increased vulnerability of postmenopausal women to STIs. Menopause, defined as 12 consecutive months without menstrual periods and occurring on average between ages 45 and 55 in the U.S., results in a decline in estrogen production from the ovaries. This hormonal change can lead to vaginal dryness, irritation, and other symptoms of genitourinary syndrome of menopause (GSM), affecting nearly half of postmenopausal women.
Research has shown that menopause not only affects vaginal lubrication and tissue elasticity but also compromises the structural integrity of the vaginal lining. Proteins like desmoglein-1 (DSG1) and desmocollin-1 (DSC1) play a crucial role in maintaining the vaginal barrier and reducing the risk of infections. Comparing the levels of DSG1 and DSC1 in postmenopausal and premenopausal women, significant differences were observed, indicating a weakening of the vaginal lining post-menopause.
Animal Studies
Animal studies involving mice without ovaries, mimicking the estrogen decline seen in postmenopausal women, further confirmed the link between menopause and increased susceptibility to infections like herpes simplex virus type 2 (HSV-2) and chlamydia. However, the application of estrogen cream restored the integrity of the vaginal lining in mice without ovaries, protecting them from HSV-2 infection.
Understanding both the behavioral and biological risk factors contributing to STI susceptibility in older adults is crucial for healthcare providers and public health officials. By addressing the loss of integrity in the vaginal lining post-menopause, interventions like estrogen-containing compounds could potentially reduce the risk of STIs in older adults. In the meantime, consistent counseling on safe sex practices and routine STI screening by healthcare providers can help mitigate the rising rates of STIs among older individuals.
Leave a Reply