Isolated involuntary weight loss: Clinical characteristics and predictors of malignancy.

Abstract

Introduction: Involuntary weight loss (IPP) is a common problem in outpatient clinics. The objective of our study is to analyze the factors related to the presence of cancer as a cause of PPI in this type of patients.

Methods: Retrospective, descriptive, observational, multicenter study. We analyzed epidemiological and clinical variables of all patients referred to the Internal Medicine clinic for IWL from October 2017 to December 2022.

 Results: We included 366 patients, 49% being male and a mean age of 62.6 (17.4) years. Cancer was responsible for the IWL in 33 patients (9%), non-malignant organic pathology in 120 patients (32.8%), psychiatric diseases in 90 patients (24.6%), and no cause was found in 123 patients (33.6%). Overall mortality at 12 months was 5.5%, being significantly higher in the group of patients whose etiology was a cancerous process compared to the other pathologies (39.4% vs. 8,2%, p<0.001). The logistic regression analysis determined that the predictors of cancer as a cause of IWL were male sex [OR 0.34, (95% CI 0.144-0.802), p<0.014], the presence of anorexia [OR 3.565, (95% CI 1.539-8.260), p<0.003], leukocyte concentration [OR 1.156, (95% CI 1.105-1.133), p<0.042] and hemoglobin concentration in blood [OR 0.593, (95% CI 0.479-0.734), p <0.001].

 Conclusions: 9% of the patients with IWL had a cancer as the underlying cause, finding predictors of this. Mortality at one year was significantly higher in this subgroup of patients.