CHI3L1 and diabetes mellitus: After adjustment for age, sex, BMI, medical history of hypertension, diabetes, coronary heart disease, dyslipidemia, smoking, and alcohol consumption, YKL-40 level remained significantly associated with carotid plaque instability (quartile 3: OR 2.71, 95% CI 1.78–4.11; quartile 4: OR 2.14, 95% CI 1.39–3.28) in Model 3.