Sexually transmitted infections in the elderly: A growing concern in geriatric care

Abstract

Sexually transmitted infections (STIs) among the elderly are an underrecognized yet growing public health concern. This review explores the epidemiological trends, risk factors, and healthcare barriers contributing to STI burden in the elderly population. Factors such as physiological changes, low condom use, limited sexual health education, and under-recognition by healthcare providers heighten vulnerability in this group. Stigma and discomfort around sexual health discussions further impede prevention and timely diagnosis. The review also examines implications of immunosenescence, polypharmacy, and comorbidities on STI susceptibility and outcomes. Older adults are often overlooked in public health interventions for such infections. Hence, addressing this gap requires age-inclusive sexual health policies, tailored screening guidelines, and greater awareness among clinicians and the public.

Introduction

Sexually transmitted infections (STIs) are an important component of public health. However, the major focus while dealing with sexual health and STIs is on young sexually active adults. STIs among the older population generally remain a neglected area, due to the general belief that older people are not sexually active, and thereby are at a reduced risk of acquiring such infections. The definition of old age or the elderly population is arbitrary. Some consider individuals over 60 years old as elderly, while others set the cutoff at 55 or 65 years. In this narrative review, we have included studies that use the terms “old” or “elderly,” regardless of a specific age cutoff. Globally, there has been an increase in the proportion of the population above 60 years of age, which is primarily due to the better quality of healthcare services and ever-improving life expectancy. Asia and Europe are home to some of the world’s oldest populations aged above 65 years, the list being topped by Japan (28%) and Italy (23%).[1] In India, the census in 2011 revealed that 8% of its population is above 60 years of age, which is expected to increase in the coming years.[2]

Globally, there has been increasing evidence of the rise in rates of STIs among the older population.[3] Multiple factors, including continued sexual activity, though at low levels, reduced stigma and embarrassment, changing sexual norms, and extramarital relations primarily due to death or physical state of the partner, have been implicated as potential reasons placing older people at risk of STIs. This review article aims to provide current data on the incidence and prevalence of STIs in older people and the possible reasons behind the same.

Changing Sexual Behavior among Older Population

It is a common societal belief that older people do not have sexual desires and are not sexually active, thereby they cannot be at increased risk of STIs. However, research has demonstrated that even though sexual activity declines with age, older adults continue to be sexually active.[4] Studies have shown that older people continue to harbor sexual desires and interests and enjoy active sexual life.[5,6] Recent US research reveals that even though sexual activity decreases with age, a significant portion of older adults still remain sexually active. Around 73% of those aged 57–64, 53% of those aged 65–74, and 26% of those aged 75–85 reported being sexually active, challenging stereotypes about age and sexuality.[7] A similar study in England revealed that 86% of men and 60% of women aged 60–69 years were sexually active, as did 59% of men and 34% of women aged 70–79 years, and 31% of men and 14% of women aged 80 years or older.[8] The frequency of sex among sexually active adults between 75 and 85 years of age was two to three times per month in 54% and one or more times per week in 23%.[7] Kalra et al. reported that among 60 older individuals, 72% below 60 years and 57% above 60 years were sexually active. Importantly, significant sexual desire and function were present even after 60 years of age.[9] Furthermore, older sexually active people are less likely to use protective measures such as condoms when compared to their younger counterparts, putting them at increased risk of acquiring STIs.[10] A study by Amin assessed the association between social capital, i.e., the advantages a person can access through personal connections or social networks and sexual risk behavior among adults aged 55 years or older. Of the 547 participants, 87% reported not using barrier protection such as condoms during their last exposure and 15% reported high-risk behavior including casual sex, paid sex, male having sex with males (MSM), and drug use. Greater social capital was associated with an increased likelihood of HIV/other STI risk behaviors in the participants.[11] This data also suggests that despite the likely social embarrassment, physicians should inquire regarding sexual history in older patients with suspected STIs.

Trends of Sexually Transmitted Infections among Elderly [Table 1]

Table 1.

Studies describing the frequency of sexually transmitted infections among the geriatric population

Study	Study area	Demographic details	Frequency of various STIs
Fu et al., 1990-2019[12]	Global data	Older adults aged 60–89 years	77,327 new cases of HIV (age-standardized incidence rate 7.6 per 100,000 population) 26,414,267 new cases of other STIs (age-standardized incidence rate 2607.1 per 100,000 population)
Camacho et al., 2019[13]	England	Older adults aged ≥45 years	37,692 new STI diagnoses (Gonorrhea, Chlamydia, herpes, syphilis, warts, and HIV)
Relhan et al.[14] 2013–2018	India	Older adults aged ≥60 years	123 new STI cases in patients more than 60 years of age Vaginal discharge (25%) Candidal balanoposthitis (19.5%) Genital herpes (16.2%) Genital warts (16.2%) Genital scabies (6.5%) Genital molluscum (1.6%) Gonococcal urethritis (0.8%) Late latent syphilis (0.8%)
Tuddenham et al.[15] 2005–2010	Baltimore	Older adults aged ≥50 years	Total number of patients above the age of 50 years in STD clinic: 4461 Late syphilis (7.5%) Trichomoniasis (21.5%) HIV (3%)
Choe et al., 2009[16]	Korea	Older adults aged ≥60 years	Total number of patients above the age of 60 years who were screened: 1804 Syphilis (4/1804=0.222%) Chlamydia (14/1804=0.776%)

STIs: Sexually transmitted infections

HIV

Sexually active older adults are predisposed to acquiring HIV due to age-related weakening of the immune system, underlying health issues, and low use of barrier devices. Increased prevalence of HIV infection has been reported among the older population in certain areas of the world. The US Centers for Disease Control and Prevention reported that persons above 50 years contributed to 17% of new HIV diagnoses in the USA in 2016.[17] Global data from 2019 estimated 77,327 new cases of HIV among older adults globally, with an age-standardized incidence rate of 7.6 per 100,000 population.[12] Interestingly, the incidence rate had decreased by an average of 2.02% per year from 1990 to 2019. Contrary to the global decline, regions including Eastern Europe, Central Asia, and Asia-Pacific have demonstrated an increase in the incidence of HIV among the elderly.[12] England reported 850 new HIV cases among people aged more than 50 years in 2019. This was a decrease from 1051 new cases in 2014. In the period from 2014 to 2019, 72% of 5336 new cases in older people were males.[13] Mathematical model analysis by Kumar et al. has demonstrated that the mean age of HIV-infected people in India will increase from 38.4 years in 2005 to 45.5 years in 2025. The authors have also predicted that the proportion of HIV-infected people aged above 50 years will increase from 19% in 2005 to 37% in 2025.[18]

A comparison study with younger HIV-infected populations has shown that older individuals are more likely to be males, have greater acceptance of antiretroviral treatment, and have higher rates of HIV RNA <50 copies/mL.[19] Similarly, among HIV-infected MSM, older patients are more likely to use antiretroviral therapy, be aware of their infection, and be virally suppressed.[20]

The stigma and impact on quality of life in older adults with HIV is majorly like younger affected persons. Although the experience of stigma appears to reduce with age, however, in older adults, the fear of stigma and social rejection may lead to social isolation.[21,22] As mentioned earlier, older adults are more likely to comply with treatment, with studies demonstrating three times greater adherence as compared to younger adults.[23] The potential areas of concern with older HIV-infected include the weakened immune system, differential response to antiretroviral treatment, comorbidities, polypharmacy, and drug interactions, higher risk of opportunistic infections and neurocognitive defects, and functional disability, thereby at times requiring special attention in management.[24]

Syphilis

In the past decade, there has been a global increase in the prevalence of syphilis, including syphilis among the older population.[25] A systematic review by Htet et al., studying the prevalence of syphilis in adults 45 years and older in the US, showed prevalence ranging from 0% to 18% and incidence estimates ranging from 0.2 to 2.6 cases per 100 person-years.[26] Surveillance data from South China showed 242,115 new cases in older people from 2004 to 19, with a mean notification rate of 64.1 per 100,000 population.[27] As compared with young adults, older patients were more likely to be males, had unknown source of infection, and presented in late stages. The prevalence of syphilis seropositivity and active infection has also been shown to increase significantly with age, as demonstrated in a study from blood donors in South China.[28] The data on syphilis among the elderly in India are, however, lacking.

Primary chancre can be seen in elderly patients; however, it is less common than in younger adults [Figure 1]. Ocular involvement has been reported in a series of 4 old adults with secondary syphilis by Maves et al.[29] However, syphilis among the elderly is more likely to present as late latent or tertiary syphilis, as compared to young patients. Interestingly, seropositivity for syphilis has been demonstrated, though in a small subset of older adults presenting with unexplained neurological symptoms including stroke, cognitive decline, and neuropathy, necessitating testing in these patients.[30,31]

Figure 1.

Primary chancre on the penis in an elderly male

Anogenital warts

Anogenital warts caused by human papillomavirus (HPV) are one of the most common viral STIs worldwide. In a review by Poynten et al., it was demonstrated that, during the period between 2002 and 2010, there was an increase in rates of the first episode of anogenital warts in patients aged 15–64 and above 65 years in both genders.[32] Anogenital warts are a common diagnosis among older patients with STIs, as reflected in data from England in 2019.[13] Increase in rates of anogenital warts by 9% has been reported in females aged 45 years and older from 2002 to 2006.[33] Genital warts constituted 16.2% of cases among STIs in the elderly in an Indian study by Relhan and colleagues.[14] Data on the clinical types of anogenital warts and the response to treatment are, however, lacking in literature. Genital warts of varying morphologies can be seen in elderly patients [Figure 2a-d].

Figure 2.

(a) Multiple verrucous fleshy genital warts on the prepuce in an elderly male (b) Multiple flat-topped pigmented genital warts over the groin, scrotum, and pubic area in an elderly male (c) Multiple elevated papules of Bowenoid papulosis near the groin fold in an elderly male (d) Multiple verrucous pigmented genital warts on labia majora of an elderly female

HPV infection among the elderly gains further importance from the fact that it predisposes the affected to develop squamous cell carcinoma of the genitalia. HPV infection has been linked to 30%–50% of cases of penile cancer among elderly males.[34] With the widespread implementation of the HPV vaccine in persons aged 9–26 years, a decrease in HPV infection has occurred in this population. Long-term seroprotection has been demonstrated for various HPV vaccines, ranging from 4 to 12 years.[35] Booster doses have also demonstrated increased antibody titers in persons who had previously received the conventional vaccine doses.[36] However, further studies are required in the elderly population to assess its usefulness in this population.

Genital herpes

Genital herpes is a common STI presenting in older people, especially among females. In a study by Xu et al., the most common STI in elderly females above 50 years was genital herpes.[37] Vulvar ulcerations [Figure 3a], pain, and dysuria due to herpes can be mistaken for atrophic vaginitis in postmenopausal females. Eder described the occurrence and characteristics of genital herpes in an aging female population.[38] It can also present with penile erosions [Figure 3b]. Herpes simplex virus 2 (HSV-2) was implicated in 91.5% of cases. More than half (61%) experienced recurrences of which 48% had 1–6 recurrences and 11% had more than 7 recurrences per year, necessitating the use of suppressive antiviral therapy. Age-specific HSV-2 seroprevalence has been found higher in women as compared to men in studies from various parts of the world.[39] Furthermore, a study by Wang et al. showed that HSV-2 antibody level was an independent predictor of 5-year mortality in aged female patients, which is explained by the higher cardiovascular morbidity.[40] In the Indian context, herpes genitalis constituted 16.2% of STIs among the elderly population in a retrospective study.[14]

Figure 3.

(a) Multiple polycyclic erosions over the labia majora and posterior fourchette of an elderly female living with HIV. (b) Multiple polycyclic erosions over the glans penis and prepuce suggestive of genital herpes in an elderly male

Bacterial sexually transmitted infections

Bacterial STIs including gonorrhea and chlamydia infections can also occur in the elderly population. The prevalence of gonorrhea and chlamydia in older adults in the US ranged from 0% to 15%, based on various studies reported from 1993 to 2019.[26] The reported prevalence of gonorrhea is high, especially among the older MSM population. The prevalence of urethral, pharyngeal, and rectal gonorrhea was 15%, 1.1%, and 4.6% in the 45–54 age group MSM, respectively, in England.[41] Similarly, the prevalence of pharyngeal and rectal gonorrhea was 2.2% and 2.4% in MSM aged 50 years and above in a study from the US.[42] However, younger men were more likely to be diagnosed with gonorrhea and chlamydia when compared to older men in a study from Baltimore.[15] The prevalence of urethral chlamydia is also higher among the older MSM population, as shown in a study from Boston. Rates of urethral chlamydia were 5.9% among males aged 45–54 years and 6.7% among males aged more than 55 years.[41] Among MSM, the prevalence of rectal and pharyngeal chlamydia was 3.8% and 0.9%, respectively.[42] There were 17,112 new cases of gonorrhea and chlamydia in older adults from England in 2019.[13] In a study by Wilkinson et al., 4.2% positive cases for gonorrhea and chlamydia were seen among 1,232,173 tests performed in the veteran population.[43] Veterans with a history of combat and those married had a lesser chance of testing positive when compared to divorced veterans.

Trichomonas

Trichomonas caused by Trichomonas vaginalis is estimated to be the most common nonviral STI in the US. Estimates of trichomonas infections among adults aged more than 45 years varied from 0.2% and 21.4% in a review of 12 studies from the US.[44] The maximum prevalence was reported among women aged more than 50 years in an STI clinic from Baltimore.[15] A prevalence of 14.6% and 14.7% has been reported among patients between 45 and 49 years and more than 50 years, respectively, with a higher prevalence among females.[45] In another study from Iran, 34% (17 out of 50) of cases with positive trichomonas culture were seen in patients (6 males and 11 females) above 50 years of age.[46] Association between drug abuse and trichomonas infections among mid-older adults was reported by Hearn et al.[47] Importantly, trichomonas infection was a major etiological agent in chronic prostatitis among elderly males.[48] T. vaginalis was cultured in 8.9% of ejaculate samples, with a significant increase seen in patients in the seventh decade.

Factors Contributing to Sexually Transmitted Infections in Elderly

Various factors considered to be contributing to increased STI acquisition among the older population are explained in Figure 4. The possible factors include increased life expectancy, changing sexual behaviors, decreased condom use, new partners, increased divorce rates, lack of awareness regarding STIs, decreased healthcare-seeking behavior owing to stigma and embarrassment, and use of medications to increase libido and improve erectile dysfunction.[32]

Figure 4.

Various factors associated with increased risk of sexually transmitted infections among the geriatric population

As mentioned above, the high-risk sexual behavior among the elderly predisposes them to acquiring STIs. Studies from various parts of the world have shown that the elderly with STIs are more likely to have multiple partners, high rates of contact with commercial sex workers, high rates of MSM, and low use of condoms during intercourse.[49,50] In a study from Australia to assess the knowledge about STIs in 1652 elderly respondents, the knowledge regarding protection offered by condoms and potential modes of transmission of STIs was poor.[51] Increasing STIs among the elderly highlights the need for policies and education programs to increase awareness regarding STIs in this population.

Regarding the association of STIs in persons using drugs for erectile dysfunction, a study by Jena et al. showed that users of drugs have higher rates of STIs both before and 1 year after initiation of treatment. The authors suggested that counseling regarding safe sex practices and screening for STIs in persons using drugs for erectile dysfunction would be beneficial.[52]

In addition, older people are biologically more susceptible to STIs as compared to younger counterparts owing to impaired immunity and comorbidities. Lower estrogen levels and decreased vaginal mucosal barrier may predispose postmenopausal females to bacterial vaginosis and micro abrasions in mucosa acting as a portal of entry for pathogens causing STIs.[32]

Screening and Management

STIs in the elderly can be new infections or infections acquired long back which were not adequately treated. In addition, genital symptoms in the elderly may be nonspecific and could be attributed to non-STIs. For example, genital herpes can be mistaken for plasma cell balanitis/vulvitis, and infectious causes of vaginal and cervical discharge may be mistaken for gynecological causes such as atrophic vaginitis. Proper elucidation of sexual history becomes pertinent in such cases. Diagnostic tests for STIs in this population are like those employed in younger counterparts. Management strategies are also similar; however, special attention needs to be paid to comorbidities, polypharmacy, and possible drug interactions. In addition, education regarding safe sexual practices and condom use becomes imperative to prevent further STIs. There is also a need to provide additional focus to this neglected population in STI clinics and programs to reduce stigma, raise awareness, and improve access to sexual health care.

Conclusion

Addressing STIs among older populations is imperative but often neglected. With increasing life expectancy, STIs in the elderly are common. There is a lack of epidemiological data regarding STIs in the elderly, especially from the Asia-Pacific and African countries. Large-scale community trials with etiological diagnosis and assessment of sexual behavior are required to fill the lacuna. Older individuals with STIs possibly face double jeopardy: societal silence and neglect by healthcare providers, thereby necessitating recognition of the sexual needs of the elderly and their vulnerability to STIs. Healthcare providers need to provide special attention to elders with STIs to ensure proper diagnosis and optimum management.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.