Lifestyle and Follow-Up Gaps Contribute to Poor Glycemic Control in Patients With Type 2 Diabetes Mellitus in Southwestern Bangladesh

​​​Background Type 2 diabetes mellitus (T2DM) is a growing global health concern, particularly in low- and middle-income countries, where the rate of poor glycemic control is high. Lifestyle modifications and regular follow-ups are essential for effective management and prevention of complications. Methodology This cross-sectional study was conducted at a tertiary care facility from March to December 2024, enrolling 360 adults with T2DM using non-probability purposive sampling. Data on demographics, clinical history, and biochemical parameters (glycated hemoglobin (HbA1c), plasma glucose) were collected to assess glycemic control, with an HbA1c threshold of 7%. Ethical approval and informed consent were obtained, and data were analyzed using SPSS version 25 (IBM Corp., Armonk, NY, USA). Results A total of 360 adults with T2DM participated in the study, with a mean age of 48.4 years. Most participants were female (62.7%) and overweight or obese (78%). The median duration of diabetes was five years, and 60% of patients had at least one comorbidity. Poor glycemic control was found in 82.7% based on HbA1c and 90.2% based on plasma glucose. Better glycemic control was significantly associated with factors such as shorter diabetes duration, medication adherence, diabetes education, diet, exercise, and regular follow-up. Logistic regression revealed that age, diabetes duration, diabetic diet (odds ratio (OR) = 5.6), regular exercise (OR = 3.8), and regular follow-up (OR = 8.5) were significantly associated with better glycemic control. Conclusions The study revealed a high prevalence of poor glycemic control among T2DM patients in southwestern Bangladesh. Targeted interventions, especially lifestyle and regular follow-up protocols, are urgently needed to improve diabetes management and prevent complications.