INS and obstructive sleep apnea syndrome: Moreover, in men with OSA, the body fat% was positively associated with markers of insulin resistance such as fasting insulin (ρ = 0.745, p < 0.01), HOMA-IR (ρ = 0.708, p < 0.01), and negatively with markers of insulin sensitivity such as Matsuda index (ρ = −0.795, p < 0.001), Stumvoll ISI (ρ = −0.626, p < 0.05).