We analyzed early mortality after total hip arthroplasty (THA) in patients with inflammatory arthritis (IA), adjusting for medical comorbidities and socioeconomic background.
Data on 6690 patients with IA who underwent THA during 1992-2012 were extracted from the Swedish Hip Arthroplasty Register. Data on comorbidity, measured using the Charlson Comorbidity Index (CCI), and socioeconomic data were gathered from the Swedish National Inpatient Register and Statistics Sweden. The CCI was divided into low (0), moderate (1-2), and high (> 2). Cox proportional hazards models were fitted to calculate adjusted HR of early mortality, with 95% CI.
Twenty-five patients (0.4%) died within 0-90 days, giving a 90-day unadjusted survival rate of 99.6% (CI 99.5-99.8). Comorbidity was associated with an increased risk of death within 90 days postoperatively [high vs low CCI: adjusted HR 9.0 (CI 1.6-49.9)]. There was a trend toward lower risk of death during the period 1999-2005, although patients operated on during this period had more comorbidities than those operated on from 1992 to 1998. A large proportion of patients was re-admitted to hospital within 90 days after the index procedure (30.2%), but rarely for cardiovascular reasons.
Medical comorbidity and an age above 75 years are associated with a substantial increase in the risk of early death after THA in patients with IA. Awareness of potential risk factors may alert clinicians and thus improve perioperative care.