Background: A significant body of international evidence suggests that effective primary care systems are associated with better health, lower total health costs, and more equitable access to health care services, which has led the World Health Organization (WHO) to call for strengthening primary care systems globally. Patients with diabetes often seek treatment and have follow-up as outpatients, be it at private or government health facilities. Thus, the objective of this study was to assess the effect of glucose control during outpatient care on first hospitalization risk in type 2 diabetes mellitus (T2DM) patients. Methods: The data used in this retrospective cohort study were obtained from the NonCommunicable Diseases Analysis System (SANENT)® of the Instituto Mexicano del Seguro Social (IMSS). Thus, this work was performed on 3,716,031 DM2 patients, with data regarding a first hospitalization risk estimated using a Cox regression model. Results: The first hospitalization crude risk for diabetes mellitus decreased by 32% in T2DM patients under control through outpatient care (HR: 0.68, 95% CI [0.68,0.69]). Adjusted risk decreased by 23% (HR: 0.77, 95% CI [0.76, 0.77]). Conclusion: The obtained results are consistent with what has been stated in the literature. Outpatient care of diabetic patients at the IMSS should be further strengthened by means of preventive and educational strategies and supported by technology