Chlamydia pneumoniae seropositivity and cardiovascular risk factors: The InCHIANTI Study

J Am Geriatr Soc. 2004 Oct;52(10):1626-31. doi: 10.1111/j.1532-5415.2004.52453.x.

Abstract

Objectives: To assess the prevalence of Chlamydia pneumoniae (CP) seropositivity and test the hypothesis that CP infection (CPI) is associated with cardiovascular (CV) risk factors and levels of inflammatory biomarkers.

Design: Cross-sectional survey.

Setting: Representative sample of the residents of Greve in Chianti and Bagno a Ripoli, two small towns located in the Chianti geographic area (Tuscany, Italy).

Participants: A total of 1,304 (age-range: 20-103, 79% aged> or =65) participants of the InCHIANTI study.

Measurements: CP seropositivity was assessed using immunofluorescence. Previous CPI was defined as immunoglobulin (Ig) G > or =1/16 and <1/256, and recent CPI was defined as IgG > or =1/512 or IgM > or =1/16. Inflammatory markers included interleukin (IL)-6, soluble IL-6 receptor (sIL-6r), tumor necrosis factor-alpha (TNF-alpha), IL-1beta, IL-1 receptor antagonist (IL-1ra), iron, ferritin, and C-reactive protein (CRP). CV risk factors included smoking, body mass index (BMI), lipid profile, and hypertension.

Results: The prevalence of CP seropositivity was 75%, increased with age, and was higher in men than in women (P<.01). CPI was not associated with IL-1beta, IL-1ra, iron, ferritin, CRP, BMI, lipids, and smoking. After adjusting for age and sex, previous or recent CPI was associated with higher TNF-alpha (P<.01), IL-6 (P<.03), sIL-6R (P<.01), and hypertension (P<.02). In additional age and sex-adjusted models, the associations between CPI and TNF-alpha, IL-6, sIL-6r, and hypertension appeared to be mutually independent.

Conclusion: CP seropositivity is highly prevalent in the older population and is a significant, independent correlate of hypertension and circulating levels of TNF-alpha, IL-6, and sIL-6r.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Biomarkers / blood
  • Cardiovascular Diseases / etiology
  • Chlamydia Infections / blood
  • Chlamydia Infections / epidemiology*
  • Chlamydophila pneumoniae / immunology*
  • Cross-Sectional Studies
  • Cytokines / blood*
  • Female
  • Humans
  • Hypertension / complications
  • Hypertension / epidemiology
  • Italy / epidemiology
  • Male
  • Middle Aged
  • Risk Factors
  • Seroepidemiologic Studies
  • Sex Distribution

Substances

  • Biomarkers
  • Cytokines