APPLICATION OF BIOSTATISTICS IN RISK ASSESSMENT - the CESAR study

This is presented on Conference "Remediation of Hazardous Wastes: Technology and Health Effects", Prague, 16-19.11.1997

CESAR is acronym of "Central European Study of Air Pollution and Respiratory Health"

Статията на Български

BACKGROUND

The data obtained from routine health statistics during the last years show an increased rate of respiratory diseases among children.
Together with that, monitoring of environmental pollution evidences elevated concentrations in the ambient air of our country.
There is no evidence for effect of PM10 on the respiratory system.
The information about the role of socio-economic factors for children’s health during the last years is insufficient.

OBJECTIVE

Assessment of environmental risk factors for children’s respiratory health. The results reported concern mostly the role of some individual factors.

PROCEDURE AND METHODS

An epidemiological study was carried out in four regions of Bulgaria with different kind and degree of ambient air pollutants. The data were obtained from 3948 children (randomly selected), aged 7 to 11 years, both sexes.

A questionnaire about children’s health and some individual factors, e.g. social status, living conditions, nutrition patterns etc., have been administered. The bronchial asthma, bronchitis and pneumonia have been chosen as indicators of the respiratory health. The variables selected for the individual factors are given in Table1. The logistic regression technique was used to evaluate the effect of these factors on the health risk. 

RESULTS

Results are shown in next table and figures.

Table 1

Name of Variables		N0 of variables
Respondent of questionnaire:		Mother
		father or other relative	1
Education:	mother:	hight
		secondary	2
		primary	3
Occupation:	mother:	manager
		clerical	4
		skilled manual	5
		unskilled manual	6
Employment:	mother:	employed
		entrepreneur	7
		at home	8
		unemployed	9
Birth weight		>=2.5kg.
		<2.5kg.	10
Perinatal complications:		no
		yes	11
Nutrition:	vegetables:	>4 times per week
		2-4 times per week	12
		<4 times per month	13
time spend outdoors:		more than other	14
		like other
		less then other	15
sport:		in school
		additional	16
Day care:	in the first 2 years:	no
		yes	17
Housing conditions:	Household density:	<=1 people per room
		1.1-1.4 people per room	18
		>=1.5 people per room	19
	material of bedroom floor:	smooth surface	20
		carped on a smooth surface	21
	chipboard furniture:	yes
		no	22
	moisture frequency:	never
		sometimes	23
		often	24
		always	25
	moisture:	no
		yes	26
Traffic intensity:		low
		middle	27
		high	28
		very high	29
Smoking:	total number of cigarettes smoking in household, in group by 10:	none
		1-10 per day	30
		11-20 per day	31
		>20 per day	32

fig 1 Bronchial Asthma, Bronchitis and Pneumonia (percentage rates) according to the four areas

fig 2 Odds Ratios and 95% Conf. Intervals of Bronchitis According to some Environmental Factors, Adjusted for Area, Age and Sex

fig 3 Odds Ratios and 95% Conf. Intervals of Asthma According to some Environmental Factors, Adjusted for Area, Age and Sex

fig 4 Odds Ratios and 95% Conf. Intervals of Pneumonia According to some Environmental Factors, Adjusted for Area, Age and Sex

CONCLUSIONS

The incidence rates of bronchial asthma, bronchitis and pneumonia were directly related with the poor housing conditions, and particularly the presence of moisture and mould spots in the homes

The insufficient amount of vegetables in children’s diet also affect significantly their respiratory health

Children, born with perinatal complications or low birth weight are predisposed to bronchial asthma and pneumonia

The decreased physical activity, as indicated by the insufficient sport and games in the open air also contributes to the development of asthma and bronchitis

The prevalence of bronchial asthma is higher with children, residents of the areas with intensive traffic

The exposure to tobacco smoke, when living with parents - smokers, also has an unfavorable effect for the development of bronchial asthma

Parents’ education, occupation and qualification did not affect significantly the children’s respiratory health

ACKNOWLEDGEMENTS

This project is financed by the European Union’s Phare Programme, which provides grant finance to support it's partner countries in Central and Eastern Europe to the stage where they are ready to assume the obligations of European Union membership.