Otitis media, tympanostomy tube placement, and use of antibiotics

Figures & data

Table I.  Study population: characteristics of the populations in 2003 and 1998.

Area	Year	Total no. of inhabitants and no. of GP positions within parentheses	Children 1–6 years old No.	Children 1–6 years old invited No.	Participants No.	Participation rate	Mean age of participants (years±SD)
H Hafnarfjordur	1998	18.203 (9.2)	1.989	442	331	75%	4.07±1.75
	2003	20.675 (10.2)	2.004	380	287	76%	4.16±1.65
V Vestmannaeyjar	1998	4.640 (4)	512	321	244	76%	4.20±1.67
	2003	4.416 (4)	406	396	324	82%	4.37±1.57
E Egilsstadir	1998	3.076 (3)	300	198	174	88%	4.04±1.78
	2003	2.874 (3)	265	256	216	84%	4.20±1.71
B Bolungarvik	1998	1.094 (1)	99	66	55	83%	4.23±1.72
	2003	957 (1)	82	75	62	83%	3.89±1.64
Total	1998	27.013 (17.2)	2.900	1.030	804	78%	4.11±1.73
	2003	28.922 (18.2)	2.757	1.107	889	80%	4.22±1.64

Table II.  Total number of antimicrobial treatment courses during the 12 months prior to enrolment, number of treatment courses for AOM, and number (%) of children 1–6 years of age having had tympanostomy tube placement.

Area	Year	No. of treatment courses per child per year (95% CI)	No. of treatment courses for AOM per child per year (95%CI)	No. (%) of children having had tympanostomy tube placement	p-value* for changes in tympanostomy tube placement rate between 1998 and 2003
H	1998	1.16 (0.99–1.33)	0.69 (0.56–0.83)	81/310 (26.1)
	2003	1.05 (0.86–1.23)	0.57 (0.43–0.71)	103/280 (36.8)	0.006
V	1998	1.51 (1.26–1.75)	0.81 (0.62–1.00)	79/227 (34.8)
	2003	1.48 (1.27–1.69)	0.88 (0.71–1.04)	143/324 (44.1)	0.034
E	1998	0.89 (0.60–1.09)	0.57 (0.41–0.74)	39/148 (26.4)
	2003	0.53 (0.41–0.65)	0.27 (0.19–0.36)	37/215 (17.2)	0.049
B	1998	1.15 (0.72–1.57)	0.65 (0.32–0.99)	17/50 (34.0)
	2003	0.72 (0.46–0.98)	0.41 (0.20–0.62)	15/61 (24.6)	0.299
Total	1998	1.21 (1.09–1.32)	0.70 (0.61–0.79)	216/735 (29.4)
	2003	1.06 (0.95–1.16)	0.60 (0.52–0.68)	298/880 (33.9)	0.060

Corresponding figures from the 1998 study are included.

Table III.  Mean number of antimicrobial treatment courses per year for AOM and adjusted odds ratios (OR) for children treated with antimicrobials for AOM in the preceding 12 months (n = 270), as opposed to not (n = 593).

Variable	Mean number of treatment courses per year for AOM (95%CI)	OR	95% CI	p-value
Age
1–3 yrs	1.06 (0.90–1.21)	1
4–6 yrs	0.23 (0.18–0.28)	0.18	0.12–0.25	0.0001
Gender
male	0.61 (0.50–0.72)	1
female	0.59 (0.47–0.70)	1.01	0.73–1.40	0.99
Siblings
No	0.82 (0.57–1.08)	1
Yes	0.55 (0.47–0.63)	0.79	0.52–1.20	0.25
Residence
Area V	0.88 (0.71–1.04)	1
Area E	0.27 (0.19–0.36)	0.32	0.20–0.51	0.0001
Area B	0.41 (0.20–0.62)	0.44	0.22–0.88	0.019
Area H	0.57 (0.43–0.71)	0.50	0.34–0.74	0.0003
Day care
No	0.89 (0.58–1.20)	1
Yes	0.57 (0.49–0.66)	0.86	0.50–1.47	0.56
Tympanostomy tube, now or before
Yes	0.94 (0.75–1.13)	1
No	0.43 (0.36–0.50)	0.49	0.35–0.70	0.0001
Smoking in the house
No	0.59 (0.50–0.68)	1
Yes	0.64 (0.45–0.82)	0.92	0.61–1.41	0.69

Multivariate analysis (863 cases analysed, data missing for 26 cases). Overall significance: chi-square = 165,79, df = 10, p = 0.0000.

Figure 1. Correlation between tympanostomy tube placement rate (cumulative prevalence) and antimicrobial use for acute otitis media (last 12 months) among 1- to 6-year-old children in Iceland, 2003.

Table IV.  Odds ratio (OR) adjusted for age for children having tympanostomy tubes (n = 123), as opposed to not (n = 736).

Variable	No.	OR	95%CI	p-value
Residence
Area V	314	1
Area E	214	0.35	0.17–0.64	0.0021
Area B	61	1.02	0.46–2.24	0.97
Area H	270	0.81	0.50–1.30	0.38
Number of antimicrobial treatments for AOM, last 12 months
0	594	1
1–2	203	1.96	1.22–3.17	0.0059
≥ 3	62	4.98	2.60–9.53	0.0001
Gender
Female	407	1
Male	452	1.28	0.84–1.94	0.25
Smoking in the family house setting
No	701	1
Yes	158	1.01	0.60–1.72	0.95
Day care
No	71	1
Yes	788	2.38	1.07–5.28	0.0317

Multivariate analysis (859 cases analysed, data missing in 30 cases). Overall significance: chi-square = 100.176, df = 9, p = 0.0000.

Table V.  Results from parents’ questionnaires regarding appropriate antimicrobial usage for upper respiratory tract infections for children, number and percentage (%), compared with results from the 1998 study.

Question/area	Year	Always	Sometimes	Never	Don't know
Question 1^1		Is it appropiate to give antimicrobial treatment for acute otitis media?
Area H	1998	27 (8.3)	286 (87.5)	3 (0.9)	11 (3.4)
	2003	30 (10.7)	231 (82.5)	3 (1.1)	16 (5.7)
Area V	1998	28 (11.5)	197 (81.1)	4 (1.6)	14 (5.8)
	2003	33 (10.2)	274 (85.1)	1 (0.3)	14 (4.3)
Area E	1998	9 (5.2)	152 (87.9)	5 (2.9)	7 (4.0)
	2003	11 (5.1)	194 (90.7)	1 (0.5)	8 (3.7)
Area B	1998	2 (3.6)	51 (92.7)	1 (1.8)	1 (1.8)
	2003	1 (1.6)	58 (95.1)	1 (1.6)	1 (1.6)
Total	1998	66 (8.3)	686 (86.0)	13 (1.6)	33 (4.1)
	2003	75 (8.6)	757 (86.3)	6 (0.7)	39 (4.4)
Question 2^2		Is it appropriate to give antimicrobial treatment for unspecified upper respiratory tract infection (common cold)?
Area H	1998	0 (0.0)	154 (47.2)	148 (45.4)	24 (7.4)
	2003	0 (0)	122 (44.0)	137 (49.5)	18 (6.5)
Area V	1998	1 (0.4)	121 (49.8)	95 (39.1)	26 (10.7)
	2003	0 (0)	186 (57.9)	114 (35.5)	21 (6.5)
Area E	1998	0 (0.0)	50 (28.9)	109 (63.0)	14 (8.1)
	2003	0 (0)	64 (30.2)	131 (61.8)	17 (8.0)
Area B	1998	0 (0.0)	21 (38.2)	25 (45.5)	9 (16.4)
	2003	0 (0)	20 (32.8)	38 (62.3)	3 (5.1)
Total	1998	1 (0.1)	346 (43.4)	377 (47.3)	73 (9.2)
	2003	0 (0)	392 (45.0)	420 (48.2)	59 (6.8)

¹1998, Pearson chi-square 13.01, df 9, p = 0.159; 2003, Pearson chi-square 15.05, df 9, p = 0.090. ²1998, Pearson chi-square 32.27, df 9, p = 0.0001; 2003, Pearson chi-square 46.65, df 9, p = 0.0001.