INSULIN-SECRETION, GLUCOSE-PRODUCTION, AND INSULIN SENSITIVITY IN UNDERWEIGHT AND NORMAL-WEIGHT VOLUNTEERS, AND IN UNDERWEIGHT AND NORMAL-WEIGHT CANCER-PATIENTS - A CLINICAL RESEARCH-CENTER STUDY

Severe malnutrition (<65% ideal body weight [IBW]) is associated with reduced insulin secretion, decreased receptor affinity, and glucose in tolerance. To characterize the abnormality of mild malnutrition in ter ms of insulin action, both the insulin sensitivity index and insulin s ecretion were measured in 15 underweight and 15 normal-weight voluntee rs. Ten patients had localized squamous cell carcinomas of the head an d neck, and 20 were normal controls. After a 10-hour overnight fast, a ll volunteers were studied using Bergman's modified intravenous (IV) g lucose tolerance test (IVGTT). Body weight and diagnosis were compared using a 2 x 2 ANOVA. The acute insulin response to IV glucose was red uced in normal-weight and underweight cancer patients by approximately 40% to 50% (P < .05). Both groups of cancer patients had a significan tly reduced rate of glucose disposal (1.25 +/- 0.29 and 1.27 +/- 0.23 %/min) compared with the healthy volunteers (1.82 +/- 0.21 and 1.81 +/ - 0.24 %/min, respectively, P < .05). Glucose production (GP) was sign ificantly increased in the underweight cancer patients versus the weig ht-matched volunteers (13.9 +/- 1.3 v 10.8 +/- 0.5 mu mol/kg/min, P < .05). Normal-weight and underweight cancer patients had a 32% to 44% r eduction in insulin sensitivity (P < .05). In contrast to the effects of cancer, underweight controls had twice the insulin sensitivity comp ared with normal-weight controls (P < .01). Since insulin secretion de creased in underweight controls, the increased insulin sensitivity may have been due to an increased insulin action and to factors associate d with leanness. Copyright (C) 1997 by W.B. Saunders Company.