Background: Type 2 diabetes mellitus (T2DM) is a major contributor to non-communicable disease burden worldwide, with sedentary behavior increasingly implicated as an independent risk factor distinct from physical inactivity.

Objective: This simulated case-control study examines the association between sedentary lifestyle patterns and risk of T2DM among urban adults.

Method: A hypothetical case-control design was used, comparing 150 simulated T2DM cases with 150 simulated non-diabetic controls, matched for age and sex. Simulated data on daily sitting time, screen time, occupational activity, and dietary habits were analyzed using descriptive statistics, chi-square tests, and binary logistic regression.

Results: In this simulated dataset, cases reported higher mean daily sitting time (7.8 ± 2.1 hours) than controls (5.4 ± 1.9 hours). Logistic regression suggested sedentary time exceeding 6 hours/day was associated with elevated odds of T2DM (simulated OR = 2.34, 95% CI: 1.52–3.61, p < 0.001), independent of body mass index and family history.