Investigating causality in associations between smoking initiation and schizophrenia using Mendelian randomization.
- Authors
- Gage, Suzanne H; Jones, Hannah J; Taylor, Amy E; Burgess, Stephen; Zammit, Stanley; MunafΓ², Marcus R
- Year
- 2017
- Journal
- Scientific reports
- PMID
- 28102331
- DOI
- 10.1038/srep40653
- PMCID
- PMC5244403
Smoking is strongly associated with schizophrenia. Although it has been widely assumed that this reflects self-medication, recent studies suggest that smoking may be a risk factor for schizophrenia. We performed two-sample bi-directional Mendelian randomization using summary level genomewide association data from the Tobacco And Genetics Consortium and Psychiatric Genomics Consortium. Variants associated with smoking initiation and schizophrenia were combined using an inverse-variance weighted fixed-effects approach. We found evidence consistent with a causal effect of smoking initiation on schizophrenia risk (OR 1.73, 95% CI 1.30-2.25, pβ<β0.001). However, after relaxing the p-value threshold to include variants from more than one gene and minimize the potential impact of pleiotropy, the association was attenuated (OR 1.03, 95% CI 0.97-1.09, pβ=β0.32). There was little evidence in support of a causal effect of schizophrenia on smoking initiation (OR 1.01, 95% CI 0.98-1.04, pβ=β0.32). MR Egger regression sensitivity analysis indicated no evidence for pleiotropy in the effect of schizophrenia on smoking initiation (intercept OR 1.01, 95% CI 0.99-1.02, pβ=β0.49). Our findings provide little evidence of a causal association between smoking initiation and schizophrenia, in either direction. However, we cannot rule out a causal effect of smoking on schizophrenia related to heavier, lifetime exposure, rather than initiation.
No entities extracted from this document yet.
No uploaded files.
| Citation | PMID | DOI | Status |
|---|---|---|---|
| Addo-YoboE. . Oral amoxicillin versus injectable penicillin for severe pneumonia in children aged 3 to 59 months: a randomised multicentre equivalency study. Lancet 364, 1141β1148, doi: 10.1016/S0140-6736(04)17100-6 (2004).15451221 | β | β | β |
| AutryA. E. & MonteggiaL. M. Brain-derived neurotrophic factor and neuropsychiatric disorders. Pharmacological reviews 64, 238β258, doi: 10.1124/pr.111.005108 (2012).22407616PMC3310485 | β | β | β |
| BowdenJ., Davey SmithG. & BurgessS. Mendelian randomization with invalid instruments: effect estimation and bias detection through Egger regression. International journal of epidemiology 44, 512β525, doi: 10.1093/ije/dyv080 (2015).26050253PMC4469799 | β | β | β |
| Bulik-SullivanB. . An atlas of genetic correlations across human diseases and traits. Nature genetics 47, 1236β1241, doi: 10.1038/ng.3406 (2015).26414676PMC4797329 | β | β | β |
| BurgessS. . Using published data in Mendelian randomization: a blueprint for efficient identification of causal risk factors. European journal of epidemiology 30, 543β552, doi: 10.1007/s10654-015-0011-z (2015).25773750PMC4516908 | β | β | β |
| CampionJ. & ChecinskiK. Smoking and mental health. (Royal College of Psychiatrists, 2013). | β | β | β |
| Coffee, . Genome-wide meta-analysis identifies six novel loci associated with habitual coffee consumption. Molecular psychiatry 20, 647β656, doi: 10.1038/mp.2014.107 (2015).25288136PMC4388784 | β | β | β |
| DalackG. W., HealyD. J. & Meador-WoodruffJ. H. Nicotine dependence in schizophrenia: clinical phenomena and laboratory findings. The American journal of psychiatry 155, 1490β1501 (1998).981210810.1176/ajp.155.11.1490 | β | β | β |
| de LeonJ. & DiazF. J. A meta-analysis of worldwide studies demonstrates an association between schizophrenia and tobacco smoking behaviors. Schizophrenia research 76, 135β157, doi: 10.1016/j.schres.2005.02.010 (2005).15949648 | β | β | β |
| DeppC. A. . Current smoking is associated with worse cognitive and adaptive functioning in serious mental illness. Acta psychiatrica Scandinavica 131, 333β341, doi: 10.1111/acps.12380 (2015).25559296PMC4400207 | β | β | β |
| DesaiH. D., SeaboltJ. & JannM. W. Smoking in patients receiving psychotropic medications: a pharmacokinetic perspective. CNS drugs 15, 469β494 (2001).1152402510.2165/00023210-200115060-00005 | β | β | β |
| GageS. H. & MunafoM. R. Rethinking the association between smoking and schizophrenia. Lancet Psychiatry 2, 118β119, doi: 10.1016/S2215-0366(14)00057-1 (2015).26359739 | β | β | β |
| GageS. H. . Associations of cannabis and cigarette use with psychotic experiences at age 18: findings from the Avon Longitudinal Study of Parents and Children. Psychological medicine 44, 3435β3444, doi: 10.1017/S0033291714000531 (2014).25066001PMC4255321 | β | β | β |
| GageS. H., Davey SmithG., WareJ. J., FlintJ. & MunafoM. R. G = E: What GWAS can tell us about the environment. PLoS Genet (2016).10.1371/journal.pgen.1005765PMC475085926866486 | β | β | β |
| GriffithJ. M. . Nicotinic receptor desensitization and sensory gating deficits in schizophrenia. Biological psychiatry 44, 98β106 (1998).964689110.1016/s0006-3223(97)00362-4 | β | β | β |
| GurilloP., JauharS., MurrayR. M. & MacCabeJ. H. Does tobacco use cause psychosis? Systematic review and meta-analysis. Lancet Psychiatry 2, 718β725, doi: 10.1016/S2215-0366(15)00152-2 (2015).26249303PMC4698800 | β | β | β |
| International HapMap, C. The International HapMap Project. Nature 426, 789β796, doi: 10.1038/nature02168 (2003).14685227 | β | β | β |
| JiaoH. . Genome wide association study identifies KCNMA1 contributing to human obesity. BMC medical genomics 4, 51, doi: 10.1186/1755-8794-4-51 (2011).21708048PMC3148553 | β | β | β |
| JonesH. J. . Phenotypic manifestation of genetic risk for schizophrenia during adolescence in the general population. JAMA psychiatry 73, 221β228 (2016).2681809910.1001/jamapsychiatry.2015.3058PMC5024747 | β | β | β |
| KendlerK. S., LonnS. L., SundquistJ. & SundquistK. Smoking and Schizophrenia in Population Cohorts of Swedish Women and Men: A Prospective Co-Relative Control Study. The American journal of psychiatry 172, 1092β1100, doi: 10.1176/appi.ajp.2015.15010126 (2015).26046339PMC4651774 | β | β | β |
| LevinE. D., WilsonW., RoseJ. E. & McEvoyJ. Nicotine-haloperidol interactions and cognitive performance in schizophrenics. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology 15, 429β436, doi: 10.1016/S0893-133X(96)00018-8 (1996).8914115 | β | β | β |
| LohrJ. B. & FlynnK. Smoking and schizophrenia. Schizophrenia research 8, 93β102 (1992).136081210.1016/0920-9964(92)90024-y | β | β | β |
| MarstonL., NazarethI., PetersenI., WaltersK. & OsbornD. P. Prescribing of antipsychotics in UK primary care: a cohort study. BMJ open 4, e006135, doi: 10.1136/bmjopen-2014-006135 (2014).PMC428153325524544 | β | β | β |
| MylesN. . Tobacco use before, at, and after first-episode psychosis: a systematic meta-analysis. The Journal of clinical psychiatry 73, 468β475, doi: 10.4088/JCP.11r07222 (2012).22579146 | β | β | β |
| PierceB. L. & BurgessS. Efficient design for Mendelian randomization studies: subsample and 2-sample instrumental variable estimators. American journal of epidemiology 178, 1177β1184, doi: 10.1093/aje/kwt084 (2013).23863760PMC3783091 | β | β | β |
| SalokangasR. K., HonkonenT., StengardE., KoivistoA. M. & HietalaJ. Cigarette smoking in long-term schizophrenia. European psychiatry : the journal of the Association of European Psychiatrists 21, 219β223, doi: 10.1016/j.eurpsy.2005.07.008 (2006).16360309 | β | β | β |
| Schizophrenia-Working-Group-of-the-Psychiatric-Genomics-Consortium. Biological insights from 108 schizophrenia-associated genetic loci. Nature 511, 421β427, doi: 10.1038/nature13595 (2014).25056061PMC4112379 | β | β | β |
| SieradzkaD. . Are genetic risk factors for psychosis also associated with dimension-specific psychotic experiences in adolescence? PLoS One 9, e94398, doi: 10.1371/journal.pone.0094398 (2014).24718684PMC3981778 | β | β | β |
| StaleyJ. R. . PhenoScanner: a database of human genotype-phenotype associations. Bioinformatics 32, 3207β3209, doi: 10.1093/bioinformatics/btw373 (2016).27318201PMC5048068 | β | β | β |
| ThorleifssonG. . Genome-wide association yields new sequence variants at seven loci that associate with measures of obesity. Nature genetics 41, 18β24, doi: 10.1038/ng.274 (2009).19079260 | β | β | β |
| Tobacco-and-Genetics-Consortium. Genome-wide meta-analyses identify multiple loci associated with smoking behavior. Nature genetics 42, 441β447, doi: 10.1038/ng.571 (2010).20418890PMC2914600 | β | β | β |
| WareJ. J., van den BreeM. B. & MunafoM. R. Association of the CHRNA5-A3-B4 gene cluster with heaviness of smoking: a meta-analysis. Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco 13, 1167β1175, doi: 10.1093/ntr/ntr118 (2011).22071378PMC3223575 | β | β | β |
| Wium-AndersenM. K., OrstedD. D. & NordestgaardB. G. Tobacco smoking is causally associated with antipsychotic medication use and schizophrenia, but not with antidepressant medication use or depression. International journal of epidemiology 44(2), 566β577, doi: 10.1093/ije/dyv090 (2015).26054357 | β | β | β |
| ZammitS. . Investigating the association between cigarette smoking and schizophrenia in a cohort study. The American journal of psychiatry 160, 2216β2221 (2003).1463859310.1176/appi.ajp.160.12.2216 | β | β | β |
| ZhangX. Y. . Gender difference in association of cognition with BDNF in chronic schizophrenia. Psychoneuroendocrinology 48, 136β146, doi: 10.1016/j.psyneuen.2014.06.004 (2014).24999831 | β | β | β |
In this knowledge base
| Title | Year | PMID |
|---|---|---|
| Meta-analysis of up to 622,409 individuals identifies 40 novel smoking behaviour associated genetic loci. | 2020 | 30617275 |
External
| Title | Authors | Journal | Year | Link |
|---|---|---|---|---|
| Associations of sleep patterns and genetic risk with risk of incident schizophrenia: A prospective cohort study of 294,856 participants. | Li S et al. | β | 2026 | β |
| The Effect of Smoking Cigarettes on the Progression of Psychotic Experiences to Psychotic Disorder: Evidence From a 6-Year Follow-Up Study. | GΓΌvercin E et al. | β | 2026 | β |
| Genetically Informed Study Highlights Income-Independent Effect of Schizophrenia Liability on Mental and Physical Health. | Kouakou MR et al. | β | 2024 | β |
| Physical Health and Transition to Psychosis in People at Clinical High Risk. | De Micheli A et al. | β | 2024 | β |
| Schizophrenia and Types of Stroke: AΒ Mendelian Randomization Study. | Nakada S et al. | β | 2024 | β |
| Schizophrenia mediating the effect of smoking phenotypes on antisocial behavior: A Mendelian randomization analysis. | Zhang M et al. | β | 2024 | β |
| Smoking as a mediator in the association between major depressive disorder and schizophrenia on lung cancer risk: a bidirectional/multivariable and mediation Mendelian randomization study. | Zhu X et al. | β | 2024 | β |
| Unravelling the complex causal effects of substance use behaviours on common diseases. | Xue A et al. | β | 2024 | β |
| Household income does not affect the pleiotropy of schizophrenia genetic liability with mental and physical health outcomes | Kouakou MR et al. | β | 2023 | β |
| Prevalence of tobacco smoking in people at clinical high-risk for psychosis: Systematic review and meta-analysis. | De Micheli A et al. | β | 2023 | β |
| Applications of Mendelian randomization in psychiatry: a comprehensive systematic review. | Saccaro LF et al. | β | 2022 | β |
| Associations Between Pregnancy-Related Predisposing Factors for Offspring Neurodevelopmental Conditions and Parental Genetic Liability to Attention-Deficit/Hyperactivity Disorder, Autism, and Schizophrenia: The Norwegian Mother, Father and Child Cohort Study (MoBa). | Havdahl A et al. | β | 2022 | β |
| Does smoking cause lower educational attainment and general cognitive ability? Triangulation of causal evidence using multiple study designs. | Gage SH et al. | β | 2022 | β |
| Evaluation of the causal relationship between smoking and schizophrenia in East Asia. | Su MH et al. | β | 2022 | β |
| Genetic correlation, pleiotropy, and causal associations between substance use and psychiatric disorder. | Jang SK et al. | β | 2022 | β |
| Cigarette Smoking and Schizophrenia: Etiology, Clinical, Pharmacological, and Treatment Implications. | Ding JB et al. | β | 2021 | β |
| Cigarette smoking and schizophrenia: Mendelian randomisation study. | Chen J et al. | β | 2021 | β |
| Cigarette smoking as a risk factor for schizophrenia or all non-affective psychoses. | King M et al. | β | 2021 | β |
| Computational Tools for Causal Inference in Genetics. | Richardson TG et al. | β | 2021 | β |
| Genetics of substance use disorders in the era of big data. | Gelernter J et al. | β | 2021 | β |
| Genome-wide analyses of smoking behaviors in schizophrenia: Findings from the Psychiatric Genomics Consortium. | Peterson RE et al. | β | 2021 | β |
| Shared Genetic Background between Parkinson's Disease and Schizophrenia: A Two-Sample Mendelian Randomization Study. | Kim K et al. | β | 2021 | β |
| The Association between Lifestyle Choices and Schizophrenia Symptoms. | Kalinowska S et al. | β | 2021 | β |
| Using Mendelian randomization analysis to better understand the relationship between mental health and substance use: a systematic review. | Treur JL et al. | β | 2021 | β |
| A meta-review of "lifestyle psychiatry": the role of exercise, smoking, diet and sleep in the prevention and treatment of mental disorders. | Firth J et al. | β | 2020 | β |
| Evidence for causal effects of lifetime smoking on risk for depression and schizophrenia: a Mendelian randomisation study. | Wootton RE et al. | β | 2020 | β |
| Sleep Duration and Stroke: A Mendelian Randomization Study. | Lu H et al. | β | 2020 | β |
| Statin-induced LDL cholesterol response and type 2 diabetes: a bidirectional two-sample Mendelian randomization study. | Smit RAJ et al. | β | 2020 | β |
| Cigarette smoking and personality: interrogating causality using Mendelian randomisation. | Sallis HM et al. | β | 2019 | β |
| Evidence of a causal relationship between body mass index and psoriasis: A mendelian randomization study. | Budu-Aggrey A et al. | β | 2019 | β |
| Nicotine consumption during the prodromal phase of schizophrenia - a review of the literature. | Gogos A et al. | β | 2019 | β |
| Schizophrenia risk and reproductive success: a Mendelian randomization study. | Lawn RB et al. | β | 2019 | β |
| Sleep duration and risk of diabetes: Observational and Mendelian randomization studies. | Wang J et al. | β | 2019 | β |
| The relationship between nicotine and psychosis. | Quigley H et al. | β | 2019 | β |
| Association of Combined Patterns of Tobacco and Cannabis Use in Adolescence With Psychotic Experiences. | Jones HJ et al. | β | 2018 | β |
| Cigarette Smoking by Patients With Serious Mental Illness, 1999-2016: An Increasing Disparity. | Dickerson F et al. | β | 2018 | β |
| Genome-wide interaction study of a proxy for stress-sensitivity and its prediction of major depressive disorder. | Arnau-Soler A et al. | β | 2018 | β |
| Identification of shared genetic variants between schizophrenia and lung cancer. | Zuber V et al. | β | 2018 | β |
| Reducing Smoking Among People With Schizophrenia: Perspectives on Priorities for Advancing Research. | Baker AL et al. | β | 2018 | β |
| Smokin' hot: adolescent smoking and the risk of psychosis. | Mustonen A et al. | β | 2018 | β |
| Tobacco Use Decreases Visual Sensitivity in Schizophrenia. | Fernandes TMP et al. | β | 2018 | β |
| Polygenic Risk Scores in Psychiatry. | Goldman D | β | 2017 | β |