BACKGROUND: Patients with very low weight treated with percutaneous coronary intervention have a greater risk of complications during hospitalization. So far, there have been no studies to evaluate the long-term effect of low weight after coronary angioplasty in the Brazilian population. METHODS: A total of 3,687 patients were divided into two groups according to their body mass index (BMI), calculated by dividing the weight in kilograms by the height in metres squared: low-weight group (BMI < 20 kg/m²; 125 patients), and non-low-weight group (BMI > 20 kg/m²; 3,562 patients). The in-hospital mortality was evaluated prospectively during first admission. After discharge, death occurrence was assessed by reviewing hospital records and through telephone contact. RESULTS: Patients with BMI < 20 kg/m² presented weight, height, and BMI averages of 49.4 ± 7.1 kg, 1.62 ± 0.10 m, and 18.7 ± 1.1 kg/m², respectively. The weight, height and BMI of patients with BMI > 20 kg/m² was 74.4 ± 13.8 kg, 1.64 ± 0.09 m, and 27.3 ± 4.3 kg/m², respectively (p < 0.01 for all characteristics). Patients from the low-weight group showed significantly higher mortality than patients with BMI > 20 kg/m² 2.5 years after angioplasty (19.4% vs. 6.9%, respectively; hazard ratio [HR]: 2.51; 95% confidence interval [95% CI]: 1.61-3.91; p < 0.01). After multivariate adjustment for other risk factors, the presence of BMI < 20 kg/m² persisted as an independent factor associated to increased mortality (HR: 2.04; 95% CI: 1.28-3.25; p < 0.01). CONCLUSIONS: The very low ponderal weight, indicated by a body mass index < 20 kg/m², is an independent risk factor for early and late death in the first 2.5 years after percutaneous intervention. Due to its easy identification, very low weight can be widely used as a predictive tool for patients routinely treated with angioplasty.
Angioplasty, transluminal, percutaneous coronary; Body mass index; Prognosis
