Sudden infant death syndrome risk factors: Prospective data review

TY - JOUR

T1 - Sudden infant death syndrome risk factors

T2 - Prospective data review

AU - Lewak, Norman

AU - Van Den Berg, Bea J.

AU - Beckwith, J. Bruce

N1 - Funding Information: Prospective data from a population of newborn infants were searched for risk factors for Sudden Infant Death Syndrome (SIDS). Maternal smoking, younger maternal age, short intervals between pregnancies, gestational age of less than 40 weeks, birth weight of less than 3000 g, lower socioeconomic status and male sex were factors found to be associated with SIDS. Race, blood type, maternal hemoglobin level, placental abnormality and newborn condition were not associated with SIDS in this population. Scoring systems to predict which infants will die of SIDS are not yet sensitive enough for clinical use. sagemeta-type Other search-text 404 SidsSudden Infant Death Syndrome Risk FactorsProspective Data Review SAGE Publications, Inc.1979DOI: 10.1177/000992287901800704 NormanLewak Alameda Pediatric Associates, Alameda, California Bea J.van den Berg Alameda Pediatric Associates, Alameda, California J. BruceBeckwith Alameda Pediatric Associates, Alameda, California Supported in part by grant no. HD-07256 of the Na tional Institute of Child Health and Human Development. Correspondence to: Norman Lewak, M.D., 2219 Santa Clara Avenue, Alameda, CA 94501. Received for publication November, 1978; revised and accepted February, 1979. Prospective data from a population of newborn infants were searched for risk factors for Sudden Infant Death Syndrome (SIDS). Maternal smoking, younger maternal age, short intervals between pregnancies, gestational age of less than 40 weeks, birth weight of less than 3000 g, lower socioeconomic status and male sex were factors found to be associated with SIDS. Race, blood type, maternal hemoglobin level, placental abnormality and newborn condition were not associated with SIDS in this population. Scoring systems to predict which infants will die of SIDS are not yet sensitive enough for clinical use. ARE some infants more MMy to die of the Sudden Infant I~~~~~ Syndrome (SIDS) than others? If ~e~~ can they be identified? SIDS is said to occur more commonly. in infants who are premature. black and in tower socioeconomic groups.' Some authors~,3 have theorized that risk factors for. SIDS can be identified at ~irth. ... " This study was institutedto search for SIDS risk factors in a known newborn population. '..' Methods '. :.. ~ '' . / .. ~ .."" ' ~ ' '~t~~ lPs~pu~~s~~er~ .; '~;~ ~' , ' :...;; The Child~ Health and Development Stud- ies, (CHDS) is a longitudinal research project . relating to, the health, growth and develop- ~ .~ .- rr~entofin,f-antsz,-nd,,chile,.~ren-4 ... :' Kaiser Foundation Plan members in the Oakland area who presented themselves for prenatal care between, 1960 and 1967 were enrolled in the study. The study population is ethnically and socioeconomi- cally broadly based. About 65 per cent of the mothers were white, 24 per. cent Mack, four per cent Oriental, four per cent Mexican- American, and three per cent. were of other ethnic background- ': : ' .:. ' '' . '. : The registered. pregnancies resulted in '19,047. liveborn infants. ;~Y":' /. " /.'\ ~ .' ' ;,:', ~ ~ Data about the mothers' fertility history, health ~~' the .family, and socioeconomic back- ground '.w~Tc'gathered~ ~~~~~~~ ~~~~~~~~~. The medical records, were .abstracted to ob- . tai,n information on the course of pregnancy : and dtlivery. :~: / :':;''',./...''.'''' '~~-\ ,~- "'. ' ..': The medical records of the children' were : abstracted after each medical contact. Exten- /.sivc 'ϵS'orts'...were made to. follow each child, including tmce '~~ ~~~ fami,ly through ~~-~ pa~r~~~~~ ~~ ~~~~.~~° '~~h~~~~ registrations and searching of vital statistics records when necessary. '~' ''~'~.~'.~ /;'"" ~ ~ ''''~ ~,. :~' ~' ~"\' ~ '~' '~:~'': '~; ;~;: ;.~.r ; - Because of these efforts, the status of the .' 405 infants through at least the first year of life is known for 18,999 of the 19,047 infants. Of the 48 lost to follow-up, 13 were followed for at least six months. Since the number of "lost to follow-up" infants is small, the entire CHDS population was used to calculate risk statistics. Procedure The medical histories of all infants who died in the CHDS population were reviewed. Two hundred eighty seven infants died during the initial nursery stay. Of the 76 children who left the nursery alive but died before they were one-year-old,* 41 definite and three possible SIDS deaths were identified using previously defined criteria. 5 Forty-nine possible risk factors were analyzed in two groups: the 44 SIDS infants and a non-SIDS control group- consisting of the 18,716 infants who were discharged alive from the nursery but did not die of SIDS. The data were analyzed using the chi-square method with a Yates correction and expressed as the equivalent p value. Results . Description of SIDS group The 44 SIDS deaths among 19,047 live / born infants amounts to 2.3 deaths per 1,000 live births. This incidence figure and the age / distribution of the SIDS infants (Table I) are .. ; ' similar to previously reported studies.' ~' ~ ~ Genetic factors . "...~.;...'.... " -. .,.':..,., The racial distribution was the same in both the 5~~~ and control groups. In the SIDS group, 20.5 'per cent'..of'tn'e.'.m.o.t.hers.:..were".....:.- '. ~ black, 70.5 per cent were white, and nine ..~~~y.'eϵ~t~we~~other~rac@s..~T~~~~ non-SIDS, group, 23.1 per cent were: .:~taϵ~~N: 615.4 per ~~n~ ~r~~r ~ ~~~~~t~~ ~~a~ i: i 4,~ ~~~ ~~~ ~ other. ' Blood qy§§ was alk the same for both groups. . A blood,< type was recorded for of the 44 ~: ~; SIDS infants . and ' 1 4,860 of the 1,8,7 t6l' non- SIDS one--s'. Of, the, 37 SIPS infants, 1 3.s' per TABLE I.,4ge at Death ~~ 4~ ~SIDS /~M~* *This age distribution is the one found in all SIDS sLU~Iies. ~ I cent were type B, 43.2 per cent were type A, 43.2 per cent were type 0 and none were type AB. In the centred group, 14.4 per cent were type B, 35.9 per cent were type A, 45.8 per cent were type and 3.9 per cent were AB. ~~~ac~~~~~~~~~ factors Blue collar fatherst represented 73.5 per cent of the SIDS group and ~9:~' per cent of the nc~n-~~~~ group (p <.01). More of the SIDS mothers than the controls were ~c~iz~~~~~~~~, 78.5 per cent versus. ~D7.2 per cent., but this was not ,statistically significant, nor was the. difference: in,educational levels of the parents for:the,two groups. ~~~e~~~!' ~~~~~~~ ~`~~#~ ~~ :. ::.: . ' . ' The, SIDS mothers ~weTe.'.signihcantly' . youn Iger and had shorter intervals since their. preceding p~`~~~~~r~~~~~.' Although fewer of '' ' the SIDS pregnancies had been planned and, ' more of the SIDS mothers had one or more pre Ivious pregnancies, neither of these factors "; 'was statistically significant. ..~.':;~\'.'.~;':-~.;. '..:,'\:~ ..'.. ~ ~r~~~.~~~~ ~~n~~i~~ ~durmg-.prcgBanEy~ was . strongly ~ssQciatϵd..;wtt.h.~SID'S.~.( (Smoking'by ~~ine~&t.he~~HdY'ai.CQhn!~ consumption of the,, ' J ~c~~~~~ ~~ ~~.~~~~ ~ no't ~related ~~ -~~~~ .;: ~~~~ ~~~~a~~~ ~~~~~ ~'~~~~~° p~~~.~.~~~ ~~~~~s than' tlie, pr ~ti 'o,,ti Yiiakin' g, less ti-4a~n '~ I ~ ~ ~ts wa's'-slignificariti~~ larger among mothers, ~ ~\:~'.~~.~.~~~!, (continued on, ~~~e 409) ;~~~~~~c~JW~"ϵMN~.~~ dled' after one year of age ~~~~ ~&s~ ~~~i~~~~ x ~c~~~ r~a~~ t~~ ~~~~~ri~ for SID S~ ~' t Fathers, occupation's are coded according, to, the U,,;S. tur~~4~u of Cet~~'us, ~~~5~~~~~~~ ~r~~d~~ ~~ ~~c~~~t~~~~~ ~~~N~L~a~hM~e~~Wa~m~t~~~B 1 950. °° Blue , coilar z~~~~~~r~" ~~nctu~e~'~cfa,ft$men,~.: tar<e<M~Ft~~~!'aM~;~M~~/;j. ~~~~~-~~ -c~~~~~er~s ~~~~~:~ ~~~r~~~~-~ a~~;~~b~~~r~ ~~:~~~~5~ ~'~r~~~. " . ,

PY - 1979/7

Y1 - 1979/7

UR - http://www.scopus.com/inward/record.url?scp=0018635240&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0018635240&partnerID=8YFLogxK

U2 - 10.1177/000992287901800704

DO - 10.1177/000992287901800704

M3 - Article

C2 - 455873

AN - SCOPUS:0018635240

SN - 0009-9228

VL - 18

SP - 404

EP - 405

JO - Clinical Pediatrics

JF - Clinical Pediatrics

IS - 7

ER -