Hormonal contraceptive use and Staphylococcus aureus nasal and throat carriage in a Norwegian youth population

Abstract

Background Use of hormonal contraceptives has been associated with Staphylococcus aureus nasal carriage in adult women. However, the role of hormonal contraceptives in S . aureus colonization among adolescents and associations with progestin only contraceptives are unknown. Methods We obtained nasal and throat swab samples from 439 girls aged 17–21 years in the population-based Tromsø study Fit Futures, 2012–2013, Norway, with information on lifestyle, health and biomarkers. We used multivariable logistic regression to study the association between use of hormonal contraceptives and Staphylococcus aureus carriage while adjusting for potential confounding factors. Results Staphylococcus aureus nasal carriage prevalence were 34%, 42%, and 61% among progestin-only users, non-users, and progestin-estrogen combination contraceptive users, respectively (P<0.001). Use of combination contraceptives doubled the odds of nasal carriage (non-users reference; OR = 2.31, 95%CI = 1.43–3.74). The OR of nasal carriage was 0.29 among progestin-only users compared to combination contraceptives users (95% CI = 0.12–0.67). Discussion In this study, use of combination hormonal contraceptives was associated with higher risk of Staphylococcus aureus nasal carriage in adolescent girls. Experimental design studies are needed to establish the role of exogenous sex steroids in Staphylococcus aureus colonization in women.

Circulating sex-steroids and Staphylococcus aureus nasal carriage in a general female population

“…From the population-based sixth Tromsø study (2007–2008), we reported higher nasal carriage among men and sex-differences in the distribution of S. aureus spa types (genetic variance by S. aureus protein A (spa) typing) ( 9 ). Among 400 young women in the Tromsø study fit futures (2012–2013), where 50% used hormonal contraception, we found a positive dose-response relationship between oestrogen dose and S. aureus nasal carriage, and a negative association between exogenous progesterone alone and nasal carriage ( 17 ). To our knowledge, no epidemiological study has examined whether endogenous sex-hormone levels are associated with S. aureus nasal carriage among women.…”

“…Smaller studies among women have found a positive association of nasal S. aureus carriage with biomarkers of endogenous oestrogen level ( 15 ), as well as of nasal S. aureus carriage with exogenous oestrogen and progesterone (i.e. hormonal contraceptive combination preparations) ( 16 , 17 ). One small study among premenopausal women found higher prevalence of persistent throat carriage of S. aureus with increasing levels of free fraction testosterone ( 18 ).…”

Sex differences in incidence and mortality of bloodstream infections. Results from the population-based HUNT study in Norway

“…Previous studies indicate higher probability of nasal colonization in men which is a major risk factor for invasive S. aureus infections (37). Other studies show that circulating levels of testosterone and use of hormone contraceptives among females alter nasal colonization indicating that sex hormones affect the immune response to S. aureus (38,39). The substantially higher prevalence of S. aureus colonization in men is of particular interest, and preventive measures like eradication or temporary suppression could lower the risk of invasive infections (40), which is especially important in hospitalized patients.…”

Molecular characteristics and risk factor analysis of Staphylococcus aureus colonization put insight into CC1 colonization in three nursing homes in Shanghai

“…Although Stensen et al reported that men have higher S . aureus nasal carrier rates than women [ 50 ], female sex was an independent risk factor for S . aureus colonization in the present study.…”