The overall glucose response was reduced ( treatment difference : -@,@ -LSB- mg/dl -RSB- min -LSB- @ % confidence interval , -@,@ to -@ -RSB- ; P = @ ) and insulin sensitivity was improved ( treatment difference : @ -LSB- mU/L -RSB- ( -@ ) min ( -@ ) -LSB- @ % confidence interval , @-@ @ -RSB- ; P = @ ) with CPAP as compared with placebo .