Burn Patients and Mental Health: A Matched Cohort Study.

OBJECTIVE: To determine the association between burns and hospitalization for mental health disorders up to three decades later. SUMMARY BACKGROUND DATA: Burns are associated with pain, disability, and scarring, but the long-term impact on mental health is unclear. METHODS: We analyzed a cohort of 23,726 burn patients aged ≥10 years who were matched to 223,626 controls from Quebec, Canada, between 1989 and 2022. The main exposure was admission for a burn. We followed patients during 3,642,206 person-years of follow-up to identify future hospitalizations for psychiatric disorders, substance use disorders, and suicide attempts. We estimated adjusted hazard ratios (HR) with 95% confidence intervals (CI) for the association between burns and subsequent mental health hospitalization using Cox proportional hazards regression. RESULTS: Burn patients had 1.76 times greater risk of mental health hospitalization over time (95% CI 1.72-1.81), compared with controls. Associations were present regardless of burn site, but were greatest for burns covering ≥50% of the body (HR 3.29, 95% CI 2.61-4.15), third degree burns (HR 2.04, 95% CI 1.94-2.14), and burns requiring skin grafts (HR 2.00, 95% CI 1.90-2.10). Compared with controls, burn patients had more than two times the risk of hospitalization for eating disorders (HR 3.14, 95% CI 2.50-3.95), psychoactive substance use disorders (HR 2.27, 95% CI 2.17-2.39), and suicide attempts (HR 2.42, 95% CI 2.23-2.62). Risks were particularly elevated within 5 years of the burn, but persisted throughout follow-up. CONCLUSIONS: Burns are associated with an increased risk of hospitalization for mental health disorders up to 30 years later.

Association of maternal cancer with congenital anomalies in offspring.

BACKGROUND: Congenital anomalies are common, but the possibility that maternal cancer increases the chance of having a child with a birth defect is not fully understood. OBJECTIVES: To examine the association between maternal cancer before or during pregnancy and the risk of birth defects in offspring. METHODS: We conducted a retrospective cohort study of live births in Quebec, Canada, between 1989 and 2022 using hospital data. The main exposure measure was maternal cancer before or during pregnancy. The outcome included birth defects detected in offspring during gestation or at birth. We estimated risk ratios (RR) and 95% confidence intervals (CI) for the association of maternal cancer with birth defects using log-binomial regression models adjusted for potential confounders. RESULTS: In this study of 2,568,120 newborns, birth defects were present in 6.0% and 6.7% of infants whose mothers had cancer before or during pregnancy, respectively, compared with 5.7% of infants whose mothers never had cancer. Cancer during pregnancy was associated with heart (RR 1.58, 95% CI 1.03, 2.44), nervous system (RR 4.05, 95% CI 2.20, 7.46) and urinary defects (RR 1.72, 95% CI 1.01, 2.95). Among specific types of malignancies during pregnancy, breast cancer was the most prominent risk factor for birth defects (RR 1.55, 95% CI 1.02, 2.37). Cancer before pregnancy was not associated with any type of birth defect or with defects overall (RR 1.01, 95% CI 0.92, 1.11). Moreover, no specific type of cancer before pregnancy was associated with an increased risk of birth defects. CONCLUSIONS: Maternal cancer during pregnancy is associated with the risk of congenital anomalies in offspring, however, cancer before pregnancy is not associated with this outcome.

Preterm birth and risk of hospitalisation for complex chronic conditions during childhood and adolescence.

AIM: To examine the relationship between preterm birth and hospitalisation for paediatric complex chronic conditions. METHODS: We conducted a cohort study of 1 269 745 children born between 2006 and 2022 in Quebec, Canada. We classified preterm birth as extreme (<28 weeks), very (28-31 weeks), and moderate (32-36 weeks). The outcome was hospitalisation for complex chronic conditions, including neurologic, neuromuscular, cardiovascular, respiratory, renal, gastrointestinal, haematologic, immunologic, endocrine, and neoplastic disorders up to 16 years of age. We computed adjusted hazard ratios (HR) and 95% confidence intervals (CI) for the association between preterm birth and complex chronic conditions during 9 948 734 person-years of follow-up. RESULTS: Hospitalisation rates for complex chronic conditions were higher for children born preterm than at term (6.88 vs. 2.24 per 1000 person-years). Preterm birth was associated with all complex chronic conditions, especially respiratory (HR 4.64, 95% CI 4.01-5.37), cardiovascular (HR 3.68, 95% CI 3.47-3.90), and neurologic disorders (HR 3.48, 95% CI 3.21-3.77). Associations were present at all ages and for all degrees of prematurity, but were strongest with extreme prematurity. CONCLUSION: Preterm birth increases the risk of hospitalisation for complex chronic conditions up to age 16 years. Preterm children may benefit from enhanced care throughout childhood and adolescence.

Validation of Database Autopsy for Review of Pregnancy-Associated Deaths in Canada.

The database autopsy method was developed to determine probable causes of maternal deaths in the Canadian Institute for Health Information's hospital discharge abstract database; however, the method has yet to be validated. Using immediate cause of death information from Québec's hospitalization database as the gold standard, this study assessed the validity and reliability of the database autopsy method for pregnancy-associated deaths. The method had high sensitivity and specificity for identifying the most common causes of these deaths, as well as high interobserver agreement. We conclude that the database autopsy method is valid and reliable overall.

Connection between maternal suicide attempt and chronic morbidity in children.

BACKGROUND: Maternal suicide attempts are associated with adverse psychosocial outcomes in children, but the association with chronic morbidity is poorly understood. We examined the relationship between maternal suicide attempt and risk of hospitalization for potentially preventable conditions in offspring. METHODS: We analyzed a longitudinal cohort of 1 032 210 children born in Quebec, Canada between 2006 and 2019. The main exposure measure was maternal suicide attempt before or during pregnancy. Outcomes included child hospitalizations for potentially preventable conditions, including infectious diseases, dental caries, atopy, and injury up to 14 years after birth. We used adjusted Cox proportional hazards regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of maternal suicide attempt with risk of hospitalization for these outcomes. RESULTS: Compared with no suicide attempt, children whose mothers attempted suicide had an increased risk of hospitalization for infectious diseases (HR 1.11, 95% CI 1.06-1.16), dental caries (HR 1.31, 95% CI 1.15-1.48), and injury (HR 1.16, 95% CI 1.03-1.31). Risk of hospitalization for any of these outcomes was greater if mothers attempted suicide by hanging (HR 1.46, 95% CI 1.22-1.75), had their first attempt between the age of 25 and 34 years (HR 1.27, 95% CI 1.13-1.42), and had 3 or more attempts (HR 1.56, 95% CI 1.27-1.91). Maternal suicide attempts were more strongly associated with child hospitalization before 10 years of age. CONCLUSIONS: Children whose mothers have a history of suicide attempt have an elevated risk of hospitalization for potentially preventable conditions.

Second-trimester abortion and risk of live birth.

BACKGROUND: Second-trimester abortion may result in a live birth, but the extent to which this outcome occurs is unknown. OBJECTIVE: This study aimed to examine rates of live birth after pregnancy termination in the second trimester and identify associated risk factors. STUDY DESIGN: We conducted a retrospective cohort study of 13,777 second-trimester abortions occurring in hospital settings between April 1, 1989 and March 31, 2021 in Quebec, Canada. The exposure was induced abortion between 15 and 29 weeks of gestation, including the indication for (fetal anomaly, maternal emergency, other) and use of feticidal injection (intracardiac/intrathoracic or intraamniotic). The primary outcome was live birth following abortion. We measured the rate of live birth per 100 abortions and used adjusted log-binomial regression models to estimate risk ratios and 95% confidence intervals for the association of fetal and maternal characteristics with the risk of live birth. We assessed the extent to which feticidal injection reduced the risk. RESULTS: Among 13,777 abortions between 15 and 29 weeks of gestation, 1541 (11.2%) led to live birth. Fetal anomaly was a common indication for termination (48.1%), and most abortions were by labor induction (72.2%). Compared with abortion between 15 and 19 weeks, abortion between 20 and 24 weeks was associated with 4.80 times the risk of live birth (95% confidence interval, 4.20-5.48), whereas abortion between 25 and 29 weeks was associated with 1.34 times the risk (95% confidence interval, 1.00-1.79). Feticidal injection reduced the risk of live birth by 57% compared with no injection (risk ratio, 0.43; 95% confidence interval, 0.36-0.51). Intracardiac or intrathoracic injection was particularly effective at preventing live birth (risk ratio, 0.02; 95% confidence interval, 0.01-0.07). CONCLUSION: Second-trimester abortion carries a risk of live birth, especially at 20 to 24 weeks of gestation, although feticidal injection may protect against this outcome.

Risk of recurrent severe maternal morbidity: a population-based study.

BACKGROUND: Severe maternal morbidity is a composite indicator of maternal health and obstetrical care. Little is known about the risk of recurrent severe maternal morbidity in a subsequent delivery. OBJECTIVE: This study aimed to estimate the risk of recurrent severe maternal morbidity in the next delivery after a complicated first delivery. STUDY DESIGN: We analyzed a population-based cohort study of women with at least 2 singleton hospital deliveries between 1989 and 2021 in Quebec, Canada. The exposure was severe maternal morbidity in the first hospital-recorded delivery. The study outcome was severe maternal morbidity at the second delivery. Log-binomial regression models adjusted for maternal and pregnancy characteristics were used to generate relative risks and 95% confidence intervals comparing women with and without severe maternal morbidity at first delivery. RESULTS: Among 819,375 women, 43,501 (3.2%) experienced severe maternal morbidity in the first delivery. The rate of severe maternal morbidity recurrence at second delivery was 65.2 vs 20.3 per 1000 in women with and without previous severe maternal morbidity (adjusted relative risk, 3.11; 95% confidence interval, 2.96-3.27). The adjusted relative risk for recurrence of severe maternal morbidity was greatest among women who had ≥3 different types of severe maternal morbidity at their first delivery, relative to those with none (adjusted relative risk, 5.50; 95% confidence interval, 4.26-7.10). Women with cardiac complication at first delivery had the highest risk of severe maternal morbidity in the next delivery. CONCLUSION: Women who experience severe maternal morbidity have a relatively high risk of recurrent morbidity in the subsequent pregnancy. In women with severe maternal morbidity, these study findings have implications for prepregnancy counseling and maternity care in the next pregnancy.

Shifting age of child eating disorder hospitalizations during the Covid-19 pandemic.

BACKGROUND: We studied the effect of the Covid-19 pandemic on child eating disorder hospitalizations in Quebec, Canada. Quebec had one of the strictest lockdown measures targeting young people in North America. METHODS: We analyzed eating disorder hospitalizations in children aged 10-19 years before and during the pandemic. We used interrupted time series regression to assess trends in the monthly number of hospitalizations for anorexia nervosa, bulimia nervosa, and other eating disorders before the pandemic (April 2006 to February 2020), and during the first (March to August 2020) and second waves (September 2020 to March 2021). We determined the types of eating disorders requiring hospital treatment and identified the age, sex and socioeconomic subgroups that were most affected. RESULTS: Hospitalization rates for eating disorders increased during the first (6.5 per 10,000) and second waves (12.8 per 10,000) compared with the period before the pandemic (5.8 per 10,000). The increase occurred for anorexia nervosa as well as other types of eating disorders. The number of girls and boys aged 10-14 years admitted for eating disorders increased during wave 1. Wave 2 triggered an increase in eating disorder admissions among girls aged 15-19 years. Hospitalization rates increased earlier for advantaged than disadvantaged youth. CONCLUSIONS: The Covid-19 pandemic affected hospitalizations for anorexia nervosa as well as other eating disorders, beginning with girls aged 10-14 years during wave 1, followed by girls aged 15-19 years during wave 2. Boys aged 10-14 years were also affected, as well as both advantaged and disadvantaged youth.

Association of hospitalization for suicide attempts in adolescent girls with subsequent hospitalization for eating disorders.

OBJECTIVE: To determine the association between adolescent hospitalization for suicide attempts and the subsequent risk of eating disorder hospitalization. METHOD: This was a cohort study of 162,398 adolescent girls in Quebec, Canada, including 7741 with suicide attempts before 20 years of age, matched to 154,657 adolescents with no attempt between 1989 and 2019. The main exposure measure was suicide attempt hospitalization. The main outcome measure was hospitalization for an eating disorder up to 31 years later, including anorexia nervosa, bulimia nervosa, and other eating disorders. We used adjusted Cox regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between adolescent suicide attempts and eating disorder hospitalization. RESULTS: Adolescent girls admitted for a suicide attempt had 5.55 times the risk of eating disorder hospitalization over time (95% CI 3.74-8.23), compared with matched controls. Suicide attempt was associated with anorexia nervosa (HR 3.57, 95% CI 1.78-7.17) and bulimia nervosa and other eating disorders (HR 8.55, 95% CI 5.48-13.32). Associations were pronounced in girls with repeated suicide attempts. Girls who attempted suicide through self-poisoning had an elevated risk of anorexia nervosa, whereas girls who used violent methods such as cutting or piercing had a greater risk of bulimia nervosa and other eating disorders. Suicide attempt was strongly associated with eating disorder hospitalization in the year following the attempt, but associations persisted throughout follow-up. DISCUSSION: Suicide attempt admission is associated with the long-term risk of eating disorder hospitalization in adolescent girls. PUBLIC SIGNIFICANCE: This study of adolescent girls suggests that suicide attempt admission is associated with the long-term risk of hospitalization for eating disorders. The risk is greatest in the year after the attempt, but persists over time. Adolescents who present with a suicide attempt may benefit from screening for eating disorders and long-term follow-up to help prevent the exacerbation or development of eating disorders.

Severe neonatal birth injury: Observational study of associations with operative, cesarean, and spontaneous vaginal delivery.

AIM: To determine the association of successful and unsuccessful operative vaginal delivery attempts with risk of severe neonatal birth injury. METHODS: We conducted a population-based observational study of 1 080 503 births between 2006 and 2019 in Quebec, Canada. The main exposure was operative vaginal delivery with forceps or vacuum, elective or emergency cesarean with or without an operative vaginal attempt, and spontaneous delivery. The outcome was severe birth injury, including intracranial hemorrhage, brain and spinal damage, Erb's paralysis and other brachial plexus injuries, epicranial subaponeurotic hemorrhage, skull and long bone fractures, and liver, spleen, and other neonatal body injuries. We determined the association of delivery mode with risk of severe birth injury using adjusted risk ratios (RR) and 95% confidence intervals (CI). RESULTS: A total of 8194 infants (0.8%) had severe birth injuries. Compared with spontaneous delivery, vacuum (RR 2.98, 95% CI 2.80-3.16) and forceps (RR 3.35, 95% CI 3.07-3.66) were both associated with risk of severe injury. Forceps was associated with intracranial hemorrhage (RR 16.4, 95% CI 10.1-26.6) and brain and spinal damage (RR 13.5, 95% CI 5.72-32.0), while vacuum was associated with epicranial subaponeurotic hemorrhage (RR 27.5, 95% CI 20.8-36.4) and skull fractures (RR 2.04, 95% CI 1.86-2.25). Emergency cesarean after an unsuccessful operative attempt was associated with intracranial and epicranial subaponeurotic hemorrhage, but elective and other emergency cesareans were not associated with severe injury. CONCLUSIONS: Operative vaginal delivery and unsuccessful operative attempts that result in an emergency cesarean are associated with elevated risks of severe birth injury.

Longitudinal risk of maternal hospitalization for mental illness following preterm birth.

BACKGROUND: Preterm birth may affect maternal mental health, yet most studies focus on postpartum mental disorders only. We explored the relationship between preterm delivery and the long-term risk of maternal hospitalization for mental illness after pregnancy. METHODS: We performed a longitudinal cohort study of 1,381,300 women who delivered between 1989 and 2021 in Quebec, Canada, and had no prior history of mental illness. The exposure was preterm birth, including extreme (<28 weeks), very (28-31 weeks), and moderate to late (32-36 weeks). The outcome was subsequent maternal hospitalization for depression, bipolar, psychotic, stress and anxiety, personality disorders, and self-harm up to 32 years later. We used adjusted Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between preterm birth and mental illness hospitalization. RESULTS: Compared with term, women who delivered preterm had a higher rate of mental illness hospitalization (3.81 vs. 3.01 per 1000 person-years). Preterm birth was associated with any mental illness (HR 1.38, 95% CI 1.35-1.41), including depression (HR 1.37, 95% CI 1.32-1.41), psychotic disorders (HR 1.35, 95% CI 1.25-1.44), and stress and anxiety disorders (HR 1.42, 95% CI 1.38-1.46). Delivery at any preterm gestational age was associated with the risk of mental hospitalization, but risks were greatest around 34 weeks of gestation. Preterm birth was strongly associated with mental illness hospitalization within 2 years of pregnancy, although associations persisted throughout follow-up. CONCLUSIONS: Women who deliver preterm may be at risk of mental disorders in the short and long term.

Prenatal cannabis use disorder and future risk of road traffic injuries in Canadian children.

The extent to which child traffic injuries may be attributed to parents who use cannabis before driving is unknown. We investigated whether prenatal cannabis use disorders may predict future road traffic injuries in children. We conducted a cohort study of 792,082 children in Quebec, Canada with 6,280,663 years of follow-up between 2006 and 2019. The main exposure measure was maternal cannabis use disorder before or during pregnancy. The main outcome measure was future hospitalizations for transport-related injuries in children after birth. Using Cox proportional hazards regression models adjusted for potential confounders, we estimated hazard ratios and 95% confidence intervals (CI) for the association of prenatal cannabis use disorders with transport-related injuries in children. Maternal cannabis use disorders before birth were associated with 5.64 times the risk of hospitalization for future motor vehicle crash injuries in children (95% CI 2.61-12.21). The risk increased with the child's age. Prenatal cocaine, opioid, and other drug use disorders were not associated with pediatric transport-related injuries. Maternal cannabis use disorders before birth may be an early predictor of childhood injuries from motor vehicle crashes.

Tombstone size and life expectancy: a cross-sectional analysis of cemetery data before the turn of the century.

The extent to which socioeconomic status was associated with life expectancy in the 19th and early part of the twentieth century is poorly understood. We sought to determine the association between a deceased individual's tombstone size, a potential marker of socioeconomic status, and their age of death in the late modern period. We conducted a cross-sectional study of 276 deceased individuals buried between 1820 and 1992 in a large cemetery in Quebec, Canada. The main outcome measure was age of death. We used generalized linear models adjusted for sex, marital status, and year of death to determine whether tombstone height and volume were associated with a greater number of years lived. Tombstone height and volume were associated with an older age of death in adjusted regression models. Individuals with tall tombstones lived 9.6 years longer than those with short tombstones (95% confidence interval, CI 3.9 to 15.4). Individuals with large volume tombstones lived 6.2 years longer than those with small tombstones (95% CI 1.7 to 10.8). Our findings indicate that in the 1800s and early 1900s, tombstone size was strongly associated with age of death. A possible explanation for this occurrence is that wealthy individuals, capable of purchasing more sizeable tombstones, were more likely to live a longer and healthier life.

Maternal Substance Abuse and the Later Risk of Fractures in Offspring: L'abus maternel de substances et le risque ultérieur de fractures chez les enfants.

OBJECTIVE: To assess the association of maternal illicit drug abuse before or during pregnancy with future fractures in offspring. METHODS: We performed a longitudinal cohort study of 792,022 infants born in hospitals of Quebec, Canada, between 2006 and 2016, with 5,457,634 person-years of follow-up. The main exposure was maternal substance abuse before or during pregnancy, including cocaine, opioid, cannabis, and other illicit drugs. The main outcome measure was hospitalization for traumatic fracture in offspring up to 12 years of age. We used adjusted Cox regression models to compute hazard ratios (HR) and 95% confidence intervals (CI) for the association of maternal drug abuse with the subsequent risk of fracture in children. RESULTS: The incidence of child fractures was higher for maternal illicit drug abuse than no drug abuse (21.2 vs. 15.4 per 10,000 person-years). Maternal drug abuse before or during pregnancy was associated with 2.35 times the risk of assault-related fractures (95% CI, 1.29 to 4.27) and 2.21 times the risk of transport accident-related fractures (95% CI, 1.34 to 3.66), compared with no drug abuse. Associations were strongest before 6 months of age for assault-related fractures (HR = 2.14; 95% CI, 0.97 to 4.72) and after 6 years for transport-related fractures (HR = 2.86; 95% CI, 1.35 to 6.05). Compared with no drug abuse, associations with assault and transport-related fractures were elevated for all drugs including cocaine, opioids, and cannabis. CONCLUSIONS: Maternal illicit drug abuse is associated with future child fractures due to assault and transport accidents.

Preeclampsia and the longitudinal risk of hospitalization for depression at 28 years.

PURPOSE: The association between pregnancy characteristics and risk of depression in women is poorly understood. We investigated the relationship between preeclampsia and risk of hospitalization for depression over three decades. METHODS: We carried out a longitudinal cohort study of 1,210,963 women who delivered an infant in any hospital in Quebec, Canada, between 1989 and 2016. The exposure was preeclampsia at the first or in subsequent pregnancies, including preeclampsia onset time (early < 34 weeks vs. late ≥ 34 weeks of gestation) and severity (mild, severe, superimposed). The outcome was hospitalization for depression any time after pregnancy. We used Cox proportional hazards regression models adjusted for maternal characteristics to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of preeclampsia with depression hospitalization. RESULTS: Women with preeclampsia had a higher incidence of hospitalization for depression compared with no preeclampsia (1.43 vs. 1.14 per 1000 person-years). Preeclampsia was associated with 1.16 times the risk of depression hospitalization after 28 years of follow-up (95% CI 1.09-1.23). Associations were present for mild (HR 1.15, 95% CI 1.07-1.24), severe (HR 1.16, 95% CI 1.04-1.29) and late onset preeclampsia (HR 1.17, 95% CI 1.10-1.25). Risks were more pronounced after the first year postpartum. CONCLUSION: Preeclampsia appears to be associated with the risk of depression hospitalization several decades after pregnancy. Clinicians who care for women with mental health disorders should be aware that a history of preeclampsia increases the risk of severe depression.

Necrotizing Fasciitis: Association with Pregnancy-related Risk Factors Early in Life.

Background: Pregnancy-related risk factors for necrotizing fasciitis are poorly understood. We investigated pregnancy-related characteristics associated with the long-term risk of developing necrotizing fasciitis, a rare life-threatening infectious disease. Methods: We analyzed a longitudinal cohort of 1,344,996 parous women in Quebec, Canada between 1989 and 2020. The main exposure measures included complications of pregnancy such as gestational diabetes, preterm delivery, metabolic disorder, and other maternal characteristics. We followed the women over time to identify future hospitalizations for necrotizing fasciitis up to three decades after delivery. We estimated adjusted hazard ratios (HR) and 95% confidence intervals (CI) for the association of pregnancy characteristics with risk of necrotizing fasciitis in time-varying Cox proportional hazards regression models. Results: A total of 420 women were hospitalized for necrotizing fasciitis during follow-up, including 83 (19.8%) with diabetes-related necrotizing fasciitis. The incidence of necrotizing fasciitis was elevated for women with gestational diabetes (2.9 per 100,000 person-years), preterm delivery (3.2 per 100,000 person-years), and metabolic disorders (5.4 per 100,000 person-years), compared with no pregnancy complication (1.1 per 100,000 person-years). Compared with no pregnancy complication, gestational diabetes was associated with 1.87 times the risk (95% CI 1.38-2.53), preterm delivery with 2.10 times the risk (95% CI 1.65-2.66), and metabolic disorder with 3.72 times the risk (95% CI 2.92-4.74) of developing necrotizing fasciitis over time. Pregnancy complications were more strongly associated with the risk of necrotizing fasciitis 5 years or more after delivery. Conclusions: Complications of pregnancy may be associated with the long-term risk of necrotizing fasciitis in women.

Cannabis use disorder and the future risk of cardiovascular disease in parous women: a longitudinal cohort study.

BACKGROUND: Cannabis use is increasing in women of reproductive age, but whether cannabis use disorders increase the long-term risk of cardiovascular disease in this population is not known. Cannabis may cause tachycardia, hypertension, cerebral vasoconstriction, and other adverse cardiovascular effects and has been associated with acute myocardial infarction and stroke. Data on the long-term effects of cannabis on the cardiovascular system are more limited. We assessed the relationship between cannabis use disorders early in life and the future risk of cardiovascular disease in women. METHODS: We analyzed a longitudinal cohort of 1,247,035 pregnant women in Quebec, Canada, between 1989 and 2019. The main exposure was current or past history of cannabis use disorders at cohort entry. The main outcome measure included future hospital admission for any cardiovascular disorder during 18,998,986 person years of follow-up. We used Cox proportional hazards regression models adjusted for patient characteristics to compute hazard ratios (HR) and 95% confidence intervals (CI) for the association of cannabis use disorder with the later risk of cardiovascular hospitalization. RESULTS: Women with cannabis use disorders had a higher incidence of cardiovascular hospitalization than unexposed women (58.4 vs. 33.6 per 10,000 person years). Cannabis use disorder was associated with 1.48 times the risk of cardiovascular hospitalization (95% CI 1.27-1.72), compared with no cannabis use disorder. The association was greater for cannabis with concomitant use of other substances (HR 1.84, 95% CI 1.53-2.21) than for cannabis alone (HR 1.30, 95% CI 0.99-1.72). Cannabis use disorder was strongly associated with hemorrhagic stroke, even with adjustment for other substance use (HR 2.08, CI 1.07-4.05). CONCLUSIONS: Cannabis use disorders may increase the long-term risk of cardiovascular disease in women, particularly hemorrhagic stroke. However, some of the excess risk may be due to concomitant use of other substances.

Preterm birth and the future risk of orthopedic fracture.

BACKGROUND: Preterm birth occurs during a critical period of bone mineralization. We assessed whether preterm birth increases the risk of childhood fracture. METHODS: We analyzed a cohort of 788,903 infants born between 2006 and 2016 in Quebec, Canada. The exposure was preterm birth (<37 weeks). The outcome was any future hospitalization for fracture before 2018. We estimated hazard ratios (HR) and 95% confidence intervals (CI) for the association of prematurity with fractures in adjusted Cox regression models. We determined if the risk of facture varied by the child's age. RESULTS: The incidence of fracture hospitalizations was higher in preterm children than in term children (17.9 vs. 15.3 per 10,000 person-years). Compared with term, preterm children had 1.27 times the risk of femur fracture hospitalization (95% CI 1.01-1.60) and 2.27 times the risk of assault-related fractures (95% CI 1.37-3.76). Preterm children had 2.20 times the risk of femur fracture between 6 and 17 months of age (95% CI 1.45-3.35). CONCLUSIONS: Preterm birth is associated with an increased risk of hospitalization for femur fractures and assault-related fractures. Associations are stronger before 18 months of age. Families of preterm children may benefit from counseling and support for fracture prevention during early childhood.

Neonatal phototherapy and future risk of childhood cancer.

We sought to determine if neonatal phototherapy is associated with a greater risk of childhood cancer. We conducted a retrospective cohort study of 786,998 infants born in hospitals of Quebec, Canada between 2006 and 2016, with 4,660,868 person-years of follow-up over an 11-year period. The exposures were neonatal phototherapy (32,314 or 4.1% of infants) and untreated jaundice (91,855 or 11.7% of infants). The outcome was hospitalization for solid or hematopoietic childhood tumours between 2 months and 11 years of age. We used Cox proportional hazards regression models to compute hazard ratios (HR) and 95% confidence intervals (CI) for the association of phototherapy with childhood cancer, adjusted for infant characteristics. The incidence of childhood cancer was higher for infants with phototherapy (25.1 per 100,000 person-years) and untreated jaundice (23.0 per 100,000) compared to unexposed infants (21.6 per 100,000). Phototherapy appeared to be associated with late onset solid tumours, including brain/central nervous system cancers. Between age 4 and 11 years, children who received neonatal phototherapy had more than 2 times the risk of any solid tumour compared to unexposed children (HR 2.26, 95% CI 1.34-3.81). Results were similar for phototherapy compared against untreated jaundice. A similar trend was however less apparent for hematopoietic cancer. We conclude that neonatal phototherapy may be associated with a slightly increased risk of solid tumours in childhood, but cannot rule out an effect of bilirubin. Minimizing unnecessary exposure to phototherapy through adherence to recommended thresholds for treatment is encouraged.

Maternal prepregnancy surgery and risk of neonatal abstinence syndrome in future newborns: a longitudinal cohort study.

BACKGROUND: Neonatal abstinence syndrome is increasingly prevalent, and may be related to opioid use disorders caused by postoperative prescriptions for pain control. We assessed the association of maternal prepregnancy surgery with risk of neonatal abstinence syndrome from opioid use disorders in future pregnancies. METHODS: We conducted a longitudinal retrospective cohort study of 2 182 365 deliveries in Quebec, Canada, between 1989 and 2016. The main exposure was maternal prepregnancy surgery. The main outcome measure was neonatal abstinence syndrome in offspring. We adjusted associations for maternal comorbidity and pregnancy characteristics using log-binomial regression models. RESULTS: The prevalence of neonatal abstinence syndrome in the cohort was 10.7 per 10 000 births. Compared with no surgery, prepregnancy surgery was associated with a risk ratio (RR) of neonatal abstinence syndrome of 1.63 (95% confidence interval [CI] 1.49-1.78). Risk was greater for 3 or more prepregnancy surgeries (RR 2.34, 95% CI 2.07-2.63) and age < 15 years at first surgery (1 surgery: RR 2.08, 95% CI 1.71-2.54; 2 or more surgeries: RR 2.79, 95% CI 2.32-3.37). Nearly all surgical specialties increased the risk of neonatal abstinence syndrome, but associations were strongest for cardiothoracic surgery (RR 4.45, 95% CI 2.87-6.91), neurosurgery (RR 3.00, 95% CI 1.56-5.77) and urologic surgery (RR 3.03, 95% CI 2.16-4.26). INTERPRETATION: Prepregnancy surgery is associated with the risk of neonatal abstinence syndrome in future pregnancies. Prescription opioids for postsurgical pain may result in opioid use disorders during future pregnancies, inadvertently increasing the risk of neonatal abstinence syndrome in offspring.