Zhejiang University team interpretation: nearly 1/3 of children infected with Helicobacter pylori, 8 related factors need to pay attention to! The Lancet sub-journal publishes global data

▎Editor of WuXi AppTec content team

Helicobacter pylori (Hp) is a spiral, microanaerobic bacterium that lives in various areas
of the stomach and duodenum.

Hp infection is a common infectious disease that can spread in a "human-to-human" form within a family
.

Children in the family are more susceptible to Hp than adults, which can persist into adulthood and may develop gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma in adulthood
.

Globally, nearly 80% of stomach cancers can be attributed to Hp infection
.

The overall rate of Hp infection in the global adult population is estimated to be about 50%, while global data on Hp infection in children and epidemiological evidence of associated risk factors remain lacking
.

Clarifying the incidence of Hp infection in children and exploring the relevant factors of infection is helpful to understand the current situation and transmission mode of Hp infection in children's groups, and provides an important reference
for relevant departments to formulate prevention strategies.

Image source: 123RF

A study published in The Lancet Child & Adolescent Health discusses
the global HIV infection in children over the past 30 years.

The results showed that Hp infection was very common in children and adolescents worldwide, with an overall infection rate of up to 32.
3%.

According to the paper, the study is "the most comprehensive, systematic and up-to-date assessment of Hp infection in children and adolescents aged 18 years and younger worldwide in 30 years, and for the first time extensively explores the factors associated with Hp infection in children and their effects"
.

The study was first authored by researcher Yuan Changzheng of the School of Public Health of Zhejiang University, and researcher Peige Song as the corresponding author
.

WuXi AppTec's content team invited Researchers Yuan Changzheng and Song Peige to interpret the research results
.

Interpretation of researchers Yuan Changzheng & Song Peige of Zhejiang University

Question 1: What are the innovations and new findings of the global Hp infection rate and related factors in children compared to previous studies?
Researcher Yuan Changzheng & Song Peige: Compared with previous studies, this study included more data and covered a larger sample size, which more comprehensively and systematically assessed the global infection of Hp in children in the past 30 years, and quantitatively estimated
the relevant factors and effects of Hp infection in children.

In addition, the rate of Hp infection among children in China is still high, and China's geographical scope, medical and health level is uneven, and the population structure is very different, and it is also necessary to improve the public's understanding of the harm of Hp infection in children, and continuously strengthen and expand the level and scope of medical and health construction to better prevent Hp infection in Chinese children and reduce the burden of
disease.

Question 3: What other directions are there for further exploration regarding Hp infection in children? Based on this research result, what research work does your team plan to carry out in the future?
Researchers Yuan Changzheng & Song Peige: Our team will focus on China in the future to explore the epidemiological heterogeneity and sources of differences (such as age, regional differences, etc.

Screenshot credit: The Lancet Child & Adolescent Health

In this study, the team searched for population-based observational studies published between the inception of the database and October 25, 2021 in mainstream foreign language literature databases (PubMed, Embase, MEDLINE, and Scopus), and finally included 198 articles (all cross-sectional studies) reporting Hp infection rates in children aged 18 years and younger, covering a total of 632 data points and 152,650 children
.

Overview of Hp infection rates in children

The research team used a multi-level mixed-effects metaregression analysis to estimate the global rate of Hp infection in children, and the results showed that:

The global overall infection rate of Hp in children was 32.
3% (95% CI = 27.
3-37.
8).


Over the past 30 years, the rate of Hp infection among children has fallen by more than half, from 42.
2% before 2000 to 19.
3%
in 2010 and beyond.

In addition, the global rate of Hp infection in children varied by diagnostic testing (serological testing 28.
6% vs urea breath test or fecal antigen test 35.
9%)
.

Globally, in terms of demographic characteristics such as gender and age,

• There was no significant difference in the incidence of Hp infection in children by sex
  .
  
  Among them, the Hp infection rate was 32.
  7% for boys and 32.
  2%
  for girls.
  
  
  

• Regardless of the diagnostic tests, infection rates are significantly higher in older children than in younger children
  .
  
  Among them, the Hp infection rate of children aged 6 years and below was 26.
  0%, the Hp infection rate of children aged 7-12 years was 33.
  9%, and the infection rate of children aged 13-18 years was 41.
  6%.
  
  
  
  

Globally, from the perspective of different regions and environmental factors,

• The rate of Hp infection among children is significantly higher in rural areas than in urban areas
  .
  
  Among them, the infection rate in rural areas was 48.
  6% and in urban areas was 23.
  7%.
  
  
  

• The rate of Hp infection obtained based on different examination institutions is different
  .
  
  Compared with tests based on community (37.
  3%) or school (31.
  9%), tests taken in physical examinations in health care institutions (21.
  7%) had significantly lower
  rates of Hp infection in children.
  
  

• Geographically, Hp infection rates in children are highest in Africa (44.
  1%) and lowest in the Western Pacific (20.
  0%)
  .
  
  

• Rates of Hp infection in children reported vary widely from country to country, with rates as low as 2.
  0% and 3.
  5% in Finland and Iceland, respectively, and over 70.
  0%
  in Benin and Peru.
  
  The infection rate among children in China is 26.
  8% (from data from 20,761 children in 17 studies
  ).
  
  

• Notably, the Hp infection rate (43.
  2%) among children in low- and middle-income countries is almost double
  the rate of child infection in high-income countries (21.
  7%).
  
  

Factors associated with Hp infection in children

The research team divided the 26 factors associated with Hp infection into 5 categories (covering family, community, and individual characteristics), and the comprehensive analysis found that whether or not they were stratified by diagnostic tests (serology, urea breath test, or fecal antigen test), higher rates of Hp infection in children were always strongly correlated with the following factors:

• Sibling infection with Hp (odds ratio, OR] = 3.
  33, 95% CI = 1.
  53–7.
  26, i.
  e.
  , the ratio of Hp infection in siblings infected with Hp, 2.
  33 times higher than that of children without siblings infected with Hp);

• Mother infected with Hp (OR=3.
  31, 95% CI=2.
  21–4.
  98);

• shared rooms for family members (OR=1.
  89, 95% CI=1.
  49–2.
  40);

• The number of children in the family is higher (OR=1.
  84, 95% CI=1.
  44–2.
  36);

• Low household economic level (OR=1.
  63, 95% CI=1.
  46–1.
  82);

• lack of sewage treatment systems (OR=1.
  60, 95% CI=1.
  22–2.
  10);

• Drinking unboiled or untreated water (OR=1.
  52, 95% CI=1.
  32–1.
  76);

• Age (OR=1.
  27 per 1 year of age, 95% CI = 1.
  15–1.
  40).
  
  
  

Image source: 123RF

Indications for Hp testing and diagnosis of infection in children

At present, the "Expert Consensus on the Diagnosis and Treatment of Helicobacter pylori Infection in Children" gives specific suggestions for the detection and indication of Hp in children:

1) Peptic ulcer
.

2) Gastric mucosa-related lymphoid tissue lymphoma
.

3) Chronic gastritis
.

4) Children
with stomach cancer in first-degree relatives.

5) Unexplained refractory iron deficiency anemia
.

6) Plan to take nonsteroidal anti-inflammatory drugs (including low-dose aspirin)
for a long time.

7) Routine testing is not recommended: There is currently insufficient evidence to suggest that Hp infection is associated
with otitis media, periodontal disease, food allergies, idiopathic thrombocytopenic purpura and growth retardation.

The purpose of clinical examination is to look for the underlying cause, not to detect the presence of Hp infection
.

Therefore, Hp testing
is not recommended in children with functional abdominal pain.

Infection with Hp syndrome can be judged to be in one of the following four categories:

1) Positive bacterial culture;

2) Both histopathological examination and rapid urease test (RUT) are positive;

3) If the histopathological examination and RUT results are inconsistent, further non-invasive tests such as urea breath test (UBT) or fecal Hp antigen test (SAT) are required;

4) When peptic ulcer bleeds, either pathological histology or RUT is positive
.

Expert introduction

Dr.
Yuan Changzheng, Researcher

Researcher of the 100 Talents Program of the School of Public Health, Zhejiang University, doctoral supervisor

Adjunct Assistant Professor at Harvard University's Chen Zengxi School of Public Health

Research Areas: Nutritional Epidemiological Methodology, Nutrition and Cognitive Health

Education: B.
S.
in Preventive Medicine, School of Public Health, Peking University, M.
S.
in Epidemiology and Ph.
D.
in Nutritional Epidemiology, Chen Zengxi School of Public Health, Harvard University

Want to join Yuan Changzheng Research Group? Click here for details: The Yuan Changzheng Research Group of Zhejiang University School of Public Health is recruiting postdoctoral and research assistants

Dr.
Peige Song is a researcher at the 100 Talents Program at the School of Public Health, Zhejiang University, and an honorary researcher at the University of Edinburgh, assistant director of the Center for Global Health, Zhejiang University School of Medicine

Research Interests: Global Health, Maternal and Child Health

Education: Bachelor of Nursing, School of Nursing, Peking University, Master of Science in Child and Adolescent Health and Maternal and Child Health at Peking University School of Public Health, Master of Population Health from the University of Edinburgh School of Medicine, PhD in Global Health, Centre for Global Health, University of Edinburgh