Classification rule for ten year MACE Risk in primary care tarragona older adults with type2 diabetes: a CHAID decision-tree analysis.

Background: Cardiovascular disease is the leading cause of mortality among individuals with Type 2 Diabetes Mellitus (T2DM). This study developed a simple tool to predict the 10-year risk of major adverse cardiovascular events (MACE) in T2DM patients over 60 years within primary care.

Methods: A retrospective cohort study was conducted on patients with T2DM who were over 60 years old in Tarragona, spanning from 01/01/2009-31/12/2018. Primary outcome was MACE, which included acute myocardial infarction (AMI), stroke, and cardiovascular death, all of which were identified using ICD-9 diagnostic codes. Other variables were age, sex, comorbidities, risk factors, as well as clinical and laboratory parameters. A Chi-Square Automatic Interaction Detector (CHAID) decision tree classification was utilized to assess the 10-year risk of developing a new MACE.

Results: Five thousand five hundred fifty-four patients with T2DM were identified. Among the 4,666 with T2DM and without previous MACE, 779 patients went on to develop a new MACE. The CHAID model categorizes individuals into three risk groups based on the primary predictor variable, which is age. For patients under the age of 71 with hypertension, having HDL-c levels less than 39 mg/dL increases the risk of developing a new MACE to 19.9%. Among individuals aged 71 to 75 years, having fasting glucose levels greater than 177 mg/dL elevates the risk to 27.2%.

Conclusion: Classification trees based on CHAID allow for the development of decision rules and simplify the stratification of cardiovascular risk in patients with T2DM, making it a valuable tool for risk assessment within a primary care setting.