Alcohol-related morbidity and mortality by fathers' parental leave: A quasi-experimental study in Sweden

BACKGROUND AND AIMS

Fathers' parental leave has been associated with decreased risks of alcohol-related hospitalizations and mortality. Whether this is attributable to the health protections of parental leave itself (through stress reduction or behavioral changes) or to selection into leave uptake remains unclear, given that fathers are more likely to use leave if they are in better health. Using the quasi-experimental variation of a reform incentivizing fathers' leave uptake (the 1995 Father's quota reform), this study aimed to assess whether fathers' parental leave influences alcohol-related morbidity and mortality.

DESIGN

Quasi-experimental interrupted time series and instrumental variable analyses.

SETTING

Sweden.

PARTICIPANTS

Fathers of singleton children born from January 1992 to December 1997 (n = 220 412).

MEASUREMENTS

Exposure was indicated by the child's birthdate before or after the reform and used to instrument fathers' 2- and 8-year parental leave uptake. Outcomes included fathers' hospitalization rates for acute alcohol-related (intoxication; mental and behavioral disorders) and chronic alcohol-related diagnoses (cardiovascular, stomach and other diseases; liver diseases), as well as alcohol-related mortality, up to 2, 8 and 18 years after the first child's birthdate.

FINDINGS

In interrupted time series analyses, fathers of children born after the reform exhibited immediate decreases in alcohol-related hospitalization rates up to 2 (incidence rate ratio [IRR] = 0.66, 95% confidence interval [CI] = 0.51-0.87), 8 (IRR = 0.74, 95% CI = 0.57-0.96) and 18 years after birth (IRR = 0.72, 95% CI = 0.54-0.96), particularly in acute alcohol-related hospitalization rates, compared with those with children born before. No changes were found for alcohol-related mortality. Instrumental variable results suggest that alcohol-related hospitalization decreases were driven by fathers' parental leave uptake (e.g. 2-year hospitalizations: IRR = 0.16, 95% CI = 0.03-0.84).

CONCLUSIONS

In Sweden, a father's parental leave eligibility and uptake may protect against alcohol-related morbidity.

Mental health by native–immigrant intermarriage in Sweden: a register-based retrospective cohort study

Background

Native–immigrant intermarriage is often regarded as a proxy for integration, given that intermarried immigrants are more socioeconomically and culturally similar to natives than intramarried immigrants. This study aimed to assess whether integration affects mental health and care-seeking behaviours, examining prescription hazards for psychotropic medications by native–immigrant marital composition in Sweden.

Methods

Total population register data were used to identify first-time married couples residing in Sweden between 31 December 2005 and 31 December 2016. Index persons were distinguished by gender and partners’ origin (native vs. immigrant), as well as by immigrants’ regions of origin, with intramarried natives as references. Using Cox regression, hazard ratios (HRs) with 95% confidence intervals (95% CIs) were calculated for antidepressant and anxiolytic prescriptions and adjusted for socioeconomic factors, presence of children and length and quality of marriage.

Results

Intramarried immigrant women had higher psychotropic prescription hazards than intramarried native references (HR 1.11, 95% CI 1.10–1.12), whereas intermarried immigrant women had equal hazards. Immigrant women’s hazards were lower than native references after adjustment. Intramarried immigrant men had the greatest prescription hazards (HR 1.33, 95% CI 1.32–1.34), and intermarried immigrant men slightly higher hazards (HR 1.11, 95% CI 1.10–1.13), than intramarried natives. All were partly attenuated after adjustment. Intermarriage hazards increased by similarities in regions of origin, especially among men.

Conclusions

Integration indicated by intermarriage appears to be protective for the mental health of immigrants, especially for immigrant men. Future research should empirically disentangle the social, cultural and socioeconomic mechanisms underlying these health differences.

Intermarriage and COVID-19 mortality among immigrants. A population-based cohort study from Sweden

OBJECTIVES

To evaluate the role of language proficiency and institutional awareness in explaining excess COVID-19 mortality among immigrants.

DESIGN

Cohort study with follow-up between 12 March 2020 and 23 February 2021.

SETTING

Swedish register-based study on all residents in Sweden.

PARTICIPANTS

3 963 356 Swedish residents in co-residential unions who were 30 years of age or older and alive on 12 March 2020 and living in Sweden in December 2019.

OUTCOME MEASURES

Cox regression models were conducted to assess the association between different constellations of immigrant-native couples (proxy for language proficiency and institutional awareness) and COVID-19 mortality and all other causes of deaths (2019 and 2020). Models were adjusted for relevant confounders.

RESULTS

Compared with Swedish-Swedish couples (1.18 deaths per thousand person-years), both immigrants partnered with another immigrant and a native showed excess mortality for COVID-19 (HR 1.43; 95% CI 1.29 to 1.58 and HR 1.24; 95% CI 1.10 to 1.40, respectively), which translates to 1.37 and 1.28 deaths per thousand person-years. Moreover, similar results are found for natives partnered with an immigrant (HR 1.15; 95% CI 1.02 to 1.29), which translates to 1.29 deaths per thousand person-years. Further analysis shows that immigrants from both high-income and low-income and middle-income countries (LMIC) experience excess mortality also when partnered with a Swede. However, having a Swedish-born partner is only partially protective against COVID-19 mortality among immigrants from LMIC origins.

CONCLUSIONS

Language barriers and/or poor institutional awareness are not major drivers for the excess mortality from COVID-19 among immigrants. Rather, our study provides suggestive evidence that excess mortality among immigrants is explained by differential exposure to the virus.

Psychological distress by age at migration and duration of residence in Sweden

Migrants suffer from worse psychological health than natives in many countries, yet the extent to which this varies by age at migration and duration of residence in the receiving context remains unexplored in Sweden. Drawing on a life course approach, we investigate differences in psychological distress by age at migration and duration of residence in working-age migrants to Sweden, and examine the role of various social determinants of health in explaining these differences relative to Swedish-born. Using pooled cross-sectional data from the 2011/2015 Health on Equal Terms survey in Västra Götaland Region, Sweden (n = 58,428), we applied logistic regression analysis to calculate predicted probabilities and average marginal effects (AME) of migrant status, by age at migration and duration of residence, on psychological distress. Analyses were stratified by sex and region of origin and controlled for indicators of socioeconomic status (SES), social cohesion, and discrimination to assess their potential contribution to differences in migrants' and natives' psychological distress. All migrants except men from OECD-predominant regions had a greater probability of psychological distress than Swedish-born (ranging from AME 0.031 [95% Confidence Interval or CI 0.000-0.062] for OECD women to AME 0.115 [95% CI 0.074-0.156] for non-OECD men). Marginal effects of migration status on psychological distress probabilities generally increased with age at migration and duration of residence. Differences between migrants and natives were largely attenuated after controlling for social determinants, the greatest contribution coming from inequalities in social cohesion, followed by inequalities in discrimination and SES. Our results suggest a relative health advantage of early-life compared to later-life migration, albeit with worse outcomes with longer residence in Sweden. The predominance of integration opportunities in childhood strengthens calls for supportive policies to assist older migrants' integration directly upon arrival, which may ultimately improve their psychological wellbeing.

Acculturation or unequal assimilation? Smoking during pregnancy and duration of residence among migrants in Sweden

A growing corpus of evidence reveals that smoking patterns of migrant women tend to converge with that of the host population over time ('acculturation paradox'). In this paper we aim to adopt a health equity perspective by studying the extent to which this pattern reflects a convergence with the group of natives who are more socioeconomically disadvantaged. Using population-based registers, we study 1,194,296 women who gave birth in Sweden between 1991 and 2012. Using logistic regression, we estimated odds ratios to assess the effect of duration of residence on the association between smoking during pregnancy and women's origin (classified according to inequality-adjusted Human Development Index (iHDI) of the country of birth). Sibling information and multilevel models were used to assess the extent to which our results might be affected by the cross-sectional nature of the data. Smoking during pregnancy increases with duration of residence among migrants from all levels of iHDI to such an extent that they tend to converge or increase in relation to the levels of the Swedish population with low education and low income, leaving behind the native population with high education and income. The results are robust to possible selection bias related to the cross-sectional nature of the data. Our findings indicate the need of a health equity perspective and suggest the use of 'unequal assimilation' rather than 'acculturation paradox' as a more suitable framework to interpret these findings.

Effects of non-health-targeted policies on migrant health: a systematic review and meta-analysis

BACKGROUND

Government policies can strongly influence migrants' health. Using a Health in All Policies approach, we systematically reviewed evidence on the impact of public policies outside of the health-care system on migrant health.

METHODS

We searched the PubMed, Embase, and Web of Science databases from Jan 1, 2000, to Sept 1, 2017, for quantitative studies comparing the health effects of non-health-targeted public policies on migrants with those on a relevant comparison population. We searched for articles written in English, Swedish, Danish, Norwegian, Finnish, French, Spanish, or Portuguese. Qualitative studies and grey literature were excluded. We evaluated policy effects by migration stage (entry, integration, and exit) and by health outcome using narrative synthesis (all included studies) and random-effects meta-analysis (all studies whose results were amenable to statistical pooling). We summarised meta-analysis outcomes as standardised mean difference (SMD, 95% CI) or odds ratio (OR, 95% CI). To assess certainty, we created tables containing a summary of the findings according to the Grading of Recommendations Assessment, Development, and Evaluation. Our study was registered with PROSPERO, number CRD42017076104.

FINDINGS

We identified 43 243 potentially eligible records. 46 articles were narratively synthesised and 19 contributed to the meta-analysis. All studies were published in high-income countries and examined policies of entry (nine articles) and integration (37 articles). Restrictive entry policies (eg, temporary visa status, detention) were associated with poor mental health (SMD 0·44, 95% CI 0·13-0·75; I2=92·1%). In the integration phase, restrictive policies in general, and specifically regarding welfare eligibility and documentation requirements, were found to increase odds of poor self-rated health (OR 1·67, 95% CI 1·35-1·98; I2=82·0%) and mortality (1·38, 1·10-1·65; I2=98·9%). Restricted eligibility for welfare support decreased the odds of general health-care service use (0·92, 0·85-0·98; I2=0·0%), but did not reduce public health insurance coverage (0·89, 0·71-1·07; I2=99·4%), nor markedly affect proportions of people without health insurance (1·06, 0·90-1·21; I2=54·9%).

INTERPRETATION

Restrictive entry and integration policies are linked to poor migrant health outcomes in high-income countries. Efforts to improve the health of migrants would benefit from adopting a Health in All Policies perspective.

FUNDING

Swedish Council for Health, Working Life, and Social Research; UK Medical Research Council; Scottish Government Chief Scientist Office.

Applying measures of discriminatory accuracy to revisit traditional risk factors for being small for gestational age in Sweden: a national cross-sectional study

OBJECTIVES

Small for gestational age (SGA) is considered as an indicator of intrauterine growth restriction, and multiple maternal and newborn characteristics have been identified as risk factors for SGA. This knowledge is mainly based on measures of average association (ie, OR) that quantify differences in average risk between exposed and unexposed groups. Nevertheless, average associations do not assess the discriminatory accuracy of the risk factors (ie, its ability to discriminate the babies who will develop SGA from those that will not). Therefore, applying measures of discriminatory accuracy rather than measures of association only, our study revisits known risk factors of SGA and discusses their role from a public health perspective.

DESIGN

Cross-sectional study. We measured maternal (ie, smoking, hypertension, age, marital status, education) and delivery (ie, sex, gestational age, birth order) characteristics and performed logistic regression models to estimate both ORs and measures of discriminatory accuracy, like the area under the receiver operating characteristic curve (AU-ROC) and the net reclassification improvement.

SETTING

Data were obtained from the Swedish Medical Birth Registry.

PARTICIPANTS

Our sample included 731 989 babies born during 1987-1993.

RESULTS

We replicated the expected associations. For instance, smoking (OR=2.57), having had a previous SGA baby (OR=5.48) and hypertension (OR=4.02) were strongly associated with SGA. However, they show a very small discriminatory accuracy (AU-ROC≈0.5). The discriminatory accuracy increased, but remained unsatisfactorily low (AU-ROC=0.6), when including all variables studied in the same model.

CONCLUSIONS

Traditional risk factors for SGA alone or in combination have a low accuracy for discriminating babies with SGA from those without SGA. A proper understanding of these findings is of fundamental relevance to address future research and to design policymaking recommendations in a more informed way.

[Notes on vital statistics for the study of perinatal health]

Vital statistics, published by the National Statistics Institute in Spain, are a highly important source for the study of perinatal health nationwide. However, the process of data collection is not well-known and has implications both for the quality and interpretation of the epidemiological results derived from this source. The aim of this study was to present how the information is collected and some of the associated problems. This study is the result of an analysis of the methodological notes from the National Statistics Institute and first-hand information obtained from hospitals, the Central Civil Registry of Madrid, and the Madrid Institute for Statistics. Greater integration between these institutions is required to improve the quality of birth and stillbirth statistics.

The effect of Swedish snuff (snus) on offspring birthweight: a sibling analysis

Current observational evidence indicates that maternal smoking during pregnancy is associated with reduced birthweight in offspring. However, less is known about the effect of smokeless tobacco on birthweight and about the possible mechanisms involved in this relationship. This paper studies the effect of Swedish smokeless tobacco (snus) on offspring birthweight comparing the results obtained from a conventional linear regression analysis and from a quasi-experimental sibling design using a multilevel linear regression analysis. From the Swedish Medical Birth Register, we investigated 604,804 singletons born between 2002 and 2010. From them, we isolated 8,861 siblings from 4,104 mothers with discrepant snus-use habits (i.e., women who had at least one pregnancy during which they used snus and at least one other pregnancy in which they did not). The conventional analysis shows that continuous snus use throughout the pregnancy reduces birthweight in 47 g while quitting or relapsing snus has a minor and statistically non-significant effect (−6 g and −4 g, respectively). However, using a sibling analysis the effect observed for mothers who continue to use snus during pregnancy is less intense than that observed with previous conventional analyses (−20 g), and this effect is not statistically significant. Sibling analysis shows that quitting or relapsing snus use after the first trimester slightly reduces birthweight (14 g).However, this small change is not statistically significant. The sibling analysis provides strong causal evidence indicating that exposure to snus during pregnancy has a minor effect on birthweight reduction. Our findings provide a new piece of causal evidence concerning the effect of tobacco on birthweight and support the hypothesis that the harmful effect of smoking on birthweight is not mainly due to nicotine.