Aim: Precise monthly achievement rates for reaching guideline goals for HbA1c, blood pressure (BP), and cholesterol levels remain unknown. We evaluated achievement rates on a monthly basis in patients with type 2 diabetes mellitus (T2DM) and explored related factors.

Material and Methods: This retrospective study initially analyzed data on 104,601 patients with T2DM throughout Japan (38 medical clinics). Patients whose HbA1c, BP, and low-density lipoprotein (LDL)-cholesterol were measured ≥12 times during a 2-year period were included. We evaluated monthly achievement rates. Achieved goals were defined as HbA1c <7%, BP <130/80 mmHg, and LDL-cholesterol <100 mg/dL. Achievement of all goals was expressed as the "all ABC achievement."

Results: A total of 4,678 patients were analyzed. The achievement rates of all ABC, HbA1c, BP, and LDL-cholesterol exhibited seasonal variations with the lowest rates in winter, with those for systolic BP (SBP) being particularly low (all ABC, summer 15.6%, winter 9.6%; HbA1c, 53.1%, 48.9%; SBP, 56.6%, 40.9%; LDL-cholesterol, 50.8%, 47.2%). In the multiple logistic regression analysis, in winter, BMI ≥25 kg/m2 (BMI 25-30 kg/m2, odds ratio 0.45 [0.29-0.70], p < 0.001; BMI ≥30 kg/m2, 0.35 [0.22-0.57], p < 0.001) and diabetes duration ≥10 years (0.53 [0.37-0.76], p < 0.001) were independently related to lower achievement rates for HbA1c, and age ≥65 years (0.47 [95% CI 0.34-0.63], p < 0.001) was independently related to decreased achievement rates for SBP. Insulin and sulfonylurea use were independently associated with the decreased all ABC achievement rates in both summer and winter.

Conclusion: This study showed that in patients with T2DM, the achievement rates for blood glucose, BP, and lipid goal levels varied seasonally. Seasonal variations in the all ABC achievement rate should be considered when managing T2DM in ordinary clinical practices.


D. Matsutani: None. M. Sakamoto: None. S. Minato: None. Y. Tsujimoto: None. Y. Kayama: None. K. Utsunomiya: None. M. Nishikawa: None.

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