Does health literacy mediate the relationship between socioeconomic status and health related outcomes in the Belgian adult population?

BACKGROUND: Health literacy (HL) has been put forward as a potential mediator through which socioeconomic status (SES) affects health. This study explores whether HL mediates the relation between SES and a selection of health or health-related outcomes. METHODS: Data from the participants of the Belgian health interview survey 2018 aged 18 years or older were individually linked with data from the Belgian compulsory health insurance (n = 8080). HL was assessed with the HLS-EU-Q6. Mediation analyses were performed with health behaviour (physical activity, diet, alcohol and tobacco consumption), health status (perceived health status, mental health status), use of medicine (purchase of antibiotics), and use of preventive care (preventive dental care, influenza vaccination, breast cancer screening) as dependent outcome variables, educational attainment and income as independent variables of interest, age and sex as potential confounders and HL as mediating variable. RESULTS: The study showed that unhealthy behaviours (except alcohol consumption), poorer health status, higher use of medicine and lower use of preventive care (except flu vaccination) were associated with low SES (i.e., low education and low income) and with insufficient HL. HL partially mediated the relationship between education and health behaviour, perceived health status and mental health status, accounting for 3.8-16.0% of the total effect. HL also constituted a pathway by which income influences health behaviour, perceived health status, mental health status and preventive dental care, with the mediation effects accounting for 2.1-10.8% of the total effect. CONCLUSIONS: Although the influence of HL in the pathway is limited, our findings suggest that strategies for improving various health-related outcomes among low SES groups should include initiatives to enhance HL in these population groups. Further research is needed to confirm our results and to better explore the mediating effects of HL.

Association between SARS-CoV-2 variants and post COVID-19 condition: findings from a longitudinal cohort study in the Belgian adult population.

BACKGROUND: While many studies on the determinants of post-COVID-19 conditions (PCC) have been conducted, little is known about the relationship between SARS-CoV-2 variants and PCC. This study aimed to assess the association between different SARS-CoV-2 variants and the probability of having PCC three months after the infection. METHODS: This study was a longitudinal cohort study conducted between April 2021 and September 2022 in Belgium. In total, 8,238 adults with a confirmed SARS-CoV-2 infection were followed up between the time of their infection and three months later. The primary outcomes were the PCC status three months post infection and seven PCC symptoms categories (neurocognitive, autonomic, gastrointestinal, respiratory, musculoskeletal, anosmia and/or dysgeusia, and other manifestations). The main exposure variable was the type of SARS-CoV-2 variants (i.e. Alpha, Delta, and Omicron), extracted from national surveillance data. The association between the different SARS-CoV-2 variants and PCC as well as PCC symptoms categories was assessed using multivariable logistic regression. RESULTS: The proportion of PCC among participants infected during the Alpha, Delta, and Omicron-dominant periods was significantly different and respectively 50%, 50%, and 37%. Participants infected during the Alpha- and Delta-dominant periods had a significantly higher odds of having PCC than those infected during the Omicron-dominant period (OR = 1.61, 95% confidence interval [CI] = 1.33-1.96 and OR = 1.73, 95%CI = 1.54-1.93, respectively). Participants infected during the Alpha and Delta-dominant periods were more likely to report neurocognitive, respiratory, and anosmia/dysgeusia symptoms of PCC. CONCLUSIONS: People infected during the Alpha- and Delta-dominant periods had a higher probability of having PCC three months after infection than those infected during the Omicron-dominant period. The lower probability of PCC with the Omicron variant must also be interpreted in absolute figures. Indeed, the number of infections with the Omicron variant being higher than with the Alpha and Delta variants, it is possible that the overall prevalence of PCC in the population increases, even if the probability of having a PCC decreases.

Linking health survey data with health insurance data: methodology, challenges, opportunities and recommendations for public health research. An experience from the HISlink project in Belgium.

In recent years, the linkage of survey data to health administrative data has increased. This offers new opportunities for research into the use of health services and public health. Building on the HISlink use case, the linkage of Belgian Health Interview Survey (BHIS) data and Belgian Compulsory Health Insurance (BCHI) data, this paper provides an overview of the practical implementation of linking data, the outcomes in terms of a linked dataset and of the studies conducted as well as the lessons learned and recommendations for future links.Individual BHIS 2013 and 2018 data was linked to BCHI data using the national register number. The overall linkage rate was 92.3% and 94.2% for HISlink 2013 and HISlink 2018, respectively. Linked BHIS-BCHI data were used in validation studies (e.g. self-reported breast cancer screening; chronic diseases, polypharmacy), in policy-driven research (e.g., mediation effect of health literacy in the relationship between socioeconomic status and health related outcomes, and in longitudinal study (e.g. identifying predictors of nursing home admission among older BHIS participants). The linkage of both data sources combines their strengths but does not overcome all weaknesses.The availability of a national register number was an asset for HISlink. Policy-makers and researchers must take initiatives to find a better balance between the right to privacy of respondents and society's right to evidence-based information to improve health. Researchers should be aware that the procedures necessary to implement a link may have an impact on the timeliness of their research. Although some aspects of HISlink are specific to the Belgian context, we believe that some lessons learned are useful in an international context, especially for other European Union member states that collect similar data.

Classification of post COVID-19 condition symptoms: a longitudinal study in the Belgian population.

OBJECTIVES: Since the onset of the COVID-19 pandemic, most research has focused on its acute pathophysiology, yet some people tend to experience persisting symptoms beyond the acute phase of infection, referred to as post COVID-19 condition (PCC). However, evidence on PCC is still scarce. This study aimed to assess the distribution, classification of symptoms and associated factors of PCC in adults. DESIGN: Longitudinal online cohort study. SETTING: National study in Belgium. PARTICIPANTS: Participants were Belgian adults with a recent SARS-CoV-2 infection and were recruited when called up for contact tracing. A total of 3039 participants were included and completed an online questionnaire at the time of their infection and again 3 months later. OUTCOME MEASURES: The baseline questionnaire assessed the initial health status of the participants and their status during the acute phase of the infection. The follow-up questionnaire assessed their PCC status 3 months after infection. A latent class analysis (LCA) was performed to assess whether there are different classes of individuals with a similar set of self-reported PCC symptoms. RESULTS: Half of the participants reported PCC 3 months after infection (47%). The most frequent symptoms were fatigue (21%), headache (11%) and memory problems (10%). The LCA highlighted three different classes of PCC symptoms with different risk factors: (1) a combination of loss of smell and taste, (2) a combination of neurological symptoms and (3) other heterogeneous symptoms. CONCLUSIONS: With the increasing number of people who underwent COVID-19, PCC has become an important but complex public health problem due to the heterogeneity of its symptoms. The classification of symptoms performed in this study can help give insight into different aetiologies of PCC and better plan care according to the symptoms and needs of those affected.

Data collection in pandemic times: the case of the Belgian COVID-19 health surveys.

BACKGROUND: Survey data were needed to assess the mental and social health, health related behaviors and compliance with preventive measures of the population during the COVID-19 pandemic. Yet, the pandemic challenged classical survey methods. Time and budgetary constraints at the beginning of the pandemic led to ad hoc recruitment of participants and easily manageable data collection modes. This paper describes the methodological choices and results in terms of participation for the COVID-19 health surveys conducted in Belgium. METHODS: The COVID-19 health surveys refer to a series of ten non-probability web surveys organized between April 2020 and March 2022. The applied recruitment strategies were diverse including, amongst others, a launch through the website and the social media of the organizing research institute. In addition, the survey links were shared in articles published in the national press and participants were requested to share the surveys in their network. Furthermore, participants were asked consent to be re-contacted for next survey editions using e-mail invitations. RESULTS: These mixed approaches allowed to reach a substantial number of participants per edition ranging from 49339 in survey 1 to 13882 in survey 10. In addition, a longitudinal component was created; a large share of the same individuals were followed up over time; 12599 participants completed at least 5 surveys. There were, however, sex, age, educational level and regional differences in participation. Post-stratification weighting on socio-demographic factors was applied to at least partly take this into account. CONCLUSION: The COVID-19 health surveys allowed rapid data collection after the onset of the pandemic. Data from these non-probability web surveys had their limitations in terms of representativeness due to self-selection but were an important information source as there were few alternatives. Moreover, by following-up the same individuals over time it was possible to study the effect of the different crisis phases on, amongst others, the mental health. It is important to draw lessons from these experiences: initiatives in order to create a survey infrastructure better equipped for future crises are needed.

Post COVID-19 condition and health-related quality of life: a longitudinal cohort study in the Belgian adult population.

BACKGROUND: Since the onset of the COVID-19 pandemic, most research has focused on the acute phase of COVID-19, yet some people experience symptoms beyond, referred to as post COVID-19 conditions (PCC). However, evidence on PCC and its impacts on health-related quality of life (HRQoL) is still scarce. This study aimed to assess the impact of COVID-19 and PCC on HRQoL. METHODS: This is a longitudinal cohort study of the Belgian adult population with recent SARS-CoV-2 infection. In total, 5,727 people were followed up between the time of their infection and three months later. HRQoL was measured with the EQ-5D-5L questionnaire before and during the infection and three months later. Linear mixed regression models were built to assess the longitudinal association between participants' characteristics and the evolution of their HRQoL. RESULTS: This study found a significant decline in HRQoL during the SARS-CoV-2 infection in comparison to the situation before (ß=-9.91, 95%CI=-10.13;-9.85), but no clinically important difference three months after the infection compared to the situation before, except among people reporting PCC (ß=-11.15, 95%CI=-11.72;-10.51). The main symptoms of PCC with a significant negative impact on the different dimensions of HRQoL were fatigue/exhaustion (21%), headache (11%), memory problems (10%), shortness of breath (9%), and joint (7%) or muscle pain (6%). The dimension of HRQoL most negatively affected by several PCC symptoms was pain/discomfort. CONCLUSIONS: With the growing number of people infected with SARS-CoV-2, PCC and its impact on HRQoL are becoming important public health issues. To allow people with PCC to recover and to limit its detrimental impact on HRQoL, it is essential to manage its various heterogeneous symptoms using a multidisciplinary approach.

Changes in quality-adjusted life expectancy in Belgium, 2013 and 2018.

INTRODUCTION: No information is available in Belgium on life expectancy adjusted for health-related quality of life (HRQoL). Quality-adjusted life expectancy (QALE) captures the multidimensionality of health by accounting for losses in mortality and HRQoL linked to physical, mental, and social impairments. The objective of this study is to estimate for Belgium QALE, the changes in QALE between 2013 and 2018 and the contribution of mortality, HRQoL and its dimensions to this trend. METHODS: The Belgian Health Interview Survey (BHIS), a representative sample of the general population, included the EQ-5D-5L instrument in 2013 and 2018. The tool assesses HRQoL comprising five dimensions (mobility, self-care, usual activities, pain/discomfort, anxiety/depression) using a 5-level severity scoring to define a large variety of health states. The Sullivan method was used to compute at different ages QALE by gender using mortality data from the Belgian statistical office and average EQ-5D scores from the BHIS. QALE was calculated for 2013 and 2018, and changes in QALE over time were decomposed into mortality and ill-health effect. RESULTS: In 2018, QALE at age 15 years (QALE15) was 56.3 years for women and 55.8 years for men, a decrease from 2013 by 0.7 year for women and a stagnation for men. In men, the decrease in mortality counterbalanced the decline in HRQoL. The decline in QALE in women is driven by a decrease in mortality rates that is too small to compensate for the substantial decline in HRQoL before the age of 50 years. In women at older ages, improvements in HRQoL are observed. In women, QALE15 is decreasing due to an increase in pain/discomfort, anxiety/depression and problems in usual activities. In men at age 15, the pain/discomfort and anxiety/depression domains contributed to the stagnation. QALE65 increased somewhat, due to an improvement in self-care and mobility for both genders, and usual activities and anxiety/depression in men only. CONCLUSION: The strength of QALE as member of the family of composite indicators, the health expectancies, is the multidimensional structure of the underlying health component, including both ill-health with different health domains as levels of severity. The ability to decompose differences in the health expectancy not only into a mortality and health component but also into the different health dimensions allows to better inform on general population health trends. Next, compared to other health expectancy indicators, QALE is more sensitive to changes at younger ages.

Time trends in the use of field-substitution in the Belgian health interview survey.

BACKGROUND: Matched field-substitution has been applied in the Belgian Health Interview Survey (BHIS) since the first round. During data-collection, non-participating households are replaced by substitute households, if needed up to seven times. In this manuscript, the use of field-substitution in the six rounds of BHIS (1997-2018) is assessed. We investigated to what extent field-substitution contributes to obtaining the requested net-sample size and whether this has evolved throughout the successive BHIS's. METHODS: Harmonized para-data gathered throughout de data-collection phases are used to define the final participation status of all households that could be contacted for participation to the survey. The share of the substituted households was calculated and possible trends in the use of field-substitution throughout the successive surveys was assessed using logistic regression. Finally, it was examined whether the application of field-substitution changed in terms of the position of the participating household in the clusters, using the ESTIMATE statement in the SAS procedure NLMIXED. RESULTS: Overall, four in ten participating households are substitute households. This proportion remains rather similar over the surveys. The probability of participating according to the position of the household within the cluster is evidently much higher in households at the first position of initial selected clusters. Over the survey-years, the share of participating household derived from substitute clusters in the total number of participating households has slightly increased. CONCLUSION: Field-substitution in BHIS plays a very substantial role in obtaining the requested net sample both in size and composition. Field-substitution, as applied in BHIS might inspire scientists to consider it when developing their surveys.

Predictors of nursing home admission in the older population in Belgium: a longitudinal follow-up of health interview survey participants.

BACKGROUND: This study examines predictors of nursing home admission (NHA) in Belgium in order to contribute to a better planning of the future demand for nursing home (NH) services and health care resources. METHODS: Data derived from the Belgian 2013 health interview survey were linked at individual level with health insurance data (2012 tot 2018). Only community dwelling participants, aged ≥65 years at the time of the survey were included in this study (n = 1930). Participants were followed until NHA, death or end of study period, i.e., December 31, 2018. The risk of NHA was calculated using a competing risk analysis. RESULTS: Over the follow-up period (median 5.29 years), 226 individuals were admitted to a NH and 268 died without admission to a NH. The overall cumulative risk of NHA was 1.4, 5.7 and 13.1% at respectively 1 year, 3 years and end of follow-up period. After multivariable adjustment, higher age, low educational attainment, living alone and use of home care services were significantly associated with a higher risk of NHA. A number of need factors (e.g., history of falls, suffering from urinary incontinence, depression or Alzheimer's disease) were also significantly associated with a higher risk of NHA. On the contrary, being female, having multimorbidity and increased contacts with health care providers were significantly associated with a decreased risk of NHA. Perceived health and limitations were both significant determinants of NHA, but perceived health was an effect modifier on limitations and vice versa. CONCLUSIONS: Our findings pinpoint important predictors of NHA in older adults, and offer possibilities of prevention to avoid or delay NHA for this population. Practical implications include prevention of falls, management of urinary incontinence at home and appropriate and timely management of limitations, depression and Alzheimer's disease. Focus should also be on people living alone to provide more timely contacts with health care providers. Further investigation of predictors of NHA should include contextual factors such as the availability of nursing-home beds, hospital beds, physicians and waiting lists for NHA.

The HLS19-COM-P, a New Instrument for Measuring Communicative Health Literacy in Interaction with Physicians: Development and Validation in Nine European Countries.

BACKGROUND: Sufficient communicative health literacy (COM-HL) is important for patients actively participating in dialogue with physicians, expressing their needs and desires for treatment, and asking clarifying questions. There is a lack of instruments combining communication and HL proficiency. Hence, the aim was to establish an instrument with sufficient psychometric properties for measuring COM-HL. METHODS: The HLS19-COM-P instrument was developed based on a conceptual framework integrating HL with central communicative tasks. Data were collected using different data collection modes in nine countries from December 2019 to January 2021 (n = 18,674). Psychometric properties were assessed using Rasch analysis and confirmatory factor analysis. Cronbach's alpha and Person separation index were considered for reliability. RESULTS: The 11-item version (HLS19-COM-P-Q11) and its short version of six items (HLS19-COM-P-Q6) fit sufficiently the unidimensional partial credit Rasch model, obtained acceptable goodness-of-fit indices and high reliability. Two items tend to under-discriminate. Few items displayed differential item functioning (DIF) across person factors, and there was no consistent pattern in DIF across countries. All items had ordered response categories. CONCLUSIONS: The HLS19-COM-P instrument was well accepted in nine countries, in different data collection modes, and could be used to measure COM-HL.

QALY losses for chronic diseases and its social distribution in the general population: results from the Belgian Health Interview Survey.

BACKGROUND: The burden of chronic diseases is rapidly rising, both in terms of morbidity and mortality. This burden is disproportionally carried by socially disadvantaged population subgroups. Quality-adjusted life years (QALYs) measure the impact of disease on mortality and morbidity into a single index. This study aims to estimate the burden of chronic diseases in terms of QALY losses and to model its social distribution for the general population. METHODS: The Belgian Health Interview Survey 2013 and 2018 provided data on self-reported chronic conditions for a nationally representative sample. The annual QALY loss per 100,000 individuals was calculated for each condition, incorporating disease prevalence and health-related quality of life (HRQoL) data (EQ-5D-5L). Socioeconomic inequalities, based on respondents' socioeconomic status (SES), were assessed by estimating population attributable fractions (PAF). RESULTS: For both years, the largest QALY losses were observed in dorsopathies, arthropathies, hypertension/high cholesterol, and genitourinary problems. QALY losses were larger in women and in older individuals. Individuals with high SES had consistently lower QALY loss when facing a chronic disease compared to those with low SES. In both years, a higher PAF was found in individuals with hip fracture and stroke. In 2013, the health inequality gap amounts to 33,731 QALYs and further expanded to 42,273 QALYs in 2018. CONCLUSION: Given that chronic diseases will rise in the next decades, addressing its burden is necessary, particularly among the most vulnerable (i.e. older persons, women, low SES). Interventions in these target groups should get priority in order to reduce the burden of chronic diseases.

Post COVID-19 condition and its physical, mental and social implications: protocol of a 2-year longitudinal cohort study in the Belgian adult population.

BACKGROUND: Since the onset of the COVID-19 pandemic, most research has focused on the pathophysiology and management of the acute symptoms of COVID-19, yet some people tend to experience symptoms beyond the acute phase of infection, that is, Post COVID-19 condition (PCC). However, evidence on the long-term health impacts of a COVID-19 infection are still scarce. The purpose of this paper is to describe the COVIMPACT study, which aims to set up a cohort of people who have been tested positive for COVID-19 and study the evolution of their physical, mental and social health over the medium (3 months) and long term (two years), and the factors associated with an (un)favorable evolution. METHODS: COVIMPACT is a longitudinal cohort study organised over a two-years period between April 2021 and April 2023. The eligible population is all people aged 18 years and older, living in Belgium, with a recent COVID-19 infection and contacted by the health authorities for contact tracing. Two questionnaires are used: a baseline questionnaire that aims to assess the initial health status of the participants and their status during the acute phase of the illness, and a follow-up questionnaire that is sent every three months after participants enter into the cohort. A matched non-COVID-19 control group was also selected. As of November 1, 2021, 10,708 people completed the baseline questionnaire (5% of the eligible population) and the follow-up participation rate was 79%. In total, 48% of the cohort participants appeared to fit the proposed case definition of PCC (i.e. report at least one symptom related to their COVID-19 infection three months afterwards). DISCUSSION: This study was designed to provide timely information on the short and long term impact of a COVID-19 infection, to stakeholders such as policymakers, health practitioners and people with PCC. Although the follow-up participation rate was good (79%), the participation rate of the eligible population was low (5%). Compared to other studies, this study has a large sample, of non-hospitalised and hospitalised people, who will be followed over a long period of 3 months to two years post infection, and with a global approach to their health.

Anxiety and Depression in Belgium during the First 15 Months of the COVID-19 Pandemic: A Longitudinal Study.

The COVID-19 pandemic and policy measures enacted to contain the spread of the coronavirus have had nationwide psychological effects. This study aimed to assess the impact of the first 15 months of the COVID-19 pandemic on the level of anxiety (GAD-7 scale) and depression (PHQ-9 scale) of the Belgian adult population. A longitudinal study was conducted from April 2020 to June 2021, with 1838 respondents participating in 6 online surveys. Linear mixed models were used to model the associations between the predictor variables and the mental health outcomes. Results showed that the prevalence of symptoms of anxiety and depression was higher in times of stricter policy measures. Furthermore, after the initial stress from the outbreak, coping and adjustment were observed in participants, as symptoms of anxiety and depression decreased during times of lower policy restrictions to almost the same level as in pre-COVID times (2018). Though time trends were similar for all population subgroups, higher levels of both anxiety and depression were generally found among women, young people, people with poor social support, extraverts, people having pre-existing psychological problems, and people who were infected/exposed to the COVID-19 virus. Therefore, investment in mental health treatment programs and supports, especially for those risk groups, is crucial.

Domestic violence during the COVID-19 confinement: do victims feel more socially isolated?

BACKGROUND: Since March 13th 2020, confinement measures have been introduced in Belgium to curb the spread of the coronavirus (COVID-19). These measures also have an impact on people's daily life (closure of school/businesses, teleworking, recommendation to stay at home). This can cause stress on social, economic and psychological levels and thereby can trigger domestic violence. Besides, confinement also fosters social isolation, which can complicate help seeking behaviour. The aim of this study is to determine the prevalence of domestic violence during the coronavirus crisis and to assess whether there is an association between domestic violence and social isolation. METHODS: Several online COVID-19 Health Surveys were organised among Belgian residents aged 18+ via snowball sampling. This study is based on the second (April 2020) and the sixth survey (March 2021). After excluding 1-person households and missing data, the sample size was respectively 25,251 and 12,589. Weighted prevalence of domestic violence was evaluated for the two surveys. The association (OR; 95% CI; p-value) between domestic violence and subjective social isolation was assessed with logistic regression stratified by survey and adjusted for covariates. RESULTS: In April 2020, 4.0% of the adult population reported being a victim of domestic violence (1.2% in the Health Interview Survey 2018); in March 2021, this was 6.2%. In April 2020, victims of domestic violence had higher odds of being unsatisfied with their social contacts (OR = 1.25; 95% CI: 1.08-1.44; p < .05), weak social support (OR = 2.26; 95% CI: 1.97-2.58; p < .0001) and having less confidence in health care services (OR = 1.38; 95% CI: 1.13-1.71; p < .05). In March 2021, victims had higher odds of being unsatisfied with their social contacts (OR = 1.30; 95% CI: 1.08-1.56; p < .05) and weak social support (OR = 2.41; 95% CI: 2.04-2.84; p < .0001), and social (OR = 2.64; 95% CI: 2.23-3.13; p < .0001) and emotional loneliness (OR = 2.22; 95% CI: 1.80-2.73; p < .0001). CONCLUSIONS: More people have reported domestic violence since the start of the coronavirus crisis than did in 2018. An association between domestic violence and social isolation was determined. Although confinement is needed to counteract the virus, it can put people in a dangerous situation since they do not get the help they need. Therefore, adequate support is essential.

Unit Response and Costs in Web Versus Face-To-Face Data Collection: Comparison of Two Cross-sectional Health Surveys.

BACKGROUND: Potential is seen in web data collection for population health surveys due to its combined cost-effectiveness, implementation ease, and increased internet penetration. Nonetheless, web modes may lead to lower and more selective unit response than traditional modes, and this may increase bias in the measured indicators. OBJECTIVE: This research assesses the unit response and costs of a web study versus face-to-face (F2F) study. METHODS: Alongside the Belgian Health Interview Survey by F2F edition 2018 (BHISF2F; net sample used: 3316), a web survey (Belgian Health Interview Survey by Web [BHISWEB]; net sample used: 1010) was organized. Sociodemographic data on invited individuals was obtained from the national register and census linkages. Unit response rates considering the different sampling probabilities of both surveys were calculated. Logistic regression analyses examined the association between mode system and sociodemographic characteristics for unit nonresponse. The costs per completed web questionnaire were compared with the costs for a completed F2F questionnaire. RESULTS: The unit response rate is lower in BHISWEB (18.0%) versus BHISF2F (43.1%). A lower response rate was observed for the web survey among all sociodemographic groups, but the difference was higher among people aged 65 years and older (15.4% vs 45.1%), lower educated people (10.9% vs 38.0%), people with a non-Belgian European nationality (11.4% vs 40.7%), people with a non-European nationality (7.2% vs 38.0%), people living alone (12.6% vs 40.5%), and people living in the Brussels-Capital (12.2% vs 41.8%) region. The sociodemographic characteristics associated with nonresponse are not the same in the 2 studies. Having another European (OR 1.60, 95% CI 1.20-2.13) or non-European nationality (OR 2.57, 95% CI 1.79-3.70) compared to a Belgian nationality and living in the Brussels-Capital (OR 1.72, 95% CI 1.41-2.10) or Walloon (OR 1.47, 95% CI 1.15-1.87) regions compared to the Flemish region are associated with a higher nonresponse only in the BHISWEB study. In BHISF2F, younger people (OR 1.31, 95% CI 1.11-1.54) are more likely to be nonrespondents than older people, and this was not the case in BHISWEB. In both studies, lower educated people have a higher probability of being nonrespondent, but this effect is more pronounced in BHISWEB (low vs high education level: Web, OR 2.71, 95% CI 2.21-3.39 and F2F OR 1.70, 95% CI 1.48-1.95). The BHISWEB study had a considerable advantage; the cost per completed questionnaire was almost 3 times lower (€41 [US $48]) compared with F2F data collection (€111 [US $131]). CONCLUSIONS: The F2F unit response rate was generally higher, yet for certain groups the difference between web and F2F was more limited. Web data collection has a considerable cost advantage. It is therefore worth experimenting with adaptive mixed-mode designs to optimize financial resources without increasing selection bias (eg, only inviting sociodemographic groups who are keener to participate online for web surveys while continuing to focus on increasing F2F response rates for other groups).

Belgian population norms for the EQ-5D-5L, 2018.

PURPOSE: Health-related quality of life outcomes are increasingly used to monitor population health and health inequalities and to assess the (cost-) effectiveness of health interventions. The EQ-5D-5L has been included in the Belgian Health Interview Survey, providing a new source of population-based self-perceived health status information. This study aims to estimate Belgian population norms for the EQ-5D-5L by sex, age, and region and to analyze its association with educational attainment. METHODS: The BHIS 2018 provided EQ-5D-5L data for a nationally representative sample of the Belgian population. The dimension scores and index values were analyzed using logistic and linear regressions, respectively, accounting for the survey design. RESULTS: More than half of respondents reported problems of pain/discomfort, while over a quarter reported problems of anxiety/depression. The average index value was 0.84. Women reported more problems on all dimensions, but particularly on anxiety/depression and pain/discomfort, resulting in significantly lower index values. Problems with mobility, self-care, and usual activities showed a sharp increase after the age of 80 years. Consequently, index values decreased significantly by age. Lower education was associated with a higher prevalence of problems for all dimensions except anxiety/depression and with a significantly lower index value. CONCLUSION: This paper presents the first nationally representative Belgian population norms using the EQ-5D-5L. Inclusion of the EQ-5D in future surveys will allow monitoring over time of self-reported health, disease burden, and health inequalities.

The impact of multimorbidity patterns on health-related quality of life in the general population: results of the Belgian Health Interview Survey.

BACKGROUND: Chronic diseases and multimorbidity are a major cause of disease burden-for patients, caregivers, and society. Little is known however about potential interaction effects between specific disease combinations. Besides an additive effect, the presence of multiple conditions could also act synergistically or antagonistically regarding the impact on patients' health-related quality of life (HRQoL). The aim was to estimate the impact of coexisting chronic diseases on HRQoL of the adult general Belgian population. METHODS: The Belgian Health Interview Survey 2018 provided data on self-reported chronic conditions and HRQoL (EQ-5D-5L) for a nationally representative sample. Linear mixed models were used to analyze two-way and three-way interactions of disease combinations on HRQoL. RESULTS: Multimorbidity had a prevalence of 46.7% (≥ 2 conditions) and 29.7% (≥ 3 conditions). HRQoL decreased considerably with the presence of multiple chronic diseases. 14 out of 41 dyad combinations and 5 out of 13 triad combinations showed significant interactions, with a dominant presence of negative/synergistic effects. Positive/antagonistic effects were found in more subjective chronic diseases such as depression and chronic fatigue. Conditions appearing the most frequently in significant disease pair interactions were dorsopathies, respiratory diseases, and arthropathies. CONCLUSIONS: Diverse multimorbidity patterns, both dyads and triads, were synergistically or antagonistically associated with lower HRQoL. Tackling the burden of multimorbidity is needed, especially because most disease combinations affect each other synergistically, resulting in a greater reduction in HRQoL. Further knowledge about those multimorbidity patterns with a greater impact on HRQoL is needed to better understand disease burden beyond mortality and morbidity data.

Mental health, compliance with measures and health prospects during the COVID-19 epidemic: the role of health literacy.

BACKGROUND: The importance of health literacy in dealing with the COVID-19 epidemic has been emphasized but scarcely addressed empirically. In this study, the association of health literacy with mental health, compliance with COVID-19 preventive measures and health prospects was assessed in a Belgian context. METHODS: Data were extracted from the third of a series of cross-sectional online COVID-related surveys (n = 32,794). Data collection took place for 1 week starting the 28th of May 2020. People residing in Belgium and aged 18 years or older could participate. Data were collected on sociodemographic background, health literacy, multimorbidity, mental health (depression, anxiety, sleeping disorder, vitality), knowledge about COVID-19, compliance with COVID-19 measures (hygiene, physical distance, covering mouth and nose on public transport and in places where physical distance cannot be respected), and health prospects (risk for health when returning to normal life and possibility of infection). Prevalence Ratio (PR) of poor mental health, non-compliance with the measures and health prospects in relation to health literacy were calculated using Poisson regressions. RESULTS: People showing sufficient health literacy were less likely to suffer from anxiety disorders (PR = 0.47, 95% CI = [0.42-0.53]), depression (PR = 0.46, 95% CI = [0.40-0.52]) and sleeping disorders (PR = 0.85, 95% CI = [0.82-0.87]), and more likely to have optimal vitality (PR = 2.41, 95% CI = [2.05-2.84]) than people with low health literacy. They were less at risk of not complying with the COVID-19 measures (PR between 0.60 and 0.83) except one (covering mouth and nose in places where physical distance cannot be respected). Finally, they were less likely to perceive returning to normal life as threatening (PR = 0.70, 95% CI = [0.65-0.77]) and to consider themselves at risk of an infection with COVID-19 (PR = 0.75, 95% CI = [0.67-0.84]). The associations remained significant after controlling for COVID-19 knowledge and multimorbidity. CONCLUSIONS: These results suggest that health literacy is a crucial factor in managing the COVID-19 epidemic and offer a perspective for future studies that target health literacy in the context of virus outbreaks.

Short-term impact of the COVID-19 confinement measures on health behaviours and weight gain among adults in Belgium.

BACKGROUND: In Belgium, confinement measures were introduced on the 13th of March 2020 to curb the spread of the coronavirus disease (COVID-19). These measures may affect health behaviours of the population such as eating habits, physical activity and alcohol consumption, which in turn can lead to weight gain resulting in overweight and obesity, increasing the risk of several chronic diseases, but also of severe COVID-19. The purpose of this study is to assess the impact of confinement measures on health behaviours and their associations with weight gain. METHODS: Data were derived from the second national COVID-19 health survey. Data were collected between the 16th and the 23rd of April 2020. The recruitment of participants was based on snowball sampling via Sciensano's website, invitations via e-mail and social media. The study sample includes participants aged 18 years and over with no missing data on the variables of interest (n = 28,029). The association between self-reported weight gain and health behaviour changes, adjusted for gender, age group and household composition was assessed through OR's (95% CI) calculated with logistic regression models, using post-stratification weights. RESULTS: Overall, 28.6% reported weight gain after 6 weeks of confinement. Higher odds of weight gain were observed among participants who increased or decreased their consumption of sugar-sweetened beverages (OR = 1.39 (1.15-1.68) and 1.29 (1.04-1.60), respectively), among those who increased their consumption of sweet or salty snacks (OR = 3.65 (3.27-4.07)), among those who became less physically active (OR = 1.91 (1.71-2.13)), and among those who increased their alcohol consumption (OR = 1.86 (1.66-2.08)). CONCLUSIONS: The most important correlates of weight gain during confinement were an increased consumption of sweet or salty snacks and being less physically active. These findings confirm the impact of diet and exercise on short term weight gain and plead to take more action, in supporting people to achieve healthier behaviours in order to tackle overweight and obesity, especially during the COVID-19 pandemic.

Food insecurity and its association with changes in nutritional habits among adults during the COVID-19 confinement measures in Belgium.

OBJECTIVE: To assess food insecurity and its association with changes in nutritional habits among Belgian adults during confinement due to COVID-19. DESIGN: Three cross-sectional online health surveys were conducted during March-May 2020. Multinomial logistic regression models were used to determine associations between self-reported changes in fruit, vegetable, soft drink and sweet and salted snack consumption or weight as dependent variables and food insecurity indicators as independent variables, adjusted for gender, household composition, educational attainment and household income. SETTING: Belgium. PARTICIPANTS: In total, 8640 adults recruited by convenience sampling. RESULTS: About 10·4 % of Belgians often or sometimes feared food shortages, 5·0 % were often or sometimes short of food without money to buy more and 10·3 % often or sometimes could not afford to eat a healthy diet during confinement. These percentages were highest among single-parent families (26·7, 14·4 and 23·4 %, respectively). Adults who often or sometimes feared that food would run out during confinement had significantly higher odds of decreased v. unchanged fruits (3·53; 95 % CI = 2·06, 6·05) and vegetables (5·42; 95 % CI = 2·90, 10·11) consumption and significantly higher odds of increased v. unchanged soft drink consumption (3·79; 95 % CI = 2·20, 6·54). Similar results were found for adults who often or sometimes ran out of food and for adults who often or sometimes were not able to afford a healthy diet. CONCLUSION: Food insecurity during the COVID-19 confinement measures in Belgium was associated with adverse changes in most dietary behaviours. A strong government response is needed to tackle malnutrition and food insecurity to protect public health from ongoing and future pandemics.