Infant Mortality Analysis Update (2) 2011 Gestation Birthweight Age of Mother Ethnicity Cause of death Jonnie Dance – Senior Public Health Analyst Teresa Keegan - Public Health Information Analyst Including analysis conducted by: Helen Brown – Head of Intelligence Public Health Simon Chappell – Public Health Trainee Analyst

Glossary Gestationlength of pregnancy Paritynumber of births to one woman Pre-term birth birth prior to 37 full weeks gestation Low Birth Weightbirthweight of infant < 2.5kg Very Low Birth Weightbirthweight <1.5Kg Deprivation quintilePost-coded localities ranked according to the Index of Multiple Deprivation and divided into five levels across Bradford

Glossary cont… Infant mortalityDeath of a live born infant prior to one year of age. Infant mortality ratenumber of infant deaths (IMR)per 1,000 live births Neo-natal mortalitydeath of live born infant prior to 28 days of age Post-neonatal mortalityDeath of an infant between 28 days to one year of age Stillbirthinfant that dies prior to birth and after 24 weeks gestation Still birth rateNumber of stillbirths per 1000 stillbirths and live births

Gestation – key points There has been relatively little change in the proportion of premature births over the last 15 years - between 7-9%. There is a deprivation gradient with more premature births in the most deprived areas. There has been a slight increase, since 2003, in infant mortality rates amongst full term births. There has been a steady increase in stillbirth rates amongst full term births since 1996.

Proportion of all births by gestation category, Bradford and E&W Little overall change in proportion for each category of low gestation although a decrease in the proportion of week babies in recent years

Premature birth rate by deprivation quintile over time (5-year rolling) Deprivation gradient seen for premature births Relatively little change seen between the most and least deprived

Mortality rates for premature and full term births Infant mortality rates have risen in full term births since Still birth rates have steadily risen across the whole time period, with the rate being significantly higher than the rate

Gestation – key points There has been relatively little change in the proportion of premature births over the last 15 years - between 7-9%. There is a deprivation gradient with more premature births in the most deprived areas. There has been a slight increase, since 2003, in infant mortality rates amongst full term births. There has been a steady increase in stillbirth rates amongst full term births since 1996.

Birthweight (BW) – Key points There is a clear deprivation gradient seen for low and very low BW babies. Mortality is much higher for low BW babies (approx 10x higher than those weighing > 2500g) and much higher for very low BW (approx 10x higher than low BW) Infant mortality rates have changed little over the last 15 years for ‘normal’ BW babies but have decreased for Low BW and very low BW babies. Still birth rates have increased across all birth weights but most for ‘normal’ BW babies.

Proportion of low birthweight births by deprivation quintile (3-year rolling) Clear deprivation gradient with a higher proportion of low weight births ( g) in the more deprived areas. Excludes v low birthweight – similar but less vivid picture

Distribution of birthweight for each deprivation quintile, Gradient seen with lower BW babies for the most deprived areas

Mortality Rates for different birthweight babies, Bradford and E&W, There is a large difference in mortality rates between normal, low and very low BW (approximately a factor of 10 difference between each category).

Mortality rates for >2500g BW babies Overall mortality for >2500g babies has not statistically significantly changed since 1996 – Still birth rates have increased consistently, but this is not statistically significant

Birthweight (BW) – Key points There is a clear deprivation gradient seen for low and very low BW babies. Mortality is much higher for low BW babies (approx 10x higher than those weighing > 2500g) and much higher for very low BW (approx 10x higher than low BW) Infant mortality rates have changed little over the last 15 years for ‘normal’ BW babies but have decreased for Low BW and very low BW babies. Still birth rates have increased across all birth weights but most consistently for babies with a BW >2500g. Stillbirths – rising in full-term, > 2500g babies

Age of mother – key points Bradford Infant Mortality rates are higher across all age bands than E&W rates. IM rates in children born to younger mothers and older mothers is falling – but not so in the band which appears to be most adrift from national levels.

Ratio of Bradford to England Mortality rates by age of mother, Biggest differences in rates compared to Eng&Wales are seen for mothers aged Even though rates higher for 40+ it is the women aged that have significantly higher than expected still births in Bradford compared to E&W

Ratio of Bradford Mortality rates by age of mother, (compared to ) Across most age bands mortality rates have decreased (although not sig.). Mothers aged however have seen an increase in infant mortality and still birth rates. Age of Mothers 40+ have seen the biggest decrease in mortality, and this is significant for still births.

Infant mortality rate by age of mother Rates higher than England and Wales across all mother ages, and highest for mothers under 20 years. Large fluctuation for 40+ mothers due to small numbers

Age of mother – key points Bradford Infant Mortality rates are higher across all age bands than E&W rates. IM rates in children born to younger mothers and older mothers is falling – but not so in the band which appears to be most adrift from national levels.

Ethnicity – key points Two biggest groups are White and Pakistani Infant Mortality rates higher in Pakistani and ‘Other’ populations. ‘Other’ ethnicities are: AfricanAny other Asian background Any other Black backgroundAny other Ethnic Group Any other Mixed backgroundBangladeshi CaribbeanChinese IndianOther Asian Background Other Black backgroundOther Ethnic group Other Mixed backgroundWhite and Asian White and Black AfricanWhite and Black Caribbean (Office for National Statistics Classification)

Infant mortality by Ethnic group, (Eng&Wales 2005) Infant mortality rates are significantly higher for the White population in Bradford than in the White population of E&W. The rate for the Pakistani population is also higher than nationally although not statistically significant.

Neonatal and Post neonatal mortality rates by Ethnic group, (Eng&Wales 2005) Although a higher proportion of deaths are neonatal (60%), Post neonatal mortality rates for all ethnic groups are more markedly higher than nationally. NeonatalPost neonatal

Ethnicity – key points Infant Mortality rates are higher in Pakistani and ‘Other’ populations. IMR in the white population of Bradford is significantly higher than that of white popn E&W

Cause of death Cause of death data is linked in to the master table from ONS deaths and is based on ICD10 coding. The categories of death used in this analysis are: –Congenital anomalies –Infections –Sudden infant deaths –Ante partum infections –Asphyxia, anoxia or trauma –Immaturity related conditions –External conditions –Other conditions –Other specific conditions

Cause of death – key points Two main causes of death are Congenital Anomalies and Immaturity Related Conditions. The principle causes are most prevalent in the most deprived areas. Infant Mortality rates higher in Pakistani and ‘Other’ populations.

Actual and Expected number of deaths, by cause, and Calculated by multiplying the Bradford average yearly births by E&W rates. Most excess deaths seen for ‘congenital anomalies’ and ‘immaturity related conditions’.

Infant mortality rate by cause of death compared to E&W, and Compared to Eng&Wales, there are significantly higher mortality rates due to ‘congenital anomalies’, ‘infections’ and ‘immaturity related conditions’ as well as other causes

Infant mortality rate by cause and deprivation quintile, Higher rates of all main causes of death in the most deprived quintiles

Infant mortality rate by cause and deprivation quintile,

Cause of death by ethnicity, Higher infant mortality rate for Pakistani population largely attributable to higher rates of ‘Congenital anomalies’ and ‘Immaturity related conditions’. Congenital Anomalies Immaturity

Cause of death by ethnicity,

Cause of death – key points Since 2003 there is now a significant difference in the Bradford IMR for ‘anoxia, asphyxia and trauma’. Major excess cause of death for Pakistani mothers is congenital anomalies

Persistent deprivation distribution for all aspects of infant mortality – LBW, Pre-term birth and major causes of death Rise in stillbirths, significantly so in full-term births over 15 years The pattern of risk of poor birth outcome by age of mother is different in Bradford to England and Wales – in Bradford women aged 24 – 34 remain at risk The numbers of deaths categorised as ‘other’ remains high Significant difference in the IMR from cause of death ‘Anoxia, asphyxia and trauma’ between Bradford and E&W (change from the BDIMC analysis) Change in mortality rates in the 1 st and 2 nd generation Pakistani mothers. Key aspects