Longitudinal study of weight, appetite, performance status, and inflammation in advanced gastrointestinal cancer.

There is increasing evidence that, in most patients with advanced cancer, weight loss is associated with an inflammatory response. To examine the temporal relationship between weight loss, appetite, performance status, and the inflammatory response, 50 patients with advanced gastrointestinal cancer with weight loss were observed for six weeks. Patients were grouped according to whether they had lost weight (> 3%, n = 16), were weight stable (< 3% change, n = 25), or gained weight (> 3%, n = 9). At baseline, the group that subsequently lost weight had lower albumin and higher C-reactive protein concentrations (p < 0.05). On follow-up, there was an increase in C-reactive protein concentration and reductions in triceps skinfold thickness and Karnofsky performance status in the weight-losing group (p < 0.05). In contrast, Karnofsky performance status was improved in the group that gained weight (p < 0.05). Over the six to eight weeks, there was a difference in the changes of triceps skinfold thickness (p < 0.05) and Karnofsky performance status (p < 0.01) between the two groups. These results suggest that loss or gain of > 2.5 kg over a six- to eight-week period is required to produce a significant alteration in performance status in weight-losing patients with gastrointestinal cancer. Moreover, the results suggest that the presence of an inflammatory response is associated with further weight loss and the deterioration of performance status.