Decomposing Socioeconomic Inequality Determinants in Suicide Deaths in Iran: A Concentration Index Approach

Background

It is recognized that socioeconomic status (SES) has a significant impact on health and wellbeing; however, the effect of SES on suicide is contested. This study explored the effect of SES in suicide deaths and decomposed inequality into its determinants to calculate relative contributions.

Methods

Through a cross-sectional study, 546 suicide deaths and 6,818 suicide attempts from January 1, 2010 to December 31, 2014 in Ilam Province, Western Iran were explored. Inequality was measured by the absolute concentration index (ACI) and decomposed contributions were identified. All analyses were performed using STATA ver. 11.2 (Stata Corp., College Station, TX, USA).

Results

The overall ACI for suicide deaths was -0.352 (95% confidence interval, -0.389 to -0.301). According to the results, 9.8% of socioeconomic inequality in suicide deaths was due to addiction in attempters. ACI ranged from -0.34 to -0.03 in 2010–2014, showing that inequality in suicide deaths declined over time.

Conclusion

Findings showed suicide deaths were distributed among the study population unequally, and our results confirmed a gap between advantaged and disadvantaged attempters in terms of death. Socioeconomic inequalities in suicide deaths tended to diminish over time, as suicide attempts progressed in Ilam Province.

Asthma in children in relation to pre-term birth and fetal growth restriction

To assess the impact of parental asthma on risk of pre-term birth (PTB) and intrauterine growth restriction, and their subsequent association with childhood asthma. Three sequential cross-sectional surveys were conducted in 1993 (3,746), 1998 (1,964) and 2006 (1,074) in the same 15 schools among 5-11 year old children in Merseyside using the same respiratory health questionnaire completed by parents (sample size in brackets). Between 1993 and 2006, prevalence of PTB varied between 12.4 and 15.2 %, and of small for gestational age (SGA or growth restricted) babies between 2.1 and 4.6 %, and maternal asthma prevalence between 8.1 and 13.4 %. For the combined surveys mothers with asthma were more likely to have a PTB than non-asthmatic mothers (OR 1.39, 95 % CI 1.10-1.95, p < 0.001), and in the 2006 survey were more likely to have an SGA baby. 40.9 % of PTBs of asthmatic mothers developed doctor diagnosed asthma compared to 34.3 % for term babies (adjusted OR 1.65, 1.34-2.04, p < 0.001). The corresponding estimates for the symptom triad of cough, wheeze and breathlessness were 19.4 and 17.6 % (adjusted OR 1.78, 0.79-3.98). Conversely SGA babies were less likely to develop doctor diagnosed asthma (adjusted OR 0.49, 0.27-0.90, p < 0.021), or the symptom triad of cough, wheeze and breathlessness (adjusted OR 0.22, 0.05-0.97, p < 0.043), whether or not the mother was asthmatic. Maternal asthma is an independent risk factor for PTB which predisposes to childhood asthma. Intrauterine growth restriction was protective against childhood asthma.

Interaction between maternal passive smoking during pregnancy and CYP1A1 and GSTs polymorphisms on spontaneous preterm delivery

OBJECTIVE

The present study aimed to examine the association between maternal passive smoking during pregnancy and the risk of spontaneous PTD and to explore the potential interaction of the single or joint gene polymorphism of CYP1A1 and GSTs with maternal passive smoking on the risk of spontaneous PTD.

METHOD

We investigated whether the association between maternal passive smoking and PTD can be modified by 2 metabolic genes, i.e. cytochrome P4501A1 (CYP1A1) and glutathione S-transferases (GSTs), in a case-control study with 198 spontaneous preterm and 524 term deliveries in Shenzhen and Foshan, China. We used logistic regression to test gene-passive smoking interaction, adjusting for maternal socio-demographics and prepregnancy body mass index.

RESULTS

Overall, maternal passive smoking during pregnancy was associated with higher risk of PTD (adjusted odds ratio = 2.20 [95% confidence interval: 1.56-3.12]). This association was modified by CYP1A1 and GSTs together, but not by any single genotype. For cross-categories of CYP1A1 Msp I and GSTs, maternal passive smoking was associated with higher risk of PTD among those women with CYP1A1 "TC/CC"+ GSTs "null", but not among women with other genotypes; and this interaction was significant (OR = 2.66 [95% CI: 1.19-5.97]; P-value: 0.017). For cross-categories of CYP1A1 BsrD I and GSTs, maternal passive smoking was associated with higher risk of PTD only among those women with CYP1A1"AG/GG"+ GSTs "null", but not among women with other genotypes; and this interaction was significant (OR = 3.00 [95% CI: 1.17-7.74]; P-value: 0.023).

CONCLUSIONS

Our findings suggest that the combined genotypes of CYP1A1 and GSTs can help to identify vulnerable pregnant women who are subject to high risk of spontaneous PTD due to passive smoking.

Prenatal smoking exposure and asymmetric fetal growth restriction

BACKGROUND

Prenatal smoking exposure causes intrauterine fetal growth restriction (IUGR), although its effects on fetal proportionality are less clearly defined.

AIM

The present study assessed fetal proportionality in babies with IUGR using maternal salivary cotinine to indicate maternal smoking exposure.

SUBJECTS AND METHODS

A case-control study at the Liverpool Women's Hospital, UK of babies with asymmetric and symmetric IUGR and non-growth restricted babies was carried out.

RESULTS

270 white women including 90 IUGR cases and 180 controls were enrolled. Asymmetry presented in 52.2% of IUGR cases. Geometric mean maternal cotinine concentration was higher with asymmetric (p=0.002) than symmetric IUGR (p=0.07), when compared to controls. Maternal smoking exposure was independently associated with asymmetric IUGR (OR 2.4, 95% CI, 1.5-4.4, p</=0.001). Maternal anaemia was more frequent in babies with symmetric IUGR (OR 1.9, 1.3-3.4, p=0.002), but not in asymmetric babies. Rohrer's index ranged between 1.64 and 2.25 for asymmetric infants and significantly decreased with increasing maternal cotinine concentration in IUGR babies. Increased cotinine was not associated with shortened gestational age in IUGR babies.

CONCLUSIONS

Asymmetric IUGR occurred more frequently in heavy smokers. Stopping smoking even late in pregnancy may be beneficial for improved fetal outcomes. Symmetric IUGR was associated with maternal anaemia, highlighting the importance of prenatal nutritional status.

Pregnancy late in life: a hospital-based study of birth outcomes

BACKGROUND

Pregnancy in older women is of great relevance, particularly in developed countries where many women experience pregnancy late in the childbearing age.

METHODS

A hospital-based data analysis of 9506 delivery records from 1998 to 2003 at the Liverpool Women's Hospital was undertaken to assess pregnancy outcomes in older women of reproductive age.

RESULTS

Overall, 2.4 % of mothers were >40 years of age (advanced), 5.6% were <20 years (adolescents), and 92% were between 20 and 40 years. The prevalence of low birthweight (LBW), preterm birth, and small for gestational age by maternal age category followed a U-shaped curve with nadirs in the middle age classes. The gestational age of older mothers was 1 week shorter than that for women aged 26-30 years (p = 0.005). Primiparaes >40 years were at higher risk for delivering a LBW (9.4% vs. 5.3%, p = 0.005) or a very preterm baby (8.9% vs. 4.4%, p = 0.001) than were multiparous mothers of the same age. There was an association between maternal advanced age and LBW (adjusted OR [AOR], 1.7, 95% CI 1.4-2.5, p = 0.001), preterm birth (AOR 1.4, 95% CI 1.1-2.4, p = 0.04), or very preterm birth (AOR 1.6, 95% CI 1.2-3.5, p = 0.002) after controlling for prenatal alcohol and smoking exposure, household deprivation, maternal anemia, obesity, parity, and single parenthood.

CONCLUSIONS

Pregnancy in older women is associated with adverse birth outcomes, particularly in primigravidas. Increased health promotion is required to highlight the risk of adverse birth outcomes in women who become pregnant for the first time in the late childbearing years.

Prenatal alcohol exposure, CYP17 gene polymorphisms and fetal growth restriction

OBJECTIVE

To determine the association of maternal CYP17 gene polymorphisms and prenatal alcohol consumption with intrauterine growth restriction (IUGR).

STUDY DESIGN

A case-control study in singleton livebirths was conducted at the Liverpool Women's Hospital between 2004 and 2005. Cases (n=90) were mothers with an IUGR baby and controls (n=180) those with a normal birthweight infant. Maternal genomic DNA was extracted from buccal smears and PCR (RFLP) was used for genotyping.

RESULTS

Amongst cases, the prevalence of the maternal CYP17 homozygous wild type "A1A1", heterozygous "A1A2" and homozygous "A2A2" variants was 36.7%, 47.7% and 15.6%, which did not differ significantly from their prevalence amongst controls (p=0.6). The proportion with prenatal alcohol exposure was significantly higher in cases than controls (45.6% versus 30.6%, p=0.01). Mean birthweight was significantly lower in mothers with the CYP17 A1A1 genotype compared to those with variant genotypes (A1A2/A2A2) in both the alcohol-exposed (p=0.03) and non-exposed groups (p=0.01). In all women regardless of genotype, IUGR risk increased in mothers exposed to alcohol during pregnancy (OR, 2.9, 95% CI; 1.8-4.2, p=0.01). There was a significant interaction between the CYP17 A1A1 genotype and prenatal alcohol consumption for fetal growth restriction (adjusted OR, 1.4, 95% CI; 1.1-1.9, p=0.04).

CONCLUSION

The association between prenatal alcohol exposure and intrauterine fetal growth restriction was modulated by the maternal CYP17 A1A1 genotype.

Population attributable risk for adverse pregnancy outcomes related to smoking in adolescents and adults

BACKGROUND

Little is known about how population-attributable risks (PAR) for adverse birth outcomes due to smoking differ in adolescent and adult pregnancies.

METHODS

An analysis of community and hospital-based cross-sectional studies in Liverpool was undertaken to estimate the PAR values of low birthweight (LBW), preterm birth, and small for gestational age (SGA) births resulting from pregnancy smoking covering the period between 1983 and 2003. Maternal smoking status and pregnancy outcomes were available for a sample of 12631 women.

RESULTS

The prevalence of maternal pregnancy smoking was 40% in the community sample and 33% in adults and 40% among adolescent pregnancies in the hospital sample. The PAR values (95% CI) associated with LBW, preterm birth and SGA outcomes due to maternal pregnancy smoking in the community sample were 27% (25-30), 13% (11-15) and 25% (23-27), respectively. The PAR values in adults in the hospital sample were 29% (27-31) for LBW, 16% (14-19) for preterm birth and 28% (26-31) for SGA. The corresponding PAR values in adolescents were 39% (34-43), 12% (7-18) and 31% (23-40). The LBW risk attributed to pregnancy smoking in adolescents was significantly higher than for adults (P=0.05).

CONCLUSION

About one-third of LBW, one-quarter of SGA and one-sixth of preterm births could be attributed to maternal smoking during pregnancy. The magnitude of the problem was greater among adolescent pregnancies, among whom a sub-group of mothers with very high risk for adverse birth outcomes due to pregnancy smoking was identified.

Salivary cotinine, doctor-diagnosed asthma and respiratory symptoms in primary schoolchildren

Due to impaired airway function, children are at risk for adverse respiratory symptoms if exposed to environmental tobacco smoke (ETS). A community-based, cross-sectional study of 425 children (5-11 years) attending 15 primary schools in a low socio-economic area of Merseyside/UK was undertaken to investigate the association of adverse respiratory symptoms and ETS exposure using a parent-completed questionnaire and children's salivary cotinine measurements. Overall, 28.9% of children had doctor-diagnosed asthma (DDA) and 11.3% a history of hospital admission for respiratory illnesses. The symptom triad of cough, wheeze and breathlessness (C+W+B+) occurred in 12.6% of children. The geometric mean cotinine level was 0.37 ng/ml (95% CI, 0.33-0.42 ng/ml) and it was estimated that 45.6% of children were ETS exposed. A history of asthma in the family was reported for 9.2% of fathers and 7.2% of mothers. Salivary cotinine level was significantly increased in children with DDA compared to those without (P = 0.002). Cotinine-validated levels [adjusted odds ratio (AOR), 1.8; 95% CI, 1.4-2.5), low socio-economic (disadvantaged) status (AOR, 1.4; 1.1-2.9), child's male gender (AOR, 1.6; 1.1-2.5) and maternal smoking (AOR, 2.2; 1.4-3.1) were significantly associated with DDA. The cotinine-validated level (AOR, 1.4; 1.1-2.9) as well as maternal smoking (AOR, 1.8; 1.1-2.5), were also independently associated with C+W+B+. The use of salivary cotinine as an indicator of ETS exposure could be used to inform parents of exposure risk to their asthmatic children and may help re-enforce deterrent efforts to reduce childhood parental smoking exposure.