Trends in early gestation stillbirths and neonatal deaths in New South Wales, Australia 2002-2019.

BACKGROUND: Little research has focused on understanding trends in early gestation (20-27 weeks) stillbirths and neonatal deaths. AIMS: To examine trends in early gestation stillbirths and neonatal deaths in New South Wales (NSW), Australia. MATERIALS AND METHODS: Population-based cohort study of all births ≥20 weeks gestation among female NSW residents during 2002 to 2019, induced pregnancy terminations excluded. Stillbirth rates by gestational age and birth year were calculated per 1000 fetuses-at-risk (FAR). Neonatal death rates by gestational age and birth year were calculated per 1000 live births. Linear regression was used to examine trends in stillbirth and neonatal death rates among all, singleton and twin births. RESULTS: Declining trends in early gestation stillbirth and neonatal death rates were found. Stillbirth rates decreased from 1.9 and 0.9/1000 FAR in 2002 to 1.6 and 0.7 in 2019 for 20-23 and 24-27 week groups, respectively. Neonatal rates decreased from 940 and 315/1000 live births in 2002 to 925 and 189 in 2019 for the 20-23 and 24-27 week groups, respectively. Among singleton births, declining trends in stillbirth and neonatal death rates across all age groups were observed, except for 37-38 week stillbirths. No trends in twin stillbirth rates were found across gestational age groups, although a decreasing trend was observed for 20-23 week twin neonatal deaths. CONCLUSIONS: Trends in early gestation stillbirth and neonatal deaths have declined in recent decades in NSW but further efforts are needed to reduce both early and late gestation stillbirth rates among twin births.

Does Particulate Matter Modify the Short-Term Association between Heat Waves and Hospital Admissions for Cardiovascular Diseases in Greater Sydney, Australia?

Little is known about the potential interactive effects of heat waves and ambient particulate matter on cardiovascular morbidity. A time-stratified case-crossover design was used to examine whether particulate matter (PM10) modifies the association between heat waves and emergency hospital admissions for six cardiovascular diseases in Greater Sydney, Australia during the warm season for 2001-2013. We estimated and compared the effect of heat waves on high- and low-level PM10 days at lag0-lag2, adjusting for dew-point temperature, ambient ozone, ambient nitrogen dioxide, and public holidays. We also investigated the susceptibility of both younger (0-64 years) and older populations (65 years and above), and tested the sensitivity of three heat wave definitions. Stronger heat wave effects were observed on high- compared to low-level PM10 days for emergency hospital admissions for cardiac arrest for all ages combined, 0-64 years and 65 years and above; conduction disorders for 0-64 years; and hypertensive diseases for all ages combined and 0-64 years. Overall, we found some evidence to suggest that PM10 may modify the association between heat waves and hospital admissions for certain cardiovascular diseases, although our findings largely differed across disease, age group, lag, and heat wave definition.