Association Between Insulin Resistance And Bmi With Fev1 In Non-Hypoxemic Copd Out-Patients

Objectives This study was conducted to determine the impact of insulin resistance using Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) score and BMI in non-hypoxemic out-patients with COPD on FEV1 using linear and polynomial regressions and to determine their correlation.Methods COPD patients of both genders were included after informed consent. Fasting blood sugar and serum insulin were done to calculate HOMA-IR, which were segregated into two groups of >= 3 and < 3 labeled insulin resistance present and absent, these were compared with BMI. Patients were segregated into GOLD Grade 1-4 per GOLD Guidelines and compared with HOMA-IR and BMI. Curve and linear regressions, multivariate and univariate analysis of HOMA-IR with BMI, FVC, and FEV1 were done.Results A total of 273 subjects were inducted after informed consent. There was a linear correlation between HOMA-IR and BMI (r(2) 0.498, P < 0.001) and nonlinear correlation between HOMA-IR and FEV1 (r(2) 0. 617, P < 0.001) which showed little evidence of association above FEV1 > 60 predicted, but a clear negative association below that. Significant increase in HOMA-IR was seen from GOLD-2 to 3 and from GOLD-3 to 4 classes. The impact of HOMA-IR on FEV1 was 49.9% (P < 0.001) on FVC was 43.7%.Conclusions The results indicate that there is a high prevalence of IR in non-hypoxemic COPD. A nonlinear association is present between FEV1 and HOMA-IR which is most evident with FEV1 <60% predicted.