Prevalence and Development of Cachexia Before and After Diagnosis of Non-small Cell Lung Cancer

Objective: Cachexia is commonly defined based on weight loss at the time of cancer diagnosis. However, regular weight measurements before cancer diagnosis are often lacking and may be subject to recall bias if retrospectively self-reported by patients. To analyze the development and progression of cachexia, we employ body weight trajectories from 1 year before and after diagnosis of non-small cell lung cancer (NSCLC). We hypothesized that cachexia could be detected as early as 1 year before NSCLC diagnosis and that cachexia prevalence would increase in the year following diagnosis. Methods: This retrospective study included consecutive patients with NSCLC treated at UTSW between 2005 and 2019 who had body weight measurements before and after NSCLC diagnosis recorded in their electronic health records. Weights were binned in 3-month intervals. Cachexia was defined per the International Consensus Definition of cachexia, that is, loss of >5% body weight 12 months preceding cancer diagnosis for patients with BMI ≥20 kg/m ² or weight loss of >2% for patients with a BMI <20 kg/m ². The association of disease stage and primary treatment with weight changes was investigated. Results: Among 4294 patients screened, 661 patients were included in the final analysis. Patients had a mean age of 69.3 (SD: 10.6) years, and a majority were current/former smokers (83%), identified as white (76%), and were diagnosed with either stage I (47%) or stage IV (28%) nonsquamous NSCLC (78%). At cancer diagnosis, 28% (n=183) presented with cachexia, having incurred a mean loss of 8.6 (SEM: 0.4%) (P<0.0001) of body weight within the year before cancer diagnosis. Weight loss after cancer diagnosis was comparable in patients with and without cachexia at cancer diagnosis (P=0.05). By 12 months postcancer diagnosis, 58% of patients (n=383) met the criteria for cachexia based on weight loss. Weight loss consistent with cachexia occurred over a median period of 220 (IQR: 265) days. Conclusion: Weight loss in patients with cachexia at NSCLC diagnosis may commence as early as 12 months before cancer diagnosis. Within a year after a cancer diagnosis, more than half of patients develop cachexia, particularly those with advanced disease. These findings support the integration of early nutritional and pharmacological interventions in patients with NSCLC.