Table 1 Sociodemographic characteristics, morbidities and ANA distributions of the study groups (%)

Sex

0.168

 Male

48.2

45.2

39.1

47.9

47.2

38.9

43.8

 Female

51.8

54.8

60.9

52.1

52.8

61.1

56.2

Median age (IQR)

55 (47–63)

54 (41–62)

41 (34–50)

48 (30–62)

52 (43–62)

45 (31–59)

<0.0001^b

49 (38–60)

Country of birth

<0.0001

 Germany

83.5

83.8

21.3

88.7

87.7

40.9

64.0

 Other

16.5

16.3

78.7

11.3

12.3

59.1

36.0

BMI

<0.0001

 Underweight (<18.50 kg/m²)

0

1.2

0.4

1.7

2.8

2.6

1.3

 Normal weight (18.50–24.99 kg/m²)

33.8

43.2

18.5

51.1

46.2

46.9

38.7

 Overweight (25.00–29.99 kg/m²)

46.8

39.0

39.9

32.5

35.8

31.3

37.3

 Obesity (≥30.00 kg/m²)

19.4

16.6

41.3

14.8

15.1

19.3

22.7

Heart attack

0.18

 Yes

5.0

0.8

2.3

1.7

2.8

2.6

2.3

 No

95.0

99.2

97.7

98.3

97.2

97.4

97.7

Diabetes

0.40

 Yes

7.2

5.4

9.9

5.9

4.7

6.8

6.8

 No

92.8

94.6

90.1

94.1

95.3

93.2

93.2

ANA positivity

0.742

 Negative (<1:80)

67.6

63.9

66.8

65.1

71.7

68.8

66.7

 Positive (≥1:80)

32.4

36.1

33.2

34.9

28.3

31.3

33.3

ANA positivity

0.157

 Negative (<1:80)

67.6

63.9

66.8

65.1

71.7

68.8

66.7

 Weakly positive (1:80 & 1:160)

25.2

29.0

29.6

32.4

26.4

25.5

28.6

 Moderately positive (1:320 & 1:640)

3.6

5.8

2.5

1.3

1.9

4.7

3.3

 Strongly positive (≥1:1280)

3.6

1.2

1.1

1.3

0

1.0

1.3