Table 1: Association of HbA1c variability and social demographic and clinical characteristics of patients with diabetes.

Characteristic

Quintile of HbA1c Variability

P value**

Overall

Q1: ≤ 0.12

Q2: > 0.12- ≤ 0.20

Q3: > 0.20- ≤ 0.28

Q4: > 0.28- ≤ 0.45

Q5: > 0.45

N = 4,458

N = 928

N = 799

N = 942

N = 897

N = 892

Age group (years)

 

 

 

 

 

 

< 0.0001

65-74

30.37

26.08

30.16

29.83

28.65

37.33

75-84

51.68

52.91

51.44

52.65

54.63

46.64

≥ 85

17.95

21.01

18.4

17.52

16.72

16.03

Gender

 

 

 

 

 

 

0.0054

Female

54.37

58.08

56.32

55.31

51.62

50.56

Male

45.63

41.92

43.68

44.69

48.38

49.44

Race

 

 

 

 

 

 

0.0813

White

87.01

88.07

85.32

88.2

88.18

85

Non-white

12.99

11.93

14.68

11.8

11.82

15

Median household income quartile

 

 

 

 

 

 

0.193

1st (< $48,683)

26.61

25.92

27.09

25

26.24

28.98

2nd ($48,683-$67,236)

24.73

23.75

25.95

23.93

23.76

26.48

3rd ($67,237-$81,714)

24.23

23.97

23.92

23.93

25.56

23.75

4th (> $81,714)

24.43

26.36

23.04

27.15

24.44

20.8

Education level quartile

 

 

 

 

 

 

0.1118

1st (< 17.3% college or higher)

23.3

20.72

24.68

21.24

23.65

26.59

2nd (17.3%-27.0%)

26

25.16

25.06

26.18

26.24

27.27

3rd (27.1%-43.5%)

25.5

26.25

25.06

26.29

25.68

24.09

4th (> 43.5%)

25.2

27.87

25.19

26.29

24.44

22.05

Product type

 

 

 

 

 

 

0.8045

HMO

95.72

95.8

95.87

95.97

95.99

95.72

PPO

4.28

4.2

4.13

4.03

4.01

4.28

Comorbidities

 

 

 

 

 

 

 

Obesity

15.03

13.05

11.76

14.57

16.42

19.08

0.0002

Tobacco use

8.6

6.36

8.14

8.09

9.5

11

0.0077

Hypertension

90.39

89.32

89.49

91.06

91.17

90.8

0.5148

Hyperlipidemia

86.12

85.87

83.48

86.91

87.04

87.98

0.1718

Ischemic heart disease

11.3

8.41

9.51

9.79

14.41

14.37

< 0.0001

Stroke

15.39

14.35

15.64

15.11

15.75

16.16

0.8493

Anxiety

6.87

5.72

6.38

7.02

7.71

7.52

0.43

Depression

8.29

8.2

6.88

6.38

8.72

11.22

0.002

Chronic kidney disease

22.48

17.15

20.65

21.17

24.13

29.41

< 0.0001

Diabetic complications

 

 

 

 

 

 

 

Diabetic retinopathy

17.45

12.62

13.77

17.55

22.79

20.31

< 0.0001

Diabetic neuropathy

18.31

14.02

15.27

18.72

21.79

21.55

< 0.0001

Diabetic nephropathy

12.83

9.49

11.76

12.23

13.07

17.62

< 0.0001

Modified Charlson comorbidity index

 

 

 

 

 

 

< 0.0001

0

26.68

32.58

30.41

25.43

22.57

22.67

1-2

34.19

35.49

33.67

38.62

30.95

31.87

≥ 3

39.13

31.93

35.92

35.96

46.48

45.45

Emergency department visit

30.62

26.4

27.66

27.71

34.23

37.11

< 0.0001

Number of outpatient visit*

1 (0-3)

1 (0-3)

1 (0-3)

1 (0-3)

2 (0-4)

2 (1-4)

< 0.0001

Any hospitalization

18.89

13.25

14.77

17.73

24.19

24.33

< 0.0001

Number of PCP/internist visit*

9 (5-16)

8 (4-14)

9 (4-14)

9 (5-16)

11 (6-18)

10 (6-18)

0.0134

Endocrinologist visit

19.96

14.22

13.39

19

24.53

28.25

< 0.0001

Nephrologist visit

10.32

7.11

8.01

11.25

11.04

14.01

< 0.0001

Podiatrist

33.15

33.08

29.29

32.06

35.45

35.54

0.0353

Cardiologist

52.65

46.55

53.32

52.55

55.96

55.16

0.0005

Number of specialist visit*

4 (1-9)

3 (1-7)

4 (1-8)

4 (1-8)

5 (2-11)

5 (2-10)

< 0.0001

Ambulance use

44.59

37.93

41.43

43.63

49.61

50.34

< 0.0001

Echography

27.74

23.38

28.54

26.96

32.78

32.62

< 0.0001

EKG

44.24

38.58

47.31

44.48

46.38

44.96

0.0019

Stress test

11.84

8.94

12.64

10.62

13.38

13.9

0.0048

DxCG risk score tertile

 

 

 

 

 

 

< 0.0001

1st (< 3.456)

33.02

37.82

34.29

34.18

29.88

28.81

2nd (3.456-7.172)

33

34.7

35.67

33.76

30.55

30.49

3rd (> 7.172)

33.98

27.48

30.04

32.06

39.58

40.7

Number of distinct generic drug*

10 (7-14)

9 (6-12)

9 (6-13)

10 (7-13)

11 (7-15)

12 (8-16)

< 0.0001

Insulin use

22.75

10.02

13.89

19.43

27.31

42.83

< 0.0001

Statin use

72.97

74.35

72.34

73.35

68

76.68

0.001

Antidiabetic MPR ≥ 80%**

70.1

68.86

69.09

69.85

69.23

73.43

0.1885

Number of HbA1c testing

3 (3-4)

3 (3-3)

3 (3-4)

3 (3-4)

3 (3-4)

3 (3-4)

< 0.0001

Mean HbA1c

6.80 (6.28-7.53)

6.27 (6.00-6.64)

6.48 (6.13-6.88)

6.77 (6.33-7.27)

7.10 (6.60-7.70)

7.87 (7.30-8.73)

< 0.0001

Absolute change in HbA1c

0.1 (-0.2-0.4)

0.0 (-0.1-0.1)

0.1 (-0.1-0.3)

0.2 (-0.3-0.4)

0.1 (-0.6-0.7)

-0.2 (-1.3-1.1)

< 0.0001

HbA1c > 9% in next year

21.89

15.37

15.88

18.14

22.13

28.48

< 0.0001

 

*data presented as median (interquartile range)

** MPR, medication possession ratio was averaged across medication classes for subjects taking medications from more than 1 drug class. Non adherence was defined as MPR < 80%.

***comparisons between values for members among different quintile of HbA1c variability.