Prevalence of normoglycemic, prediabetic and diabetic A1c levels

Table 1 Definitions of current study variables within different groups

Different groups	Responses and A1c levels
Prediabetes group
Self-reported Prediabetes	“Yes” response to “ever told you have prediabetes,” and a “no” response to “doctor told you have diabetes.”
Reversed prediabetes	Self-reported “yes” response to “ever told you have prediabetes,”“no” response to “doctor told you have diabetes” and have normoglycemic A1c levels (< 5.7%).
Diagnosed prediabetes	Self-reported “yes” response to “ever told you have prediabetes,”“no” response to “doctor told you have diabetes” and have prediabetic A1c levels (5.7%-6.4%).
Undiagnosed diabetes	Self-reported “yes” response to “ever told you have prediabetes,”“no” response to “doctor told you have diabetes” and have diabetic A1c levels (≥ 6.5%).
Non-Prediabetes group
Self-reported non-prediabetes	“No” response to “ever told you have prediabetes,” and a “no” response to “doctor told you have diabetes.”
Not having prediabetes	Self-reported “no” response to “ever told you have prediabetes,”“no” response to “doctor told you have diabetes” and have normoglycemic A1c levels (< 5.7%).
Undiagnosed prediabetes	Self-reported “no” response to “ever told you have prediabetes,”“no” response to “doctor told you have diabetes” and have prediabetic A1c levels (5.7%-6.4%).
Undiagnosed diabetes	Self-reported “no” response to “ever told you have prediabetes,”“no” response to “doctor told you have diabetes” and have diabetic A1c levels (≥ 6.5%).

Table 2 United States Population 20 years and older with self-reported prediabetes n (%)

Glycated hemoglobin (A1c)	Self-report of: “Yes” ever being told they have prediabetes; and “No” being told they had diabetes
	NHANES 2007-2008 Weighted	NHANES 2009-2010 Weighted
Normoglycemic levels (< 5.7%) reversed prediabetes	3565229/6566166 (54.3)	3281804/7569333 (43.4)
Prediabetic levels (5.7%-6.4%) prediabetes	2435163/6566166 (37.1)	3071030/7569333 (40.6)
Diabetic levels (> 6.5%) undiag nosed/unaware diabetes	564774/6566166 (8.6)	1216499/7569333 (16.0)
Total	n = 6566166	n = 7569333

Table 3 Percentage of different ethnic groups 20 years and older with self-reported prediabetes n (%)

NHANES 2007-2008			NHANES 2009-2010
Ethnicity	Weighted	SD	Weighted	SD	P
Mexican American	325142/6566166 (5.0)		379370/7569333 (5.0)
Normoglycemic A1c (< 5.7%)	102664/325142 (31.6)	0.33	154730/379370 (40.8)	0.43	< 0.0001
Prediabetic A1c (5.7%-6.4%)	140099/325142 (43.1)	0.46	161539/379370 (42.6)	0.43	< 0.0001
Diabetic A1c (≥ 6.5%)	82379/325142 (25.3)	0.44	63101/379370 (16.6)	0.22	0.8521
Other Hispanic	172116/6566166 (2.6)		175097/7569333 (2.3)
Normoglycemic A1c (< 5.7%)	94137/172116 (54.7)	0.16	104638/175097 (59.8)	0.43	0.3841
Prediabetic A1c (5.7%-6.4%)	73430/172116 (42.7)	0.43	56802/175097 (32.4)	0.42	0.3472
Diabetic A1c (≥ 6.5%)	4549/172116 (2.6)	0.36	13657/175097 (7.8)	0.12	0.9457
Non-Hispanic White	4757294/6566166 (72.5)		5976593/7569333 (79.0)
Normoglycemic A1c (< 5.7%)	2571794/4757294 (54)	0.46	2696814/5976593 (45.1)	0.4	0.7869
Prediabetic A1c (5.7%-6.4%)	1872875/4757294 (39.4)	0.43	2311252/5976593 (38.7)	0.4	0.0222
Diabetic A1c (≥ 6.5%)	312625/4757294 (6.6)	0.23	968527/5976593 (16.2)	0.09	0.0024
Non-Hispanic Black	645476/6566166 (9.8)		757648/7569333 (10)
Normoglycemic A1c (< 5.7%)	269742/645476 (41.8%)	0.46	212317/757648 (28%)	0.44	< 0.0001
Prediabetic A1c (5.7%-6.4%)	210513/645476 (32.6%)	0.42	483049/757648 (63.8%)	0.44	< 0.0001
Diabetic A1c (≥ 6.5%)	165221/645476 (25.6%)	0.43	62282/757648 (8.2%)	0.16	< 0.0001
Other/Multi-Racial	666138/6566166 (10.1%)		280625/7569333 (3.7%)
Normoglycemic A1c (< 5.7%)	527892/666138 (79.2%)	0.27	113305/280625 (40.3%)	0.41	0.0104
Prediabetic A1c (5.7%-6.4%)	138246/666138 (20.8%)	0.27	58388/280625 (20.8%)	0.41	0.7737
Diabetic A1c (≥ 6.5%)	0/666138 (0.0%)	0.00	108932/280625 (38.8%)	0.13	0.0067
Total	n = 6566166		n = 7569333

SD: Shine-dalgarnosequence.

Table 4 United States population 20 years and older with self-reported non-prediabetes n (%)

Glycated hemoglobin (A1c)	Self-report of: “No” ever being told they have prediabetes; and “No” being told they had diabetes
	2007-2008 weighted	2009-2010 weighted
Normoglycemic levels (< 5.7%) no prediabetes or diabetes	128918166/164914962 (78.2)	122536437/161120813 (76.0)
Prediabetic levels (5.7%-6.4%) undiagnosed/unaware prediabetes	32926568/164914962 (19.9)	36065705/161120813 (22.4)
Diabetic levels (≥ 6.5%) undiagnosed/unaware diabetes	3070228/164914962 (1.9)	2518671/161120813 (1.6)
Total	n = 164914962	n = 161120813

Table 5 Different ethnic groups 20 years and older with self-reported non-prediabetes n (%)

NHANES 2007-2008		NHANES 2009-2010
Ethnicity	Weighted	Weighted	P
Mexican American	15104701/164914962 (9.2)	15411565/161120804 (9.6)
Normal (A1c ≤ 5.7%)	12524514/15104701 (82.9)	11245974/15411161 (73)	< 0.0001
Prediabetes (A1c= 5.7%-6.4%)	2248885/15104701 (14.9)	3608202/15411161 (23.4)	< 0.0001
Diabetes (A1c ≥ 6.5%)	331302/15104701 (2.2)	557389/15411161 (3.6)	< 0.0001
Other Hispanic	8878061/164914962 (5.4)	8645012/161120804 (5.4)
Normal (A1c ≤ 5.7%)	7011142/8878061 (78.9)	6519914/8645012 (75.4)	< 0.0001
Prediabetes (A1c= 5.7%-6.4%)	1655906/8878061 (18.7)	1950442/8645012 (22.6)	< 0.0001
Diabetes (A1c ≥ 6.5%)	211013/8878061 (2.4)	174656/8645012 (2)	< 0.0001
Non-Hispanic White	113923737/164914962 (69.1)	109714993/161120804 (68.1)
Normal (A1c ≤ 5.7%)	90029378/113923737 (79)	85687554/109714993 (78.1)	< 0.0001
Prediabetes (A1c = 5.7%-6.4%)	22273553/113923737 (19.6)	22770821/109714993 (20.8)	< 0.0001
Diabetes (A1c ≥ 6.5%)	1620806/113923737 (1.4)	1256618/109714993 (1.1)	< 0.0001
Non-Hispanic Black	17698774/164914962 (10.7)	17766570/161120804 (11)
Normal (A1c ≤ 5.7%)	12238510/17698774 (69.1)	11922107/17766570 (67.1)	< 0.0001
Prediabetes (A1c = 5.7%-6.4%)	4864294/17698774 (27.5)	5436479/17766570 (30.6)	< 0.0001
Diabetes (A1c ≥ 6.5%)	595970/17698774 (3.4)	407984/17766570 (2.3)	< 0.0001
Other/Multi-Racial	9309689/164914962 (5.6)	9582664/161120804 (5.9)
Normal (A1c ≤ 5.7%)	7114622/9309689 (76.4)	7160888/9582664 (74.7)	< 0.0001
Prediabetes (A1c = 5.7%-6.4%)	1883930/9309689 (20.2)	2299761/9582664 (24)	< 0.0001
Diabetes (A1c ≥ 6.5%)	311137/9309689 (3.4)	112015/9582664 (1.2)	< 0.0001
Total	n = 164914962	n = 161120804