Long-term follow-up of high-risk patients in the National Emphysema Treatment Trial.

Abstract

The National Emphysema Treatment Trial (NETT) was a randomized clinical trial designed to compare lung volume reduction surgery (LVRS) with maximal medical care for patients with severe emphysema. The trial was halted early for a subgroup of patients with severe lung disease. We report longer term follow-up for this high-risk subgroup. In a randomized clinical trial, patients with moderate to severe emphysema were assigned to LVRS plus maximal medical care or to maximal medical care alone and followed prospectively for vital status over 15 years. We focus on 140 high-risk patients. Quality of life data were available through 6 years of follow-up and were assessed using the University of California, San Diego Shortness of Breath Questionnaire and the Self-Administered Quality of Well-Being Scale. Through the first 3 years of follow-up, surgical patients in the high-risk subgroup had a significantly higher probability of death. However, the mortality curves crossed and there was a trend favoring surgical treatment through the remainder of the follow-up. The log-rank test suggested that the 2 groups were not significantly different (p=0.95) in survival. Quality of life data suggested an advantage of LVRS through the first 5 years of follow-up (p<0.01). The combined quality-adjusted survival model favored the medical group for the first few years of follow-up and favored the LVRS group after 4 years. The NETT was stopped early for high-risk patients with severe lung disease. Longer term follow-up suggests that surgical patients in this high-risk subgroup ultimately achieved comparable outcomes. The high risk of death within 30 days of the surgery may discourage use of the procedure for high-risk patients despite the potential for better long-term outcomes.