Clarie B. Hollenbeck

Fasting and postprandial plasma glucose, free fatty acid (FFA), lactate, and insulin concentrations were measured at hourly intervals for 24 h in 27 nonobese individuals-9 with normal glucose tolerance, 9 with mild non-insulin-dependent diabetes mellitus (NIDDM, fasting plasma glucose less than 175 mg/dl), and 9 with severe NIDDM (fasting plasma glucose greater than 250 mg/dl). In addition, hepatic glucose production (HGP) was measured from midnight to 0800 in normal individuals and patients with severe NIDDM. Plasma glucose concentration was highest in patients with severe NIDDM, lowest in those with normal glucose tolerance, and intermediate in those with mild NIDDM (two-way ANOVA, P less than .001). Variations in plasma FFA and lactate levels of the three groups were qualitatively similar, with lowest concentrations seen in normal individuals, intermediate levels in the group with mild NIDDM, and the highest concentration in those with severe NIDDM (two-way ANOVA, P less than .001). Of particular interest was the observation that plasma FFA concentrations were dramatically elevated from midnight to 0800 in patients with severe NIDDM. The 24-h insulin response was significantly increased in patients with mild NIDDM, with comparable values seen in the other two groups. Values for HGP fell progressively throughout the night in normal individuals and patients with severe NIDDM, despite a concomitant decline in plasma glucose and insulin levels. Although the magnitude of the fall in HGP was greater in NIDDM, the absolute value was significantly (P less than .001) greater than normal throughout the period of observation.(ABSTRACT TRUNCATED AT 250 WORDS)

Measurements were made of both glucose disposal (M) during hyperinsulinemic clamp studies and plasma glucose and insulin responses to an oral glucose challenge in 100 individuals with normal glucose tolerance. The subjects were divided into 4 quartiles on the basis of M values, ranging from a low mean (+/- SEM) value of 140 +/- 3 mg/m2 X min (quartile 1) to a high of 349 mg/m2 X min (quartile 4). The plasma insulin response to oral glucose inversely correlated with the M value (r = -0.60; P less than 0.001), being highest in those with the lowest M (quartile 1) and lowest in those with the highest M (quartile 4). On the other hand, the plasma glucose responses of the 4 quartiles were virtually identical. These results document that insulin-stimulated glucose uptake varies widely in subjects with normal glucose tolerance, and that these differences are independent of any change in the plasma glucose response to oral glucose. Furthermore, the results indicate that insulin resistance in normal individuals is associated with hyperinsulinemia.

We examined the relation between insulin resistance, plasma glucose and insulin responses to meals, lipoprotein lipase (LPL) activity, and postprandial lipemia in a population of 37 healthy nondiabetic individuals. Plasma glucose and insulin concentrations were determined at frequent intervals from 8 AM through midnight (breakfast at 8 AM and lunch at noon); resistance to insulin-mediated glucose disposal was determined by measuring the steady-state plasma glucose (SSPG) concentration at the end of a 180-minute infusion of glucose, insulin, and somatostatin; LPL activity was quantified in postheparin plasma; and postprandial concentrations of triglyceride (TG)-rich lipoproteins were assessed by measuring the TG and retinyl palmitate content in plasma and the Svedberg flotation index (Sf) > 400 and Sf 20 to 400 lipoprotein fractions. Significant simple correlation coefficients were found between various estimates of postprandial lipemia and SSPG (r = .38 to .68), daylong insulin response (r = .37 to .58), daylong glucose response (r = .10 to .39), and LPL activity (r = -.08 to -.58). However, when multiple regression analysis was performed, only SSPG remained independently associated with both postprandial TG and retinyl palmitate concentrations. These data provide evidence that insulin resistance plays an important role in regulating the postprandial concentration of TG-rich lipoproteins, including those of intestinal origin.

The purpose of this paper was to compare the ideal body weight (IBW) formulas and published height-weight tables for healthy adults in the United States with the body mass index (BMI) of 22 kg/m2, which is associated with lowest mortality. There are numerous formulas and published height-weight tables available to determine IBW, but there are no published studies comparing the validity of formulas with each other or comparing formulas with BMIs. Data from height-weight tables, weight for specific heights determined by IBW formulas, and weight for BMIs of 20, 22, 25, and 30 kg/m2 at different heights were plotted for both men and women. Slopes based on a range of heights were determined for each formula using relational database software. The value for each slope obtained by linear regression was compared with the BMIs to determine which fit best with BMI of 22 kg/m2. Most height-weight tables and formulas predicted IBWs within the range of BMI of 20-25 kg/m2. However, for shorter heights the formulas were closer to BMI 20 kg/m2 and for taller heights, were closer to BMI 25 kg/m2. Height-weight tables' slopes were closer to the BMI slopes than formula slopes. Robinson's formula appears to be the best equation for calculating desirable/healthy weights in men; however, no formula predicted close to a BMI of 22 kg/m2 for women. Thus, in practice it might be more useful to use BMI ranges instead of IBW formulas for men and women.