Obesity and Staphylococcus aureus Nasal Colonization among Women and Men in a General Population

Abstract

BackgroundObesity and diabetes mellitus (DM) have been linked to increased risk of infections, and Staphylococcus aureus nasal colonization is a major risk factor for developing infections with the microbe. We therefore sought to find whether body mass index (BMI) and waist circumference (WC) could be associated with S. aureus colonization independent of DM.Methodology S. aureus colonization was assessed by nasal swab cultures among 2,169 women and 1,709 men, aged 30–87 years, in the population-based Tromsø Staph and Skin Study in 2007–08. Height (cm), weight (kg), WC (cm), and glycated haemoglobin (HbA1c,%) were measured. Multivariable logistic regression analyses including information on DM, HbA1c, hormonal contraceptive use and other potential confounders were used.ResultsIn the female population, each 2.5 kg/m2 increase in BMI was associated with a 7% higher odds of S. aureus nasal colonization (P = 0.01). When comparing obese and lean women aged 30–43 years, we observed that BMI ≥32.5 versus <22.5 kg/m2 and WC ≥101 versus <80 cm was associated with a 2.60 and 2.12 times higher odds of S. aureus colonization, respectively (95% confidence intervals 1.35–4.98 and 1.17–3.85). Among men, high WC was also associated with S. aureus nasal colonization. The associations did not change significantly when the analysis was restricted to participants without signs of pre-diabetes (HbA1c <6.0%) among women and men, and to non-users of hormonal contraceptives among women.ConclusionOur results support that obesity is a possible determinant for S. aureus nasal colonization independent of DM, in particular for premenopausal women. The role of obesity at different ages and by sex should be addressed in future prospective studies of S. aureus colonization.

Human body morphology, prevalence of nasopharyngeal potential bacterial pathogens, and immunocompetence handicap principal

“…This result corroborates the finding obtained by Olsen et al (2013) for older men (aged 30-87). Furthermore, males who had a high frequency of respiratory infections also had higher BMI's than those with a low frequency of these diseases.…”

“…Since we did not study persistent pathogen carriage (it was tested only once and not repeated after some time), it is possible that some of our subjects were only intermittent carriers. Studies by Olsen et al (2013) who collected also a second nasal swab after a median time of 28 days, however, showed that only 3.9% of participants had results that differed from the first swab nasal test. It is then unlikely that our results with only one swab are unreliable.…”

“…It is well known that carriage is the result of an ongoing struggle between the virulence factor of the pathogen and the host immune response, but the determinants of the carrier state are still not fully understood. The most important factors associated with colonization include genetic background (van Belkum and Meeles, 2005;van Belkum et al, 2007), sex (Olsen et al, 2012;van Belkum and Meeles, 2005), obesity (Olsen et al, 2013), socioeconomic status (Quintero et al, 2011), or allergic respiratory diseases (Pastacaldi et al, 2011). Recent studies also suggest that the presence of hemoglobin in nasal secretions can promote S. aureus nasal colonization (Pynnonen et al, 2011).…”

A Humoral Immune Defect Distinguishes the Response to Staphylococcus aureus Infections in Mice with Obesity and Type 2 Diabetes from That in Mice with Type 1 Diabetes

“…Regardless of the mechanism, the susceptibility of mice with T2D to nasal colonization by S. aureus was increased. Clinical studies have indicated that both T2D and obesity increase the rate of S. aureus colonization in the nares (29,30). Thus, the T2D mouse simulates the human disease state.…”

The Role of Adipocytes in Tissue Regeneration and Stem Cell Niches

“…Relative to lean controls, obese women have a greater risk of S. aureus colonization (Olsen et al 2013), and obese patients have a greater risk of infection after surgical procedures. Obese psoriatic patients are more likely to develop severe psoriatic outbreaks that are difficult to treat.…”