Johan Van der Heyden

Socio-economic differences in participation of households in a Belgian national health survey

BACKGROUND Socio-economic inequalities in health survey participation can jeopardize the extrapolation of the survey findings to the total population. Earlier research, based on aggregated data, showed that in Belgium less-educated people with poor health were less likely to participate in a health survey. In this article, the association by socio-economic status and household non-response in a health survey is examined. METHODS A linkage between the Belgian Health Survey 2001 with Census 2001 enabled us to evaluate the participation by socio-economic status. RESULTS We observed that the socio-economic position was a determinant of health survey participation: participation rate was significantly lower in households with a lower socio-economic profile. CONCLUSION Socio-economic inequalities in participation can introduce a bias in the health survey findings. Strategies targeting improvement of the participation of lower socio-economic groups need to be considered.

Multiple risk behaviour: increasing socio-economic gap over time?

BACKGROUND Unhealthy behaviours often occur in combination. In this study the relationship between education and lifestyle, defined as a cluster of risk behaviours, has been analysed with the purpose to assess socio-economic changes in multiple risk behaviour over time. METHODS Cross-sectional data from the Belgian Health Interview Surveys 1997, 2001 and 2004 were analysed. This study is restricted to persons aged ≥ 15 years with information on those health behaviours and education (n = 7431, n = 8142 and n = 7459, respectively). A lifestyle index was created based on the sum of the four unhealthy behaviours: smokers vs. non-smokers, risky versus non-risky alcohol use, sedentaryness vs. physically active and poor vs. healthy diet. The lifestyle index was dichotomized as low (0-2) vs. high (3-4). For the assessment of socio-economic inequalities in multiple risk behaviour, summary measures as Odds Ratio (OR) and Relative Index of Inequality (RII) were calculated using logistic regression, stratified by sex. RESULTS Of the adult population, 7.5% combined three to four unhealthy behaviours. Lower educated men are the most at risk. Besides, the OR among men significantly increased from 1.6 in 2001 to 3.4 in 2004 (P = 0.029). The increase of the OR among women was less pronounced. The RII, on the other hand, did not show any gradient, neither for men nor for women. CONCLUSION Multiple risk behaviour is more common among lower educated people. An increasing polarization in socio-economic inequalities is assessed from 2001 to 2004 among men. Therefore, health promotion programmes should focus on the lower socio-economic classes and target risk behaviours simultaneously.

Healthcare utilisation among the Belgian elderly in relation to their socio-economic status

OBJECTIVES To analyse the association between healthcare utilisation of elderly persons (65 and over) in Belgium in terms of contacts with GP or specialist and the socio-economic indicators household income, highest educational level within the household, and housing tenure. METHODS A cross-sectional study based on 4494 non-institutionalised elderly participants in the Belgian Health Interview Surveys of 2001 and 2004. Socio-economic gradients in contacts (yes or no) with a GP or specialist were explored, based on the socio-behavioural model of Andersen, a conceptual framework that includes the most important determinants of healthcare utilisation. Three multivariate models were constructed using multiple logistic regression. RESULTS After adjustment for age, sex, health status (self-assessed health, functional restrictions, and comorbidity), region, and living situation, initial differences in contacts with a GP and specialist between the different socio-economic groups disappeared among the elderly. On the other hand, contacts with a specialist remain dependent on SES in the younger population. CONCLUSIONS Adjustment for the determinants of healthcare utilisation among the Belgian elderly nullified the socio-economic gradients in contacts with a GP and specialist that initially existed. The results point to a potential link with the Belgian social and health policy.

Impact of Chronic Conditions and Multimorbidity on the Disability Burden in the Older Population in Belgium

BACKGROUND The increase in longevity along with a high prevalence of chronic conditions contribute to increased disability burden. Despite the high occurrence of multimorbidity observed in advanced ages, most studies are restricted to the investigation of individual diseases. In this study, we assessed the impact of chronic conditions and multimorbidity on the disability burden in the older population in Belgium. METHODS Data from 9,482 participants in the 2001, 2004, or 2008 Belgian Health Interview Surveys aged 55 years or older were analyzed. Disability was defined based on the Global Activity Limitation Indicator (GALI). To attribute disability to single chronic conditions and disease pairs, a multiple additive hazard model was fitted. RESULTS Musculoskeletal conditions (45.3%), chronic respiratory diseases (11.2%), and cardiovascular diseases (10.2%) diseases were the most frequent conditions. Cardiovascular diseases, the co-occurrence of chronic respiratory diseases and depression, neurological diseases, cancer, and the combination of diabetes and cardiovascular diseases were the top five disabling conditions. The disability prevalence in the older population in Belgium was 35.6% (confidence interval =35.0; 36.2%). The most important contributors to the disability burden were musculoskeletal, cardiovascular, and chronic respiratory diseases. CONCLUSIONS The present findings provide a deeper understanding of the role of chronic conditions and multimorbidity on the disability burden in the older population in Belgium. Although the disease pairs showed a low contribution to the disability burden, their occurrence presented a high impact on disability. Prevention strategies to tackle disability should target the main contributors to the disability burden and the most disabling conditions/disease pairs, especially in the clinical practice.

Using multiple measures of inequalities to study the time trends in social inequalities in smoking

BACKGROUND The time trends in social inequalities in smoking have been examined in a number of international publications; however, these studies have rarely used multiple measures of health inequalities simultaneously. Also the analytical approach used often did not account, as recommended, for the changes in the relative distribution of social groups and the changes in the absolute level of the health outcome within social groups. METHODS Data from four successive waves of the Belgian Health Interview Survey (1997, 2001, 2004, 2008) were used to study the time trends in educational inequalities in daily smoking for those aged between 15 and 74 years. We estimated two measures of relative inequalities: the OR and the relative index of inequality; and two measures of absolute inequalities: the population attributable fraction and the slope index of inequality. Three of these measures (relative index of inequality, population attributable fraction, slope index of inequality) account for the change in the relative size of the social groups over time. RESULTS The four measures of inequality were consistent in showing significant inequalities among educational groups. The time trends, however, were less consistent. Measures of trends in relative inequalities witnessed a small linear increase. However, no substantial over time change was observed with the measures of absolute inequalities. CONCLUSION The time trends in social inequalities in smoking varied according to the measure of inequality used. This study confirms the importance of using multiple measures of inequalities to understand and monitor social inequalities in smoking.

Impact of Genetic Notification on Smoking Cessation: Systematic Review and Pooled-Analysis

Objectives This study aimed to evaluate the impact of genetic notification of smoking-related disease risk on smoking cessation in the general population. Secondary objectives were to assess the impact of genetic notification on intention-to-quit smoking and on emotional outcomes as well as the understanding and the recall of this notification. Methods A systematic review of articles from inception to August 2011 without language restriction was realized using PubMed, Embase, Scopus, Web of Science, PsycINFO and Toxnet. Other publications were identified using hand search. The pooled-analysis included only randomized trials. Comparison groups were (i) high and low genetic risk versus control, and (ii) high versus low genetic risk. For the pooled-analysis random effect models were applied and sensitivity analyses were conducted. Results Eight papers from seven different studies met the inclusion criteria of the review. High genetic risk notification was associated with short-term increased depression and anxiety. Four randomized studies were included in the pooled-analysis, which revealed a significant impact of genetic notification on smoking cessation in comparison to controls (clinical risk notification or no intervention) in short term follow-up less than 6 months (RR = 1.55, 95% CI 1.09–2.21). Conclusions In short term follow-up, genetic notification increased smoking cessation in comparison to control interventions. However, there is no evidence of long term effect (up to 12 month) on smoking cessation. Further research is needed to assess more in depth how genetic notification of smoking-related disease could contribute to smoking cessation.

Is the different time trend (1997-2008) of the obesity prevalence among adults in the three Belgian regions associated with lifestyle changes?

BackgroundObesity is a major public health issue with increasing prevalence among adults. However, in Belgium the regional time trends (1997–2008) differed: the prevalence of obesity increased in the Flemish and Brussels Regions, but remained stable in the Walloon Region, the latter still showing the highest prevalence. The purpose of the present study is to explore if the different time trends of obesity prevalence in the three Belgian regions is associated with lifestyle changes.MethodsWe used data from four successive cross-sectional waves (1997, 2001, 2004 and 2008) of the Belgian Health Interview Survey. The study was restricted to the adult population, resulting in samples of respectively 8,071, 9,391, 10,319 and 8,831 individuals. In line with the WHO definition, obesity was defined as having a BMI ≥ 30. Differences in regional trends of obesity were investigated through stratified analyses. The association between obesity and survey year, adjusted for lifestyle factors (alcohol consumption, smoking, fruit and vegetables consumption and leisure time physical activity), was assessed via logistic regression models. Interactions were added to the models to explore if the association between lifestyle factors and obesity varied over time.ResultsObesity was associated with daily alcohol use in the Brussels (OR 0.66, 95% CI 0.50-0.88) and Walloon Regions (OR 0.8, 95% CI 0.6-0.9), with lower tendencies of being obese for daily drinkers. The probability of being obese was lower among smokers in the Flemish (OR 0.7, 95% CI 0.6-0.8) and Walloon Regions (OR 0.7, 95% CI 0.6-0.9) than among non-smokers. A lack of leisure time physical activity was associated with the probability of being obese in all regions (Brussels Region: OR 1.6, 95% CI 1.3-1.8; Flemish Region: OR 1.6, 95% CI 1.4-1.9; Walloon Region: OR 1.8, 95% CT 1.6-2.1). This association decreased significantly between 1997 and 2008 only in the Walloon Region.ConclusionThe decreasing association between obesity and a lack of leisure time physical activity in the Walloon Region between 1997 and 2008 could indicate that there is an increasing awareness of risk factors for obesity in the Walloon population, which may have resulted in a more favourable evolution of the obesity epidemic.

Preventive care use among the Belgian elderly population: does socio-economic status matter?

Objective: To analyze the association between influenza and pneumococcus vaccination and blood cholesterol and blood sugar measurement by Belgian elderly respondents (≥65 years) and socio-demographic characteristics, risk factors, health status and socio-economic status (SES). Methods: A cross-sectional study based on 4,544 non-institutionalized elderly participants of the Belgian Health Interview Surveys 2004 and 2008. Multivariate logistic regression models were constructed to examine the independent effect of socio-demographic characteristics, risk factors, health status and SES on the four preventive services. Results: After adjustment for age, sex, region, survey year, living situation, risk factors (body mass index, smoking status, physical activity) and health status (self-assessed health and longstanding illness) lower educated elderly were significantly less likely to report a blood cholesterol and blood sugar measurement. For instance, elderly participants with no degree or only primary education were less likely to have had a cholesterol and blood sugar measurement compared with those with higher education. Pneumococcus vaccination was not related to educational level, but lower income groups were more likely to have had a pneumococcus immunization. Influenza vaccination was not significantly related to SES. Conclusion: The results highlight the need to promote cholesterol and blood sugar measurement for lower SE groups, and pneumococcus immunization for the entire elderly population. Influenza immunization seems to be equally spread among different SE groups.

Public health in the genomic era: will Public Health Genomics contribute to major changes in the prevention of common diseases?

The completion of the Human Genome Project triggered a whole new field of genomic research which is likely to lead to new opportunities for the promotion of population health. As a result, the distinction between genetic and environmental diseases has faded. Presently, genomics and knowledge deriving from systems biology, epigenomics, integrative genomics or genome-environmental interactions give a better insight on the pathophysiology of common diseases. However, it is barely used in the prevention and management of diseases. Together with the boost in the amount of genetic association studies, this demands for appropriate public health actions. The field of Public Health Genomics analyses how genome-based knowledge and technologies can responsibly and effectively be integrated into health services and public policy for the benefit of population health. Environmental exposures interact with the genome to produce health information which may help explain inter-individual differences in health, or disease risk. However today, prospects for concrete applications remain distant. In addition, this information has not been translated into health practice yet. Therefore, evidence-based recommendations are few. The lack of population-based research hampers the evaluation of the impact of genomic applications. Public Health Genomics also evaluates the benefits and risks on a larger scale, including normative, legal, economic and social issues. These new developments are likely to affect all domains of public health and require rethinking the role of genomics in every condition of public health interest. This article aims at providing an introduction to the field of and the ideas behind Public Health Genomics.

Activity limitations predict health care expenditures in the general population in Belgium

BackgroundDisability and chronic conditions both have an impact on health expenditures and although they are conceptually related, they present different dimensions of ill-health. Recent concepts of disability combine a biological understanding of impairment with the social dimension of activity limitation and resulted in the development of the Global Activity Limitation Indicator (GALI). This paper reports on the predictive value of the GALI on health care expenditures in relation to the presence of chronic conditions.MethodsData from the Belgian Health Interview Survey 2008 were linked with data from the compulsory national health insurance (n = 7,286). The effect of activity limitation on health care expenditures was assessed via cost ratios from multivariate linear regression models. To study the factors contributing to the difference in health expenditure between persons with and without activity limitations, the Blinder-Oaxaca decomposition method was used.ResultsActivity limitations are a strong determinant of health care expenditures. People with severe activity limitations (5.1%) accounted for 16.9% of the total health expenditure, whereas those without activity limitations (79.0%), were responsible for 51.5% of the total health expenditure. These observed differences in health care expenditures can to some extent be explained by chronic conditions, but activity limitations also contribute substantially to higher health care expenditures in the absence of chronic conditions (cost ratio 2.46; 95% CI 1.74-3.48 for moderate and 4.45; 95% CI 2.47-8.02 for severe activity limitations). The association between activity limitation and health care expenditures is stronger for reimbursed health care costs than for out-of-pocket payments.ConclusionIn the absence of chronic conditions, activity limitations appear to be an important determinant of health care expenditures. To make projections on health care expenditures, routine data on activity limitations are essential and complementary to data on chronic conditions.