Table 1.

Interventional and observational studies on glycemic control in type 2 diabetes mellitus patients and carotid intima media thickness outcomes

Ref.	Year	HbA1c (%), mean ± SD	Type of study	Intervention	Sample size	Main findings
Nambi et al[10]	2010	Glucose levels 105 ± 30.7 mg/dL	Population-based cohort	Risk prediction model: Whether cIMT and plaque improves CHD risk prediction when added to traditional risk factors	13145	0.07 mm greater cIMT in the presence of DM
Kawasumi et al[15]	2006	5.8-6.4	Cohort	Insulin, sulfonylureas, nateglinide, metformin, pioglitazone, α-GI for 3 yr	100	HbA1c improvement > 0.2% prevents cIMT increase
Di Pino et al[14]	2014	5.7-6.4 or > 6.5	Cohort	Subjects without a previous history of diabetes were stratified into three groups according to HbA1c levels	274	Impaired cIMT even in pre-diabetes
Sharma and Pandita[16]	2017	> 7 or < 7	Cohort	T2DM duration > 1 yr or newly diagnosed, age 10-25 yr	45	HbA1c and longer diabetes duration affect cIMT
Di Flaviani et al[17]	2011	6.7 ± 1.3	Cohort	Continuous glucose monitoring; Diet and/or metformin	26	No association was observed between cIMT any glucose variability or overall glycemic load
Langenfeld et al[19]	2005	7.5 ± 0.9	RCT	Pioglitazone 45 mg/d vs glimepiride 2.7 ± 1.6 mg/d for 12-24 wk	173	Pioglitazone reduces cIMT independently of improvement in glycemic control
Oyama et al[20]	2016	6.2 < HbA1c < 9.4%	Multicenter PROBE	Sitagliptin 25 to 100 mg/d vs conventional treatment over 2 yr	442	Sitagliptin had no additional effect on cIMT progression
Rizzo et al[23]	2014	8.4 ± 0.8	Prospective pilot	Liraglutide added on metformin over 8 mo	64	Beneficial role in plaque formation and inflammation

α-GI: Alpha-glucosidase inhibitors; CHD: Coronary heart disease; cIMT: Carotid intima media thickness; CVD: Cardiovascular disease; DM: Diabetes mellitus; LDL: Low-density lipoprotein; RCT: Randomized controlled trial; SD: Standard deviation; T2DM: Type 2 diabetes mellitus.