Maternal Cotinine Levels and Red Blood Cell Folate Concentrations in the Periconceptual Period

Authors: Korede K. Yusuf, MBBS, PhD, Roneé Wilson, PhD, Alfred Mbah, PhD, William Sappenfield, MD, Lindsey M. King, PhD, MPH, Hamisu M. Salihu, MD, PhD


Objectives: Studies have examined the association between tobacco use and folate levels in pregnancy, yet few have assessed this relation using objective and accurate measures of both smoking and folate. In this study, we evaluated the association between maternal cotinine levels and periconceptional red blood cell (RBC) folic acid reserves in a cohort of low-income pregnant mothers.

Methods: Smoking information, based on salivary cotinine, a highly sensitive and specific tobacco smoke exposure biomarker, was used. Furthermore, folate was assessed using RBC folate, an indicator of long-term folate storage. Participants were early to mid-trimester pregnant women who received antenatal care between 2011 and 2015 at the Genesis Clinic of Tampa (Florida). A total of 496 women were enrolled in the study. Associations between smoking status/maternal salivary cotinine concentrations, sociodemographic factors, and folate concentrations were investigated using Tobit regression analyses.

Results: The mean folate level of the participants was 718.3 ± 183.2 ng/mL, and only 2 (0.4%) participants were deficient in folate. We observed no significant difference in folate levels by smoking status. In contrast, salivary cotinine levels were significantly associated with decreased RBC folate concentrations (β −11.43, standard error 5.45, P = 0.032). Prepregnancy maternal body mass index, gestational age, stress, and depression also were associated with folate levels.

Conclusions: Low RBC folate is associated with perinatal factors, including high maternal cotinine levels, body mass index, stress, and depression. The effect of low folate levels among smokers cannot be overemphasized, considering that tobacco products not only reduce folate levels but also decrease the bioutilization of folate.

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1. Antony AC. In utero physiology: role of folic acid in nutrient delivery and fetal development. Am J Clin Nutr 2007;85:598S-603S.
2. Greenberg JA, Bell SJ, Guan Y, et al. Folic acid supplementation and pregnancy: more than just neural tube defect prevention. Rev Obstet Gynecol 2011;4:52-59.
3. De-Regil LM, Fernandez-Gaxiola AC, Dowswell T, et al. Effects and safety of periconceptional folate supplementation for preventing birth defects. Cochrane Database Syst Rev 2010;10:CD007950.
4. Pfeiffer CM, Sternberg MR, Fazili Z, et al. Folate status and concentrations of serum folate forms in the US population: National Health and Nutrition Examination Survey 2011-2. Br J Nutr 2015;113:1965-1977.
5. Ozerol E, Ozerol I, Gokdeniz R, et al. Effect of smoking on serum concentrations of total homocysteine, folate, vitamin B12, and nitric oxide in pregnancy: a preliminary study. Fetal Diagn Ther 2004;19:145-148.
6. Prasodjo A, Pfeiffer CM, Fazili Z, et al. Serum cotinine and whole blood folate concentrations in pregnancy. Ann Epidemiol 2014;24:498-503.e1.
7. Jauniaux E, Johns J, Gulbis B, et al. Transfer of folic acid inside the first-trimester gestational sac and the effect of maternal smoking. Am J Obstet Gynecol 2007;197:58.e1-58.e6.
8. Mannino DM, Mulinare J, Ford ES, et al. Tobacco smoke exposure and decreased serum and red blood cell folate levels: data from the third National Health and Nutrition Examination Survey. Nicotine Tob Res 2003;5:357-362.
9. Stark KD, Pawlosky RJ, Beblo S, et al. Status of plasma folate after folic acid fortification of the food supply in pregnant African American women and the influences of diet, smoking, and alcohol consumption. Am J Clin Nutr 2005;81:669-677.
10. van Wersch JW, Janssens Y, Zandvoort JA. Folic acid, vitamin B(12), and homocysteine in smoking and non-smoking pregnant women. Eur J Obstet Gynecol Reprod Biol 2002;103:18-21.
11. Pagan K, Hou J, Goldenberg RL, et al. Effect of smoking on serum concentrations of total homocysteine and B vitamins in mid-pregnancy. Clin Chim Acta 2001;306:103-109.
12. Schmidt RJ, Tancredi DJ, Ozonoff S, et al. Maternal periconceptional folic acid intake and risk of autism spectrum disorders and developmental delay in the CHARGE (childhood autism risks from genetics and environment) case-control study. Am J Clin Nutr 2012;96:80-89.
13. Fekete K, Berti C, Trovato M, et al. Effect of folate intake on health outcomes in pregnancy: a systematic review and meta-analysis on birth weight, placental weight and length of gestation. Nutr J 2012;11:75.
14. Anderka M, Romitti PA, Sun L, et al. Patterns of tobacco exposure before and during pregnancy. Acta Obstet Gynecol Scand 2010;89:505-514.
15. Tong VT, Dietz PM, Morrow B, et al. Trends in smoking before, during, and after pregnancy-pregnancy risk assessment monitoring system, United States, 40 sites, 2000-2010. MMWR Surveill Summ 2013;62:1-19.
16. Pirkle JL, Flegal KM, Bernert JT, et al. Exposure of the US population to environmental tobacco smoke: the third national health and nutrition examination survey, 1988 to 1991. JAMA 1996;275:1233-1240.
17. US Department of Health and Human Services. The Health Consequences of Smoking: A Report of the Surgeon General. Atlanta, GA:Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health;2004.
18. McDonald SD, Perkins SL, Jodouin CA, et al. Folate levels in pregnant women who smoke: an important gene/environment interaction. Am J Obstet Gynecol 2002;187:620-625.
19. Dastur DK, Quadros EV, Wadia NH, et al. Effect of vegetarianism and smoking on vitamin B12, thiocyanate, and folate levels in the blood of normal subjects. Br Med J 1972;3:260-263.
20. DeLorenze GN, Kharrazi M, Kaufman FL, et al. Exposure to environmental tobacco smoke in pregnant women: the association between self-report and serum cotinine. Environ Res 2002;90:21-32.
21. World Health Organization. Serum and Red Blood Cell Folate Concentrations for Assessing Folate Status in Populations. WHO/NMH/NHD/EPG/15.01. Geneva:World Health Organization; 2015.
22. Froscher W, Maier V, Laage M, et al. Folate deficiency, anticonvulsant drugs, and psychiatric morbidity. Clin Neuropharmacol 1995;18:165-182.
23. Pietrzik K, Lamers Y, Bramswig S, et al. Calculation of red blood cell folate steady state conditions and elimination kinetics after daily supplementation with various folate forms and doses in women of childbearing age. Am J Clin Nutr 2007;86:1414-1419.
24. Benet LZ, Zia-Amirhosseini P. Basic principles of pharmacokinetics. Toxicol Pathol 1995;23:115-123.
25. Gregory JF, 3rd da Silva VR, Lamers Y. Kinetics of folate and one-carbon metabolism. In: Folate in Health and Disease , 2nd ed. Bailey LB, , ed. Boca Raton FL:CRC Press;2010: 491-516.
26. Quest Diagnostics. Folate, RBC. Accessed July 27, 2019.
27. Louis-Jacques AF, Salihu HM, King LM, et al. A positive association between umbilical cord RBC folate and fetal TL at birth supports a potential for fetal reprogramming. Nutr Res 2016;36:703-709.
28. Honarmand M, Nakhaee A, Moradi M. Comparison of salivary cotinine concentrations in male smokers and smokeless tobacco users. Asian Pac J Cancer Prev 2018;19:1363-1366.
29. Russell T, Crawford M, Woodby L. Measurements for active cigarette smoke exposure in prevalence and cessation studies: why simply asking pregnant women isn’t enough. Nicotine Tob Res 2004;6(suppl 2):S141-S151.
30. Branum AM, Bailey R, Singer BJ. Dietary supplement use and folate status during pregnancy in the United States. J Nutr 2013;143:486-492.
31. Centers for Disease Control and Prevention. Folate status in women of childbearing age, by race/ethnicity-United States, 1999-2000. MMWR Morb Mortal Wkly Rep 2002;51:808-810.
32. Crittenden KS, Manfredi C, Cho YI, et al. Smoking cessation processes in low-SES women: the impact of time-varying pregnancy status, health care messages, stress, and health concerns. Addict Behav 2007;32:1347-1366.
33. Orr ST, Blazer DG, Orr CA. Maternal prenatal depressive symptoms, nicotine addiction, and smoking-related knowledge, attitudes, beliefs, and behaviors. Matern Child Health J 2012;16:973-978.
34. Murray D, Cox JL. Screening for Depression during Pregnancy with the Edinburgh Depression Scale (EDDS) , Vol 8. London:Routledge;1990;pp. 99-107.
35. Cox JL, Holden JM, Sagovsky R. Detection of postnatal depression. Development of the 10-item Edinburgh Postnatal Depression Scale. Br J Psychiatry 1987;150:782-786.
36. Cohen S, Kamarck T, Mermelstein R. A global measure of perceived stress. J Health Soc Behav 1983;24:385-396.
37. Conover WJ. Practical Nonparametric Statistics , 3rd ed. New York:John Wiley & Sons; 1999.
38. Tobin J. Estimation of relationships for limited dependent variables. Econometrica 1958;26:24-36.
39. UCLA Statistical Consulting Group. Tobit analysis-SAS data analysis examples. Accessed July 1, 2018.
40. Subar AF, Harlan LC, Mattson ME. Food and nutrient intake differences between smokers and non-smokers in the US. Am J Public Health 1990;80:1323-1329.
41. Mansoor MA, Kristensen O, Hervig T, et al. Low concentrations of folate in serum and erythrocytes of smokers: methionine loading decreases folate concentrations in serum of smokers and nonsmokers. Clin Chem 1997;43:2192-2194.
42. Ortega RM, Lopez-Sobaler AM, Gonzalez-Gross MM, et al. Influence of smoking on folate intake and blood folate concentrations in a group of elderly spanish men. J Am Coll Nutr 1994;13:68-72.
43. Scholl TO, Johnson WG. Folic acid: influence on the outcome of pregnancy. Am J Clin Nutr 2000;71(5 suppl):1295S-1303S.
44. Royston P, Altman DG, Sauerbrei W. Dichotomizing continuous predictors in multiple regression: a bad idea. Stat Med 2006;25:127-141.
45. Naggara O, Raymond J, Guilbert F, et al. Analysis by categorizing or dichotomizing continuous variables is inadvisable: an example from the natural history of unruptured aneurysms. AJNR Am J Neuroradiol 2011;32:437-440.
46. Shen M, Chaudhry SH, MacFarlane AJ, et al. Serum and red-blood-cell folate demonstrate differential associations with BMI in pregnant women. Public Health Nutr 2016;19:2572-2579.
47. Bird JK, Ronnenberg AG, Choi SW, et al. Obesity is associated with increased red blood cell folate despite lower dietary intakes and serum concentrations. J Nutr 2015;145:79-86.
48. Tinker SC, Hamner HC, Qi YP, et al. U.S. women of childbearing age who are at possible increased risk of a neural tube defect-affected pregnancy due to suboptimal red blood cell folate concentrations, national health and nutrition examination survey 2007 to 2012. Birth Defects Res A Clin Mol Teratol 2015;103:517-526.
49. da Silva RP, Kelly KB, Al Rajabi A, et al. Novel insights on interactions between folate and lipid metabolism. Biofactors 2014;40:277-283.
50. Gori AM, Sofi F, Corsi AM, et al. Predictors of vitamin B6 and folate concentrations in older persons: the InCHIANTI study. Clin Chem 2006;52:1318-1324.
51. Berry RJ, Li Z, Erickson JD, et al. Prevention of neural-tube defects with folic acid in China. China-U.S. collaborative project for neural tube defect prevention. N Engl J Med 1999;341:1485-1490.
52. World Health Organization. Optimal serum and red blood cell folate concentrations in women of reproductive age for prevention of neural tube defects. Guideline. Published 2015. Accessed July 27, 2019.
53. Wolff T, Witkop CT, Miller T, et al. Folic acid supplementation for the prevention of neural tube defects: an update of the evidence for the U.S. preventive services task force. Ann Intern Med 2009;150:632-639.
54. Chamberlain C, O’Mara-Eves A, Oliver S, et al. Psychosocial interventions for supporting women to stop smoking in pregnancy. Cochrane Database Syst Rev 2013;10:CD001055.
55. Rasmussen M, Heitmann BL, Tonnesen H. Effectiveness of the gold standard programmes (GSP) for smoking cessation in pregnant and non-pregnant women. Int J Environ Res Public Health 2013;10:3653-3666.
56. Ondersma SJ, Svikis DS, Lam PK, et al. A randomized trial of computer-delivered brief intervention and low-intensity contingency management for smoking during pregnancy. Nicotine Tob Res 2012;14:351-360.