Social determinants and risk factors for tuberculosis; need for harmonisation of definitions in the EU/EEA? Vahur Hollo, poster at ESCAIDE 2016

1. Background
• In most countries of the European Union (EU) and European Economic Area (EEA), tuberculosis (TB) rates are declining. However, this
trend is not uniform and may mask high TB rates in a subpopulation associated with a specific socioeconomic status and risk factor.
• In 2014, the Wolfheze Working Group conducted a survey among all 53 countries of the WHO European Region to investigate which social
determinants and risk factors for TB are collected in national TB surveillance systems.
• ECDC conducted a follow-up study in the EU/EEA Member States (MS).
Conclusions
EU/EEA Member States collect data on a large number of different social determinants and risk factors for TB and use different definitions, data
collection methods, diverse categories and data sources. Improving comparability of data on social determinants and risk factors by harmonizing
definitions, categories and data collection methods would allow for better inter-country comparisons.
tuberculosis@ecdc.europa.eu
www.ecdc.europa.eu
Methods
• A semi-structured questionnaire was sent to TB surveillance
contact points of 31 EU/EEA Member States by ECDC in
September 2015.
• The answers were grouped by concepts and evaluated using
descriptive analysis.
Social determinants and risk factors for tuberculosis;
need for harmonisation of definitions in the EU/EEA?
Vahur Hollo, Brigita Molnarova, Marieke J. van der Werf
European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
Table 1. TB social determinant concepts collected in more
than 50% of countries responding to the survey in EU/EEA,
2015
Results
Figure. Responders to the Social Determinants
questionnaire, EU/EEA, 2015
Objective
• To document the definitions of social determinants and risk factors
of TB as used by the national surveillance systems to be able to
provide options for interventions for tuberculosis prevention and
control in hard to reach and vulnerable populations in the EU/EEA.
Collected
(N of countries)
% of countries
collecting
Origin* 27 100%
Place of birth* 26 96%
Current imprisonment* 21 78%
Citizenship (nationality)* 17 63%
Homelessness 17 63%
Employment status 16 59%
Years since entering
reporting country
15 56%
Urban/rural residence 14 52%
Table 2. TB risk factor concepts collected in more than 50%
of countries responding to the survey in EU/EEA, 2015
Collected
(N of countries)
% of countries
collecting
Contact with TB case 22 81%
HIV infection* 20 74%
Diabetes mellitus 15 56%
Use of alcohol 14 52%
Use of illicit drugs 14 52%
Twenty-seven (87%) of 31 countries responded to the survey. In
addition to social determinants already collected at European level, 21
different social determinants were collected by at least one country.
This is in addition to social determinants collected already at European
level (origin, imprisonment). More than half of the countries collects
data on homelessness, employment status, living in urban/rural
settings (Table 1).
Responded
No response
Information regarding potential risk factors for TB, such as known TB
contacts, diabetes, use of alcohol and illicit drugs are collected also by
more than half of responders (Table 2). Similar or greater variations
apply to the collection of risk factors for TB.
For example, information on alcohol consumption is collected by 14
countries. However it is defined in multiple ways and collected among
others as alcohol dependency, alcohol use or misuse, treating doctor’s
assessment of the patient’s ability to adhere to treatment, etc. This is
measured by a variety of ways, such as by using ICD code, according
to national standards, Cage score, judgement of the attending
physician, WHO proposed definitions, etc.
* Already included to the joint ECDC/WHO TB data collection system,
usually well defined
Countries collect data on the same social determinants from a variety
of data sources (e.g. national vital registries, notification forms for
homelessness and ethnicity) or by using different definitions and/or
categories with varied levels of detail.
For example, information on employment is collected by 16 (59%)
countries, but most of them record employment differently. Some
countries record only current status of employment (categories:
employed, unemployed, unknown), while others use broader codes of
occupation or type of activity (categories: unemployed, employed,
disabled, retired, working irregularly, student, other/free text).
Moreover, data are further complicated by the fact that employment
data are also collected according to different age groups in some
countries responding to the survey (e.g. employment information is
collected for ages 15 – 70 years or for all TB cases).
Seven Member States reported merging social case categories on the
TB notification form, e.g. refugees/asylum seekers/undocumented
migrants, which does not allow to determine the specific risk group.
Free text options used, or only ticking a box with risk factor name
does make comparability more difficult; (e.g. if only “Yes” is collected,
are the missing data considered as “No”, or “Unknown”).