| Autor: |
Kagan, K. O., Frisova, V., Nicolaides, K. H., Spencer, K. |
| Zdroj: |
Prenatal Diagnosis; Sep2007, Vol. 27 Issue 9, p849-853, 5p |
| Abstrakt: |
Objective To examine whether in smokers there is a significant dose dependency between the number of cigarettes per day and levels of free ß-hCG and pregnancy-associated plasma protein A (PAPP-A) at 11-13+6 weeks of gestation. Methods This was a retrospective analysis of the maternal serum free ß-hCG and PAPP-A levels in relation to the maternal smoking status in 109 263 chromosomally normal singleton pregnancies that had undergone first-trimester screening for Down syndrome by a combination of fetal nuchal translucency thickness and maternal serum biochemistry. Results There were 95 287 nonsmokers and 13 976 cigarette smokers. The overall median PAPP-A MoM among cigarette smokers was 0.827, which was 19.6% lower than the value of 1.029 in nonsmokers ( p < 0.0001 for log10 MoM). The respective values for β-hCG MoM were 1.003 for smokers and 1.035 for nonsmokers ( p < 0.0001 for log10 MoM) which corresponds to a reduction of 3.1%. There was a significant inverse relationship between the number of cigarettes per day and the level of PAPP-A MoM ( r = 0.989, p < 0.0001) but not the level of free β-hCG MoM ( r = 0.733; p = 0.098). Using a statistical modeling approach we found that the screen-positive rate when correcting the PAPP-A MoM by an all or nil smoking factor was reduced by only 0.1% (3.75 vs 3.85%) when compared to correcting with a factor related to the smoking dose per day. Conclusion In first-trimester screening for Down syndrome by maternal serum PAPP-A and free β-hCG the impact of correcting for the dose dependant rather than the all or nil effect of smoking is marginal. However, a dose dependent correction improves the accuracy of the individual patient-specific risk. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Plný text