Research

The research at the chair focuses on the following areas:

  • Trends in morbidity and mortality
  • Life factors of cognitive and physical diseases in old age
  • Risk factors for neurodegenerative diseases such as dementia and Parkinson's disease
  • Health of migrants
  • Health consequences of minimally invasive implant technolog

Current research

Health of Migrants

Prof. Dr. Gabriele Doblhammer

Daniela Georges

Dr. Daniel Kreft

Within the last decade, the proportion of the population with a migration background in Germany has increased from 18.7 % (15.4 million) to 22.5 % (18.6 million). This increase is associated with a growing diversity of the population, which also raises new questions in health research. Migration (or the presence of a migration background) is considered one of the newer dimensions of health inequalities. Previous studies indicate that migrants constitute a vulnerable group within the population and differ both in their risk for diseases and spectrum of diseases as well as in the mechanisms that determine their health status. Our research aim is to identify and quantify these differences with particular focus on mapping the heterogeneity of the migrant population. This heterogeneity refers to numerous characteristics, e.g. the country of origin, the immigration period, the duration of stay, the immigrant generation, the legal status, the motive to migrate, experiences in the process of migration, selection mechanisms etc., and allows different perspectives and differentiation levels. One of the largest migrant groups in Germany are Ethnic German Immigrants ((Spät-)Aussiedler, ca. 3 million), who are characterized by their special legal status and the cultural proximity to the German majority population. Our analyses yield new insights into differences in health, but also similarities between Ethnic German Immigrants, non-migrant Germans and other migrant groups. We can prove that (comparative) health benefits and disadvantages depend on the duration of stay in Germany and the integration into the labour market and varies according to the type of residential area and household characteristics. A good integration into the labour market, living in rural areas and economically powerful regions as well as cohabitating with children has a particularly positive effect. Health disadvantages for Turks – the second large migrant group in Germany (3 million) – were discussed frequently and are mostly attributed to economic and socio-cultural differences. We also show these connections in our research, and find that – besides socio-economic characteristics – also disadvantageous lifestyle factors (obesity, smoking) lead to poorer health among Turkish migrants. Although different patterns in terms of the household and family formation of Turks compared to Germans emerge, the influence of specific household forms is similar for both groups. In the course of the current migration flows, refugee migration is also gaining importance. This acute migration of people from distant countries poses new challenges for both the migrant and the host population. With regard to health, this subgroup within the migrant population highlights the importance of integration on health outcomes. Both high economic and high socio-cultural integration are associated with better health, as our most recent research shows. Subsequent studies aim to identify further determinants of health and health inequalities among migrants, to assess the validity of our findings taking different health outcomes into account and/or to consider other subgroups within the migrant population.

Publications:

[1] Georges, D.; Kreft, D.; Doblhammer, G. (2018): The Contextual and Household Contribution to Individual Health Status in Germany: What is the Role of Gender and Migration Background? In: Gumà, J.; Doblhammer, G. (Eds.): Family and Health from a Gender Perspective in Europe. Springer Brief.

[2] Kreft, D.; Doblhammer, G (2012) Contextual and individual determinants of health among Aussiedler and native Germans. Health & Place 18 (5): 1046–1055. DOI: 10.1016/j.healthplace.2012.05.008

Life Expectancy Free of Care Need

Prof. Dr. Gabriele Doblhammer

Dr. Daniel Kreft

Two of the most discussed questions in public health research are whether there is an expansion or compression of morbidity and whether there are heterogeneous or homogeneous health scenarios on sub-national level. We computed county-specific period life expectancy (LE), disability-free life years (DFLY) and life years with disability (DLY) at age 65+ by sex and care level distinguishing between any and severe care. Databases were aggregate data from the regional database of the National Statistical Office and administrative data of all beneficiaries in Germany from the Statutory Long-Term Care (SLTC) Censuses 2001-2009. We find an overall increase in DFLY which is higher for men than for women and higher for severe than for any care need. We detect a north-east versus south-west gap between counties with low and high level and increase in DFLY and LE. Spatial variation has increased over the period with the majority of counties showing an expansion of any care need, but a compression of severe care need. However, there is a high spatial heterogeneity in terms of the health scenarios which is mainly caused by divergent trends in the prevalence of care need. The study detects an accelerating progress of spatiotemporal inequality in health and longevity. Previous studies have missed to consider that heterogeneity. We show that morbidity is the decisive driver of the health scenarios while it is mortality for the absolute changes in DFLY. Furthermore, the health ratios reveal pronounced spatial clusters which extended beyond the borders of federal states and are linked to the socioeconomic conditions in the respective counties. The cross-sectional perspective suggests that high life expectancy in a county goes together with a high number and large proportion of healthy years spent without disability. The positive correlations are stronger in the West German counties than in the East German counties. Results from meta-regression suggest a significant relationship between a county’s health ratio and the county’s socioeconomic performance, socioeconomic composition, level of urbanization, and health care structure. A high household income per capita, a low long-term unemployment rate, a high population density, and a low level of premature mortality in a county are significantly linked to a high health ratio. Our latest research explores spatial variation in health scenarios by clusters of counties in relation to indicators of aggregate socio-economic conditions.

Publications:

[1] Kreft D.; Doblhammer G. (2016): Expansion or compression of long-term care in Germany between 2001 and 2009? A small-area decomposition study based on administrative health data. Population Health Metrics 14: 24. DOI 10.1186/s12963-016-0093-1.

[2] Kreft D. (2014): Spatial patterns in German long-term care and their relationship with socioeconomic factors. In: Doblhammer G. (Ed.): Health among the elderly in Germany: new evidence on disease, disability and care need. Opladen; Berlin; Toronto: Budrich.

[3] Doblhammer, G.; Kreft, D.; Dethloff, A. (2012): Gewonnene Lebensjahre. Langfristige Trends der Sterblichkeit nach Todesursachen in Deutschland und im internationalen Vergleich, Bundesgesundheitsblatt, 55: 448-458. DOI: 10.1007/s00103-012-1455-x

[4] Doblhammer, G.; Kreft, D. (2011): Länger leben, länger leiden? Trends in der Lebenserwartung und Gesundheit. Bundesgesundheitsblatt, 54: 907-914. DOI: 10.1007/s00103-011-1315-0

[5] Doblhammer, G.; Kreft, D. (2010): Trends and Patterns in Life Expectancy in Europe, 2010 Update. DemoNet report, Den Haag/Brussels.

[6] Steinberg J., Kreft D., Ziegler U., Doblhammer, G. (2010): Home care arrangements in Europe. Determinants and quality of life. DemoNet report, Den Haag/Brussels.

[7] Doblhammer, G.; Kreft, D. (2010): Trends and Patterns in Causes of Death in Europe, 2010 Update. DemoNet report, Den Haag/Brussels.

[8] Doblhammer, G.; Muth, E.; Kreft, D. (2009): Trends and Patterns in Life Expectancy in Europe, DemoNet report, Den Haag/Brussels.

[9] Doblhammer, G.; Muth, E.; Kreft, D. (2009): Trends and Patterns in Causes of Death in Europe, DemoNet report, Den Haag/Brussels. 

Trends in Morbidity and Mortality

Prof. Dr. Gabriele Doblhammer

Dr. Anne Fink

Dr. Thomas Fritze

Michael Nerius

Dementia

Recent studies have been cautiously optimistic about declining trends in dementia prevalence and incidence. Newly available claims data from a German public health insurance company covering thirty per cent of the total population permitted us to explore short-term trends based on millions of observations up to the highest ages. Diagnoses stemmed from the inpatient and outpatient services und covered both the community-dwelling population and those living in nursing homes. Data spanning over three years were examined and revealed a significant yearly reduction between one and two per cent in the prevalence of dementia among women aged 74 to 85 years. The extent of the reduction was comparable to reports from earlier studies. A similar tendency existed among men, however, statistically not significant. Trends in medical, lifestyle and societal risk factors of dementia may have all contributed to this decline In addition, we found a compression of life years with dementia by a yearly 1.4 months for women and half a month for men. The compression was due to declining incidence rates and increasing death rates of the demented. The scale of reduction in the incidence of dementia is comparable to earlier results. In Germany, in the age groups studied here, both sexes profited from the educational expansion after World War I and better living conditions after World War II. In addition vascular risk factors of dementia have declined and are better controlled. Our latest research indicates diverging trends between East and West Germany and that dementia prevalence only declines in West Germany. Since today the health system is similar in both parts of the country, differences in dementia trends may be a legacy of the past related to differences in cardiovascular risk factors over the life-course.

Publications:

 [1] Nerius M., Johnell K., Garcia-Ptacek S., Eriksdotter Jonhagen M., Haenisch B., Doblhammer G. (2017): The Impact of Antipsychotic Drugs on Long-term Care, Nursing Home Admission and Death among Dementia Patients. DOI: 10.1093/gerona/glx239.

[2] Fink, A., Haenisch, B. (2017): Oral antidiabetic drugs and dementia risk: Does treatment matter? Neurology 89(18):1848-1849. DOI: 10.1212/WNL.0000000000004613.

[3] Fritze T., Teipel S., Ovari A., Kilimann I., Witt G., Doblhammer G. (2016): Hearing Impairment Affects Dementia Incidence. An Analysis Based on Longitudinal Health Claims Data in Germany. PLoS One: 2016;11(7):e0156876.

[4] Gomm W., von Holt K., Thomé F., Broich K., Maier W., Werbecker K., Fink A., Doblhammer G., Haenisch B. (2016): Regular Benzodiazepine and Z-Substance Use and Risk of Dementia: An Analysis of German Claims Data. Journal of Alzheimer's Disease 54(2): 801-808. DOI: 10.3233/JAD-151006.

[5] Zhou, Ying; Putter, Hein; Doblhammer, Gabriele (2016): Years of life lost due to lower extremity injury in association with dementia, and care need: a 6-year follow-up population-based study using a multi-state approach among German elderly. In: BMC geriatrics 16, S. 9. DOI: 10.1186/s12877- 016-0184-7.

[6] Barth A., Vatterrott A., Zhou Y., Fink A., Doblhammer G. (2016): Extremity injuries and dementia disproportionately increase the risk for long-term care at older age in an analysis of German Health Insurance routine data for the years 2006 to 2010. European Review of Aging and Physical Activity 13(1). DOI: 10.1186/s11556-016-0169-8.

[7] Gomm W., von Holt K., Thomé F., Broich K., Maier W., Fink A., Doblhammer G., Haenisch B. (2016): Association of Proton Pump Inhibitors With Risk of Dementia: A Pharmacoepidemiological Claims Data Analysis. JAMA Neurology. DOI: 10.1001/jamaneurol.2015.4791.

[8] Teipel S., Fritze T., Ovari A. et al.(2015): Regional Pattern of Dementia and Prevalence of Hearing Impairment in Germany. DOI: 10.1002/lio2.65.

[9] Doblhammer G., Fritze T. (2015): Month of Birth and Dementia Late in Life. In: Hank K., Kreyenfeld M: Social Demography. Forschung an der Schnittstelle von Soziologie und Demografie. KZfSS Kölner Zeitschrift für Soziologie und Sozialpsychologie. 217-240. DOI 10.1007/s11577-015-0328-3.

[10] Doblhammer G., Fritze T., Teipel S. et. al. (2015): Spatial patterns of dementia prevalence and its vascular risk factors in Germany. In: Doblhammer G. (ED):Health among the Elderly in Germany: New Evidence on Disease, Disability and Care Need. Vol 46. Opladen, Berlin, Toronto: Barbara Budrich.

[11] Doblhammer G., Fink A., Zylla S., Willekens F. (2015): Compression or Expansion of Dementia into Old Age in Germany? An Observational Study of Short-Term Trends in Incidence and Death Rates of Dementia between 2006/07 and 2009/10 Based on German Health Insurance Data. Alzheimer's Research & Therapy 7(1): 66-76. DOI: 10.1186/s13195-015-0146-x.

[12] Heneka M. T., Fink A., Doblhammer G. (2015): Effect of pioglitazone medication on the incidence of dementia. Annals of Neurology 78(2): 284-294. DOI: 10.1002/ana.24439.

[13] Fink A., Doblhammer G. (2015): Risk of long-term care dependence for dementia patients is associated with type of physician – An analysis of German health claims data for the years 2006 to 2010. Journal of Alzheimer’s Disease 47(2): 443-452. DOI: 10.3233/JAD-142082.

[14] Doblhammer G., Fink A., Fritze T. (2015): Short-Term Trends in Dementia Prevalence in Germany Between the Years 2007 and 2009. Alzheimer’s & Dementia 11(3): 291-299. DOI: 10.1016/j.jalz.2014.02.006.

[15] Doblhammer G., Fink A., Zylla S., Willekens F. (2015): Compression or expansion of dementia in Germany? An observational study of short-termin trends in incidence and death rates of dementia betweend 2006/07 an 2009/10 based in German health insurance data. Azheimers's Research & Therapy: DOI 10.1186/s13195-015-0146-x.

[16] Fink A. (2014): Dementia and Long-Term Care – An Analysis Based on German Health Insurance Data. In: G. Doblhammer (Ed.): Health among the Elderly in Germany: New Evidence on Disease, Disability and Care Need. Series on Population Studies by the Federal Institute for Population Research, Volume 46, Opladen, Berlin, Toronto: Barbara Budrich, 109-126.

[17] Doblhammer G., Fink A., Fritze T., Günster C. (2013): The Demography and Epidemiology of Dementia. Geriatric Mental Health Care 1(2): 29-33. DOI: 10.1016/j.gmhc.2013.04.002.

[18] Doblhammer G., Schulz A., Steinberg J., Ziegler U. (2012): Demografie der Demenz. Bern: Verlag Hans Huber, Hogrefe AG.

[19] Schulz A, Doblhammer G. (2012): Aktueller und zukünftiger Krankenbestand von Demenz in Deutschland auf Basis der Routinedaten der AOK. In: C. Günster, J. Klose, N. Schmacke: Versorgungs-Report 2012: Schwerpunkt: Gesundheit im Alter. Schattauer GmbH: 161-176.

[20] Ziegler U., Doblhammer G. (2010): Projections of the Number of People with Dementia in Germany 2002 Through 2047. In: Doblhammer G., Scholz R. (eds) Ageing, Care Need and Quality of Life. VS Verlag für Sozialwissenschaften.

[21] Ziegler U.;Doblhammer G. (2009): Prävalenz und Inzidenz von Demenz in Deutschland - Eine Studie auf Basis von Daten der gesetzlichen Krankenversicherungen von 2002. Rostocker Zentrum -Diskussionspapier No. 24. Rostocker Zentrum zur Erforschung des Demografischen Wandels.

Current third-party funded projects

3M Demometry

Prof. Dr. Gabriele Doblhammer

Prof. Dr. Rafael Weißbach

Constantin Reinke

3M Demometry - Multi-time, multi-state, multi-level analysis of health-related demographic events: Statistical aspects and applications

Demographic analysis relies heavily on observations from population-based (longitudinal) studies and large process-generated data such as health-claims data and population registers. In this proposal, we deal with aspects of the multi-state, multi-time and multi-level nature of observational demographic data. Extending survival analysis, health events imply multiple states that preserve the observability of the statistical unit in the course of time. However similarly, erroneous measurements, double censoring and/or truncation result in missing measurements of the time-to-event. As a contemporary method, the EM algorithm has already proved useful for the analysis of demographic data, and especially for hazard estimation, when histories are incomplete. Our specific contribution to demography will be to reveal whether increasing life expectancy results in comparatively more years in good or poor health. Specifically, we focus on dementia, which is among the most common and most expensive diseases in old age. We will draw on methodology designed for the analysis of event histories specific for diseases with similar data generation, namely cancer, tooth decay and HIV. As an aspect of multiple-time axes, we will estimate, at the individual level, to what extent the maximum age and the maximum age-at-dementia diagnosis have increased. For the distribution of the (dementia-free) life duration, we will determine the right endpoint, and its functional relation to time, with recent methods from nonparametric frontier estimation. Demographic data are usually equipped with dependencies, be it longitudinal or in the cross-section. We will acknowledge its inflationary effect on the standard error by studying dependency models, like the Markovian property, and by employing methods from sampling techniques, like cluster-sampling.

RESPONSE - Health consequences of minimally invasive implant technologies

RESPONSE - Health consequences of minimally invasive implant technologies

Prof. Dr. Gabriele Doblhammer

Dipl.-Pol. Alexander Barth

Dr. Daniel Kreft

Due to the demographic development, which will lead to about 29% of the German population being over 65 years old in 2030, the multimorbidity of the population will be an ever greater social problem with chronic disease progression. According to a survey by the Robert Koch Institute, according to the 2003 Federal Health Survey, the incidence of multimorbid disease states in the age group 40-49 years was 36% for men and 51% for women. In the 70-79 age group, this incidence increased to 70% for men and 80% for women, which corresponds to an estimated absolute number of multimorbid patients in this age group of approximately 7-9.5 million in 2030. Thus, with increasing life expectancy, the multiple-diseased and impaired in its functionality, human will be the determining reality in the supply, which must also be considered in medical technology. In addition, an overall decline in population leads to a greater decline in the number of people in work, which requires additional efforts to maintain work capacity and to shorten the course of illness by taking effective and gentle treatment procedures. Within the RESPONSE project, the individual and societal benefits as well as the quality of life gained through implant innovations are to be quantified and, as far as possible, the associated costs are to be determined. The aim is to develop and apply methods of health and patient-oriented system and innovation research to evaluate implant innovations for the cardiovascular system, eye and ear against the background of maintaining the quality of life, ability to work, self-determined living of an aging population and in particular the inclusion of the patient perspective. Potentially, the use of new implants promises cost savings by reducing the overall burden of morbidity, reducing the use of medication, maintaining autonomy, and delaying the onset of long-term care. In this context, it is necessary to forecast the requirements as well as the demand on the national and international markets, which is derived from the demographic and technological perspectives as well as patient preferences. It is important to understand the acceptance of the medical prescriptions as well as the long-term success of the surgical interventions by appropriate demographic methods. Demographic and statistical analyzes of the impact of implants on morbidity, care needs and longevity at population level will be carried out. The aim is the measurement of the implant supply (incidence, prevalence and risk factors) and their consequences (mortality and care needs) in the data of the general local health insurance funds (AOK). In addition, the consequences of implant-related morbidity are evaluated with the reins data of the pension insurance with regard to the maintenance of earning capacity.

RESPONSE-Website

Publications:

[1] Barth, A., Yücel, S., Ince, H., Doblhammer, G.: The impact of transcatheter aortic valve implantation on the risk of mortality in patients with severe aortic valve diseases. A health insurance based analysis, in finaler Bearbeitung.

[2] Frech, S., Kreft, D., Guthoff, RF., Doblhammer, G.: Pharmacoepidemiological assessment of adherence and influencing co-factors among primary open-angle glaucoma patients – an observational cohort study, eingereicht.

[3] Kreft, D., Guthoff, RF., Doblhammer, G., Frech, S.: Prevalence, Incidence and Risk Factors of Primary Open-Angle Glaucoma - a cohort study based on longitudinal data from a German public health insurance, eingereicht.