Gustaf Rejnö1, Cecilia Lundholm2, Kjell Larsson3, Henrik Larsson2, Paul Lichtenstein2, Brian M D'Onofrio4, Sissel Saltvedt5, Catarina Almqvist6. 1. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; Obstetrics & Gynaecology Unit, Södersjukhuset, Stockholm, Sweden. Electronic address: gustaf.rejno@ki.se. 2. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. 3. Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden. 4. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; Department of Psychological and Brain Sciences, Indiana University, Bloomington, Ind. 5. Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet, Stockholm, Sweden; Obstetrics & Gynaecology Unit, Karolinska University Hospital, Stockholm, Sweden. 6. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; Unit of Pediatric Allergy and Pulmonology, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden.
Abstract
BACKGROUND: Asthma is associated with several adverse pregnancy and perinatal outcomes. Familial factors may confound these associations. OBJECTIVE: To examine the role of measured and unmeasured confounding by conducting a study that compared differentially exposed cousins and siblings from the same families. METHODS: We retrieved data on adverse pregnancy outcomes, prescribed drugs, and physician-diagnosed asthma from nationwide registers for all women in Sweden with singleton births between 2001 and 2013. Logistic and linear regression estimated the association between maternal asthma and several outcomes in the whole population and within differently exposed pregnant relatives. RESULTS: In total, 1,075,153 eligible pregnancies were included and 10.1% of the study population had asthma. We identified 475,200 cousin and 341,205 sister pregnancies. Women with asthma had increased risks for preeclampsia (adjusted odds ratio [aOR], 1.17; 95% CI, 1.13-1.21), emergency cesarean section (aOR, 1.24; 95% CI, 1.22-1.27), and having a child small for gestational age (aOR, 1.18; 95% CI, 1.12-1.23). In the conditional regression analyses, after adjustment for familial factors, the associations remained: preeclampsia in cousins (aOR, 1.16; 95% CI, 1.07-1.25) and siblings (aOR, 1.23; 95% CI, 1.08-1.38), emergency cesarean section in cousins (aOR, 1.28) and siblings (aOR, 1.21), and small for gestational age in cousins (aOR, 1.17) and siblings (aOR, 1.13). CONCLUSIONS: Factors shared by siblings and cousins do not seem to explain the observed association between maternal asthma and adverse pregnancy outcomes. This implies that targeting the asthma disease will continue to be important in reducing risks for adverse outcomes in pregnancy.
BACKGROUND:Asthma is associated with several adverse pregnancy and perinatal outcomes. Familial factors may confound these associations. OBJECTIVE: To examine the role of measured and unmeasured confounding by conducting a study that compared differentially exposed cousins and siblings from the same families. METHODS: We retrieved data on adverse pregnancy outcomes, prescribed drugs, and physician-diagnosed asthma from nationwide registers for all women in Sweden with singleton births between 2001 and 2013. Logistic and linear regression estimated the association between maternal asthma and several outcomes in the whole population and within differently exposed pregnant relatives. RESULTS: In total, 1,075,153 eligible pregnancies were included and 10.1% of the study population had asthma. We identified 475,200 cousin and 341,205 sister pregnancies. Women with asthma had increased risks for preeclampsia (adjusted odds ratio [aOR], 1.17; 95% CI, 1.13-1.21), emergency cesarean section (aOR, 1.24; 95% CI, 1.22-1.27), and having a child small for gestational age (aOR, 1.18; 95% CI, 1.12-1.23). In the conditional regression analyses, after adjustment for familial factors, the associations remained: preeclampsia in cousins (aOR, 1.16; 95% CI, 1.07-1.25) and siblings (aOR, 1.23; 95% CI, 1.08-1.38), emergency cesarean section in cousins (aOR, 1.28) and siblings (aOR, 1.21), and small for gestational age in cousins (aOR, 1.17) and siblings (aOR, 1.13). CONCLUSIONS: Factors shared by siblings and cousins do not seem to explain the observed association between maternal asthma and adverse pregnancy outcomes. This implies that targeting the asthma disease will continue to be important in reducing risks for adverse outcomes in pregnancy.
Authors: Hooman Mirzakhani; Vincent J Carey; Thomas F McElrath; Weiliang Qiu; Bruce W Hollis; George T O'Connor; Robert S Zeiger; Leonard Bacharier; Augusto A Litonjua; Scott T Weiss Journal: Am J Respir Crit Care Med Date: 2019-01-01 Impact factor: 30.528
Authors: Gustaf Rejnö; Cecilia Lundholm; Sara Öberg; Paul Lichtenstein; Henrik Larsson; Brian D'Onofrio; Kjell Larsson; Sissel Saltvedt; Bronwyn K Brew; Catarina Almqvist Journal: Sci Rep Date: 2019-09-11 Impact factor: 4.379
Authors: Mari Kemppainen; Anna-Maria Lahesmaa-Korpinen; Paula Kauppi; Martti Virtanen; Suvi M Virtanen; Riitta Karikoski; Mika Gissler; Turkka Kirjavainen Journal: PLoS One Date: 2018-05-18 Impact factor: 3.240