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Table 4 Univariate and multivariate analysis of factors associated with sputum S. pneumoniae and S. aureus colonisation

From: Prevalence and antimicrobial resistance profiles of respiratory microbial flora in African children with HIV-associated chronic lung disease

Variable

No. observations (n = 400) §

Streptococcus pneumoniae

Staphylococcus aureus

No. isolates (n = 100)φ

OR [95% CI]

p

Adjusted OR [95% CI]

p

No. isolates (n = 114)λ

OR [95% CI]

p

Adjusted OR [95% CI]

p

Group

 CLD-

18% (74)

17% (17)

Reference

 

Reference

 

18% (21)

Reference

 

Reference

 

 CLD+

82% (326)

83% (83)

1.2 [0.6–2.1]

0.66

1.3 [0.6–2.6]

0.52

82% (93)

1.0 [0.6–1.8]

0.98

1.0 [0.5–1.8]

0.92

Study site

 Malawi

27% (108)

13% (13)

Reference

 

Reference

 

18% (21)

Reference

 

Reference

 

 Zimbabwe

73% (292)

87% (87)

3.1 [1.7–6.1]

<0.001

3.1 [1.4–7.3]

0.01

82% (93)

1.9 [1.2–3.4]

0.02

2.1 [1.1–4.2]

0.04

Sex

 Female

52% (207)

52% (52)

Reference

 

Reference

 

50% (57)

Reference

 

Reference

 

 Male

48% (193)

48% (48)

1 [0.6–1.6]

0.95

0.9 [0.6–1.5]

0.73

50% (57)

1.1 [0.7–1.7]

0.66

1.1 [0.7–1.8]

0.57

Season of sample collection

 Dec–Apr - Rainy

36% (143)

26% (26)

Reference

 

Reference

 

32% (37)

Reference

 

Reference

 

 May–Aug - Cool

39% (157)

41% (41)

1.6 [0.9–2.8]

0.03

1.6 [0.9–3.0]

0.04

37% (42)

1.1 [0.6–1.8]

0.25

1.1 [0.6–1.8]

0.27

 Sep–Nov - Hot

25% (100)

33% (33)

2.2 [1.2–4.1]

2.3 [1.2–4.4]

31% (35)

1.5 [0.9–2.7]

1.6 [0.9–2.8]

Enrolment age category

 17-19y

33% (130)

38% (38)

Reference

 

Reference

 

39% (45)

Reference

 

Reference

 

 13-16y

40% (161)

39% (39)

0.8 [0.5–1.3]

0.34

0.8 [0.5–1.4]

0.38

38% (43)

0.7 [0.4–1.1]

0.15

0.7 [0.4–1.2]

0.25

 6-12y

27% (109)

23% (23)

0.7 [0.4–1.2]

0.6 [0.3–1.2]

23% (26)

0.6 [0.3–1.0]

0.6 [0.3–1.1]

Number of years on ART

 6 m- < 2y

9% (35)

12% (12)

Reference

 

Reference

 

9% (10)

Reference

 

Reference

 

 2- < 4y

18% (71)

21% (21)

0.8 [0.3–1.9]

0.39

0.6 [0.2–1.5]

0.04

17% (19)

0.9 [0.4–2.3]

0.83

0.7 [0.3–1.8]

0.57

 4y- < 6y

20% (79)

19% (19)

0.6 [0.3–1.5]

0.4 [0.2–1.0]

23% (26)

1.2 [0.5–3.0]

0.9 [0.4–2.4]

 6y+

53% (208)

47% (47)

0.6 [0.3–1.2]

0.3 [0.1–0.8]

51% (58)

1 [0.5–2.2]

0.6 [0.3–1.6]

CD4 count

  > 500

63% (251)

63% (63)

Reference

   

59% (67)

Reference

   

 200–500

28% (110)

26% (26)

0.9 [0.5–1.6]

0.81

  

32% (36)

1.3 [0.8–2.2]

0.51

  

  < 200

10% (38)

11% (11)

1.2 [0.6–2.5]

  

10% (11)

1.1 [0.5–2.3]

  

Enrolment viral load

 Unsuppressed

42% (169)

35% (35)

Reference

   

47% (54)

Reference

 

Reference

 

 Suppressed

58% (231)

65% (65)

1.5 [0.9–2.4]

0.09

1.4 [0.8–2.3]

0.22

53% (60)

0.8 [0.5–1.2]

0.19

0.7 [0.4–1.1]

0.09

ART regimen

 PI-based regimen - 2nd line

24% (98)

27% (27)

Reference

 

Reference

 

25% (28)

Reference

 

Reference

 

 NNRTI-based regimen -1st line

76% (302)

73% (73)

0.9 [0.5–1.5]

0.57

1.1 [0.6–2.1]

0.75

75% (86)

1 [0.6–1.7]

0.947

1.2 [0.7–2.2]

0.54

Ever treated for TB

 No

74% (294)

65% (65)

Reference

 

Reference

 

72% (82)

Reference

 

Reference

 

 Yes

26% (104)

35% (35)

1.8 [1.1–2.9]

0.02

1.8 [1.0–3.2]

0.04

28% (32)

1.2 [0.7–1.9]

0.58

1.0 [0.6–1.8]

0.92

Enrolment weight- for-age- z-score

 Not underweight

54% (217)

61% (61)

Reference

   

54% (61)

Reference

   

 Underweight

46% (183)

39% (39)

0.7 [0.4–1.1]

0.12

  

46% (53)

1.0 [0.7–1.6]

0.85

  

Enrolment height-for-age- z-score -

 Not stunted

55% (218)

59% (59)

Reference

 

Reference

 

58% (66)

Reference

 

Reference

 

 Stunted

46% (182)

41% (41)

0.8 [0.5–1.2]

0.3

0.9 [0.5–1.5]

0.64

42% (48)

0.8 [0.5–1.3]

0.39

0.8 [0.5–1.3]

0.46

Ever repeated a grade

 No

46% (180)

49% (49)

Reference

   

47% (54)

Reference

   

 Yes

54% (211)

51% (50)

0.8 [0.5–1.3]

0.43

  

53% (60)

0.9 [0.6–1.4]

0.74

  

MRC dyspnoea score

 1 or 0

60% (240)

68% (67)

Reference

 

Reference

 

65% (73)

Reference

 

Reference

 

  > 1

40% (159)

32% (32)

0.7 [0.4–1.0]

0.079

0.9 [0.5–1.7]

0.86

35% (40)

0.8 [0.5–1.2]

0.25

1.1 [0.6–2.0]

0.67

  1. § Missing values: Number of years on ART (7), CD4 count (1), Ever treated for TB (2), Ever repeated a grade (9) and MRC dyspnoea score (1). φ n = 99 for the number of years on ART, ever repeated a grade, MRC dyspnoea score. λn = 113 for the number of years on ART and MRC dyspnoea score. Variables with two levels where a level is less than 10% of total observations were not tested for associations. These included current school attendance and taking cotrimoxazole. Variables that have values in the adjusted odd ratios column were included in the multivariate model for that bacteria. Variables with p values <0.25 were included in the multivariate model except where they were colinear with another variable within the model. Weight-for-age was colinear with height-for-age and hence excluded from the model. Ever repeated a grade was excluded because of co-linearity with MRC score. CD4 count is colinear with viral load suppression. Clinically relevant variables (a priori-defined) that were included in the multivariate model regardless of significance were group, age, sex, site, season of sample collection, number of years on ART, enrolment viral load, ART regimen, ever treated for TB, enrolment height-for-age z-score and MRC dyspnoea score
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BMC Infectious Diseases

ISSN: 1471-2334

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