Rationale: To study the relationship between emphysema and/or airflow obstruction and lung cancer in a high-risk population. Objective: We studied lung cancer related to radiographic emphysema and spirometric airflow obstruction in tobacco-exposed persons who were screened for lung cancer using chest computed tomography (CT). Methods: Subjects completed questionnaires, spirometry, and lowdose helical chest CT. CT scans were scored for emphysema based on National Emphysema Treatment Trial criteria. Multiple logistic regressions estimated the independent associations between various factors, including radiographic emphysema and airflow obstruction, and subsequent lung cancer diagnosis. Measurements and Main Results: Among 3,638 subjects, 57.5, 18.8, 14.6, and 9.1% had no, trace, mild, and moderate-severe emphysema, and 57.3, 13.6, 22.8, and 6.4% had no, mild (Global Initiative for Chronic Obstructive Lung Disease [GOLD] I), moderate (GOLD II), and severe (GOLD III-IV) airflow obstruction. Of 3,638 subjects, 99 (2.7%) received a lung cancer diagnosis. Adjusting for sex, age, years of cigarette smoking, and number of cigarettes smoked daily, logistic regression showed the expected lung cancer association with the presence of airflow obstruction (GOLD I-IV, odds ratio [OR], 2.09; 95% confidence interval [CI], 1.33-3.27). A second logistic regression showed lung cancer related to emphysema (OR, 3.56; 95% CI, 2.21-5.73). After additional adjustments for GOLD class, emphysema remained a strong and statistically significant factor related to lung cancer (OR, 3.14; 95% CI, 1.91-5.15). Conclusions: Emphysema on CT scan and airflow obstruction on spirometry are related to lung cancer in a high-risk population. Emphysema is independently related to lung cancer. Both radiographic emphysema and airflow obstruction should be considered when assessing lung cancer risk.

This study reviews the relationship between body weight, pulmonary function, and survival in the recent clinical trial of intermittent positive pressure breathing (IPPB). We related body weight, expressed as a percent of the ideal (%IBW), to the numerous other features of the disease recorded in this data set. Body weight was directly related to FEV1 (p = 0.0001), so that all subsequent analyses of body weight had to first consider FEV1. Mortality appeared to be influenced by body weight independent of FEV1. In patients with %FEV1 less than 35, mortality increased with decreasing body weight (p = 0.093), and this relationship was stronger in patients with %FEV1 35 to 47 (p = 0.048) and even stronger in patients with %FEV1 greater than 47 (p = 0.007). After adjusting for FEV1, body weight was a powerful positive correlate with exercise capacity (p = 0.0001). Body weight was also inversely related to %TLC (p = 0.0408) after adjusting for FEV1. Body weight was a powerful predictor of diffusing capacity (p = 0.0001) in patients with the same FEV1. These results support the hypothesis that factors related to nutritional status are an independent influence on the course of COPD.

There are no established chemopreventive agents for lung cancer, the leading cause of cancer death in the United States. Prostacyclin levels are low in lung cancer and supplementation prevents lung cancer in preclinical models. We carried out a multicenter double-blind, randomized, phase II placebo-controlled trial of oral iloprost in current or former smokers with sputum cytologic atypia or endobronchial dysplasia. Bronchoscopy was performed at study entry and after completion of six months of therapy. Within each subject, the results were calculated by using the average score of all biopsies (Avg), the worst biopsy score (Max), and the dysplasia index (DI). Change in Avg was the primary end point, evaluated in all subjects, as well as in current and former smokers. The accrual goal of 152 subjects was reached and 125 completed both bronchoscopies (60/75 iloprost, 65/77 placebo). Treatment groups were well matched for age, tobacco exposure, and baseline histology. Baseline histology was significantly worse for current smokers (Avg 3.0) than former smokers (Avg 2.1). When compared with placebo, former smokers receiving oral iloprost exhibited a significantly greater improvement in Avg (0.41 units better, P = 0.010), in Max (1.10 units better, P = 0.002), and in DI (12.45%, P = 0.006). No histologic improvement occurred in current smokers. Oral iloprost significantly improves endobronchial histology in former smokers and deserves further study to determine if it can prevent the development of lung cancer.

Patients with severe chronic obstructive pulmonary disease (COPD) commonly experience weight loss. An increased energy expenditure for respiration might explain the increased caloric requirements and weight loss seen in this patient population. We measured the oxygen cost of augmenting ventilation (O2 cost) using an open circuit technique with dead-space stimulation of ventilation in nine normally nourished (greater than 90% ideal body weight) and in 10 malnourished (less than 90% ideal body weight) patients with COPD as well as in seven normal control subjects. O2 cost was significantly elevated in the malnourished patients with COPD (4.28 +/- 0.98 ml O2/L ventilation) relative to the normally nourished group (2.61 +/- 1.07) and the normal control subjects (1.23 +/- 0.51) (p less than 0.001). The measured resting energy expenditure (REEmeas) was also increased compared with predicted values (REEpred) in the malnourished population (REEmeas/REEpred = 94.57 +/- 6.21% for control subjects, 105.5 +/- 19.66% for normally nourished patients with COPD, and 119.4 +/- 11.69% for malnourished patients with COPD) (p less than 0.005). The malnourished population was characterized by a greater degree of hyperinflation (RV/TLC = 0.55 +/- 0.09 for normally nourished versus 0.69 +/- 0.06 for malnourished patients) and inspiratory muscle weakness (PImax = 51 +/- 16.5 for the normally nourished and 34 +/- 12.2 for the malnourished population). We conclude that malnourished patients with COPD are characterized by a relative increase in resting energy requirements and, specifically, increased energy requirements for augmenting ventilation. This increase in energy requirements may result from the increased mechanical work load associated with severe COPD and/or a reduced ventilatory muscle efficiency.

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The N contained in winter cover crops (particularly legumes) is a potentially important source of N for succeeding crops. The purpose of this study was to determine N release from crimson clover (Trifolium incarnatum L.) residue under no‐tillage and conventional tillage conditions. Residues contained in nylon mesh (53 µm) bags placed either on the surface of no‐tillage plots or buried at plowlayer depth in conventional tillage plots were removed for dry matter, C, and N determinations at 1, 2, 4, 8, and 16 weeks after placement in mid‐May. The rate of N disappearance was more rapid under conventional than no‐tillage conditions. The percentage of initial residue N remaining at 4 and 16 weeks under conventional tillage conditions was 40 and 31, respectively. The corresponding values for no‐tillage were 63 and 36% at 4 and 16 weeks. The C/N ratio of the residue remained relatively unchanged over the 16‐week period under no‐tillage conditions. However, under conventional tillage conditions, the C/N ratio declined from 15.9 to 12.7. Under humid, subtropical conditions, release of N from both surface and buried residue from winter legumes, is sufficiently rapid to be of significant benefit to the summer crop.

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Rationale: Patients with chronic obstructive pulmonary disease (COPD) are at high risk for lung cancer (LC) and represent a potential target to improve the diagnostic yield of screening programs.Objectives: To develop a predictive score for LC risk for patients with COPD.Methods: The Pamplona International Early Lung Cancer Detection Program (P-IELCAP) and the Pittsburgh Lung Screening Study (PLuSS) databases were analyzed. Only patients with COPD on spirometry were included. By logistic regression we determined which factors were independently associated with LC in PLuSS and developed a COPD LC screening score (COPD-LUCSS) to be validated in P-IELCAP.Measurements and Main Results: By regression analysis, age greater than 60, body mass index less than 25 kg/m 2 , pack-years history greater than 60, and emphysema presence were independently associated with LC diagnosis and integrated into the COPD-LUCSS, which ranges from 0 to 10 points. Two COPD-LUCSS risk categories were proposed: low risk (scores 0-6) and high risk (scores 7-10). In comparison with low-risk patients, in both cohorts LC risk increased 3.5-fold in the high-risk category.Conclusions: The COPD-LUCSS is a good predictor of LC risk in patients with COPD participating in LC screening programs. Validation in two different populations adds strength to the findings.