Are Males in Trouble From the Start?
Men are known to have higher mortality rates than women, an observation that appears to apply to male infants, children, and adolescents, too.
Pediatricians have long known that adolescent males have a significantly higher rate of death due to suicides, homicides, and accidents. Interestingly, U.S. males appear to have a higher mortality rate throughout their entire lifespan, from birth through early childhood and adolescence and into adulthood, than do their female counterparts.
A recently published study1 investigated the increased male-to-female mortality rates over a 10-year period as they correlate with age ranges and disease categories in the pediatric population. The authors used 3 primary mortality data sources from the Centers for Disease Control and Prevention: the Wide-Ranging Online Data for Epidemiologic Research (WONDER) system, the National Center for Health Statistics, and the National Program of Cancer Registries. The study also looked at the likelihood of developing a life-threatening disease and the risk of dying from it as it relates to gender in infants, children, adolescents, and young adults.
Causes of death were categorized based on the International Classification of Diseases, 10th Revision (ICD-10) and focused on subjects younger than 20 years of age whose death certificates identified a single underlying cause of death. Conditions unrelated to males, such as those occurring during pregnancy, were excluded. Analysis of the process of acquiring and dying from cancer focused on 7 cancer categories that accounted for 89% of cancer deaths in children under 20 years of age. Stratified relative risk ratios were used to measure the risk of death for male children compared with the risk of death for female children.
Mortality rate data from 1999 to 2008 revealed that the number of male deaths exceeded the number of female deaths across all pediatric age categories. Males had a higher mortality rate than did females in most of the ICD-10’s major disease categories. The 2 exceptions were conditions involving the musculoskeletal system and connective tissue, and diseases of skin and subcutaneous tissue, both of which were attributed to systemic or discoid lupus. Even in the age group of 15 to 19 years, when external causes of morbidity and mortality such as accidental and nonaccidental trauma were excluded, males continued to demonstrate an increased relative risk of death.
The authors used cancer as the disease model to investigate whether increased mortality in males could be attributed to their having a greater likelihood of developing a disease that subsequently became the cause of mortality, or whether males had an increased risk of dying once diagnosed with the disease. Males under 20 years had an overall increased risk of incidence of the 7 leading cancer types in the pediatric population, as well an increased fatality rate compared with age-matched females. This combination of greater incidence risk and greater mortality proportion resulted in a greater overall population-level risk for all 7 cancers.
The study relied on the accuracy of ICD-10 coding for the underlying cause of death, which is prone to error.2 Also, data about the impact of social, cultural, or economic factors on mortality were not available or analyzed in this study.
Still, the study supports the idea that males have a higher mortality rate, even among the pediatric population, which is attributable to a higher rate of acquiring various diseases and injuries and dying from them. This suggests “the existence of either a female robustness factor or a male vulnerability factor.” This finding not only is important to the development of disease screening and treatment, but also highlights that we have much to learn about genetics and its role in health, disease, and mortality.
References:
1.Balsara SL, Faerber JA, Spinner NB, Feudtner C. Pediatric mortality in males versus females in the United States, 1999–2008. Pediatrics. 2013; 132(4):631-638.
2.O’Malley KJ, Cook KF, Price MD, Wildes KR, Hurdle JF, Ashton CM. Measuring diagnoses: ICD code accuracy. Health Serv Res. 2005;40(5 pt 2):1620-1639.
Dr Jones is a pediatrician at Nemours/Alfred I. duPont Hospital for Children in Wilmington, Delaware.
Charles A. Pohl, MD––Series Editor:Dr Pohl is professor of pediatrics and senior associate dean of student affairs and career counseling at Jefferson College in Philadelphia, Pennsylvania.