TY - JOUR

T1 - The associations between socioeconomic status and risk of Staphylococcus aureus bacteremia and subsequent endocarditis - a Danish nationwide cohort study

AU - Oestergaard, Louise Bruun

AU - Schmiegelow, Michelle D.

AU - Bruun, Niels Eske

AU - Skov, Robert L.

AU - Petersen, Andreas

AU - Andersen, Paal Skytt

AU - Torp-Pedersen, Christian

PY - 2017/8/25

Y1 - 2017/8/25

N2 - Background: Staphylococcus aureus bacteremia (SAB) is the leading cause of infective endocarditis in several countries. Since socioeconomic status (SES) is known to influence the risk of infectious diseases in general, we aimed to investigate the association between SES and SAB, and risk of subsequent endocarditis in a nationwide adult population. Methods: All Danish residents were consecutively included at age≥30years during 1996-2010. We obtained information on SES (highest attained educational level), comorbidities, and microbiologically verified SAB by cross-linking nationwide registries. The incidence rate ratios (IRRs) of SAB and later endocarditis were investigated using Poisson regression models adjusted for sex, age and year (reference=highest SES). Results: Our study population comprised 3,394,936 individuals (median age=43.2years). Over a median follow-up of 15.9years, 13,181 individuals acquired SAB. SES was inversely associated with SAB acquisition, which declined with increasing age, e.g. in individuals with lowest SES, IRRs were 3.78 (95% confidence interval [CI]=2.89-4.95) in age 30-50years, 1.87 (CI=1.60-2.18) in age>50-70years and 1.31 (CI=1.11-1.54) in age>70years (interaction-p<0.0001). Adjustment for comorbidities attenuated the IRRs, but the pattern persisted. No association between SES and endocarditis risk among patients with SAB was observed. Conclusions: Decreasing SES was associated with an increased risk of SAB, particularly in younger adults. SES was not associated with risk of subsequent endocarditis.

AB - Background: Staphylococcus aureus bacteremia (SAB) is the leading cause of infective endocarditis in several countries. Since socioeconomic status (SES) is known to influence the risk of infectious diseases in general, we aimed to investigate the association between SES and SAB, and risk of subsequent endocarditis in a nationwide adult population. Methods: All Danish residents were consecutively included at age≥30years during 1996-2010. We obtained information on SES (highest attained educational level), comorbidities, and microbiologically verified SAB by cross-linking nationwide registries. The incidence rate ratios (IRRs) of SAB and later endocarditis were investigated using Poisson regression models adjusted for sex, age and year (reference=highest SES). Results: Our study population comprised 3,394,936 individuals (median age=43.2years). Over a median follow-up of 15.9years, 13,181 individuals acquired SAB. SES was inversely associated with SAB acquisition, which declined with increasing age, e.g. in individuals with lowest SES, IRRs were 3.78 (95% confidence interval [CI]=2.89-4.95) in age 30-50years, 1.87 (CI=1.60-2.18) in age>50-70years and 1.31 (CI=1.11-1.54) in age>70years (interaction-p<0.0001). Adjustment for comorbidities attenuated the IRRs, but the pattern persisted. No association between SES and endocarditis risk among patients with SAB was observed. Conclusions: Decreasing SES was associated with an increased risk of SAB, particularly in younger adults. SES was not associated with risk of subsequent endocarditis.

KW - Education

KW - Endocarditis

KW - Risk factors

KW - Social status

KW - Staphylococcus aureus

KW - Young adults

U2 - 10.1186/s12879-017-2691-3

DO - 10.1186/s12879-017-2691-3

M3 - Journal article

C2 - 28841914

AN - SCOPUS:85028309609

VL - 17

JO - B M C Infectious Diseases

JF - B M C Infectious Diseases

SN - 1471-2334

M1 - 589

ER -