A decade of socioeconomic inequality in type 2 diabetes area-level prevalence: an unshakeable status quo?

AIMS: It is well known that there is a socioeconomic gradient in the prevalence of many chronic diseases, including type 2 diabetes (T2DM). We present a simple assessment of the macro-level association between area socioeconomic disadvantage and the area-level prevalence of T2DM in Danish municipalities and the development in this relationship over the last decade. METHODS: We used readily available public data on the socioeconomic composition of municipalities and T2DM prevalence to illustrate this association and report the absolute and relative summary measures of socioeconomic inequality over the time period 2008-2018. RESULTS: The results show a persistent relationship between municipality socioeconomic disadvantage and T2DM prevalence across all analyses, with a modelled gap in T2DM prevalence between the most and least disadvantaged municipalities, the slope index of inequality, of 1.23 [0.97;1.49] in 2018. CONCLUSIONS: These results may be used to indicate areas with specific needs, to encourage systematic monitoring of socioeconomic gradients in health, and to provide a descriptive backdrop for a discussion of how to tackle these socioeconomic and geographic inequalities, which seem to persist even in the context of the comprehensive welfare systems in Scandinavia.

Joint effects of educational attainment, type 2 diabetes and coexisting morbidity on disability pension: results from a longitudinal, nationwide, register-based study.

AIMS/HYPOTHESIS: High prevalence of coexisting morbidity in people with type 2 diabetes highlights the need to include interactions with education and comorbidity in the assessments of societal consequences of type 2 diabetes. The purpose of this study was to estimate the joint effects of education, type 2 diabetes and six frequent comorbidities. METHODS: Nationwide administrative register data on type 2 diabetes diagnosis, hospital admissions, education and disability pension were grouped at the individual level by means of a unique personal identification number. Included were all people (N = 2,281,599) in the age span of 40-59 years living in Denmark in the period 2005 to 2017, covering a total of 17,754,788 person-years. We used both Cox proportional hazards and Aalen additive hazards models to estimate relative and absolute joint effects of type 2 diabetes, educational attainment and six common comorbidities (CVD, cancer and cerebrovascular, respiratory, musculoskeletal and psychiatric diseases). We decomposed the joint effects of educational level, type 2 diabetes and comorbidities into main effects and the interaction effect, measured as extra cases of disability pension. RESULTS: Lower level of educational attainment, type 2 diabetes and comorbidities independently contributed to additional granted disability pensions. The joint number of cases of disability pension exceeded the sum of the three exposures, which is explained by a synergistic effect of lower educational level, type 2 diabetes and comorbidity. CONCLUSIONS/INTERPRETATION: In this population study, the joint effects of type 2 diabetes, lower education and comorbidity were associated with larger than additive rates of disability pension. An integrated approach that takes into account socioeconomic barriers to type 2 diabetes rehabilitation may slow down disease progression and increase the working ability of socially disadvantaged people.

A health inequality impact assessment from reduction in overweight and obesity.

BACKGROUND: In recent years, social differences in overweight and obesity (OWOB) have become more pronounced. Health impact assessments provide population-level scenario evaluations of changes in disease prevalence and risk factors. The objective of this study was to simulate the health effects of reducing the prevalence of overweight and obesity in populations with short and medium education. METHODS: The DYNAMO-HIA tool was used to conduct a health inequality impact assessment of the future reduced disease prevalence (ischemic heart disease (IHD), diabetes, stroke, and multi-morbidity) and changes in life expectancy for the 2040-population of Copenhagen, Denmark (n = 742,130). We simulated an equalized weight scenario where the prevalence of OWOB in the population with short and medium education was reduced to the levels of the population with long education. RESULTS: A higher proportion of the population with short and medium education were OWOB relative to the population with long education. They also had a higher prevalence of cardiometabolic diseases. In the equalized weight scenario, the prevalence of diabetes in the population with short education was reduced by 8-10% for men and 12-13% for women. Life expectancy increased by one year among women with short education. Only small changes in prevalence and life expectancy related to stroke and IHD were observed. CONCLUSION: Reducing the prevalence of OWOB in populations with short and medium education will reduce the future prevalence of cardiometabolic diseases, increase life expectancy, and reduce the social inequality in health. These simulations serve as reference points for public health debates.

A conflict of interest is strongly associated with tobacco industry-favourable results, indicating no harm of e-cigarettes.

Researchers reach contradictory results when trying to assess the potential harm of e-cigarettes. This study investigated whether the findings and conclusions in papers published on e-cigarettes and health differ depending on whether the authors had a financial conflict of interest (COI) or not. A total of 94 studies (identified in a previous systematic review) that investigated the content of fluid/vapor of e-cigarettes or in vitro experiments were included. The type, level and direction of the financial COI were coded. Abstracts were blinded and evaluated by two assessors. Fischer's Test and Logistic regression analyses were used to investigate the associations between findings of harm/conclusions and COI. All three dimensions of COI showed the same tendency: studies with industry-related COI found potential harm significantly less often than studies without a COI. 95.1% of papers without and 39.4% of papers with a COI found potential harmful effects/substances. Only 7.7% of tobacco industry-related studies found potential harm. The odds of finding of no harm were significantly higher in studies with an industry-related COI (OR 66.92 (95% CI 8.1-552.9)) than in studies without a COI. A strong/moderate COI was associated with very high odds (OR 91.50 (95% CI 10.9-771.4)) of finding of no harm compared with studies with no/weak COI. This blinded assessment showed that almost all papers without a COI found potentially harmful effects of e-cigarettes. There was a strong association between industry-related COI and tobacco- and e-cigarette industry-favourable results, indicating that e-cigarettes are harmless.

Is self-selection the main driver of positive interpretations of general health checks? The Inter99 randomized trial.

OBJECTIVE: To investigate if the lower mortality among participants of a health check followed by lifestyle intervention of high risk persons is explained by self-selection. METHODS: All persons residing in the study area (Copenhagen; Denmark) were randomized to intervention (n=11,629) or control group (n=47,987). Persons in the intervention group were invited for a health check and individual lifestyle counselling. At baseline, 52.5% participated. Differences between participants and control group in 10-year all-cause and disease specific mortality was assessed. In survival analyses we controlled for socio-demography and mental and physical health. RESULTS: Mortality rates were highest among non-participants and lowest among participants in the intervention group, whereas mortality rates of controls were approximately the average of those of participants and non-participants. In adjusted analyses the difference in both all-cause mortality (HR 0.73, 95% CI 0.62-0.85) and disease specific mortality was diminished between participants and controls, and turning insignificant as regard cancer mortality. In total, 39% of the lower mortality among participants in the intervention group was explained by self-selection according to socio-demography and health. CONCLUSION: A substantial part of the lower mortality among participants in a preventive health check can be explained by confounding. The remaining lower mortality is most probably due to residual confounding, as the lower mortality was seen both for lifestyle related and non-lifestyle related diseases.

Neighborhood social capital is associated with participation in health checks of a general population: a multilevel analysis of a population-based lifestyle intervention- the Inter99 study.

BACKGROUND: Participation in population-based preventive health check has declined over the past decades. More research is needed to determine factors enhancing participation. The objective of this study was to examine the association between two measures of neighborhood level social capital on participation in the health check phase of a population-based lifestyle intervention. METHODS: The study population comprised 12,568 residents of 73 Danish neighborhoods in the intervention group of a large population-based lifestyle intervention study - the Inter99. Two measures of social capital were applied; informal socializing and voting turnout. RESULTS: In a multilevel analysis only adjusting for age and sex, a higher level of neighborhood social capital was associated with higher probability of participating in the health check. Inclusion of both individual socioeconomic position and neighborhood deprivation in the model attenuated the coefficients for informal socializing, while voting turnout became non-significant. CONCLUSION: Higher level of neighborhood social capital was associated with higher probability of participating in the health check phase of a population-based lifestyle intervention. Most of the association between neighborhood social capital and participation in preventive health checks can be explained by differences in individual socioeconomic position and level of neighborhood deprivation. Nonetheless, there seems to be some residual association between social capital and health check participation, suggesting that activating social relations in the community may be an avenue for boosting participation rates in population-based health checks. TRIAL REGISTRATION: ClinicalTrials.gov (registration no. NCT00289237 ).

Equity of referrals to type 2 diabetes rehabilitation in a universal welfare state.

Objective: Despite aims of equal access to treatment and care in the Nordic countries, marked socioeconomic inequality in the development of type 2 diabetes (T2D) complications persists. The study purpose was to estimate the associations of individual socioeconomic position and deprivation at the general practitioner (GP) level with referrals to T2D rehabilitation.Research Design and Methods: In 2015-2018, 3390 people affiliated with 432 primary GPs living in the municipality of Copenhagen were identified through registry data as newly diagnosed with T2D. Of these, 656 (19%) individuals were referred to municipal rehabilitation services in 2015-2021. Individual socioeconomic position was measured by education, income, and employment. The Danish Deprivation Index (DADI) was used as a measure of GP-level deprivation. Results: Patients were more likely to be referred to municipal rehabilitation if they had low vs. high income (hazard ratio (HR) 2.87 [women], 1.64 [men]), were not employed vs. employed (HR 1.95 [women], 1.23 [men]) and were affiliated with GPs with a low vs. very high level of deprivation (HR 7.63 [women], 4.30 [men]). The results suggest that GPs practice proportionate universalism by allocating treatment to lower socioeconomic individuals in likely higher need of care. However, the overall HR for referrals was lower among GPs with more deprived patient populations, indicating unequal treatment of all citizens, which conflicts with the aims of general universal health care. Inequality in rehabilitation healthcare services must be further addressed and investigated to prevent exacerbating health disparities.

Mediating role of multimorbidity in inequality in mortality: a register study on the Danish population.

BACKGROUND: The social inequality in mortality is due to differential incidence of several disorders and injury types, as well as differential survival. The resulting clustering and possible interaction in disadvantaged groups of several disorders make multimorbidity a potentially important component in the health divide. This study decomposes the effect of education on mortality into a direct effect, a pure indirect effect mediated by multimorbidity and a mediated interaction between education and multimorbidity. METHODS: The study uses the Danish population registers on the total Danish population aged 45-69 years. A multimorbidity index based on all somatic and psychiatric hospital contacts as well as prescribed medicines includes 22 diagnostic groups weighted together by their 5 years mortality risk as weight. The Aalen additive hazard model is used to estimate and decompose the 5 years risk difference in absolute numbers of deaths according to educational status. RESULTS: Most (69%-79%) of the effect is direct not involving multimorbidity, and the mediated effect is for low educated women 155 per 100 000 of which 87 is an effect of mediated interaction. For low educated men, the mediated effect is 250 per 100 000 of which 93 is mediated interaction. CONCLUSION: Multimorbidity plays an important role in the social inequality in mortality among middle aged in Denmark and mediated interaction represents 5%-17%. As multimorbidity is a growing challenge in specialised health systems, the mediated interaction might be a relevant indicator of inequities in care of multimorbid patients.

Simulations of future cardiometabolic disease and life expectancy under counterfactual obesity reduction scenarios.

The aim of this study was to provide decision makers with an assessment of potential future health effects of interventions against overweight and obesity (OWOB). By means of the DYNAMO-HIA tool we conducted a health impact assessment simulating future prevented disease (ischemic heart disease (IHD), diabetes, stroke, and multi morbidity) incidence, prevalence and life expectancy (LE) related to a scenario where OWOB is reduced by 25% and a scenario where obesity is eliminated. The study covered projected number of persons living in Copenhagen, Denmark during year 2014-2040 (n 2040 = 742,129). Reducing the proportion of men/women with OWOB with 25% will increase population LE by 2.4/1.2 months and at the same time decrease LE with diabetes by 3.1/2.2 months. As a result of eliminating obesity, total LE will increase by 6.0/3.6 months and LE with diabetes will decrease with 9.8/10.3 months for men/women. We found no important effects on LE with IHD and stroke. This illustrates that the positive effects of lowering OWOB levels on IHD and stroke incidence is offset due to increasing total LE. Although the population of Copenhagen is relatively lean, reducing obesity levels will result in significant benefits for population cardiometabolic health status and LE. Future public health prevention programs may use the results as reference data for potential impact of reductions in OWOB.

Higher mortality in women living in high-participation areas of a population-based health check and lifestyle intervention study.

OBJECTIVES: The aim was to study whether the effects of a population-based health check and lifestyle intervention differed according to study participation rate. METHODS: All persons living in 73 areas of Copenhagen County, Denmark, were included in the Inter99 randomized trial in 1999 (intervention group n = 11,483; control group n = 47,122). All persons in the intervention group were invited for health checks and were offered lifestyle counseling if they were at high risk of ischemic heart disease. Areas were divided into low 35-49%, middle 50-54% and high ≥ 55% health check participation. All persons were followed in registers for 10-year cause-specific mortality. RESULTS: In high-participation areas, there was a significantly higher risk of lifestyle-(HR 1.37 [1.04, 1.79]) and cancer-related deaths (HR 1.47 [1.08, 2.02]) among women in the intervention group than control group. Regarding smoking-related cancer deaths, differences were even more pronounced. Among men, no significant difference in mortality was seen between control and intervention groups. CONCLUSIONS: The results of this paper suggest that among women, the health check and lifestyle intervention may increase the risk of lifestyle and cancer-related deaths.

Assessment of impact of traffic-related air pollution on morbidity and mortality in Copenhagen Municipality and the health gain of reduced exposure.

BACKGROUND: Health impact assessment (HIA) of exposure to air pollution is commonly based on city level (fine) particle concentration and may underestimate health consequences of changing local traffic. Exposure to traffic-related air pollution can be assessed at a high resolution by modelling levels of nitrogen dioxide (NO2), which together with ultrafine particles mainly originate from diesel-powered vehicles in urban areas. The purpose of this study was to estimate the health benefits of reduced exposure to vehicle emissions assessed as NO2 at the residence among the citizens of Copenhagen Municipality, Denmark. METHODS: We utilized residential NO2 concentrations modelled by use of chemistry transport models to calculate contributions from emission sources to air pollution. The DYNAMO-HIA model was applied to the population of Copenhagen Municipality by using NO2 concentration estimates combined with demographic data and data from nationwide registers on incidence and prevalence of selected diseases, cause specific mortality, and total mortality of the population of Copenhagen. We used exposure-response functions linking NO2 concentration estimates at the residential address with the risk of diabetes, cardiovascular diseases, and respiratory diseases derived from a large Danish cohort study with the majority of subjects residing in Copenhagen between 1971 and 2010. Different scenarios were modelled to estimate the dynamic impact of NO2 exposure on related diseases and the potential health benefits of lowering the NO2 level in the Copenhagen Municipality. RESULTS: The annual mean NO2 concentration was 19.6 µg/m3 and for 70% of the population the range of exposure was between 15 and 21 µg/m3. If NO2 exposure was reduced to the annual mean rural level of 6 µg/m3, life expectancy in 2040 would increase by one year. The greatest gain in disease-free life expectancy would be lifetime without ischemic heart disease (1.4 years), chronic obstructive pulmonary disease (1.5 years for men and 1.6 years for women), and asthma (1.3 years for men and 1.5 years for women). Lowering NO2 exposure by 20% would increase disease-free life expectancy for the different diseases by 0.3-0.5 years. Using gender specific relative risks affected the results. CONCLUSIONS: Reducing the NO2 exposure by controlling traffic-related air pollution reduces the occurrence of some of the most prevalent chronic diseases and increases life expectancy. Such health benefits can be quantified by DYNAMO-HIA in a high resolution exposure modelling. This paper demonstrates how traffic planners can assess health benefits from reduced levels of traffic-related air pollution.

Neighborhood deprivation is strongly associated with participation in a population-based health check.

BACKGROUND: We sought to examine whether neighborhood deprivation is associated with participation in a large population-based health check. Such analyses will help answer the question whether health checks, which are designed to meet the needs of residents in deprived neighborhoods, may increase participation and prove to be more effective in preventing disease. In Europe, no study has previously looked at the association between neighborhood deprivation and participation in a population-based health check. METHODS: The study population comprised 12,768 persons invited for a health check including screening for ischemic heart disease and lifestyle counseling. The study population was randomly drawn from a population of 179,097 persons living in 73 neighborhoods in Denmark. Data on neighborhood deprivation (percentage with basic education, with low income and not in work) and individual socioeconomic position were retrieved from national administrative registers. Multilevel regression analyses with log links and binary distributions were conducted to obtain relative risks, intraclass correlation coefficients and proportional change in variance. RESULTS: Large differences between neighborhoods existed in both deprivation levels and neighborhood health check participation rate (mean 53%; range 35-84%). In multilevel analyses adjusted for age and sex, higher levels of all three indicators of neighborhood deprivation and a deprivation score were associated with lower participation in a dose-response fashion. Persons living in the most deprived neighborhoods had up to 37% decreased probability of participating compared to those living in the least deprived neighborhoods. Inclusion of individual socioeconomic position in the model attenuated the neighborhood deprivation coefficients, but all except for income deprivation remained statistically significant. CONCLUSION: Neighborhood deprivation was associated with participation in a population-based health check in a dose-response manner, in which increasing neighborhood deprivation was associated with decreasing participation. This suggests the need to develop preventive health checks tailored to deprived neighborhoods.