Browsing by Subject "CIGARETTE-SMOKING"

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  • Loukola, Anu; Buchwald, Jadwiga; Gupta, Richa; Palviainen, Teemu; Hallfors, Jenni; Tikkanen, Emmi; Korhonen, Tellervo; Ollikainen, Miina; Sarin, Antti-Pekka; Ripatti, Samuli; Lehtimaki, Terho; Raitakari, Olli; Salomaa, Veikko; Rose, Richard J.; Tyndale, Rachel F.; Kaprio, Jaakko (2015)
    Individuals with fast nicotine metabolism typically smoke more and thus have a greater risk for smoking-induced diseases. Further, the efficacy of smoking cessation pharmacotherapy is dependent on the rate of nicotine metabolism. Our objective was to use nicotine metabolite ratio (NMR), an established biomarker of nicotine metabolism rate, in a genome-wide association study (GWAS) to identify novel genetic variants influencing nicotine metabolism. A heritability estimate of 0.81 (95% CI 0.70-0.88) was obtained for NMR using monozygotic and dizygotic twins of the FinnTwin cohort. We performed a GWAS in cotinine-verified current smokers of three Finnish cohorts (FinnTwin, Young Finns Study, FIN-RISK2007), followed by a meta-analysis of 1518 subjects, and annotated the genome-wide significant SNPs with methylation quantitative loci (meQTL) analyses. We detected association on 19q13 with 719 SNPs exceeding genome-wide significance within a 4.2 Mb region. The strongest evidence for association emerged for CYP2A6 (min p = 5.77E-86, in intron 4), the main metabolic enzyme for nicotine. Other interesting genes with genome-wide significant signals included CYP2B6, CYP2A7, EGLN2, and NUMBL. Conditional analyses revealed three independent signals on 19q13, all located within or in the immediate vicinity of CYP2A6. A genetic risk score constructed using the independent signals showed association with smoking quantity (p = 0.0019) in two independent Finnish samples. Our meQTL results showed that methylation values of 16 CpG sites within the region are affected by genotypes of the genome-wide significant SNPs, and according to causal inference test, for some of the SNPs the effect on NMR is mediated through methylation. To our knowledge, this is the first GWAS on NMR. Our results enclose three independent novel signals on 19q13.2. The detected CYP2A6 variants explain a strikingly large fraction of variance (up to 31%) in NMR in these study samples. Further, we provide evidence for plausible epigenetic mechanisms influencing NMR.
  • Kinnunen, Jaana M.; Lindfors, Pirjo; Rimpela, Arja; Salmela-Aro, Katariina; Rathmann, Katharina; Perelman, Julian; Federico, Bruno; Richter, Matthias; Kunst, Anton E.; Lorant, Vincent (2016)
    It is well established that poor academic performance is related to smoking, but the association between academic well-being and smoking is less known. We measured academic well-being by school burnout and schoolwork engagement and studied their associations with smoking among 14- to 17-year-old schoolchildren in Belgium, Germany, Finland, Italy, the Netherlands, and Portugal. A classroom survey (2013 SILNE survey, N = 11,015) was conducted using the Short School Burnout Inventory and the Schoolwork Engagement Inventory. Logistic regression, generalized linear mixed models, and ANOVA were used. Low schoolwork engagement and high school burnout increased the odds for daily smoking in all countries. Academic performance was correlated with school burnout and schoolwork engagement, and adjusting for it slightly decreased the odds for smoking. Adjusting for socioeconomic factors and school level had little effect. Although high school burnout and low schoolwork engagement correlate with low academic performance, they are mutually independent risk factors for smoking. (C) 2016 The Authors. Published by Elsevier Ltd on behalf of The Foundation for Professionals in Services for Adolescents.
  • Heikkala, Eveliina; Ala-Mursula, Leena; Taimela, Simo; Paananen, Markus; Vaaramo, Eeva; Auvinen, Juha; Karppinen, Jaro (2020)
    BackgroundThe relevance of health-related behaviors to exclusion from the labor market in early adulthood remains poorly studied in relation to the magnitude of the problem. We explored whether adolescents' accumulated unhealthy behaviors and psychosocial problems are associated with later labor market exclusion, and whether multisite musculoskeletal pain (MMSP) impacts these relations.MethodsWe gathered questionnaire data on unhealthy behaviors and psychosocial problems and MMSP among adolescents aged 15 to 16 belonging to the Northern Finland Birth Cohort 1986. The findings were combined with registry data on unemployment, employment and permanent work disability during a five-year follow-up between the ages of 25 and 29 (n=6692). In the statistical modeling we used education, family leave and socioeconomic status of childhood family as potential confounders, as well as latent class and logistic regression analyses.ResultsThe Externalizing behavior cluster associated with over one year of unemployment (RR 1.64, CI 1.25-2.14) and permanent work disability (OR 2.49, CI 1.07-5.78) in the follow-up among the men. The Sedentary cluster also associated with over one year (RR 1.41, CI 1.13-1.75) and under one year of unemployment (RR 1.25, CI 1.02-1.52) and no employment days (RR 1.93, CI 1.26-2.95) among the men. Obese male participants were at risk of over one year of unemployment (RR 1.50, CI 1.08-2.09) and no employment days (RR 1.93, CI 1.07-3.50). Among the women, the Multiple risk behavior cluster related significantly to over one year of unemployment (RR 1.77, CI 1.37-2.28). MMSP had no influence on the associations.ConclusionsUnhealthy behavior patterns and psychosocial problems in adolescence have long-term consequences for exclusion from the labor market in early adulthood, especially among men. Simultaneously supporting psychological well-being and healthy behaviors in adolescence may reduce labor market inclusion difficulties in the early phase of working life.
  • Heikkala, Eveliina; Remes, Jouko; Paananen, Markus; Taimela, Simo; Auvinen, Juha; Karppinen, Jaro (2014)
  • Ananth, Cande V.; Keyes, Katherine M.; Hamilton, Ava; Gissler, Mika; Wu, Chunsen; Liu, Shiliang; Luque-Fernandez, Miguel Angel; Skjaerven, Rolv; Williams, Michelle A.; Tikkanen, Minna; Cnattingius, Sven (2015)
    Background Although rare, placental abruption is implicated in disproportionately high rates of perinatal morbidity and mortality. Understanding geographic and temporal variations may provide in-sights into possible amenable factors of abruption. We examined abruption frequencies by maternal age, delivery year, and maternal birth cohorts over three decades across seven countries. Methods Women that delivered in the US (n = 863,879; 1979-10), Canada (4 provinces, n = 5,407,463; 1982-11), Sweden (n = 3,266,742; 1978-10), Denmark (n = 1,773,895; 197808), Norway (n = 1,780,271, 1978-09), Finland (n = 1,411,867; 1987-10), and Spain (n = 6,151,508; 1999-12) were analyzed. Abruption diagnosis was based on ICD coding. Rates were modeled using Poisson regression within the framework of an age-period-cohort analysis, and multi-level models to examine the contribution of smoking in four countries. Results Abruption rates varied across the seven countries (3-10 per 1000), Maternal age showed a consistent J-shaped pattern with increased rates at the extremes of the age distribution. In comparison to births in 2000, births after 2000 in European countries had lower abruption rates; in the US there was an increase in rate up to 2000 and a plateau thereafter. No birth cohort effects were evident. Changes in smoking prevalence partially explained the period effect in the US (P = 0.01) and Sweden (P <0.01). Conclusions There is a strong maternal age effect on abruption. While the abruption rate has plateaued since 2000 in the US, all other countries show declining rates. These findings suggest considerable variation in abruption frequencies across countries; differences in the distribution of risk factors, especially smoking, may help guide policy to reduce abruption rates.
  • Piirtola, Maarit; Kaprio, Jaakko; Silventoinen, Karri; Svedberg, Pia; Korhonen, Tellervo; Ropponen, Annina (2017)
    To investigate longitudinal associations of smoking and a change in smoking status with leisure-time physical inactivity. In addition, to control whether familial confounding (genetics and shared environment) influences the associations. Data were based on the population-based Finnish Adult Twin Cohort of 5254 twin individuals born in 1945-1957 (41% men) and who participated in all four surveys over a 35-year follow-up (1975-2011). Logistic and conditional logistic regression models with multiple covariates were used for analyses. Compared to never-smokers, long-term daily smokers (1975-1990) had the highest likelihood for both long-term inactivity and to change into inactive by 2011. Recurrent smoking was associated with long-term inactivity. Instead, in comparison to persistent daily smokers, quitting smoking decreased the likelihood of becoming physically inactive at leisure time. The associations remained in the analyses which accounted for multiple covariates and/or familial confounding. Daily smoking increases the likelihood of remaining or becoming physically inactive over the decades. Our results emphasize not only the importance of preventing smoking initiation, but also to support early smoking cessation in promotion of lifelong physical activity.
  • Broms, Ulla; Koskenvuo, Karoliina; Sillanmaki, Lauri H.; Mattila, Kari J.; Koskenvuo, Markku (2012)
  • Martiskainen, Mika; Oksala, Niku; Pohjasvaara, Tarja; Kaste, Markku; Oksala, Anni; Karhunen, Pekka J.; Erkinjuntti, Timo (2014)
  • de Oliveira Figueiredo, Rejane Augusta; Weiderpass, Elisabete; Tajara, Eloiza Helena; Strom, Peter; Carvalho, Andre Lopes; de Carvalho, Marcos Brasilino; Kanda, Jossi Ledo; Moyses, Raquel Ajub; Wunsch-Filho, Victor (2016)
    Introduction: Diabetes mellitus (DM (Diabetes Mellitus)) is directly associated with some cancers. However, studies on the association between diabetes mellitus and head and neck cancer (HNC (Head and Neck Cancer)) have rendered controversial results. The objective of this study was to evaluate the association between DM and HNC, as well as the impact of metformin use on the risk of HNC. Material and methods: This case-control study was conducted within the framework of the Brazilian Head and Neck Genome Project in 2011-2014. The study included 1021 HNC cases with histologically confirmed squamous cell carcinoma of the head and neck admitted to five large hospitals in Sao Paulo state. A total of 1063 controls were selected in the same hospitals. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression. Results: Diabetic participants had a decreased risk of HNC (OR = 0.68; 95% CI: 0.49-0.95) than nondiabetic participants, and this risk was further decreased among diabetic metformin users (OR = 0.54; 95% CI: 0.29-0.99). Diabetic metformin users that were current smokers (OR = 0.13; 95% CI: 0.04-0.44) or had an alcohol consumption of >40 g/day (OR = 0.31; 95% CI: 0.11-0.88) had lower risk of HNC than equivalent non-diabetic participants. Conclusion: The risk of HNC was decreased among diabetic participants; metformin use may at least partially explain this inverse association. (C) 2016 Elsevier Ltd. All rights reserved.
  • Finndiane Study Grp (2018)
    Aims/hypothesisThe aim of this study was to assess the potential dose-dependent effects of smoking on the risk of CHD, heart failure and stroke in individuals with type 1 diabetes.MethodsThe study included 4506 individuals with type 1 diabetes who were participating in the Finnish Diabetic Nephropathy (FinnDiane) study. Intensity of smoking was estimated by packs per day and cumulative smoking by pack-years. Cox regression analyses were used to estimate the risk of incident CHD, heart failure or stroke during follow-up.ResultsOne pack per day significantly increased the risk of incident CHD in current smokers compared with never smokers (HR 1.45 [95% CI 1.15, 1.84]), after adjustment for age, sex, HbA(1c), hypertension, duration of diabetes and BMI. The risk of CHD in former smokers was similar to the risk in never smokers. The risk of incident heart failure was 1.43 (95% CI 1.03, 1.97) in current smokers per one pack per day and 1.37 (95% CI 1.05, 1.77) in former smokers, while the risk of incident stroke was 1.70 (95% CI 1.26, 2.29) and 1.49 (95% CI 1.14, 1.93), respectively. After further adjustments for lipids, however, the difference in the risk of heart failure in current and former smokers was no longer significant. Cumulative smoking data were similar to smoking intensity data.Conclusions/interpretationThere is a dose-dependent association between smoking and cardiovascular disease in individuals with type 1 diabetes. In men in particular, the risk of incident stroke remains high even after smoking cessation and is increased in current and former smokers independently of other risk factors.
  • Korhonen, Tellervo; Sihvola, Elina; Latvala, Antti; Dick, Danielle M.; Pulkkinen, Lea; Nurnberger, John; Rose, Richard J.; Kaprio, Jaakko (2018)
    Background: Developmental relationships between tobacco use and suicide-related behaviors (SRB) remain unclear. Our objective was to investigate the longitudinal associations of tobacco use in adolescence and SRB in adulthood. Methods: Using a prospective design, we examined whether tobacco use in adolescence is associated with SRB (intentional self-injury, suicide ideation) in young adulthood in a population-based sample of 1330 twins (626 males, 704 females). The baseline and follow-up data were collected by professionally administered semi-structured poly-diagnostic interviews at ages 14 and 22, respectively. Results: After adjusting for multiple potential confounders, those who reported early-onset of regular tobacco use had a significantly increased risk for intentional self-injury, such as cutting or burning, at age 22 (adjusted odds ratio[AOR] 4.57, 95% CI 1.93-10.8) in comparison to those who had not at all initiated tobacco use. Also, daily cigarette smoking at baseline was associated with future intentional self-injury (AOR 4.45, 95% CI 2.04-9.70). Early-onset tobacco use was associated with suicidal ideation in females (AOR 3.69, 95% CI 1.56-8.72) but not in males. Considering any SRB, baseline daily smokers (AOR 2.13, 95% CI 1.12-4.07) and females with early onset of regular tobacco use (AOR 3.97, 95% CI 1.73-9.13) had an increased likelihood. Within-family analyses among twin pairs discordant for exposure and outcome controlling for familial confounds showed similar, albeit statistically non-significant, associations. Conclusion: Early-onset tobacco use in adolescence is longitudinally associated with SRB (intentional self-injury and/or suicide ideation) in young adulthood, particularly among females. Further investigation may reveal whether this association has implications for prevention of SRB in adolescence and young adulthood.
  • Mishra, Gita D.; Chung, Hsin-Fang; Cano, Antonio; Chedraui, Peter; Goulis, Dimitrios G.; Lopes, Patrice; Mueck, Alfred; Rees, Margaret; Senturk, Levent M.; Simoncini, Tommaso; Stevenson, John C.; Stute, Petra; Tuomikoski, Pauliina; Lambrinoudaki, Irene (2019)
    Introduction: While the associations of genetic, reproductive and environmental factors with the timing of natural menopause have been extensively investigated, few epidemiological studies have specifically examined their association with premature (<40 years) or early natural menopause (40-45 years). Aim: The aim of this position statement is to provide evidence on the predictors of premature and early natural menopause, as well as recommendations for the management of premature and early menopause and future research. Materials and methods: Literature review and consensus of expert opinion. Results and conclusions: Strong genetic predictors of premature and early menopause include a family history of premature or early menopause, being a child of a multiple pregnancy and some specific genetic variants. Women with early menarche and nulliparity or low parity are also at a higher risk of experiencing premature or early menopause. Cigarette smoking (with a strong dose-response effect) and being underweight have been consistently associated with premature and early menopause. Current guidelines for the management of premature and early menopause mainly focus on early initiation of hormone therapy (HT) and continued treatment until the woman reaches the average age at menopause (50-52 years). We suggest that clinicians and health professionals consider the age at menopause of the relevant region or ethnic group as part of the assessment for the timing of HT cessation. In addition, there should be early monitoring of women with a family history of early menopause, who are a child of a multiple pregnancy, or who have had early menarche (especially those who have had no children). As part of preventive health strategies, women should be encouraged to quit smoking (preferably before the age of 30 years) and maintain optimal weight in order to reduce their risk of premature or early menopause.
  • Steiner, Thorsten; Juvela, Seppo; Unterberg, Andreas; Jung, Carla; Forsting, Michael; Rinkel, Gabriel (2013)
  • The FinnDiane Study Group; Tikkanen-Dolenc, Heidi; Wadén, Johan; Forsblom, Carol; Harjutsalo, Valma; Thorn, Lena M.; Saraheimo, Markku; Elonen, Nina; Hietala, Kustaa; Summanen, Paula; Tikkanen, Heikki O.; Groop, Per-Henrik (2020)
    The aim of this study was to investigate whether leisure-time physical activity (LTPA) is associated with the development of severe diabetic retinopathy in individuals with type 1 diabetes.
  • Hancock, D. B.; Guo, Y.; Reginsson, G. W.; Gaddis, N. C.; Lutz, S. M.; Sherva, R.; Loukola, A.; Minica, C. C.; Markunas, C. A.; Han, Y.; Young, K. A.; Gudbjartsson, D. F.; Gu, F.; McNeil, D. W.; Qaiser, B.; Glasheen, C.; Olson, S.; Landi, M. T.; Madden, P. A. F.; Farrer, L. A.; Vink, J.; Saccone, N. L.; Neale, M. C.; Kranzler, H. R.; McKay, J.; Hung, R. J.; Amos, C. I.; Marazita, M. L.; Boomsma, D. I.; Baker, T. B.; Gelernter, J.; Kaprio, J.; Caporaso, N. E.; Thorgeirsson, T. E.; Hokanson, J. E.; Bierut, L. J.; Stefansson, K.; Johnson, E. O. (2018)
    Cigarette smoking is a leading cause of preventable mortality worldwide. Nicotine dependence, which reduces the likelihood of quitting smoking, is a heritable trait with firmly established associations with sequence variants in nicotine acetylcholine receptor genes and at other loci. To search for additional loci, we conducted a genome-wide association study (GWAS) meta-analysis of nicotine dependence, totaling 38,602 smokers (28,677 Europeans/European Americans and 9925 African Americans) across 15 studies. In this largest-ever GWAS meta-analysis for nicotine dependence and the largest-ever cross-ancestry GWAS meta-analysis for any smoking phenotype, we reconfirmed the well-known CHRNA5-CHRNA3-CHRNB4 genes and further yielded a novel association in the DNA methyltransferase gene DNMT3B. The intronic DNMT3B rs910083-C allele (frequency = 44-77%) was associated with increased risk of nicotine dependence at P = 3.7 x 10(-8) (odds ratio (OR) = 1.06 and 95% confidence interval (CI) = 1.04-1.07 for severe vs mild dependence). The association was independently confirmed in the UK Biobank (N = 48,931) using heavy vs never smoking as a proxy phenotype (P = 3.6 x 10(-4), OR = 1.05, and 95% CI = 1.02-1.08). Rs910083-C is also associated with increased risk of squamous cell lung carcinoma in the International Lung Cancer Consortium (N = 60,586, meta-analysis P = 0.0095, OR = 1.05, and 95% CI = 1.01-1.09). Moreover, rs910083-C was implicated as a cis-methylation quantitative trait locus (QTL) variant associated with higher DNMT3B methylation in fetal brain (N = 166, P = 2.3 x 10(-26)) and a cis-expression QTL variant associated with higher DNMT3B expression in adult cerebellum from the Genotype-Tissue Expression project (N = 103, P = 3.0 x 10(-6)) and the independent Brain eQTL Almanac (N = 134, P = 0.028). This novel DNMT3B cis-acting QTL variant highlights the importance of genetically influenced regulation in brain on the risks of nicotine dependence, heavy smoking and consequent lung cancer.
  • Morris, Richard W.; Taylor, Amy E.; Fluharty, Meg E.; Bjorngaard, Johan H.; Asvold, Bjorn Olav; Gabrielsen, Maiken Elvestad; Campbell, Archie; Marioni, Riccardo; Kumari, Meena; Korhonen, Tellervo; Mannisto, Satu; Marques-Vidal, Pedro; Kaakinen, Marika; Cavadino, Alana; Postmus, Iris; Husemoen, Lise Lotte N.; Skaaby, Tea; Ahluwalia, Tarun Veer Singh; Treur, Jorien L.; Willemsen, Gonneke; Dale, Caroline; Wannamethee, S. Goya; Lahti, Jari; Palotie, Aarno; Räikkönen, Katri; McConnachie, Alex; Padmanabhan, Sandosh; Wong, Andrew; Dalgard, Christine; Paternoster, Lavinia; Ben-Shlomo, Yoav; Tyrrell, Jessica; Horwood, John; Fergusson, David M.; Kennedy, Martin A.; Nohr, Ellen A.; Christiansen, Lene; Kyvik, Kirsten Ohm; Kuh, Diana; Watt, Graham; Eriksson, Johan G.; Whincup, Peter H.; Vink, Jacqueline M.; Boomsma, Dorret I.; Smith, George Davey; Lawlor, Debbie; Linneberg, Allan; Ford, Ian; Jukema, J. Wouter; Power, Chris; Hypponen, Elina; Jarvelin, Marjo-Riitta; Preisig, Martin; Borodulin, Katja; Kaprio, Jaakko; Kivimaki, Mika; Smith, Blair H.; Hayward, Caroline; Romundstad, Pal R.; Sorensen, Thorkild I. A.; Munafo, Marcus R.; Sattar, Naveed (2015)
    Objectives: To investigate, using a Mendelian randomisation approach, whether heavier smoking is associated with a range of regional adiposity phenotypes, in particular those related to abdominal adiposity. Design: Mendelian randomisation meta-analyses using a genetic variant (rs16969968/rs1051730 in the CHRNA5-CHRNA3-CHRNB4 gene region) as a proxy for smoking heaviness, of the associations of smoking heaviness with a range of adiposity phenotypes. Participants: 148 731 current, former and neversmokers of European ancestry aged >= 16 years from 29 studies in the consortium for Causal Analysis Research in Tobacco and Alcohol (CARTA). Primary outcome measures: Waist and hip circumferences, and waist-hip ratio. Results: The data included up to 66 809 never-smokers, 43 009 former smokers and 38 913 current daily cigarette smokers. Among current smokers, for each extra minor allele, the geometric mean was lower for waist circumference by -0.40% (95% Cl -0.57% to - 0.22%), with effects on hip circumference, waist-hip ratio and body mass index (BMI) being -0.31% (95% Cl - 0.42% to -0.19), -0.08% (-0.19% to 0.03%) and - 0.74% (-0.96% to -0.51%), respectively. In contrast, among never-smokers, these effects were higher by 0.23% (0.09% to 0.36%), 0.17% (0.08% to 0.26%), 0.07% (-0.01% to 0.15%) and 0.35% (0.18% to 0.52%), respectively. When adjusting the three central adiposity measures for BMI, the effects among current smokers changed direction and were higher by 0.14% (0.05% to 0.22%) for waist circumference, 0.02% (-0.05% to 0.08%) for hip circumference and 0.10% (0.02% to 0.19%) for waist-hip ratio, for each extra minor allele. Conclusions: For a given BMI, a gene variant associated with increased cigarette consumption was associated with increased waist circumference. Smoking in an effort to control weight may lead to accumulation of central adiposity.
  • Böckerman, Petri; Hyytinen, Ari; Kaprio, Jaakko; Maczulskij, Terhi (2018)
    This paper examines the links between risky health behaviors and labor market success. We provide new evidence on the joint relationships between the most prominent forms of risky health behavior - alcohol consumption, smoking and physical inactivity - and long-term labor market outcomes. We use twin data for Finnish men and women linked to register-based individual information on earnings and labor market attachment. The twin data allow us to account for shared family and environmental factors and to measure risky health behaviors in 1975 and 1981. The long-term labor market outcomes were measured in adulthood as an average over the period 1990-2009. The sample sizes are 2156 and 2498 twins, for men and women, respectively. We find that being both a smoker and a heavy drinker in early adulthood is negatively related to long-term earnings and employment later in life, especially for men. We conclude that how and why risky health behaviors cluster and how that affects individual level outcomes call for more attention.
  • Masalin, Senja; Kautiainen, Hannu; Gissler, Mika; Pennanen, Pirjo; Eriksson, Johan G.; Laine, Merja K. (2020)
    Introduction Smoking has been shown to affect glucose homeostasis and increase the risk for type 2 diabetes mellitus. Further, gestational diabetes mellitus (GDM) and smoking are known to influence offspring birthweight. The effect of smoking on glucose homeostasis in pregnancy is less studied and the findings are inconsistent. The aim of this study was to evaluate the effect of smoking on risk for GDM and to evaluate the impact of smoking and GDM on offspring birthweight. Material and methods This is an observational cohort study encompassing 4111 Finnish primiparous women from the city of Vantaa, Finland, who delivered a singleton child between 2009 and 2015. Data were obtained from Finnish national registers. Study participants had complete oral glucose tolerance test results and were divided into three groups according to smoking status: non-smokers (I), smokers who quit during first trimester (II), and smokers who continued after first trimester (III). Results Prevalence of GDM was 19.8%, 24.3%, and 26.6% in non-smokers, those who quit, and those who continued after the first trimester, respectively (P = .004 for differences between groups). The odds ratio for GDM in smokers who continued after the first trimester compared with non-smokers was 1.65 (95% CI 1.09-2.57) after adjustments for age, prepregnancy body mass index, education, and cohabitation. In women without GDM, offspring birthweight was lowest in those who continued smoking after the first trimester (P = .010 for differences between groups). In women with GDM, smoking status did not influence offspring birthweight. Conclusions Smoking during pregnancy is associated with an increased risk for GDM. Offspring birthweight is lowest in women who continue smoking after the first trimester. If pregnancy is complicated by GDM, offspring birthweight is not influenced by smoking.
  • Skaaby, Tea; Taylor, Amy E.; Jacobsen, Rikke K.; Paternoster, Lavinia; Thuesen, Betina H.; Ahluwalia, Tarunveer S.; Larsen, Sofus C.; Zhou, Ang; Wong, Andrew; Gabrielsen, Maiken E.; Bjorngaard, Johan H.; Flexeder, Claudia; Mannisto, Satu; Hardy, Rebecca; Kuh, Diana; Barry, Sarah J.; Mollehave, Line Tang; Cerqueira, Charlotte; Friedrich, Nele; Bonten, Tobias N.; Noordam, Raymond; Mook-Kanamori, Dennis O.; Taube, Christian; Jessen, Leon E.; McConnachie, Alex; Sattar, Naveed; Upton, Mark N.; McSharry, Charles; Bonnelykke, Klaus; Bisgaard, Hans; Schulz, Holger; Strauch, Konstantin; Meitinger, Thomas; Peters, Annette; Grallert, Harald; Nohr, Ellen A.; Kivimaki, Mika; Kumari, Meena; Voelker, Uwe; Nauck, Matthias; Voeizke, Henry; Power, Chris; Hypponen, Elina; Hansen, Torben; Jorgensen, Torben; Pedersen, Oluf; Salomaa, Veikko; Grarup, Niels; Langhammer, Arnulf; Romundstad, Pal R.; Skorpen, Frank; Kaprio, Jaakko; Munafo, Marcus R.; Linneberg, Allan (2017)
    Observational studies on smoking and risk of hay fever and asthma have shown inconsistent results. However, observational studies may be biased by confounding and reverse causation. Mendelian randomization uses genetic variants as markers of exposures to examine causal effects. We examined the causal effect of smoking on hay fever and asthma by using the smoking-associated single nucleotide polymorphism (SNP) rs16969968/rs1051730. We included 231,020 participants from 22 population-based studies. Observational analyses showed that current vs never smokers had lower risk of hay fever (odds ratio (OR) = 0.68, 95% confidence interval (CI): 0.61, 0.76; P <0.001) and allergic sensitization (OR = 0.74, 95% CI: 0.64, 0.86; P <0.001), but similar asthma risk (OR = 1.00, 95% CI: 0.91, 1.09; P = 0.967). Mendelian randomization analyses in current smokers showed a slightly lower risk of hay fever (OR = 0.958, 95% CI: 0.920, 0.998; P = 0.041), a lower risk of allergic sensitization (OR = 0.92, 95% CI: 0.84, 1.02; P = 0.117), but higher risk of asthma (OR = 1.06, 95% CI: 1.01, 1.11; P = 0.020) per smoking-increasing allele. Our results suggest that smoking may be causally related to a higher risk of asthma and a slightly lower risk of hay fever. However, the adverse events associated with smoking limit its clinical significance.