Effect of body mass index on 30- and 365-day complication and survival rates of transcatheter aortic valve implantation (from the FRench Aortic National CoreValve and Edwards 2 [FRANCE 2] registry)

Abstract

The "obesity paradox" that patients with high body mass index (BMI) have good prognoses remains controversial. This study aimed to assess the impact of BMI on clinical outcomes in patients who underwent transcatheter aortic valve implantation (TAVI). Data from the French national TAVI registry were collected for 3,072 patients who underwent TAVI from January 2010 to October 2011. The patients were categorized into 4 groups according to BMI (kg/m(2)): underweight (<18.5 kg/m(2)), normal weight (18.5 to 25 kg/m(2)), overweight (25 to 30 kg/m(2)), and obese (>30 kg/m(2)). Thereafter, clinical outcomes were compared among the 4 groups. The BMI distribution was 3.1% (n = 95), 44.1% (n = 1,355), 34.2% (n = 1,050), and 18.6% (n = 572). Although the 4 groups greatly differed in baseline clinical background, they had similar procedural success rates (95.8%, 97.1%, 97.3%, and 95.6%, p = 0.23). Major vascular complication was significantly associated with the underweight patients after adjusting for the other potential confounders (odds ratio 2.33, 95% confidence interval 1.17 to 4.46, p = 0.016). The cumulative postoperative survival rates were increasing across the 4 groups at 30 days (83.2%, 88.9%, 91.6%, and 93.0%, p = 0.003) and 1 year (67.9%, 73.6%, 77.4%, and 80.3%, p = 0.006). In a multivariate Cox regression analysis, the overweight and obese patients were independently associated with superior cumulative survival rate at 1 year (hazard ratios 0.74 and 0.71, 95% confidence intervals 0.57 to 0.97 and 0.59 to 0.87, p = 0.050 and 0.029, respectively). In conclusion, major morbidity and 1-year mortality were less in overweight and obese patients than those classified as normal weight even in a TAVI cohort.