Obesity Epidemiology

Table 18.3 Prospective Epidemiologic Studies on Insulin Resistance and Weight GainFirst Author(Year) Study Population Exposure Outcome AssociationsSwinburnet al. (1991) 30Valdez (1994) 31Arizona Pima IndiansFU = 3.5 yAge = 25 yBMI = 34192 nondiabetic men (n = 104) andwomen (n = 88)San Antonio Heart Study (MexicanAmerican/non-Hispanic white)FU = 8 yAge = 25-64 yBMI = 24-281493 nondiabetic men and womenSchwartz(1995) 32 Arizona Pima IndiansFU = 3 yAge = 25 yBMI = 3497 nondiabetic men (n = 64) and women(n = 33)Hoag (1995) 33San Luis Valley Diabetes Study(Hispanic/non-Hispanic white)FU = 4 yAge = 53 yBMI = 26789 nondiabetic men and womenHyperinsulinemic, euglycemicclamp insulin resistance(IR = below regression line forglucose disposal regressed onweight)Percent weightchangeIncreased IR associated with reducedrate of weight gain (P < .0001)Fasting insulin Weight change Increased fasting insulin associatedwith a lower likelihood of gainingweight among obese subjects(P < .001)Insulin secretion:MTT AUCOGTT AUCAIRg (acute insulin responseto glucose)IR:Submax MMax MPercentage ofweight changePercentage of fatmass changeAll three measures of reduced insulinsecretion significantly predictedincreased percent weight change inmultivariate linear regression analyses(P < .05).Measures of IR predictive of weightgain in univariate analyses, but notmultivariate analysesFasting insulin Weight change Higher initial fasting insulin related tolower subsequent rates of weight gainin nonglucose tolerant (NGT) persons(P = .006)(continued)