Background:Elderly patients with type 2 diabetes (TD2M) are prone to developing diabetic kidney disease (DKD). The prevalence of metabolic syndrome increases with age, and metabolic syndrome may also increase the risk of CKD. 
Aims:The study aimed to clarify that if metabolic syndrome promote the progression of DKD in elderly patients with T2DM.
Method:This is an around 5-year retrospective observational cohort study. Metabolic syndrome was defined by the National Cholesterol Education Program Adult Treatment Panel III criteria with the Asian definition of obesity. After excluding patients with macroalbuminuria or eGFR < 15 ml/min/1.73m2, we divided all subjects (age>65y/o) into four groups based on normoalbuminuria or microalbuminuria with or without metabolic syndrome. We defined the progression of DKD by either progression of albuminuria or worsening renal function. Progression of albuminuria was defined by the transition from normo- (<30mg/g) to microalbuminuria (30~300mg/g) or from micro- to macroalbuminuria (>300mg/g). Worsening renal function was defined by a reduction of eGFR to 50% of baseline or doubling of serum creatinine. Multivariate cox-regression analysis was used to identify the risk factors associated with progression of DKD.
Results:460 T2DM patients with a mean age of 72.45 years were included. 
The group with metabolic syndrome had a significant higher body mass index (BMI), triglycerides, blood pressure and urine albumin-creatinine ratio (ACR), but lower HDL-C and eGFR. In the present study, progression of albuminuria was observed in 97 patients (21.2%) and worsened renal function was seen in 23 patients (5.1%). After cox-regression analysis, the multivariable-adjusted HR for progression of albuminuria and for worsened renal function was 1.60(95% C.I.:1.03-2.77 P=0.039) and 3.47(95% C.I.:1.01-11.90 P=0.04), respectively, compared with that without metabolic syndrome. When patients were divided into four groups according to the presence of metabolic syndrome and/or albuminuria, the HR gradually increased. The group with both albuminuria and metabolic syndrome exhibited the highest cumulative incidence of worsening renal function. (P=0.004)
Conclusion:The presence of metabolic syndrome independently predicts the progression of renal disease in elderly patients with T2DM. The use of both metabolic syndrome and albuminuria provides a better risk stratification model for DKD progression than albuminuria alone.

Effect of metabolic syndrome on diabetic nephropathy progression in elderly patients with T2DM - a longitudinal study