Geriatric population is more vulnerable to septic arthritis (SA) because of the higher risk factors than the younger population. Due to delayed in diagnosis and treatment, the mortality rate was higher in the geriatric population.

A population-based cohort study was conducted by Chia-Jung Wu et al. to determine the long-term mortality risks in geriatric patients with SA as well as the mortality predictors. This study included all the geriatric participants (age ≥ 65 years) and excluded those who had SA before 1999 and categorised them into three groups young elderly (65–74 years), moderately elderly (75–84 years), and old elderly (≥ 85 years). The included subjects were assessed for various comorbidities that affect mortality. The participants were followed up until the end of 2011 to compare the all the risk factors caused mortality. After the regression analysis, it was found that Geriatric participants with SA had increased mortality than those without SA with Adjusted hazard ratio (AHR): 1.49, particularly the old elderly (≥ 85 years, AHR: 2.12) and males (AHR: 1.54). These results were affirmed after adjustment for diabetes, OA, gout, RA, renal disease, liver disease, cancer, systemic lupus erythematosus, alcoholism, and HIV infection. The increased mortality risk was observed to be the highest in first month with AHR: 3.93 and remained increased even after following up for 2–4 years (AHR: 1.30). After Cox proportional hazard regression analysis, SA, male sex, diabetes, renal disease, liver disease, cancer, and gout were independent predictors of mortality. There was no significant difference in the mortality for SA between upper limb affected and lower limb affected.

The results of this prospective cohort study showed that long-term mortality was significantly higher in the older geriatric population with SA than in those without SA. After diagnosis, the impact of mortality was highest in the first six months and lasted until 1–2 years.