A case control study to determine the association between Perthes' disease and the recalled use of tobacco during pregnancy, and biological markers of current tobacco smoke exposure.

AIMS: It is well established that there is a strong association between Perthes' disease and worsening socioeconomic deprivation. It has been suggested that the primary determinant driving this association is exposure to tobacco smoke. This study aimed to examine this hypothesis. PATIENTS AND METHODS: A hospital case-control study (n = 149/146) examined the association between tobacco smoke exposure and Perthes' disease, adjusting for area-level socioeconomic deprivation. Tobacco smoke exposure was assessed by parental questionnaire of smoking habits during pregnancy, and by quantitative assay of current exposure using the urinary cotinine-creatinine ratio, which is a widely used and validated measure of tobacco smoke exposure. RESULTS: The odds of Perthes' disease significantly increased with reported in utero exposure after adjustment for socioeconomic deprivation (maternal smoking odds ratio (OR) 2.06, 95% confidence interval (CI) 1.17 to 3.63; paternal smoking OR 2.09, 95% CI 1.26 to 3.46). The cotinine-creatinine ratio was significantly greater in cases, OR 1.63 (95% CI 1.09 to 2.43), suggesting a greater 'dose' of current tobacco exposure. CONCLUSION: An association exists between tobacco smoke exposure and Perthes' disease but we remain unable to disentangle the association with socioeconomic deprivation. Cite this article: Bone Joint J 2017;99-B:1102-8.

Outcomes in preterm infants.

Preterm birth is defined as birth before 37 completed weeks gestation, and it is estimated that each day, across the world over 41,000 infants are born before this gestational age. The risk of adverse consequences declines with increasing gestational age. While this paper focuses on the consequences of preterm birth, the adverse consequences for infants born at 38 and 39 weeks gestation are also of a higher risk than those for infants born at 40 weeks gestation, with the neonatal mortality risk increasing again in infants born beyond the 42nd week of gestation.

Comorbidities in Perthes' disease: a case control study using the General Practice Research database.

Perthes' disease is an osteonecrosis of the juvenile hip, the aetiology of which is unknown. A number of comorbid associations have been suggested that may offer insights into aetiology, yet the strength and validity of these are unclear. This study explored such associations through a case control study using the United Kingdom General Practice Research database. Associations investigated were those previously suggested within the literature. A total of 619 cases of Perthes' disease were included, as were 2544 controls. The risk of Perthes' disease was significantly increased with the presence of congenital anomalies of the genitourinary and inguinal region, such as hypospadias (odds ratio (OR) 4.04 (95% confidence interval (CI) 1.41 to 11.58)), undescended testis (OR 1.83 (95% CI 1.12 to 3.00)) and inguinal herniae (OR 1.79 (95% CI 1.02 to 3.16)). Attention deficit hyperactivity disorder was not associated with Perthes' disease (OR 1.01 (95% CI 0.48 to 2.12)), although a generalised behavioural disorder was (OR 1.55 (95% CI 1.10 to 2.17)). Asthma significantly increased the risk of Perthes' disease (OR 1.44 (95% CI 1.17 to 1.76)), which remained after adjusting for oral/parenteral steroid use. Perthes' disease has a significant association with congenital genitourinary and inguinal anomalies, suggesting that intra-uterine factors may be critical to causation. Other comorbid associations may offer insight to support or refute theories of pathogenesis.

The cancer incidence temporality index: an index to show temporal changes in the age of onset of overall and specific cancer (England and Wales, 1971-1999).

The theory that increasing cancer incidence rates in developed countries are primarily the consequence of an expanding ageing population and improved diagnostic testing is widely held. In the United Kingdom the proportion of people aged 50 and over has increased by 45% since 1951 and this proportion is set to increase by a further 36% by the year 2031, so the United Kingdom does indeed have an expanding ageing population. However, the increase in cancer incidence affects people across the whole age spectrum. To test the hypothesis that the age of onset of cancer (overall and specific) in England and Wales is decreasing over time we have developed The Cancer Incidence Temporality Index (CITI), which gives a crude measurement of the portion of the population, in which cancer incidence is rising fastest over time: I=(SigmaO(a)/ SigmaE(a))/(SigmaO(a)/SigmaE(a)), where I is the CITI value, O is the observed number of cases and E is the expected number of cases; 'a' and 'b' refer to separate summation ranges for younger and older age groups. Population data and cancer incidence data in England and Wales, 1971-1999 were obtained from the UK Office for National Statistics. The trends in CITI values have been shown graphically for cancer overall and for specific tumour sites. The impact of diagnostic testing is also addressed. The results of this study suggest that the average age of onset of prostate, breast and cervical cancer is temporally decreasing. The study also suggests that for cancer overall the trend for the age of onset of cancer in males has stabilised since 1990 and has started to reverse in females from 1995 despite the expanding ageing population. A similar trend is observed for leukaemias. The CITI analysis for colon cancer shows that the age of onset in both males and females is increasing over time. The trend for ovarian cancer is similar to that for colon cancer. The CITI analysis for NHL in males is similar to that for colon cancer, however, in females the trend stabilised after 1990. The CITI may aid prediction of changes in the age of onset of cancer and thus aid targeted aetiological research. In addition, we suggest the need for a mathematical model, which may measure the changes in the age of onset of cancer in units of time.

Differences between European birthweight standards: impact on classification of 'small for gestational age'.

We describe a quantitative and comparative review of a selection of European birthweight standards for gestational age for singletons, to enable appropriate choices to be made for clinical and research use. Differences between median values at term across standards in 10 regions and misclassification of 'small for gestational age' (SGA), were studied. Sex and parity differences, exclusion criteria, and methods of construction were considered. There was wide variation between countries in exclusion criteria, methods of calculating standards, and median birthweight at term. The lightest standards (e.g. France's medians are 255g lower than Norway's medians) were associated with fewer exclusion criteria. Up to 20% of the population used in the construction of the Scottish standard would be classified as SGA using the Norwegian standard. Substantial misclassification of SGA is possible. Assumptions about variation used in the construction of some standards were not justified. It is not possible to conclude that there are real differences in birthweight standards between European countries. Country-based standards control for some population features but add misclassification due to the differing ways in which standards are derived. Standards should be chosen to reflect clinical or research need. If standards stratified by sex or parity are not available, adjustments should be made. In multinational studies, comparisons should be made between results using both a common standard and country-based standards.

Determining Liverpool adolescents' beliefs and attitudes in relation to oral health.

Poor oral health is an important public health issue. Adolescents represent a challenging group in terms of oral health because they have vulnerable permanent teeth erupting at a time when they are establishing their independence from parental influence. Preventing oral disease by attempting to influence the behaviours that impact adversely on oral health requires an understanding of the attitudes and beliefs that underpin those behaviours. Very few studies have investigated adolescents' attitudes and beliefs in relation to dental issues. This study aimed to examine the attitudes and beliefs of adolescents towards dentistry and oral disease in order to inform future health promotion interventions. Data were collected through focus groups involving 22 13- to 14-year olds from selected secondary schools in Liverpool. A thematic analysis was applied to the data. The themes identified illustrated the attitudes and beliefs of adolescents in relation to oral health and demonstrated how adolescents justify and personally operationalize these attitudes and beliefs. A need to encourage this group to take action to perform oral health behaviours was demonstrated.

Issues and experience around the Paediatric Register of Inflammatory Bowel Disease.

Accurate epidemiological data is one of the most important tools to elucidate disease aetiology and natural history. Disease registers are the cornerstone of this process. The importance of registers in facilitating an efficient health service is clear. We have been engaged in the development of a register of paediatric inflammatory bowel diseases, and in this article we present a general overview of registers and of lessons we have learnt along the way.

The epidemiology of sudden infant death syndrome.

BACKGROUND: Twins compared to singletons are at increased risk of sudden infant death syndrome (SIDS). AIMS: To compare the epidemiology of SIDS in twins and singletons and to test the hypothesis that monozygous (MZ) were at greater risk of SIDS than dizygous (DZ) twins. METHODS: Data from the Office for National Statistics on all registered live births and infant deaths with registered cause of death "sudden unexpected death in infancy" in England and Wales from 1993 to 1998 were obtained, together with the registered birth weight and, for twins, whether they were of like or unlike sex. RESULTS: The crude relative risk of SIDS in twins is twice that in singletons. There has been a significant temporal decline in SIDS mortality. There is also a significant increase in risk with decreasing birth weight for both twins and singletons. The birth weight specific risk of SIDS in all except for those > or =3000 g is greater in singletons than in twins. There is no significant difference in risk of SIDS in like compared with unlike sex twins. CONCLUSIONS: In spite of a lower risk of SIDS in twins compared with singletons for each birth weight group <3000 g, one component of the higher crude relative risk of SIDS in twins is attributable to the higher proportion of twins that are of low birth weight. A second component is the higher risk in twins compared with singletons for those of birth weight > or =3000 g. Like sex are at no greater risk than unlike sex twins, which suggests that zygosity is not a significant factor in SIDS.

St Vincent's Declaration 10 years on: outcomes of diabetic pregnancies.

AIMS: To monitor pregnancies in women with pregestational Type 1 diabetes for pregnancy loss, congenital malformations and fetal growth parameters, in a geographically defined area in the north west of England. METHODS: Population cohort study of 547 pregnancies in women with Type 1 diabetes from maternity clinics in 10 centres over a 5-year period (1995-1999 inclusive). Main outcome measures were numbers and rates of miscarriages, stillbirths, neonatal and post-neonatal deaths; prevalence of congenital malformations; birth weight in relation to gestational age. RESULTS: Among 547 pregnancies, there were six (1.1%) pairs of liveborn twins, 439 (80.3%) liveborn singletons; 72 (13.2%) spontaneous abortions, 14 (2.6%) stillbirths and 16 (2.9%) terminations. Four of the terminations were performed because of congenital malformations. Both the stillbirth rate (30.1/1000 total births (95% confidence interval (CI) 16.6-50.0)), and prevalence of congenital malformations (84.3/1000 live births (95% CI 60.3-113.8)) were significantly higher than the local population (P < 0.001). When corrected for gestational age, mean birth weight in the sample was 1.3 sd greater than that of infants of non-diabetic mothers (P = 0.12). Infants with congenital malformations weighed less than those without. CONCLUSION: In an unselected population, the infants of women with pregestational Type 1 diabetes mellitus have 6.4 times the reported risk of a congenital malformation and 5.1 times the reported risk of perinatal mortality than infants in the general population. Further improvements in the management of diabetes and pregnancy in these women are needed if the St Vincent's Declaration target is to be met.

The effects of assisted reproduction on the trends and zygosity of multiple births in England and Wales 1974-99.

Assisted reproductive techniques have led to an increase in the proportion of maternities that are multiple. Though predominantly dizygotic, they are at greater risk of monozygotic division than those spontaneously conceived. England and Wales data 1974-99 on stillbirths and livebirths were analysed for 4 periods: 1974-80 (pre-assisted reproduction; 1982-8; 1989-91 (pre-redefinition of stillbirth); 1993-9 (post-redefinition of stillbirth). For twin data, Weinberg's rule was applied to estimate the proportions that were mono- (MZ) and dizygotic (DZ). Compared with the period before assisted reproduction, the most recent period shows an increase in twin maternities of 3.81 per 1,000 comprised of 3.22 (95% CI 3.10 to 3.33; p < 0.0001) DZ and 0.60 (95% CI 0.51 to 0.68; p < 0.0001) MZ twins. It is estimated that 15.7% of assisted reproduction twins are MZ. Higher order multiple births showed an increase of 3.06 (95% CI 2.85 to 3.29; p < 0.0001) per 10,000 maternities. Stillbirth rates in MZ twins are of the same order of magnitude as those in higher order multiple births but higher than those in DZ twins. The improvement in stillbirth rates over the 26 year study period is of the same order magnitude in singletons, DZ and MZ twins and higher order multiples. Assisted reproduction has led to a significant increase in the proportion of MZ twins. These are at high risk of fetal death and this needs to be considered when local stillbirth and perinatal mortality rates are used in auditing obstetric services.

Child health statistics review, 1998.

There is a broad spectrum of data that can be used to describe the health of young people in the UK. These data are of varying quality, reflecting in part the methods used to collect them. However, it is often frustrating trying to locate information relevant to young people: so many of the apparently obvious sources of data, such as routine surveillance data, are either not collated centrally, or are not related to a defined population. Perhaps, with the recently introduced changes in commissioning health services within England and Wales, local pressure will bring about an improvement in this.

Outcomes of pregnancy in insulin dependent diabetic women: results of a five year population cohort study.

OBJECTIVE: To monitor pregnancies in women with pre-existent insulin dependent diabetes for pregnancy loss, congenital malformations, and fetal growth in a geographically defined area of north west England. DESIGN: Population cohort study. SETTING: 10 maternity units in Cheshire, Lancashire, and Merseyside which had no regional guidelines for the management of pregnancy in diabetic women. SUBJECTS: 462 pregnancies in 355 women with insulin dependent diabetes from the 10 centres over five years (1990-4 inclusive). MAIN OUTCOME MEASURES: Numbers and rates of miscarriages, stillbirths, and neonatal and postneonatal deaths; prevalence of congenital malformations; birth weight in relation to gestational age. RESULTS: Among 462 pregnancies, 351 (76%) resulted in a liveborn infant, 78 (17%) aborted spontaneously, nine (2%) resulted in stillbirth, and 24 (5%) were terminated. Of the terminations, nine were for congenital malformation. The stillbirth rate was 25.0/1000 total births (95% confidence interval 8.9 to 41.1) compared with a population rate of 5.0/1000, and infant mortality was 19.9/1000 live births (5.3 to 34.6) compared with 6.8/1000. The prevalence of congenital malformations was 94.0/1000 live births (63.5 to 124.5) compared with 9.7/1000 in the general population. When corrected for gestational age, mean birth weight in the sample was 1.3 standard deviations greater than that of infants of non-diabetic mothers. Infants with congenital malformations weighed less than those without. CONCLUSION: In an unselected population the infants of women with pre-existent insulin dependent diabetes mellitus have a 10-fold greater risk of a congenital malformation and a fivefold greater risk of being stillborn than infants in the general population. Further improvements in the management of pregnancy in diabetic women are needed if target of the St Vincent declaration of 1989 is to be met.

Child health statistical review, 1996.

There is much evidence that the children born in the last decade of the 20th century are healthier and living longer than children born earlier this century, and that children born too small or too soon are now more likely to reach adulthood than similar children born 10 or 20 years ago. Yet measures of social disadvantage (poverty, underachievement in education, lone parenthood) are increasing, putting this generation of children at higher risk of morbidity later in life.

The changing epidemiology of cerebral palsy.

AIM: To determine the prevalence of cerebral palsy in a specific population. METHODS: Multiple sources of ascertainment were used to create and maintain a register of all cases of cerebral palsy born to mothers resident in the counties of Merseyside and Cheshire in the years 1966 to 1989. Denominator data of infant births and deaths from 1966 to 1981 were obtained from statutory notifications made to health authorities and, for the period 1982-89, from statutory birth and death registrations. Over 1500 cases formed the database for the study. RESULTS: The prevalence of cerebral palsy has increased among all the low birthweight groups with, most recently, an increase in infants weighing < 1000 g at birth. Low birthweight infants now comprise about 50% of all cases of cerebral palsy; in the early years of the study they comprised about 32% of all cases. The proportion of cerebral palsy by clinical type has changed among low birthweight babies, with relatively fewer cases with diplegia and a concomitant increase in the proportion with hemiplegia. An increase in the severity of functional disability, determined by the proportion of children with severe learning, manual, and ambulatory disabilities, was also found. CONCLUSIONS: The change in the epidemiology of cerebral palsy has implications for the aetiology of the condition, and for health, educational, and social service provision.