Otitis Media and Speech and Language: A Meta-analysis of Prospective Studies

Objective. Considerable controversy surrounds whether a history of otitis media with effusion (OME) in early childhood causes later speech and language problems. We conducted a meta-analysis of prospective studies to determine: 1) whether a history of OME in early childhood is related to receptive language, expressive language, vocabulary, syntax, or speech development in children 1 to 5 years old and 2) whether hearing loss caused by otitis media in early childhood is related to children’s receptive language or expressive language through 2 years of age. Methods. We searched online databases and bibliographies of OME studies and reviews for prospective or randomized clinical trials published between January 1966 and October 2002 that examined the relationship of OME or OME-associated hearing loss in early childhood to children’s later speech and language development. The original search identified 38 studies, of which 14 had data suitable for calculating a pooled correlation coefficient (correlational studies) or standard difference between parallel groups (group studies). Random-effects meta-analysis was used to pool data when at least 3 studies had usable data for a particular outcome. Results. We performed 11 meta-analyses. There were no significant findings for the analyses of OME during early childhood versus receptive or expressive language during the preschool years in the correlation studies. Similarly, there were no significant findings for OME versus vocabulary, syntax, or speech during the preschool years. Conversely, there was a significant negative association between OME and preschoolers’ receptive and expressive language (lower language) (0.24 and 0.25 standard difference, respectively) in the group studies. Additionally, hearing was also related to receptive and expressive language in infancy (3%–9% of variance). Conclusions. Our results indicate no to very small negative associations of OME and associated hearing loss to children’s later speech and language development. These findings may overestimate the impact of OME on outcomes, because most studies did not adjust for known confounding variables (such as socioeconomic status) and excluded data not suitable for statistical pooling, especially from methodologically sound studies. Although some OME language differences were detectable by meta-analysis due to increased statistical power, the clinical relevance for otherwise healthy children is uncertain. Pediatrics 2004;113:e238 –e248. URL: http: //www.pediatrics.org/cgi/content/full/113/3/e238; otitis media, childhood, meta-analysis, speech, language. ABBREVIATIONS. OM, otitis media; OME, otitis media with effusion; RCT, randomized clinical trial; AHRQ, Agency for Healthcare Research and Quality; SD, standard deviation; PPVT, Peabody Picture Vocabulary Test; NDW, number of different words; MLU, mean length of utterance; CI, confidence interval; SES, socioeconomic status; d, standard difference; ANOVA, analysis of variance; PLS, Preschool Language Scale; SICD, Sequenced Inventory of Communication Development; RDLS, Reynell Development Language Scales; PCC, percent consonants correct. There continues to be considerable debate over whether a history of otitis media (OM) with effusion (OME) during the first few years of life, a critical period for learning language, causes later speech and language difficulties.1–3 When a child has OME, a mild to moderate fluctuating hearing loss generally occurs that has been hypothesized to interfere with rapid language processing, causing a child to encode information inefficiently, incompletely, or inaccurately into the database from which language develops.3 If OME and the associated hearing loss persists or recurs during the formative years of language and learning, it has been hypothesized to delay language development, possibly affecting vocabulary or grammar. During the past 3 decades, 100 original studies have examined whether a history of OM (including OME and acute OM) is related to later speech and language development. Children with a history of OME scored lower on measures of speech and language development in some studies,4–6 compared with children who infrequently experienced OME, whereas other studies did not find such a linkage between OME and children’s speech and language development.7–9 Although earlier studies10,11 of the OME-language learning relationship had many methodologic problems, studies in the past 2 decades avoided many of these problems by following children prospectively7,12,13 or using randomized clinical trials (RCTs) in which children with persistent OME were randomized to have tympanostomy tubes inserted promptly or at a later point while monitoring language development.6,8,9 Two recent systematic reviews14,15 examined how OME relates to children’s later speech and language development. The Agency for Healthcare Research and Quality (AHRQ)14 examined associations between a history of OME and standardized measures From the *Frank Porter Graham Child Development Institute, University of North Carolina, Chapel Hill, North Carolina; and ‡State University of New York, Downstate Medical Center, and Long Island College Hospital, Brooklyn, NY. Received for publication Apr 4, 2003; accepted Nov 24, 2003. Reprint requests to (J.E.R.) Frank Porter Graham Child Development Institute, University of North Carolina, 105 Smith Level Rd, CB 8180, Chapel Hill, NC 27599-8180. E-mail: joanne [email protected] PEDIATRICS (ISSN 0031 4005). Copyright © 2004 by the American Academy of Pediatrics. e238 PEDIATRICS Vol. 113 No. 3 March 2004 http://www.pediatrics.org/cgi/content/full/113/3/e238 by guest on July 20, 2017 Downloaded from T A B L E 1. C ha ra ct er is ti cs of Fi na l D at a Se t fo r M et aA na ly si s A ut ho r (Y ea r) an d L oc at io n D es cr ip ti on of St ud y Sa m pl e: So ur ce ;E th ni ci ty ;S E S O M E an d H ea ri ng D oc um en ta ti on M et aA na ly se s U si ng St ud y D at a (T es t U se d ,C hi ld A ge at T es ti ng ) T ee le et al 46 (1 98 4) B os to n, M A N ei gh bo rh oo d he al th ce nt er s an d pr iv at e pr ac ti ce ; et hn ic it y un kn ow n; SE S: m id d le an d lo w er O to sc op y, ag e 0– 3 y (w el l an d si ck of fi ce vi si ts ) C or re la ti on al an al ys es : R ec la ng ua ge 3 y vs O M E (P L S, 3 y) E xp la ng ua ge 3 y vs O M E (P L S, 3 y) V oc ab ul ar y 3 y vs O M E (P PV T ,3 y) O M gr ou p vs O M gr ou p an al ys es : R ec la ng ua ge 2– 5 y vs O M E (P L S, 3 y) E xp la ng ua ge 2– 5 y vs O M E (P L S, 3 y) V oc ab ul ar y 3 y vs O M E (P PV T ,3 y) Pe ar ce et al 42 (1 98 8) A lb er ta ,C an ad a H os pi ta l, 37 w ee ks ’ ge st at io n an d 15 00 g or co m pl ic at ed ve nt ila ti on ;I Q 70 ;O M ha d tu be s be fo re ag e 3. 5 y or ab no rm al ty m p tw ic e; O M ha d no rm al ty m p; 88 % w hi te ;S E S: un kn ow n T ym p at 0, 4, 8, 12 ,1 8, an d 36 m o O M gr ou p vs O M gr ou p an al ys es : R ec la ng ua ge 2– 5 y vs O M E (S IC D ,2 –4 y) R ac h et al 43 (1 98 8) N ijm eg en ,N et he rl an d s C om m un it y bi rt h co ho rt ,m at ch ed sa m pl e; O M ha d O M E 6 m o; O M w as no rm al ;S E S: un kn ow n; D ut ch sp ea ki ng T ym p ev er y 3 m o, ag e 2– 4 y O M gr ou p vs O M gr ou p an al ys es : R ec la ng ua ge 2– 5 y vs O M E (R D L S, 31 –3 6 m o) E xp la ng ua ge 2– 5 y vs O M E (R D L S, 31 –3 6 m o) W al la ce et al 47 (1 98 8) N ew Y or k, N Y H os pi ta l, hi gh -r is k an d fu llte rm in fa nt s; 52 % H is pa ni c, 44 % bl ac k; SE S: m os tl y lo w ;E ng lis h sp ea ki ng O to sc op y, ag e 0– 1 y (m ea n 8– 9 vi si ts ); A B R at 0, 3, 6, 9, an d 12 m o C or re la ti on al an al ys es : R ec la ng ua ge 1– 2 y vs he ar in g (S IC D ,1 y) E xp la ng ua ge 1– 2 y vs he ar in g (S IC D ,1 y) Fr ie lPa tt i an d Fi ni tz o 4 0 (1 99 0) D al la s, T X Pr iv at e pe d ia tr ic pr ac ti ce ,t yp ic al ly d ev el op in g; et hn ic it y un kn ow n; SE S m id d le -h ig h; E ng lis h sp ea ki ng O to sc op y, ty m p ev er y 6 w ee ks ,a ge 6– 18 m o, th en ev er y 12 w ee ks C or re la ti on al an al ys es : R ec la ng ua ge 1– 2 y vs he ar in g (S IC D ,1 8 m o) E xp la ng ua ge 1– 2 y vs he ar in g (S IC D ,1 8 m o) R ob er ts et al 44 (1 99 1) N or th C ar ol in a A B C St ud y U ni ve rs it yba se d ch ild ca re ;6 0% bl ac k, 38 % w hi te ; SE S: 52 % lo w ,4 8% m id d le O to sc op y, ty m p ev er y 2– 4 w ee ks ,a ge 0– 3 y C or re la ti on al an al ys es : V oc ab ul ar y 3– 5 y vs O M E (N D W ,5 4 m o) Sy nt ax 3– 5 y vs O M E (M L U ,5 4 m o) G ra ve l an d W al la ce 41 (1 99 2) N ew Y or k, N Y H os pi ta l, 61 % hi gh ri sk ,3 9% fu ll te rm in fa nt s; 52 % bl ac k, 39 % H is pa ni c; SE S: lo w ;E ng lis h sp ea ki ng O to sc op y, 0– 1 y (1 0 ro ut in e vi si ts pl us ill ne ss vi si ts ) O M gr ou p vs O M gr ou p an al ys es : R ec la ng ua ge 2– 5 y vs O M E (S IC D ,4 y) E xp la ng ua ge 2– 5 y vs O M E (S IC D ,4 y) R ob er ts et al 45 (1 99 8) N or th C ar ol in a C O M P St ud y C hi ld ca re ce nt er s; 10 0% bl ac k; SE S: m os tl y lo w O to sc op y, ty m p ev er y 2– 4 w ee ks ,a ge 6– 24 m o C or re la ti on al an al ys es : R ec la ng ua ge 1– 2 y vs he ar in g (S IC D -R ,2 y) E xp la ng ua ge 1– 2 y vs he ar in g (S IC D -R ,2 y) M aw et al 6 (1 99 9) B ri st ol ,U ni te d K in gd om O to la ry ng ol og y cl in ic ;i f bi la te ra l ch ro ni c O M E ra nd om iz ed to no tu be s (O M ) vs tu be s (O M ); 96 % w hi te ;S E S: un kn ow n O to sc op y, ty m p; bi la te ra l O M E d oc um en te d 3 m o O M gr ou p vs O M gr ou p an al ys es : R ec la ng ua ge 2– 5 y vs O M E (R D L S, 3. 8– 4. 5 y) E xp la ng ua ge 2– 5 y vs O M E (R D L S, 3. 8– 4. 5 y) Pa ra d is e et al 7 (2 00 0) Pi tt sb ur gh ,P A U rb an ho sp it al s or pr iv at e pr ac ti ce ;8 3% w hi te ,1 6% bl ac k; SE S: 32 % lo w ,6 6% pr iv at e in su ra nc e O to sc op y, ty m p at le as t m on th ly ,a ge 0– 3 y C or re la ti on al an al ys es : V oc ab ul ar y 3 y vs O M E (P PV T -R ,3 y) V oc ab ul ar y 3– 5 y vs O M E (N D W ,3 y) Sy nt ax 3 y vs O M E (M L U ,3 y) O M gr ou p vs O M gr ou p an al ys es : V oc ab ul ar y 3 y vs O M E (P PV T -R ,3 y) Sp ee ch 3 y vs O M E (P C C ,3 y) R ob er ts et al 12 (2 00 0) N or th C ar ol in a C O M P St ud y C hi ld ca re ce nt er s; 10 0% bl ac k; SE S: m os tl y lo w O to sc op y, ty m p ev er y 2– 4 w ee ks ,a ge 6– 48 m o C or re la ti on al an al ys es : R ec la ng ua ge 3 y vs O M E (S IC D -R ,3 y) E xp la ng ua ge 3 y vs O M E (S IC D -R ,3 y) V oc ab ul ar y 3 y vs O M E (P PV T ,3 y) V oc ab ul ar y 3– 5 y vs O M E (N D W ,3 y) Sy nt ax vs 3– 5 y O M E (M L U ,3 –5 y) R ov er s et al 9 (2 00 0) U tr ec ht ,N et he rl an d s B ir th co ho rt fa ile d he ar in g sc re en ag e 9 m o; if O M E 4– 6 m o ra nd om iz ed to no tu be s (O M ) vs tu be s (O M ); SE S: un kn ow n O to sc op y, ty m p, au d io gr am ev er y 3 m o, ag e 9– 19 m o O M gr ou p vs O M gr ou p an al ys es : R ec la ng ua ge 2– 5 y vs O M E (R D L S, 2. 5 y) E xp la ng ua ge 2– 5 y vs O M E (R D L S, 2. 5 y) http://www.pediatrics.org/cgi/content/full/113/3/e238 e239 by guest on July 20, 2017 Downloaded from of receptive and expressive language in 6 cohorts of children and concluded that they could neither support nor refute the possible effect of OME on children’s language development. Casby15 analyzed 22 studies of the association of OME to children’s receptive and expressive language, combining multiple outcomes from single-cohort, group, and correlation studies, different ages, and specific and overall measures of language. He reported the magnitude of an association of OME to language to be markedly low. OME-related hearing loss was not used as a predictor in either of these meta-analyses. The conclusions and the meta-analyses, however, may have limited validity because of issues concerning study selection, data pooling, and choice of outcome measures. To address the methodologic limitations of earlier systematic reviews, we conducted a meta-analysis to test whether a history of OME in early childhood is related to children’s later speech and language skills. We included only prospective studies and RCTs because they provide the highest scientific rigor for clinical recommendations.16 We examined the following speech and language outcomes separately in children tested between 1 and 5 years of age: 1) receptive language or language comprehension; 2) expressive language or language production; 3) speech production or how the individual sounds are said; and 4) 2 commonly studied language domains (vocabulary and grammar). We initially included studies of children through the age of 12 years but found insufficient combinable data to complete analyses after age 5 years. We also examined OMErelated hearing loss as a predictor of language outcomes when there was sufficient data for the analysis.