Objective To explore the most suitable equation in accessing renal function for the elderly type 2 diabetic patients, and its clinical utility in combination with hypersensitive C-reactive protein (hsCRP). Methods The new Cystatin C-based equations for estimated glomerular filtration rate (Cys-eGFR) and conventional predictive equations were compared with isotopic GFR (iGFR) by linear regression analysis, paired t-test, Bland and Altman procedures and non-parametric receiver operating characteristic (ROC) curves. The new Cys-eGFR equation and hsCRP were also incorporated for detecting renal disease in this population. Results The new Cys-eGFR equation had a better relativity with iGFR (r= 0.767, P＜0.001), a less bias (bias: 0.0007, P＞0.05), a higher conformance (2SD: 21.56), higher sensitivity (90.7%) and specificity (88.6%) for diagnosing moderate decrease in renal function. There was a negative relationship between the new Cys-eGFR and hsCRP (r=-0.655, P＜0.01). When the new Cys-eGFR was 67.06 ml· min-1 ·1.73 m-2 and hsCRP was 5.65 mg/L, the combination of Cys-eGFR and hsCRP was better than the combination of serum creatinine and urine albumin/creatinine ratio in screening stage 3 chronic kidney disease (95%vs.46%). Conclusions The combination of new Cys-eGFR equation and hsCRP may screen an early decrease of moderate GFR.

As the overweight and obese population is growing， the incidence of obstructive sleep apnea is rising， and most of the cases are complicated with coronary heart disease and other cardiovascular diseases. The two diseases affect each other and seriously endanger the patients' health， becoming a major public health problem of global concern. It is of great clinical importance to explore the combination of Chinese and Western medicine in the prevention and treatment of coronary heart disease complicated with obstructive sleep apnea syndrome. Researchers have explored the relationship between the two based on traditional Chinese medicine（TCM） theory and found that the two diseases belong to the TCM disease categories of chest impediment and snoring， respectively， and their co-morbidity is associated with the abnormal physiological functions of the heart and lungs. The failure of the heart to govern blood leads to the generation of blood stasis， and that of the lung to govern Qi movement leads to the generation of phlegm. The accumulation of phlegm and blood stasis in the chest causes chest impediment and snoring due to obstruction of the airway. This paper discusses the internal linkage between the pathogenesis of coronary heart disease and obstructive sleep apnea syndrome in Chinese and Western medicine from the TCM theory of heart-lung correlation. Furthermore， this paper proposes the treatment principles of simultaneously treating the heart and lung and activating blood and resolving phlegm， aiming to provide a theoretical basis for the clinical prevention and treatment of coronary heart disease complicated with obstructive sleep apnea.