| 1. |
- Quinn, Patrick D., et al.
(författare)
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Association Between Maternal Smoking During Pregnancy and Severe Mental Illness in Offspring
- 2017
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Ingår i: JAMA psychiatry. - : American Medical Association. - 2168-6238 .- 2168-622X. ; 74:6, s. 589-596
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Tidskriftsartikel (refereegranskat)abstract
- IMPORTANCE: Several recent population-based studies have linked exposure to maternal smoking during pregnancy to increased risk of severe mental illness in offspring (eg, bipolar disorder, schizophrenia). It is not yet clear, however, whether this association results from causal teratogenic effects or from confounding influences shared by smoking and severe mental illness.OBJECTIVE: To examine the association between smoking during pregnancy and severe mental illness in offspring, adjusting for measured covariates and unmeasured confounding using family-based designs.DESIGN, SETTING, AND PARTICIPANTS: This study analyzed population register data through December 31, 2013, for a cohort of 1 680 219 individuals born in Sweden from January 1, 1983, to December 31, 2001. Associations between smoking during pregnancy and severe mental illness in offspring were estimated with adjustment for measured covariates. Cousins and siblings who were discordant on smoking during pregnancy and severe mental illness were then compared, which helped to account for unmeasured genetic and environmental confounding by design.EXPOSURES: Maternal self-reported smoking during pregnancy, obtained from antenatal visits.MAIN OUTCOMES AND MEASURES: Severe mental illness, with clinical diagnosis obtained from inpatient and outpatient visits and defined using International Classification of Diseases codes for bipolar disorder and schizophrenia spectrum disorders.RESULTS: Of the 1 680 219 offspring included in the analysis, 816 775 (48.61%) were female. At the population level, offspring exposed to moderate and high levels of smoking during pregnancy had greater severe mental illness rates than did unexposed offspring (moderate smoking during pregnancy: hazard ratio [HR], 1.25; 95% CI, 1.19-1.30; high smoking during pregnancy: HR, 1.51; 95% CI, 1.44-1.59). These associations decreased in strength with increasing statistical and methodologic controls for familial confounding. In sibling comparisons with within-family covariates, associations were substantially weaker and nonsignificant (moderate smoking during pregnancy: HR, 1.09; 95% CI, 0.94-1.26; high smoking during pregnancy: HR, 1.14; 95% CI, 0.96-1.35). The pattern of associations was consistent across subsets of severe mental illness disorders and was supported by further sensitivity analyses.CONCLUSIONS AND RELEVANCE: This population-and family-based study failed to find support for a causal effect of smoking during pregnancy on risk of severe mental illness in offspring. Rather, these results suggest that much of the observed population-level association can be explained by measured and unmeasured factors shared by siblings.
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| 2. |
- Barboza, F. R., et al.
(författare)
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Geographic variation in fitness-related traits of the bladderwrack Fucus vesiculosus along the Baltic Sea-North Sea salinity gradient
- 2019
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 9:16, s. 9225-9238
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Tidskriftsartikel (refereegranskat)abstract
- In the course of the ongoing global intensification and diversification of human pressures, the study of variation patterns of biological traits along environmental gradients can provide relevant information on the performance of species under shifting conditions. The pronounced salinity gradient, co-occurrence of multiple stressors, and accelerated rates of change make the Baltic Sea and its transition to North Sea a suitable region for this type of study. Focusing on the bladderwrack Fucus vesiculosus, one of the main foundation species on hard-bottoms of the Baltic Sea, we analyzed the phenotypic variation among populations occurring along 2,000km of coasts subjected to salinities from 4 to >30 and a variety of other stressors. Morphological and biochemical traits, including palatability for grazers, were recorded at 20 stations along the Baltic Sea and four stations in the North Sea. We evaluated in a common modeling framework the relative contribution of multiple environmental drivers to the observed trait patterns. Salinity was the main and, in some cases, the only environmental driver of the geographic trait variation in F.vesiculosus. The decrease in salinity from North Sea to Baltic Sea stations was accompanied by a decline in thallus size, photosynthetic pigments, and energy storage compounds, and affected the interaction of the alga with herbivores and epibiota. For some traits, drivers that vary locally such as wave exposure, light availability or nutrient enrichment were also important. The strong genetic population structure in this macroalgae might play a role in the generation and maintenance of phenotypic patterns across geographic scales. In light of our results, the desalination process projected for the Baltic Sea could have detrimental impacts on F.vesiculosus in areas close to its tolerance limit, affecting ecosystem functions such as habitat formation, primary production, and food supply.
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| 3. |
- Class, Quetzal A., et al.
(författare)
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Fetal growth and psychiatric and socioeconomic problems : population-based sibling comparison
- 2014
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Ingår i: British Journal of Psychiatry. - London, United Kingdom : Royal College od Psychiatrists. - 0007-1250 .- 1472-1465. ; 205:5, s. 355-361
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Tidskriftsartikel (refereegranskat)abstract
- Background: It is unclear whether associations between fetal growth and psychiatric and socioeconomic problems are consistent with causal mechanisms.Aims: To estimate the extent to which associations are a result of unmeasured confounding factors using a sibling-comparison approach.Method: We predicted outcomes from continuously measured birth weight in a Swedish population cohort (n = 3 291 773), while controlling for measured and unmeasured confounding.Results: In the population, lower birth weight (⩽ 2500 g) increased the risk of all outcomes. Sibling-comparison models indicated that lower birth weight independently predicted increased risk for autism spectrum disorder (hazard ratio for low birth weight = 2.44, 95% CI 1.99-2.97) and attention-deficit hyperactivity disorder. Although attenuated, associations remained for psychotic or bipolar disorder and educational problems. Associations with suicide attempt, substance use problems and social welfare receipt, however, were fully attenuated in sibling comparisons.Conclusions: Results suggest that fetal growth, and factors that influence it, contribute to psychiatric and socioeconomic problems.
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| 4. |
- Class, Quetzal A., et al.
(författare)
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Outcome-dependent associations between short interpregnancy interval and offspring psychological and educational problems : a population-based quasi-experimental study
- 2018
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Ingår i: International Journal of Epidemiology. - Stockholm : Oxford University Press. - 0300-5771 .- 1464-3685. ; 47:4, s. 1159-1168
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Tidskriftsartikel (refereegranskat)abstract
- Background: Causal interpretation of associations between short interpregnancy interval (the duration from the preceeding birth to the conception of the next-born index child) and the offspring's psychological and educational problems may be influenced by a failure to account for unmeasured confounding.Methods: Using population-based Swedish data from 1973-2009, we estimated the association between interpregnancy interval and outcomes [autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), severe mental illness, suicide attempt, criminality, substance-use problem and failing grades] while controlling for measured covariates. We then used cousin comparisons, post-birth intervals (the interval between the second-and third-born siblings to predict second-born outcomes) and sibling comparisons to assess the influence of unmeasured confounding. We included an exploratory analysis of long interpregnancy interval.Results: Interpregnancy intervals of 0-5 and 6-11 months were associated with higher odds of outcomes in cohort analyses. Magnitudes of association were attenuated following adjustment for measured covariates. Associations were eliminated for ADHD, severe mental illness and failing grades, but maintained magnitude for ASD, suicide attempt, criminality and substance-use problem in cousin comparisons. Post-birth interpregnancy interval and sibling comparisons suggested some familial confounding. Associations did not persist across models of long interpregnancy interval.Conclusions: Attenuation of the association in cousin comparisons and comparable post-birth interval associations suggests that familial genetic or environmental confounding accounts for a majority of the association for ADHD, severe mental illness and failing grades. Modest associations appear independently of covariates for ASD, suicide attempt, criminality and substance-use problem. Post-birth analyses and sibling comparisons, however, show some confounding in these associations.
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| 5. |
- D'Onofrio, Brian M., et al.
(författare)
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Familial confounding of the association between maternal smoking during pregnancy and offspring substance use and problems
- 2012
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Ingår i: Archives of General Psychiatry. - Chicago, USA : American Medical Association. - 0003-990X .- 1538-3636. ; 69:11, s. 1140-1150
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Tidskriftsartikel (refereegranskat)abstract
- Context: Previous epidemiological, animal, and human cognitive neuroscience research suggests that maternal smoking during pregnancy (SDP) causes increased risk of substance use/problems in offspring.Objective: To determine the extent to which the association between SDP and offspring substance use/problems depends on confounded familial background factors by using a quasi-experimental design.Design: We used 2 separate samples from the United States and Sweden. The analyses prospectively predicted multiple indices of substance use and problems while controlling for statistical covariates and comparing differentially exposed siblings to minimize confounding.Setting: Offspring of a representative sample of women in the United States (sample 1) and the total Swedish population born during the period from January 1, 1983, to December 31, 1995 (sample 2).Patients or Other Participants: Adolescent offspring of the women in the National Longitudinal Survey of Youth 1979 (n = 6904) and all offspring born in Sweden during the 13-year period (n = 1,187,360).Main Outcome Measures: Self-reported adolescent alcohol, cigarette, and marijuana use and early onset (before 14 years of age) of each substance (sample 1) and substance-related convictions and hospitalizations for an alcohol- or other drug-related problem (sample 2).Results: The same pattern emerged for each index of substance use/problems across the 2 samples. At the population level, maternal SDP predicted every measure of offspring substance use/problems in both samples, ranging from adolescent alcohol use (hazard ratio [HR](moderate), 1.32 [95% CI, 1.22-1.43]; HR(high), 1.33 [1.17-1.53]) to a narcotics-related conviction (HR(moderate), 2.23 [2.14-2.31]; HR(high), 2.97 [2.86-3.09]). When comparing differentially exposed siblings to minimize genetic and environmental confounds, however, the association between SDP and each measure of substance use/problems was minimal and not statistically significant.Cocnlusions: The association between maternal SDP and offspring substance use/problems is likely due to familial background factors, not a causal influence, because siblings have similar rates of substance use and problems regardless of their specific exposure to SDP.
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| 6. |
- D'Onofrio, Brian M., et al.
(författare)
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Paternal age at childbearing and offspring psychiatric and academic morbidity
- 2014
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Ingår i: JAMA psychiatry. - Chicago, United States : American Medical Association. - 2168-6238 .- 2168-622X. ; 71:4, s. 432-438
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Tidskriftsartikel (refereegranskat)abstract
- Importance: Advancing paternal age is associated with increased genetic mutations during spermatogenesis, which research suggests may cause psychiatric morbidity in the offspring. The effects of advancing paternal age at childbearing on offspring morbidity remain unclear, however, because of inconsistent epidemiologic findings and the inability of previous studies to rigorously rule out confounding factors.Objective: To examine the associations between advancing paternal age at childbearing and numerous indexes of offspring morbidity.Design, setting and participants: We performed a population-based cohort study of all individuals born in Sweden in 1973-2001 (N = 2,615,081), with subsets of the data used to predict childhood or adolescent morbidity. We estimated the risk of psychiatric and academic morbidity associated with advancing paternal age using several quasi-experimental designs, including the comparison of differentially exposed siblings, cousins, and first-born cousins.Exposure: Paternal age at childbearing.Main outcomes and measures: Psychiatric (autism, attention-deficit/hyperactivity disorder, psychosis, bipolar disorder, suicide attempt, and substance use problem) and academic (failing grades and low educational attainment) morbidity.Results: In the study population, advancing paternal age was associated with increased risk of some psychiatric disorders (eg, autism, psychosis, and bipolar disorders) but decreased risk of the other indexes of morbidity. In contrast, the sibling-comparison analyses indicated that advancing paternal age had a dose-response relationship with every index of morbidity, with the magnitude of the associations being as large or larger than the estimates in the entire population. Compared with offspring born to fathers 20 to 24 years old, offspring of fathers 45 years and older were at heightened risk of autism (hazard ratio [HR] = 3.45; 95% CI, 1.62-7.33), attention-deficit/hyperactivity disorder (HR = 13.13; 95% CI, 6.85-25.16), psychosis (HR = 2.07; 95% CI, 1.35-3.20), bipolar disorder (HR = 24.70; 95% CI, 12.12-50.31), suicide attempts (HR = 2.72; 95% CI, 2.08-3.56), substance use problems (HR = 2.44; 95% CI, 1.98-2.99), failing a grade (odds ratio [OR] = 1.59; 95% CI, 1.37-1.85), and low educational attainment (OR = 1.70; 95% CI, 1.50-1.93) in within-sibling comparisons. Additional analyses using several quasi-experimental designs obtained commensurate results, further strengthening the internal and external validity of the findings.Conclusions and relevance: Advancing paternal age is associated with increased risk of psychiatric and academic morbidity, with the magnitude of the risks being as large or larger than previous estimates. These findings are consistent with the hypothesis that new genetic mutations that occur during spermatogenesis are causally related to offspring morbidity.
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| 7. |
- D'Onofrio, Brian M., et al.
(författare)
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Preterm birth and mortality and morbidity : a population-based quasi-experimental study
- 2013
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Ingår i: JAMA psychiatry. - Chicago, USA : American Medical Association. - 2168-6238 .- 2168-622X. ; 70:11, s. 1231-1240
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Tidskriftsartikel (refereegranskat)abstract
- Importance: Preterm birth is associated with increased mortality and morbidity. However, previous studies have been unable to rigorously examine whether confounding factors cause these associations rather than the harmful effects of being born preterm.Objective: To estimate the extent to which the associations between early gestational age and offspring mortality and morbidity are the result of confounding factors by using a quasi-experimental design, the sibling-comparison approach, and by controlling for statistical covariates that varied within families.Design, setting and participants: A population-based cohort study, combining Swedish registries to identify all individuals born in Sweden from 1973 to 2008 (3,300,708 offspring of 1,736,735 mothers) and link them with multiple outcomes.Main outcomes and measures: Offspring mortality (during infancy and throughout young adulthood) and psychiatric (psychotic or bipolar disorder, autism, attention-deficit/hyperactivity disorder, suicide attempts, substance use, and criminality), academic (failing grades and educational attainment), and social (partnering, parenthood, low income, and social welfare benefits) outcomes through 2009.Results: In the population, there was a dose-response relationship between early gestation and the outcome measures. For example, extreme preterm birth (23-27 weeks of gestation) was associated with infant mortality (odds ratio, 288.1; 95% CI, 271.7-305.5), autism (hazard ratio [HR], 3.2; 95% CI, 2.6-4.0), low educational attainment (HR, 1.7; 1.5-2.0), and social welfare benefits (HR, 1.3; 1.2-1.5) compared with offspring born at term. The associations between early gestation and mortality and psychiatric morbidity generally were robust when comparing differentially exposed siblings and controlling for statistical covariates, whereas the associations with academic and some social problems were greatly or completely attenuated in the fixed-effects models.Conclusions and relevance: The mechanisms responsible for the associations between preterm birth and mortality and morbidity are outcome-specific. Associations between preterm birth and mortality and psychiatric morbidity are largely independent of shared familial confounds and measured covariates, consistent with a causal inference. However, some associations, particularly predicting suicide attempt, educational attainment, and social welfare benefits, are the result of confounding factors. The findings emphasize the importance of both reducing preterm birth and providing wraparound services to all siblings in families with an offspring born preterm.
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| 8. |
- D'Onofrio, Brian M., et al.
(författare)
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Translational Epidemiologic Approaches to Understanding the Consequences of Early-Life Exposures
- 2016
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Ingår i: Behavior Genetics. - New York, USA : Springer. - 0001-8244 .- 1573-3297. ; 46:3, s. 315-328
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Forskningsöversikt (refereegranskat)abstract
- Prominent developmental theories posit a causal link between early-life exposures and later functioning. Yet, observed associations with early exposures may not reflect causal effects because of genetic and environmental confounding. The current manuscript describes how a systematic series of epidemiologic analyses that combine several genetically-informative designs and statistical approaches can help distinguish between competing theories. In particular, the manuscript details how combining the use of measured covariates with sibling-comparisons, cousin-comparisons, and additional designs can help elucidate the sources of covariation between early-life exposures and later outcomes, including the roles of (a) factors that are not shared in families, including a potential causal effect of the exposure; (b) carryover effects from the exposure of one child to the next; and (c) familial confounding. We also describe key assumptions and how they can be critically evaluated. Furthermore, we outline how subsequent analyses, including effect decomposition with respect to measured, plausible mediators, and quantitative genetic models can help further specify the underlying processes that account for the associations between early-life exposures and offspring outcomes.
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| 9. |
- Fine, Kimberly L., et al.
(författare)
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Association Between Early Prescribed Opioid Initiation and Risk of Suicidal Behavior
- 2020
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Prescription opioid use has been linked to increased risk of suicidal behavior in adults. However, little research exists examining the role of prescription opioid use on risk of suicidal behavior in children and adolescents. This population is at high risk for suicidal behavior, as suicide is the second leading cause of death for people ages 10 to 34. Using healthcare data from Swedish population registers, we aimed to characterize the extent to which exposure to opioids at a young age leads to an increased risk of new onset suicidal behavior, for those with no history of suicidal behavior. Compared to demographically matched non-recipients, young people who initiated prescription opioids had just under three times the rate of subsequent suicidal behavior (HR = 2.64, 95% CI, 2.47-2.81). Compared to their unexposed siblings, young people who initiated prescription opioids had roughly two times the rate of subsequent suicidal behavior (HR = 1.83, 95% CI, 1.67-2.01). Finally, compared to young people initiating prescription NSAIDs, young people who initiated prescription opioids had only 19% relatively greater rates of suicidal behavior (HR, 1.19, 95% CI, 1.11-1.27). These results suggest the association between prescription opioids and suicidal behavior may be driven by the underlying pain indication.
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| 10. |
- Fine, Kimberly L., et al.
(författare)
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Initiation of Opioid Prescription and Risk of Suicidal Behavior Among Youth and Young Adults
- 2022
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Ingår i: Pediatrics. - : American Academy of Pediatrics. - 0031-4005 .- 1098-4275. ; 149:3
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND OBJECTIVES: Opioids are involved in an increasing proportion of suicide deaths. This study examined the association between opioid analgesic prescription initiation and suicidal behavior among young people.METHODS: We analyzed Swedish population-register data on 1 895 984 individuals ages 9 to 29 years without prior recorded opioid prescriptions. We identified prescriptions dispensed from January 2007 onward and diagnosed self-injurious behavior and death by suicide through December 2013. We first compared initiators with demographically matched noninitiators. To account for confounding, we applied an active comparator design, which examined suicidal behavior among opioid initiators relative to prescription nonsteroidal antiinflammatory drug (NSAID) initiators while inverse-probability-of-treatment weighting with individual and familial covariates.RESULTS: Among the cohort, 201 433 individuals initiated opioid prescription. Relative to demographically matched noninitiators, initiators (N = 180 808) had more than doubled risk of incident suicidal behavior (hazard ratio = 2.64; 95% confidence interval [CI], 2.47-2.81). However, in the active comparator design, opioid initiators (N = 86 635) had only 19% relatively greater risk of suicidal behavior compared with NSAID initiators (N = 255 096; hazard ratio = 1.19; 95% CI,: 1.11-1.28), corresponding to a weighted 5-year cumulative incidence of 2.2% (95% CI, 2.1-2.4) for opioid and 1.9% (95% CI, 1.9-2.0) for NSAID initiators. Most sensitivity analyses produced comparable results.CONCLUSIONS: Opioid initiation may make only a small contribution to the elevated risk of suicidal behavior among young people receiving pharmacologic pain management. In weighing benefits and harms of opioid initiation, our results suggest that increased risk of suicidal behavior may not be a major concern.
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