The Effects and Safety of Diabetic GUideline Algorithm Implementation in the Community (GUARD-Community) study is a 2-arm, cluster-randomized control trial to evaluate the effect and safety of guideline algorithm intervention performed by primary care physicians on cardiovascular and renal outcomes in elderly patients with high risk in community.

Diabetes is an important public health concern. Elderly diabetic patients are characterized by a long duration and complications, including chronic kidney disease and/or cardiovascular disease. In the past 30 years, the guidelines of CDS, EASD or ADA have been frequently updated. The latest guideline on pharmacological algorithm recommend that patients with cardiovascular, renal disease or very high/high CV risk patients should be treated with anti-diabetic drugs presenting target organ protection, including SGLT2i and GLP1RA. And the guideline recommend comprehensive control of the cardiovascular risk factors, such as hypertension and dyslipidemia.

This GUARD-Community study is a community based cluster-randomized controlled trial and will enroll 5600 or more participants in more than 120 clusters aged ≥ 65 years with T2DM and complicated with high/very high cardiovascular risk factors . The trial will evaluate the the effects and safety of intensive "Guideline" algorithm implementation on CVD and renal outcomes. The primary hypothesis is that guideline algorithm intervention implemented by primary care physicians will significantly reduce the risk of 4-point MACE (comprised of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke or hospitalization of heart failure) rates. In Phase 1 study, the control of blood sugar, blood pressure and lipids will be evaluated at 18 months after intervention. In Phase 2 study, the CVD and renal outcomes will be evaluated at 3 years. The study will last for 4 years.

Inclusion Criteria:

• ①Males or females aged 65 and above (≥65) receive treatment from the local community health service center;
• ②Diagnosed type 2 diabetes (ADA criteria):
• A. Typical symptoms of diabetes + random blood sugar ≥ 11.1mmol/L;
• B. Fasting blood glucose (FPG) ≥ 7.0mmol/L (fasting blood glucose is defined as no caloric intake within 8 hours);
• C. Oral glucose tolerance test 2h blood glucose (OGTT) ≥ 11.1mmol/L (2h after meal);
• D. have been treated with antidiabetic drugs;
• Each blood sugar test must be repeated to confirm the diagnosis;
• ③Complicated with chronic kidney disease and/or very high/high risk of cardiovascular disease, meet any one of the following:
• A. ASCVD, including coronary heart disease, cerebral infarction, peripheral vascular disease;
• B. Or target organ damage (albuminuria, renal impairment with eGFR ≥ 30 ml/min/1.73m2, left ventricular hypertrophy or retinopathy);
• C. ≥ 3 major risk factors (age ≥ 65 years old, hypertension, dyslipidemia, smoking, obesity );
• D. Diabetes duration ≥ 10 years, with any one traditional cardiovascular risk factor such as advanced age, obesity, smoking, sedentary, family history of cardiovascular disease, hypertension, abnormal lipid metabolism.

Exclusion Criteria:

• ①Pregnant women or women planning to become pregnant;
• ②eGFR<30 mL/min/1.73m2 (CKD-EPI formula);
• ③Patient cannot be followed up for 36 months (due to health condition or migration);
• ④Unwilling or unable to sign the informed consent;
• ⑤Type 1 diabetes;

The data will be available from the principle investigator on reasonable request.

Outcome Assessment Committee members will be blinded to outcome assignment.