The effect of increased alcohol availability on alcohol-related health problems up to the age of 42 among children exposed in utero: a natural experiment

Relationships Between Alcohol Policies and Infant Morbidities and Injuries

INTRODUCTION

Previous research has found that policies specifically focused on pregnant people's alcohol use are largely ineffective. Therefore, the purpose of this study is to analyze the relationships between general population policies regulating alcohol physical availability and outcomes related to pregnant people's alcohol use, specifically infant morbidities and injuries.

METHODS

Outcome data were obtained from Merative MarketScan, a longitudinal commercial insurance claims data set. Policy data were obtained from the National Institute on Alcohol Abuse and Alcoholism's Alcohol Policy Information System, the National Alcohol Beverage Control Association, and Liquor Handbooks and merged using policies in effect during the estimated year of conception. Relationships between state-level policies regulating sites, days/hours, and government monopoly of liquor sales and infant morbidities and injuries were examined. Analyses used logistic regression with individual controls, fixed effects for state and year, state-specific time trends, and SEs clustered by state. The study analysis was conducted from 2021 to 2023.

RESULTS

The analytic sample included 1,432,979 infant-birthing person pairs, specifically people aged 25-50 years who gave birth to a singleton between 2006 and 2019. A total of 3.1% of infants had a morbidity and 2.1% of infants had an injury. State government monopoly on liquor sales was associated with reduced odds of infant morbidities and injuries, whereas gas station liquor sales were associated with increased odds of infant morbidities and injuries. Allowing liquor sales after 10PM was associated with increased odds for infant injuries. No effect was found for allowing liquor sales in grocery stores or on Sundays.

CONCLUSIONS

Findings suggest that limiting alcohol availability for the general population may help reduce adverse infant outcomes related to pregnant people's alcohol use.

The association of lowered alcohol prices with birth outcomes and abortions: A population-based natural experiment

BACKGROUND AND AIMS

Alcohol use during pregnancy remains an important risk factor for adverse birth outcomes, but little is known regarding how alcohol prices affect pregnancy outcomes on the population level. We assess the associations between decreased alcohol prices with birth outcomes and abortions.

DESIGN

Using national registers, we used interrupted time-series modelling to compare outcomes of pregnancies conceived before and after a tax cut, resulting in 33% mean decrease of off-premise alcohol prices on 1 March 2004. We also addressed possible heterogeneity of the associations by maternal age and household income.

SETTING

Finland.

PARTICIPANTS

All registered pregnancies starting 2 years before and 1 year after the alcohol price cut (analysis sample consisted of 169 735 live births and 32 441 abortions).

MEASUREMENTS

The outcomes were birth weight, gestational age, the probability of low birth weight (< 2500 g at birth), preterm birth (< 37 weeks of gestation), any congenital malformations and share of registered abortions of pregnancies.

FINDINGS

On the population level, lowered alcohol prices were associated with an increase in abortions immediately after the price cut [+0.84 percentage points; 95% confidence interval (CI) = 0.2, 1.4]. For birth outcomes, negative associations were observed among women in the lowest income quintile; for example, increased probabilities of low birth weight (+1.5 percentage points; 95% CI = 0.4, 2.6) and preterm birth (+1.98 percentage points; 95% CI = 0.8, 3.2). All changes were strongest immediately after the price cut and attenuated during the course of the following year.

CONCLUSIONS

Lowered alcohol prices in Finland were associated with a short-term increase in adverse birth outcomes among low-income mothers and an overall increase in abortions.

Applying Causal Inference Methods in Psychiatric Epidemiology: A Review

IMPORTANCE

Associations between putative risk factors and psychiatric and substance use disorders are widespread in the literature. Basing prevention efforts on such findings is hazardous. Applying causal inference methods, while challenging, is central to developing realistic and potentially actionable etiologic models for psychopathology.

OBSERVATIONS

Causal methods can be divided into randomized clinical trials (RCTs), natural experiments, and statistical models. The first 2 approaches can potentially control for both known and unknown confounders, while statistical methods control only for known and measured confounders. The criterion standard, RCTs, can have important limitations, especially regarding generalizability. Furthermore, for ethical reasons, many critical questions in psychiatric epidemiology cannot be addressed by RCTs. We review, with examples, methods that try to meet as-if randomization assumptions, use instrumental variables, or use pre-post designs, regression discontinuity designs, or co-relative designs. Each method has strengths and limitations, especially the plausibility of as-if randomization and generalizability. Of the large family of statistical methods for causal inference, we examine propensity scoring and marginal models, which are best applied to samples with strong predictors of risk factor exposure.

CONCLUSIONS AND RELEVANCE

Causal inference is important because it informs etiologic models and prevention efforts. The view that causation can be definitively resolved only with RCTs and that no other method can provide potentially useful inferences is simplistic. Rather, each method has varying strengths and limitations. We need to avoid the extremes of overzealous causal claims and the cynical view that potential causal information is unattainable when RCTs are infeasible. Triangulation, which applies different methods for elucidating causal inferences to address to the same question, may increase confidence in the resulting causal claims.