Table 1. Hemoglobin A1c (HbA1c) Levels in Participants Reported as Having Diabetes (NHANES 2007-2008 Through 2013-2014)a.
| Participants, Weighted % (95% CI) by NHANES Period | P Value for Trend | ||||
|---|---|---|---|---|---|
| 2007-2008 (n = 757) |
2009-2010 (n = 725) |
2011-2012 (n = 704) |
2013-2014 (n = 722) |
||
| HbA1c level, median (IQR), % | 6.90 (6.20-8.15) | 6.90 (6.20-7.80) | 6.90 (6.30-6.80) | 6.95 (6.30-8.20) | .39 |
| With HbA1c >9% (poor glycemic control) | |||||
| Overall | 13.68 (11.50-15.85) | 11.31 (8.74-13.87) | 16.1 (12.37-19.82) | 14.98 (11.78-18.17) | .99 |
| Age range, y | |||||
| 20-44 | 22 (9.96-34.03) | 27.46 (14.36-40.55) | 32.34 (15.81-48.86) | 19.76 (9.02-30.50) | .56 |
| 45-65 | 15.92 (12.74-19.09) | 12.24 (9.67-14.80) | 16.21 (12.13-20.28) | 19.11 (15.24-22.97) | .91 |
| >65 | 8.18 (5.26-11.10) | 5.51 (3.24-7.78) | 10.49 (6.550-14.42) | 8.00 (4.40-11.61) | .63 |
| Raceb | |||||
| White | 12.14 (9.20-15.07) | 6.66 (4.74-8.58) | 12.02 (7.79-16.25) | 11.94 (7.88-15.99) | .17 |
| Nonwhite | 16.53 (13.41-19.64) | 18.3 (14.10-22.49) | 22.03 (17.71-26.34) | 20.27 (16.27-24.26) | .71 |
| Sex | |||||
| Men | 14.38 (9.58-19.18) | 13.71 (9.97-17.45) | 15.86 (9.69-22.03) | 15.08 (10.90-19.25) | .95 |
| Women | 13.04 (10.45-15.62) | 8.78 (5.39-12.17) | 16.35 (11.48-21.21) | 14.88 (9.7-19.99) | .28 |
| With HbA1c <8% (moderate glycemic control) | |||||
| Overall | 77.27 (73.38-81.15) | 81.05 (76.54-85.55) | 71.14 (65.78-76.49) | 73.32 (69.53-77.10) | .47 |
| Age range, y | |||||
| 20-44 | 64.23 (49.94-78.51) | 61.09 (46.35-75.82) | 56.09 (38.64-73.53) | 72.48 (62.36-82.59) | .39 |
| 45-65 | 74.05 (68.62-79.47) | 80.74 (74.62-86.85) | 65.78 (57.37-74.18) | 68.03 (62.48-73.57) | .16 |
| >65 | 85.5 (81.79-89.20) | 87.33 (83.76-90.89) | 82.73 (76.88-88.57) | 80.33 (74.58-86.07) | .67 |
| Raceb | |||||
| White | 79.1 (74.65-83.54) | 84.88 (79.21-90.54) | 74.1 (66.45-81.74) | 75.43 (70.15-80.70) | .19 |
| Nonwhite | 73.87 (67.61-80.12) | 75.3 (69.61-80.98) | 66.84 (59.52-74.15) | 69.64 (65.36-73.91) | .69 |
| Sex | |||||
| Men | 74.74 (67.72-81.75) | 77.55 (71.59-83.50) | 72.49 (64.59-80.38) | 71.67 (66.22-77.11) | .89 |
| Women | 79.57 (75.78-83.35) | 84.74 (80.01-89.46) | 69.79 (65.47-74.10) | 74.91 (69.77-80.04) | .08 |
| With HbA1c <7% (good glycemic control) | |||||
| Overall | 55.24 (49.24-61.23) | 57.21 (50.89-63.52) | 54.67 (49.59-59.74) | 54.42 (49.87-58.96) | .99 |
| Age range, y | |||||
| 20-44 | 51.91 (35.05-68.76) | 44.38 (26.25-62.50) | 43.58 (24.54-62.61) | 52.12 (40.81-63.42) | .39 |
| 45-65 | 53.03 (45.58-60.47) | 55.27 (45.99-64.54) | 49.88 (43.94-55.81) | 50.5 (44.20-56.79) | .95 |
| >65 | 59.07 (49.62-68.51) | 63.09 (57.62-68.55) | 64.23 (56.76-71.69) | 60.23 (52.05-68.40) | .81 |
| Raceb | |||||
| White | 55.83 (48.57-63.08) | 59.6 (51.97-67.22) | 59.69 (52.71-66.66) | 55.86 (49.60-62.11) | .90 |
| Nonwhite | 54.15 (47.32-60.97) | 53.61 (43.77-63.44) | 47.38 (41.75-53.00) | 51.91 (47.53-56.28) | .86 |
| Sex | |||||
| Men | 55.21 (47.27-63.14) | 55.84 (46.00-65.67) | 53.47 (46.41-60.52) | 51.04 (45.49-56.58) | .29 |
| Women | 55.27 (47.56-62.97) | 58.65 (52.12-65.17) | 55.86 (49.58-62.13) | 57.67 (52.14-63.19) | .27 |
Abbreviations: IQR, interquartile range; NHANES, National Health and Nutrition Examination Survey.
a
Number of participants is unweighted. Survey weights for each period were used to calculate the proportions. We used weights specific to laboratory tests to calculate the values.
b
Race was examined as a subgroup for analysis assuming an association between HbA1c test or target awareness and race. Participants self-reported race and ethnicity by categories defined in NHANES; for this study, race was classified as nonwhite (Mexican American, other Hispanic, non-Hispanic black, other race, including multiracial in the original questionnaire) and white (non-Hispanic white in the original questionnaire).