Current and Past Obesity in Japanese Patients with Critical Limb Ischemia Undergoing Revascularization

Aim: Recent studies suggested that past history of obesity or maximum body mass index (BMI) in the past was a strong prognostic predictor in a general population. The current study aimed to survey the distribution of current and maximum BMIs and to investigate their prognostic impact in patients with critical limb ischemia (CLI), whose prognosis was poor even after revascularization. Methods: We analyzed a database of a prospective, multicenter registry in Japan, including 499 CLI patients undergoing revascularization. Their current and maximum BMIs were surveyed at registration. The distribution and the impact on the prognosis were explored. Results: The estimated means (95% confidence intervals) of current and maximum BMIs were respectively 22.0 (21.7 to 22.3) and 25.3 (24.8 to 25.8) kg/m(2); the difference was 3.3 (2.9 to 3.7) kg/m(2). The prevalence of current obesity (BMI ≥ 25 kg/m(2)) was 18% (15% to 22%), whereas 48% (43% to 53%) had ever been obese (maximum BMI ≥ 25 kg/m(2)). Past obesity was not rare even in currently lean subjects (BMI < 18.5 kg/m(2)), with the prevalence of 18% (7% to 29%). Current BMI, but not maximum BMI, was associated with the mortality risk; the adjusted hazard ratios per 5 kg/m(2) increase were 0.61 [0.46, 0.81] (P = 0.001) and 1.07 [0.87, 1.31] (P = 0.55), respectively. Conclusion: The prevalence of current obesity was as low as 18% (15% to 22%) in Japanese CLI patients undergoing revascularization, whereas about a half were formerly obese. Maximum BMI was not independently associated with the mortality risk in the population.