Chapter 4 - How Healthy Are Our Young Children?
Highlights
In Canada, in 2002/03:
- 81% of babies were born at a healthy weight.
- 92.5% of children were born full term.
- The infant mortality rate was 5.4 deaths per 1,000 live births.
- 84.2% of children from birth to 3 years of age in Canada were breastfed during infancy.
- 9.4% of children from birth to 5 years of age had asthma that was diagnosed by a physician.
- Sympathetic nervous system tumors were the most common type of cancer among children under 1 year of age.
- Leukemia was the most common type of cancer among young children from 1 to 4 years of age.
- The majority of injuries to young children for which they were treated at a hospital were caused by accidental falls.
4.1 Healthy Birth Weight22
... 8 out of 10 children in Canada are born at a healthy weight
A healthy birth weight is defined as between 2,500 and 4,000 grams. Children weighing less than 2,500 grams are considered to be of low birth weight, and children weighing more than 4,000 grams are considered to be of high birth weight. From 2000 to 2002, the proportion of children born at a healthy birth weight remained constant at 81%. As such, the proportion of children born at a low or high birth weight has also remained relatively constant within the same time period: from 5.5% to 5.8% for low birth weights, and 13.8% to 13.2% for high birth weights for 2000 and 2002 respectively.
For babies born at a low birth weight, the percentage of females was consistently higher than males in all years. This was most noticeable in 2002, when the percentage of females born at a low birth weight was 6.0%, compared with 5.4% of males.
The proportion of males born at a high birth weight was consistently higher than females for all years between 2000 and 2002. In 2002 specifically, the proportion of young male children born at a high birth weight was 16.2%, compared with only 10% of young female children in the same year.
…while internationally
Compared to other member countries of the Organization for Economic Co-Operation and Development (OECD), Canada had one of the lowest percentages of children born at a low birth weight, at 5.8% in 2002.
Why is this important?
Chapter 4
A child's weight at birth is a key indicator of development both in utero and after birth. Low birth weight has long been a public health concern because of its relationship to poor infant health and mortality. Children born at a low birth weight face a number of potential problems, including an increased risk of dying during the first year of life, developmental disabilities and disease.23 Mothers in poor health, with unhealthy lifestyles or living in difficult economic circumstances, are at greater risk of giving birth to an infant of low birth weight.24 Conversely, children born at a high birth weight are at greater risk of death within the first month of life, injuries during birth, and intellectual and developmental problems.25
4.2 Pre-Term Births26
... Most Canadian children are born at 37 weeks of gestation or later
In 2002, 92.5% of live births were full term. A full-term birth has been defined as 37 weeks of gestation or later. Pre-term births (before 37 weeks of gestation) continued to be more prevalent among males than females (7.9% of all boys compared with 7% of all girls in 2002).
Why is this important?
Babies born prematurely weigh less than a child born at term. All pre-term babies are at risk for serious health problems due to inadequate physical development in utero, resulting in such things as respiratory distress syndrome, apnea, bleeding in the brain, jaundice, anemia, chronic lung disease and infections, long-term disabilities and even death. The earlier the baby is born, the more risk he or she faces. In light of this, many pre-term babies are kept under hospital supervision to minimize long-term impacts.
4.3 Infant Mortality27
… Canada's infant mortality rate has remained relatively stable
The infant mortality rate refers to the number of children who die within the first year of life, excluding still births. In 2002, the infant mortality rate was 5.4 deaths per 1,000 live births, up slightly from 5.3 in 1999 and 2000 and 5.2 in 2001.Males have a higher infant mortality rate than females. In 1999, the male infant mortality rate was 5.7 deaths per 1,000 live births compared with 4.8 deaths per 1,000 live births for females. This trend continued for 2002, when the rates were 5.8 and 4.9 respectively.
….. while internationally
Canada ranked 21 out of 27 OECD countries in terms of infant mortality in 2002. Iceland and Sweden reported the lowest rates at 2.2 and 2.8 deaths per 1,000 live births, respectively.28 It should be noted that the infant mortality rate, of 5.4 deaths per 1000 live births, in Canada in 2002 was lower than the OECD average of 6.6 deaths per 1,000 live births.29
Why is this important?
Infant mortality is considered a key component in determining standard of living because it provides insight into both social well-being and health status. It is also the most widely available accurate measure of infant health. There are numerous possible causes of infant death — congenital anomalies (for example, heart and cardiovascular conditions), respiratory distress syndrome and Sudden Infant Death Syndrome (SIDS), for example.30 The underlying risk factors for infant death include low birth weight (especially when associated with pre-term delivery31), maternal/paternal smoking (increases the risk of SIDS, infections and other adverse outcomes),32 and family and social environments (poverty, overcrowded house conditions and parental well-being, including alcohol and substance abuse).33
4.4 Breastfeeding
…. 8 out of 10 children in Canada are breastfed during infancy
In 2002/03, the percentage of children from birth to 3 years of age who were either being breastfed or who had been breastfed was 84.2%, up from 79.9% in 1998/99.
More children living in urban centres were being breastfed than their rural counterparts. In 1998/99, 80.9% of urban mothers reported breastfeeding their child compared with 72.9% of mothers living in rural areas. By 2002/03, these figures had increased for both areas, with the percentage in urban areas remaining higher (85.1% compared with 77.5% in rural areas).
The average duration of breastfeeding is also on the rise. Of the children who had been breastfed, 36.4% were reported to have breastfed for seven months or longer. This rate is up from the 34% reported in 1998/99 and the 32.4% reported in 2000/01.
Why is this important?
The optimal duration for breastfeeding a baby is six months or more.34 Experts agree that human breast milk contains the perfect balance of nutrients a baby needs to grow. In addition, babies who are breastfed are also receiving the positive stimulation of touch, sight, sound, taste, warmth and smell — all of which contribute to positive child development. As well, research has consistently shown that breastfeeding protects against gastrointestinal and respiratory infections later in life. Researchers are now exploring the role that breastfeeding may play in providing protection against chronic adult conditions such as obesity, coronary heart disease, and Type 1 and Type 2 diabetes.35
4.5 Asthma
... Less than 10% of children from birth to 5 years of age had asthma that was diagnosed by a physician
In 2002/03, 9.4% of children from birth to 5 years of age were reported to have asthma that was diagnosed by a physician compared with 10.2% in 2000/01 and 9.9% in 1998/99.
Asthma continues to be more prevalent among males than females. In 2002/03, 11.6% of male children were reported to have asthma compared with 7.1% of female children. Asthma is also more prevalent in urban centres than in rural areas, with 9.6% of children living in urban centres reported to have asthma in 2002/03 compared with 8% of children living in rural settings.
Why is this important?
Asthma is a serious, sometimes life-threatening respiratory disease that is one of the most prevalent chronic conditions among children in Canada and affects a substantial proportion of children worldwide. In severe form, it may limit a child's ability to participate in daily activities and can influence his or her overall development. It can also be fatal.
Though not all children with allergies will have asthma, allergens are a common trigger for attacks. Allergens such as dust mites, animal dander and mould can all cause asthmatic reactions in children who are sensitive to them. Second-hand smoke and contact with insecticides are two other common causes that are often cited as the most preventable.36
4.6 Childhood Cancer37, 38
Of all children under the age of 18, cancer is most prevalent in children from birth to 5 years of age.39 The types of cancers occurring in young children are also quite different from those occurring in adults, and tend to occur in different parts of the body, including within the nervous and lymphatic systems.40
… Sympathetic nervous system tumours were the most commonly diagnosed type of cancer in children under 1 year of age.
From 1998 to 2000, approximately 280 new cases of cancer were diagnosed in children under 1 year of age, representing an incidence rate of 27.5 new cases per 100,000 children. The four most common types were sympathetic nervous system tumours41 (21.4% of total), leukemia (17.9%), central nervous system tumours42 (12.5%) and retinoblastoma43 (10.7%). Combined, these cancers accounted for 62.5% of all newly diagnosed cases in children under 1 year of age. The difference between the genders was negligible.
… Leukemia accounted for almost half of all new cases diagnosed in children between 1 and 4 years of age.
Approximately 940 new cases of cancer were diagnosed in children between 1 and 4 years of age during the period from 1998 to 2000, representing an incidence rate of 21.1 new cases per 100,000 children. Leukemia was the most common (45.7% of total), followed by central nervous system tumours (16.0%), sympathetic nervous system tumours (10.1%) and soft-tissue sarcomas44 (3.7%). These cancers represented 75.5% of all new cases from 1998 to 2000 for this age group. There is a notable difference between the genders in the number of newly diagnosed cases of leukemia; males represented 60.5% of the cases diagnosed, while females represented 39.5%.
| Table 1 Cancer: Number of New Cases and Rate per 100,000 Population 45 |
||||||
| New Cases in Children Less Than 1 Year of Age, Canada, 1998—2000 | ||||||
| Males | Females | Both | ||||
| Number | Rate | Number | Rate | Number | Rate | |
| Leukemia | 20 | 4.2 | 30 | 5.6 | 50 | 4.9 |
| Central Nervous System Tumours | 15 | 2.7 | 20 | 4.2 | 35 | 3.4 |
| Sympathetic Nervous System Tumours | 30 | 5.3 | 30 | 6.4 | 60 | 5.9 |
| Retinoblastoma | 15 | 3.2 | 10 | 2.4 | 30 | 2.8 |
| Soft-tissue Sarcomas | 15 | 2.7 | 5 | 1.4 | 20 | 2.1 |
| Total | 140 | 26.5 | 140 | 28.4 | 280 | 27.5 |
| New Cases in Children 1-4 Years of Age, Canada 1998—2000 | ||||||
| Males | Females | Both | ||||
| Number | Rate | Number | Rate | Number | Rate | |
| Leukemia | 260 | 11.3 | 170 | 7.9 | 430 | 9.6 |
| Central Nervous System Tumours | 90 | 3.9 | 60 | 2.8 | 150 | 3.4 |
| Sympathetic Nervous System Tumours | 50 | 2.1 | 45 | 2.2 | 95 | 2.2 |
| Retinoblastoma | 15 | 0.7 | 15 | 0.6 | 30 | 0.7 |
| Soft-tissue Sarcomas | 20 | 0.8 | 15 | 0.8 | 35 | 0.8 |
| Total | 540 | 23.5 | 410 | 18.6 | 940 | 21.1 |
| Source: Treatment and Outcome Surveillance (TOS) Surveillance System, Canadian Childhood Cancer Surveillance and Control Program. | ||||||
Why is this important?
Cure rates for childhood cancers are much higher than for most adult cancers, and more than 70% of all children's cancers are completely cured.46 As young children's bodies are still in the developmental stages, the after-effects of cancer treatment are often more pronounced, and can result in significant health and cognitive problems as they continue to grow. The after-effects are often absent when therapy ends but manifest later in life.47 For example, chemotherapy delivered into the spinal column has been associated with learning disabilities, affecting visual motor skills, memory, attention and non-verbal skills such as math. Treatment can affect growth, sexual development, and cardiovascular and respiratory health. In addition, childhood cancer survivors have a small but increased risk of developing a second type of cancer during their lifetime.48
4.7 Injury49 Hospitalization
In children under 1 year of age, injuries requiring hospitalization have dropped
There were 1,268 unintentional injuries of children under 1 year of age in 2002/03 that resulted in hospitalization (386.4 per 100,000). The four most common causes were falls,50 poisoning, suffocation and contact with a hot object or substance. From 1998/99 to 2002/03, these four causes consistently accounted for the majority of injuries requiring hospitalization for this age group. Unintentional injuries of male and female children under 1 year of age declined from 438.9 per 100,000 in 1998/99 to 386.4 per 100,000 in 2002/03.51 Male children tend to have higher rates of injury requiring hospitalization across all categories. In particular, males were much more likely to be hospitalized as a result of falls (a rate of 219.2 per 100,000) than were females (a rate of 171.4 per 100,000).
For children from 1 to 4 years of age, the rate of hospitalization for injuries has also dropped
In children from 1 to 4 years of age, the rate of hospitalization for unintentional injuries has declined for 5 consecutive years, from 465.3 in 1998/99 to 383.5 per 100,000 in 2002/03.52 In 2002/03, there were 5,362 of these injuries in this age group, with the most common being falls, followed by poisoning, being struck by/against an object, person or thing, and coming into contact with a hot object or substance. Similar to children less than 1 year age, falls remain the most common injury requiring hospitalization.
In 2002/03, males had a much higher rate of unintentional injury requiring hospitalization (435.5) than females (329.1). In general, males had higher rates of injury hospitalization than females in all years from 1998/99 to 2002/03, with the most pronounced difference in the injuries related to falls.
Why is this important?
Injuries during childhood can have significant long-term implications for the well-being and development of a child. Pain and/or loss of motor or cognitive function as a result of injury can adversely affect the quality of life of the child.53 The nature of the injury ultimately determines the extent of life-long impacts, but even mild injuries can have dramatic effects. For example, mild brain injuries can result in problems with cognitive development and memory that are permanent, which is especially troubling for young children. Depending on the severity of the childhood injury, significant effects can also be felt by the family. The costs associated with rehabilitation and medical care can often affect a family's financialsituation, while time demands related to caring for the injured child can also create stress in the home. The attention required by parents to care for the special needs associated with injury of the child can affect the overall care that parents are able to provide to other family members, including each other.54, 55
22 Birth-related indicators for 2000 should be interpreted with caution at the national level due to concerns with the quality of some provincial birth registration data.
23 Government of Canada (2002). Healthy Canadians — A Federal Report on Comparable Health Indicators 2002. Ottawa: Health Canada.
24 Ibid.
25 MacMillan, H. et al. (1999). "Chapter 1 — Children's Health." First Nations and Inuit Regional Health Survey. Ottawa: First Nations and Inuit Regional Health Survey National Steering Committee.
26 Birth related indicators for 2000 should be interpreted with caution at the national level due to concerns with the quality of some provincial birth registration data.
27 Birth-related indicators for 2000 should be interpreted with caution at the national level due to concerns with the quality of some provincial birth registration data.
28 Organisation for Economic Co-operation and Development (OECD) (2004). OECD Health Data 2004: A Comparative Analysis of 30 Countries, 2004 Edition. Paris: OECD.
29 Public Health Agency of Canada analysis of data presented in Organisation for Economic Co-operation and Development (OECD) (2004). OECD Health Data 2004: A Comparative Analysis of 30 Countries, 2004 Edition. Paris: OECD.
30 Canadian Perinatal Surveillance System (CPSS) (March 1998) "Canadian Perinatal Surveillance System Fact Sheets: Infant Mortality". Ottawa: Public Health Agency of Canada. Available at: http://www.phac-aspc.gc.ca/rhs-ssg/factshts/mort_e.html.
31 Office for National Statistics (2001). "Infant and Perinatal Mortality by Social and Biological Factors, 2000." Health Statistics Quarterly. 12: 78—82.
32 Kramer, M. et al. (2000). "Socio-Economic Disparities in Pregnancy Outcome: Why do the Poor Fare so Poorly?" Pediatric and Perinatal Epidemiology. 14(3): 194—210.
33 Guildea, Z., D. Fone, F. Dunstan et al. (2001). "Social Deprivation and the Causes of Still-Birth and Infant Mortality." Archives of Disease in Childhood. 84: 307—310.
34 Canadian Institute of Child Health (2000). The Health of Canada's Children: A CICH Profile, 3rd Edition. Ottawa: Canadian Institute of Child Health.
35 Kramer, M. S. (2005). "Breastfeeding Promotion and Early Childhood Development: Comments on Woodward and Liberty, Pérez-Escamilla, Lawrence and Greiner." R. Tremblay, R. Barr and R. Peters (eds.) Encyclopedia on Early Childhood Development. 2005:1—5. Montreal: Centre of Excellence for Early Childhood Development. Available at: http://www.excellence-earlychildhood.ca/documents/KramerANGxp.pdf.
36 For a more thorough discussion, see http://www.childenvironment.org/factsheets/asthma.htm.
37 Acknowledgement for assistance in developing this section is extended to Kendra Carswell, University of Ottawa.
38 The data presented represent the most current childhood cancer data available from the Canadian Childhood Cancer Surveillance and Control Program.
39 The Canadian Childhood Cancer Surveillance and Control Program: Facts and Figures. Available at: http://www.phac-aspc.gc.ca/ccdpc-cpcmc/program/cccscp-pcslce/facts_e.html.
40 Childhood Cancer Foundation: Candlelighters Canada, "Overview: Childhood Cancers Are Unique," Available at: http://www.candlelighters.ca/facts/index.html.
41 Sympathetic nervous system tumours develop in the nerve fibres that run alongside the spinal cord, in clusters of nerve cells called ganglia at certain points along the path of the nerve fibres, and in nerve-like cells found in the medulla (centre) of the adrenal glands.
42 Tumours of the central nervous system develop in the brain or spinal cord.
43 Retinoblastoma is cancer that develops from an immature retina — th e part of the eye responsible for detecting light and colour.
44 Sarcomas are malignant (cancerous) tumours that develop in soft tissue (including muscles and tendons — bands of fibre that connect musc les to bones), fibrous tissues, fat, blood vessels, nerves and synovial tissues (tissues around joints).
45 Totals were rounded as follows: counts between 0 and 99 to the nearest 5; counts between 100 and 999 to the nearest 10; counts between 1,000 and 1,999 to the nearest 50; and counts greater than or equal to 2,000 to the nearest 100. All rates are calculated per 100,000 population (by age grouping) and were rounded to the nearest 10. Please note that totals may not equal the sum of their parts due to rounding. Also, cell counts of less than 5 have been suppressed.
46 Childhood Cancer Foundation: Candlelighters Canada, "Frequently Asked Questions (FAQs): How are childhood cancers different from adult cancers?" http://www.candlelighters.ca/about/faqs.html.
47 Schwartz, C. L. (1999). "Long-Term Survivors of Childhood Cancer: The Late Effects of Therapy."
The Oncologist. 4(1): 45—54.
48 For a more fulsome discussion of "late effects," see http://www.cancer.org/docroot/CRI/content/CRI_2_6x_Late_Effects_of_Childhood_Cancer.asp?sitearea=C RI&viewmode=print&
49 The external causes of injuries were classified using the International Classification of Disease (ICD), 9th and 10th revisions, according to the recommendations of the International Collaborative Effort on Injury Statistics.
50 Excluding fractures, cause unspecified.
51 Source: Public Health Agency of Canada analysis of the Canadian Institute for Health Information's Hospital Morbidity Database.
52 Source: Canadian Institute for Health Information's Hospital Morbidity Database.
53 Deal, L. W., D. S. Gomby, L. Zippiroli and R. E. Behrman (2000). "Unintentional Injuries in Childhood: Analysis and Recommendations." Unintentional Injuries in Childhood, 10(1): 4—22. Available at: http://www.futureofchildren.org/usr_doc/vol10no1Art1.pdf.
54 Ryan, M. (1987). "A Mother's Perspective." Childhood Drownings: Current Issues and Strategies for Prevention: Conference Proceedings. Brill, D., Micik, S., Yuwiler, J., eds. 23.
55 Miller, T. R., E. O. Romano and R. S. Spicer (2000). "The Cost of Childhood Unintentional Injuries and the Value of Prevention." Unintentional Injuries in Childhood. 10(1): 137—163. Available at: http://www.futureofchildren.org/usr_doc/vol10no1Art6.pdf.