title: Prevalence and determinants of overweight and obesity in old age in Germany.
abstract: BACKGROUND
  Mean body weight gradually increases with age. Yet, little data exists on the prevalence of excess weight in populations aged 80 years or older. Moreover, little is known about predictors of overweight and obesity in old age. Thus, the purpose of this study was: To present data on the prevalence of excess weight in old age in Germany, to investigate predictors of excess weight in a cross-sectional approach and to examine factors affecting excess weight in a longitudinal approach.
  
  
  METHODS
  Subjects consisted of 1,882 individuals aged 79 years or older. The course of excess weight was observed over 3 years. Excess weight was defined as follows: Overweight (25 kg/m(2) ≤ BMI < 30 kg/m(2)) and obesity (BMI ≥ 30 kg/m(2)). We used fixed effects regressions to estimate effects of time dependent variables on BMI, and overweight or obesity, respectively.
  
  
  RESULTS
  The majority was overweight (40.0%) or obese (13.7%). Cross-sectional regressions revealed that BMI was positively associated with younger age, severe walking impairments and negatively associated with cognitive impairments. Excess weight was positively associated with younger age, elementary education, walking impairments and physical inactivity, while excess weight was negatively associated with cognitive impairment. Longitudinal regressions showed that age and severely impaired walking disabilities reduced BMI. The probability of transitions to excess weight decreased considerably with older age and occurrence of severe walking impairments (overweight).
  
  
  CONCLUSIONS
  Marked differences between predictors in cross- and longitudinal setting exist, underlining the complex nature of excess weight in old age.
authors.affiliation: Department of Health Economics and Health Services Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. a.hajek@uke.de.
authors.forename: André
authors.initials: A
authors.lastname: Hajek
authors.affiliation: Department of Health Economics and Health Services Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. t.lehnert@uke.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Lehnert
authors.affiliation: Department of Primary Medical Care, Center for Psychosocial Medicine, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany. a.ernst@uke.de.
authors.forename: Annette
authors.initials: A
authors.lastname: Ernst
authors.affiliation: Department of Primary Medical Care, Center for Psychosocial Medicine, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany. car.lange@uke.de.
authors.forename: Carolin
authors.initials: C
authors.lastname: Lange
authors.affiliation: Institute of General Practice, Hannover Medical School, Hannover, Germany. wiese.birgitt@mh-hannover.de.
authors.forename: Birgitt
authors.initials: B
authors.lastname: Wiese
authors.affiliation: Institute of General Practice, Hannover Medical School, Hannover, Germany. Prokein.Jana@mh-hannover.de.
authors.forename: Jana
authors.initials: J
authors.lastname: Prokein
authors.affiliation: Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany. siegfried.weyerer@zi.mannheim.de.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Weyerer
authors.affiliation: Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany. jochen.werle@zi-mannheim.de.
authors.forename: Jochen
authors.initials: J
authors.lastname: Werle
authors.affiliation: Institute of General Practice, Medical Faculty Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany. Pentzek@med.uni-duesseldorf.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Pentzek
authors.affiliation: Institute of General Practice, Medical Faculty Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany. angela.fuchs@med.uni-duesseldorf.de.
authors.forename: Angela
authors.initials: A
authors.lastname: Fuchs
authors.affiliation: Institute of Social Medicine, Occupational Health and Public Health, University of Leipzig, Leipzig, Germany. Tobias.Luck@medizin.uni-leipzig.de.
authors.forename: Tobias
authors.initials: T
authors.lastname: Luck
authors.affiliation: Department of Psychiatry, Technical University of Munich, Munich, Germany. h.bickel@lrz.tu-muenchen.de.
authors.forename: Horst
authors.initials: H
authors.lastname: Bickel
authors.affiliation: Department of Psychiatry, Technical University of Munich, Munich, Germany. moesch@lrz.tu-muenchen.de.
authors.forename: Edelgard
authors.initials: E
authors.lastname: Mösch
authors.affiliation: Department of Psychiatry, University of Bonn, Bonn, Germany. Kathrin.Heser@ukb.uni-bonn.de.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Heser
authors.affiliation: Department of Psychiatry, University of Bonn, Bonn, Germany. michael.wagner@uni-bonn.de.|German Center for Neurodegenerative Diseases, Bonn, Germany. michael.wagner@uni-bonn.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Wagner
authors.affiliation: Department of Psychiatry, University of Bonn, Bonn, Germany. wolfgang.maier@ukb.uni-bonn.de.|German Center for Neurodegenerative Diseases, Bonn, Germany. wolfgang.maier@ukb.uni-bonn.de.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Maier
authors.affiliation: Department of Primary Medical Care, Center for Psychosocial Medicine, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany. m.scherer@uke.de.
authors.forename: Martin
authors.initials: M
authors.lastname: Scherer
authors.affiliation: Institute of Social Medicine, Occupational Health and Public Health, University of Leipzig, Leipzig, Germany. steffi.riedel-heller@medizin.uni-leipzig.de.
authors.forename: Steffi G
authors.initials: SG
authors.lastname: Riedel-Heller
authors.affiliation: Department of Health Economics and Health Services Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. h.koenig@uke.de.
authors.forename: Hans-Helmut
authors.initials: HH
authors.lastname: König
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D015984:Causality; D003071:Cognition; D003072:Cognition Disorders / Q000453:epidemiology / Q000503:physiopathology; D015986:Confounding Factors, Epidemiologic; D003430:Cross-Sectional Studies; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D051346:Mobility Limitation; D009043:Motor Activity; D009765:Obesity / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology / Q000523:psychology; D015995:Prevalence; D012720:Severity of Illness Index; D012959:Socioeconomic Factors