Association of hernia with subsequent aortic aneurysm in geriatric patients

Abstract Objective Although inguinal hernia and aortic aneurysm share similar pathogenic mechanisms of collagen and elastin destruction, their clinical association in geriatric patients is inconclusive. We assessed the association between hernia and the subsequent occurrence of aortic aneurysm in geriatric patients. Methods Adult patients with hernias between 2000 and 2012 were identified from a longitudinal claims database of one million beneficiaries from Taiwan’s National Health Insurance program, and a control group of patients without hernia were matched by propensity score in a ratio of 1:3. Patients previously diagnosed with aortic aneurysms or connective tissue diseases were excluded. Follow-up ended on December 31, 2013. The incidence rate of aortic aneurysm was compared between patients with hernia and those without. Cox proportional hazards models were used to estimate relative hazards. Results After propensity score matching, there were 16,933 hernia (aged 20-64: 10,326; ≥65: 6,607) and 50,799 non-hernia patients (aged 20-64: 30,978; ≥65: 19,821). Hernia patients had a higher incidence rate and hazard ratio of aortic aneurysm than did non-hernia patients [6.4 vs. 4.8 /10,000 person-year (PY); adjusted sub-distribution hazard ratio [sdHR]:1.34; 95% CI: 1.02-1.76; p = 0.03], especially for those aged ≥65 (15.6 vs. 10.4 /10,000 py; adjusted sdHR: 1.44; 95% CI: 1.07-1.94; p = 0.01) In addition, geriatric patients with hernia were associated with a marginally higher risk of thoracic (adjusted sdHR: 1.66; 95% CI: 0.96-2.86) and abdominal (adjusted sdHR, 1.36; 95% CI: 0.96-1.94) aortic aneurysm rupture. Conclusion Geriatric patients with hernia were associated with a higher incidence of aortic aneurysm than were those without.