Risk Factors for CRS Plus Asthma Differ Among Younger vs Older Patients

Risk factors as predictors of asthma prevalence among a cohort of patients living with chronic rhinosinusitis (CRS), as they related to age, were evaluated by clinical investigators from the College of Medicine at Korea University.

In this study that evaluated potential risk factors associated with comorbid chronic rhinosinusitis (CRS) and asthma prevalence, age-related differences were found, according to the study authors who published their findings in Ear, Nose & Throat Journal.

Patients were stratified by age (<60 years, >60 years) and disease state (healthy controls, has CRS, has CRS and asthma), with the investigators from the College of Medicine at Korea University using data on noninstitutionalized citizens—representing more than 26,000 samples— from the Korean National Health and Nutrition Examination Survey.

“CRS and asthma are interrelated in the concept of a unified airway,” the authors wrote. “So far, studies on the relationship between age and CRS with asthma have not been reported.”

They investigated potential influence from age, sex, alcohol consumption, smoking history, household income, residence, education level, occupation, and body mass index (BMI). The control group had the most participants (n = 24,054; mean [SD] age, 49.8 [16.32] years) and the CRS with asthma group, the fewest (n = 157; mean age, 55.2 [15.65] years). The CRS group comprised 2124 participants, with a mean age of 51.4 (16.55) years. A majority of patients in each group lived in an urban location (77.05%, controls; 75.10%, CRS; 70.06, CRS with asthma) and had no smoking history (79.19%, 75.24%, and 78.98%, respectively).

Overall results show that for patients older than 60 years, only BMI showed a potential association with asthma development in a crude analysis that compared the control group vs the CRS with asthma group and the CRS vs CRS with asthma groups:

  • Controls vs CRS: odds ratio (OR), 1.087 (95% CI, 1.002-1.179; P = .0443)
  • CRS vs CRS with asthma: OR, 1.104 (95% CI, 1.014-1.201; P = .0224)

Risks for both were close to equal in an adjusted analysis, at 8.8% and 10.4%, respectively.

Study participants who were younger had more potential risk factors, with analyses showing higher risks associated with lesser education, BMI, and total immunoglobulin E (TIgE) levels:

  • Controls vs CRS with asthma:
    • Education level:
      • 6-9 years: OR, 1.253 (95% CI, 0.585-2.684; P = .5621)
      • 9-12 years: OR, 0.403 (95% CI, 0.197-0.826; P = .0131)
      • More than 12 years: OR, 0.342 (95% CI, 0.16-0.732; P = .0057)
    • BMI: OR, 1.09 (95% CI, 1.023-1.162; P = .0082)
    • TIgE: OR, 5.582 (95% CI, 1.794-17.367; P = .003)
  • CRS vs CRS with asthma:
    • Education level:
      • 6-9 years: OR, 1.637 (95% CI, 0.733-3.656; P = .2297)
      • 9-12 years: OR, 0.487 (95% CI, 0.232-1.022; P = .0572)
      • More than 12 years: OR, 0.478 (95% CI, 0.218-1.05; P = .0659)
    • TIgE: OR, 4 (P = .0218)

Following adjusted analyses of the control vs CRS with asthma groups, a negative correlation was seen with education level, indicating that fewer years of education indicated a higher risk of developing CRS with asthma, and positive correlations with BMI and TIgE levels, indicating the same. When findings between the CRS and CRS with asthma groups were adjusted, education level again had a negative correlation and TIgE, a positive correlation.

A final analysis, this time of nasal endoscopic findings between the control and CRS-with-asthma groups, showed that among both age groups in this study, having pale mucosa, watery discharge, mucous/pus-like discharge, and middle meatus pus-like discharge had higher associated risks of developing asthma:

  • Younger than 60 years:
    • Pale mucosa: OR, 2.212 (95% CI, 1.212-4.035; P = .0097)
    • Watery discharge: OR, 3.616 (95% CI, 2.107-6.206; P < .001)
    • Mucous/pus-like discharge: OR, 4.777 (95% CI,2.571-8.879; P < .001)
    • Middle meatus pus-like discharge: OR, 6.767 (95% CI, 3.171-14.44; P < .001)
  • Older than 60 years:
    • Pale mucosa: OR, 1.453 (95% CI, 0.676-3.123; P = .3388)
    • Watery discharge: OR, 2.394 (95% CI, 1.113-5.152; P = .0255)
    • Mucous/pus-like discharge: OR, 6.72 (95% CI, 3.552-12.711; P < .001)
    • Middle meatus pus-like discharge: OR, 5.525 (95% CI, 2.544-11.997; P < .001)

“Although deeper longitudinal studies are necessary to clarify causality,” the authors concluded, “this national study provides several useful pointers for otorhinolaryngology clinicians to diagnose patients with CRS and asthma.”

Limitations on their findings’ generalizability include the study’s cross-sectional design, which prevented the authors from definitely determining the relationship between disease progression and risk factors of CRS with asthma, and lack of sensitization data on indoor allergens. A principal strength is that endoscopic diagnoses were made by specialists and using serum allergen results that “provided strong objective support for the results.”


Tai J, Jeong Y, Lee K, Park J, Han M, Kim TH. Analysis of age-related prevalence and risk factors of chronic rhinosinusitis and asthma. Ear Nose Throat J. Published online August 29, 2022. doi:10.1177/01455613221121022