Neurodevelopment of infants with single-suture craniosynostosis: presurgery comparisons with case-matched controls.

BACKGROUND: The hypothesized association between single-suture craniosynostosis and neurodevelopment remains unclear, given the methodologic limitations of previous studies, most notably the absence of control groups. METHODS: Standardized measures were used to assess the neurodevelopment of 125 matched case-control pairs shortly after cases were first diagnosed with isolated fusions of the sagittal, metopic, lambdoid, or right or left coronal sutures. Participants varied in age from 2 to 24 months. RESULTS: Cases had significantly lower mean standardized scores than controls on measures of cognitive ability and motor functioning (p < 0.02). These differences were unaffected by the location of synostosis, age of diagnosis, infant sex, and maternal IQ. Measures of early language functions revealed no group differences. CONCLUSIONS: Before cranioplasty, single-suture craniosynostosis is associated with modest but reliable neurodevelopmental delays that cannot be attributed to maternal intelligence and family sociodemographic variables. Follow-up of this sample will determine the predictive significance of these delays. In the meantime, routine neurodevelopmental screening of infants with isolated craniosynostosis is recommended.

A twin study of genetic and dietary influences on nephrolithiasis: a report from the Vietnam Era Twin (VET) Registry.

BACKGROUND: Nephrolithiasis is a complex phenotype that is influenced by both genetic and environmental factors. We conducted a large twin study to examine genetic and nongenetic factors associated with stones. METHODS: The VET Registry includes approximately 7500 male-male twin pairs born between 1939 to 1955 with both twins having served in the military from 1965 to 1975. In 1990, a mail and telephone health survey was sent to 11,959 VET Registry members; 8870 (74.2%) provided responses. The survey included a question asking if the individual had ever been told of having a kidney stone by a physician. Detailed dietary habits were elicited. In a classic twin study analysis, we compared concordance rates in monozygotic (MZ) and dizygotic (DZ) twins. We also conducted a cotwin control study of dietary risk factors in twins discordant for stones. RESULTS: Among dizygotic twins, there were 17 concordant pairs and 162 discordant pairs for kidney stones. Among monozygotic twins, there were 39 concordant pairs and 163 discordant pairs. The proband concordance rate in MZ twins (32.4%) was significantly greater than the rate in DZ twins (17.3%) (chi(2)= 12.8; P < 0.001), consistent with a genetic influence. The heritability of the risk for stones was 56%. In the multivariate analysis of twin pairs discordant for kidney stones, we found a protective dose-response pattern of coffee drinking (P= 0.03); those who drank 5 or more cups of coffee were half as likely to develop kidney stones as those who did not drink coffee (OR = 0.4, 95% CI 0.2, 0.9). Those who drank at least 1 cup of milk per day were half as likely to report kidney stones (OR = 0.5, 95% CI 0.3, 0.8). There were also marginally significant protective effects of increasing numbers of cups of tea per day and frequent consumption of fruits and vegetables. Other factors such as the use of calcium supplements, alcohol drinking, consumption of solid dairy products, and the amount of animal protein consumed were not significantly related to kidney stones in the multivariate model. CONCLUSION: These results confirm that nephrolithiasis is at least in part a heritable disease. Coffee, and perhaps tea, fruits, and vegetables were found to be protective for stone disease. This is the first twin study of kidney stones, and represents a new approach to elucidating the relative roles of genetic and environmental factors associated with stone formation.