Parallel Incidences of Sudden Infant Death Syndrome and Infantile Hypertrophic Pyloric Stenosis: A Common Cause?

Abstract

ABSTRACT. Objective. To determine whether there was a correlation between the incidence of infantile hypertrophic pyloric stenosis (IHPS) and the incidence of sudden infant death syndrome (SIDS) during the period 1970 to 1997 and to discuss different causative factors that could be influencing the changing trend in incidence.Methods. We compared the incidence of IHPS in the Stockholm Health Care Region with the incidence of SIDS in Sweden each year between 1970 and 1997. First, the relation was assessed by calculation of a correlation coefficient; second, the relative linear decrease was estimated for the time period 1990 to 1997.Results. The incidence of IHPS increased steadily during the 1970s, from 0.5 per 1000 live births in 1970 to 2.7 in 1979. During the 1980s, the average incidence was 2.8. During the 1990s, there was a significant decrease in the number of IHPS cases in Stockholm. The incidence rate of IHPS parallels the incidence of SIDS during the study period (r ‫؍‬ 0.58). The incidence of SIDS dropped after the risk-reduction campaign in the beginning of the 1990s, which recommended that infants sleep on their back. We could not identify any other changes of behavioral risk factors in early exposures that could explain the temporal trends.Conclusions. The statistical findings suggest that IHPS and SIDS have causative factors in common. We suggest that prone sleeping is one of those factors. Pediatrics 2001;108(4). URL: http://www.pediatrics.org/ cgi/content/full/108/4/e70; infantile hypertrophic pyloric stenosis, sudden infant death syndrome, epidemiology.ABBREVIATIONS. IHPS, infantile hypertrophic pyloric stenosis; SIDS, sudden infant death syndrome; CI, confidence interval. I nfantile hypertrophic pyloric stenosis (IHPS) is a hypertrophy of the pyloric circular muscle sphincter of unknown cause. IHPS is categorized as a congenital malformation, but most often the muscular hypertrophy is absent at birth. 1 The hypertrophy develops gradually until it obstructs the gastric outlet, resulting in postprandial nonbilious projectile vomiting. The onset of clinical symptoms usually occurs at 2 to 4 weeks of age. IHPS is effectively treated with surgical pyloromyotomy, which permanently relieves the obstruction.The prevalence of a family history of IHPS is 13% to 14%, and the sex ratio (male:female) is 4 to 4.5:1. [1][2][3][4][5][6][7] The increased risk among relatives and the sex distribution strongly suggest that genetic factors are important. The inheritance pattern cannot be explained by Mendelian genetics; instead, IHPS has served as a prototype for the multifactorial threshold model of inheritance. 8 IHPS has been reported to be associated with a number of different exposures. Apart from male sex and white ethnicity, the results from different studies have been contradictory. 6 Feeding habits, maternal stress, high birth weight, and primogeniture are some exposures that have been implicated. 9 -13 A recent report suggested oral erythromycin intake as a possible risk factor for IHPS. 14 Erythromycin in...

Familial Aggregation and Heritability of Pyloric Stenosis

“…8 Among white individuals, pyloric stenosis is relatively common, 2,3,5,[8][9][10] with an incidence of 1.5 to 3 per 1000 live births. 9,10 Other than male sex, 2,3,9-11 the most consistently reported risk factors for pyloric stenosis are a family history of pyloric stenosis [2][3][4]8,10,[12][13][14][15][16][17][18][19][20][21] and being a firstborn child. [2][3][4]11,22 The epidemiological features of skewed sex distribution and clustering of cases within families suggest a genetic component to the etiology.…”

Correlation of Maternal Age and Migration on IHPS Epidemiology in Germany 2000-2008

“…The previous hypothesis that IHPS might be correlated with SIDS was based on data presented by Persson et al They speculated that the parallel decline in SIDS and IHPS incidence could be attributed to the campaign against prone sleeping positions [6].…”

“…Recently, numerous reports have shown a decline in IHPS incidence in various regions of the world, with dramatic decreases in Denmark and Sweden [6,11,16,17] Epidemiological cues have been used to suggest partial etiological explanations.…”

A novel missense mutation in the transcription factor FOXF1 cosegregating with infantile hypertrophic pyloric stenosis in the extended pedigree linked to IHPS5 on chromosome 16q24

“…A prone sleeping position has been proposed and investigated as a potential cause of IHPS. This theory stemmed from the observation of parallel decreasing incidences of IHPS and sudden infant death syndrome (SIDS) 3 . However, the most recent longitudinal study does not support this theory 4 .…”