Skip to main content

Table 2 Geometric mean titers in prefrail and frail subjects, and all study subjects before and 4 weeks after influenza vaccination

From: Influenza vaccine response in community-dwelling German prefrail and frail individuals

Vaccine

 

Prefrail (n = 48)

Frail (n = 25)

All (n = 73)

p value (prefrail vs. frail)

 

GMT

GMSD

Lower

Upper

GMT

GMSD

Lower

Upper

GMT

GMSD

Lower

Upper

 

A/California/7/2009 (H1N1)

Before

27.9

3.7

7.6

102.4

17.9

3.0

6.0

53.7

24.0

3.3

7.2

79.7

 

After

89.8a

3.3

27.0

298.1

84.6a

4.5

18.8

380.7

88.0a

3.7

24.0

322.9

 

Ratio

3.2

   

4.7

   

3.9

   

0.57

A/Texas/50/2012 (H3N2)

Before

37.2

2.7

13.7

101.1

42.3

2.2

19.0

94.1

38.9

2.7

14.3

105.7

 

After

92.4a

3.3

27.8

306.8

84.6a

2.5

34.4

208.1

89.7a

3.0

29.9

269.5

 

Ratio

2.5

   

2.0

   

2.3

   

0.38

B/Massachusetts/2/2012

Before

9.0

2.0

4.5

18.1

9.2

2.2

4.1

20.5

9.1

2.0

4.5

18.3

 

After

17.1a

2.7

6.3

46.5

21.1a

3.3

6.4

70.1

18.4a

3.0

6.1

55.3

 

Ratio

1.9

   

2.3

   

2.0

   

0.38

  1. GMT represents geometric mean for the titer counts and GMSD refers to it’s corresponding standard deviation. The calculation of the confidence interval is by dividing the GMT by the GMSD for the lower bound and multiplying it for the upper bound. "Before" refers to baseline samples (i.e. 4 weeks before vaccination) and "After" refers to 4 weeks after vaccination. aPre-vaccination GMT significantly different from post-vaccination GMT (p < 0.01). The P-values presented here pertain to the comparison of ratios between the prefrail and frail groups. A linear mixed model was used and a logarithmic transformation was applied to the titer counts (before and after) and their difference would result in the before and after ratio. Adjustment for age and BMI were done (as they were found to be significant at baseline demographics level) but no significant difference was observed from the simpler model. Therefore the results presented here are coming from the simpler model