[Skip to Content]
[Skip to Content Landing]

Association of Household Income With Life Expectancy and Cause-Specific Mortality in Norway, 2005-2015

Educational Objective
To learn whether there are income-related differences in life expectancy and causes of death in Norway and how they compare with US estimates.
1 Credit CME
Key Points

Question  In Norway, a country with a largely tax-financed universal health care system and moderate income differences, does life expectancy vary with income, and are differences comparable to differences in the United States?

Findings  In this registry-based study that included data from 3 041 828 persons aged at least 40 years in Norway between 2005 and 2015, the difference in life expectancy between the richest and poorest 1% was 8.4 years for women and 13.8 years for men. The differences widened between 2005 and 2015 and were comparable to those in the United States.

Meaning  Inequalities in life expectancy by income in Norway were substantial and increased between 2005 and 2015.

Abstract

Importance  Examining causes of death and making comparisons across countries may increase understanding of the income-related differences in life expectancy.

Objectives  To describe income-related differences in life expectancy and causes of death in Norway and to compare those differences with US estimates.

Design and Setting  A registry-based study including all Norwegian residents aged at least 40 years from 2005 to 2015.

Exposures  Household income adjusted for household size.

Main Outcomes and Measures  Life expectancy at 40 years of age and cause-specific mortality.

Results  In total, 3 041 828 persons contributed 25 805 277 person-years and 441 768 deaths during the study period (mean [SD] age, 59.3 years [13.6]; mean [SD] number of household members per person, 2.5 [1.3]). Life expectancy was highest for women with income in the top 1% (86.4 years [95% CI, 85.7-87.1]) which was 8.4 years (95% CI, 7.2-9.6) longer than women with income in the lowest 1%. Men with the lowest 1% income had the lowest life expectancy (70.6 years [95% CI, 69.6-71.6]), which was 13.8 years (95% CI, 12.3-15.2) less than men with the top 1% income. From 2005 to 2015, the differences in life expectancy by income increased, largely attributable to deaths from cardiovascular disease, cancers, chronic obstructive pulmonary disease, and dementia in older age groups and substance use deaths and suicides in younger age groups. Over the same period, life expectancy for women in the highest income quartile increased 3.2 years (95% CI, 2.7-3.7), while life expectancy for women in the lowest income quartile decreased 0.4 years (95% CI, −1.0 to 0.2). For men, life expectancy increased 3.1 years (95% CI, 2.5-3.7) in the highest income quartile and 0.9 years (95% CI, 0.2-1.6) in the lowest income quartile. Differences in life expectancy by income levels in Norway were similar to differences observed in the United States, except that life expectancy was higher in Norway in the lower to middle part of the income distribution in both men and women.

Conclusions and Relevance  In Norway, there were substantial and increasing gaps in life expectancy by income level from 2005 to 2015. The largest differences in life expectancy between Norway and United States were for individuals in the lower to middle part of the income distribution.

Sign in to take quiz and track your certificates

Buy This Activity

JN Learning™ is the home for CME and MOC from the JAMA Network. Search by specialty or US state and earn AMA PRA Category 1 CME Credit™ from articles, audio, Clinical Challenges and more. Learn more about CME/MOC

Article Information

Accepted for Publication: April 10, 2019.

Corresponding Author: Jonas Minet Kinge, PhD, Norwegian Institute of Public Health, Postboks 222-Skøyen, 0213 Oslo, Norway (Jonas.Minet.Kinge@fhi.no).

Published Online: May 13, 2019. doi:10.1001/jama.2019.4329

Author Contributions: Dr Kinge had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Kinge, Modalsli, Øverland, Vollset.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: Kinge, Modalsli, Øverland, Skirbekk, Håberg.

Critical revision of the manuscript for important intellectual content: Kinge, Modalsli, Øverland, Gjessing, Tollånes, Knudsen, Strand, Håberg, Vollset.

Statistical analysis: Kinge, Modalsli, Gjessing, Håberg, Vollset.

Obtained funding: Øverland, Vollset.

Administrative, technical, or material support: Kinge, Øverland, Vollset.

Supervision: Kinge, Strand, Vollset.

Conflict of Interest Disclosures: Dr Kinge reported receiving grants from the Research Council of Norway during the conduct of the study. Dr Gjessing reported receiving grants from the Research Council of Norway during the conduct of the study and outside the submitted work. Dr Håberg reported receiving grants from the Research Council of Norway during the conduct of the study. No other disclosures were reported.

Funding/Support: This work was funded by the Research Council of Norway through FRIPRO (project number 262030), its Centres of Excellence funding scheme (project number 262700), and by the Norwegian Institute of Public Health.

Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

References
1.
Chetty  R, Stepner  M, Abraham  S,  et al.  The association between income and life expectancy in the United States, 2001-2014.  JAMA. 2016;315(16):1750-1766. doi:10.1001/jama.2016.4226PubMedGoogle ScholarCrossref
2.
Mackenbach  JP, Stirbu  I, Roskam  A-JR,  et al; European Union Working Group on Socioeconomic Inequalities in Health.  Socioeconomic inequalities in health in 22 European countries.  N Engl J Med. 2008;358(23):2468-2481. doi:10.1056/NEJMsa0707519PubMedGoogle ScholarCrossref
3.
Kinge  JM, Vallejo-Torres  L, Morris  S.  Income related inequalities in avoidable mortality in Norway: a population-based study using data from 1994-2011.  Health Policy. 2015;119(7):889-898. doi:10.1016/j.healthpol.2015.04.016PubMedGoogle ScholarCrossref
4.
Mortensen  LH, Rehnberg  J, Dahl  E,  et al.  Shape of the association between income and mortality: a cohort study of Denmark, Finland, Norway and Sweden in 1995 and 2003.  BMJ Open. 2016;6(12):e010974. doi:10.1136/bmjopen-2015-010974PubMedGoogle ScholarCrossref
5.
Östergren  O, Martikainen  P, Tarkiainen  L, Elstad  JI, Brønnum-Hansen  H.  Contribution of smoking and alcohol consumption to income differences in life expectancy: evidence using Danish, Finnish, Norwegian and Swedish register data.  J Epidemiol Community Health. 2019:73(4):334-339. doi:10.1136/jech-2018-211640PubMedGoogle ScholarCrossref
6.
Adler  NE, Glymour  MM, Fielding  J.  Addressing social determinants of health and health inequalities.  JAMA. 2016;316(16):1641-1642. doi:10.1001/jama.2016.14058PubMedGoogle ScholarCrossref
7.
Marmot  M, Atkinson  T, Bell  J, Black  C, Broadfoot  P, Cumberlege  J. Fair Society, Healthy Lives: Strategic Review of Health Inequalities in England, Post-2010. London, England: The Marmot Review; 2010.
8.
The world wealth and income database. World Inequality Database website. https://wid.world. Published 2016. Accessed March 5, 2019.
9.
OECD. Income inequality. OECD website. https://data.oecd.org/inequality/income-inequality.htm. Accessed February 8, 2018.
10.
OECD income distribution database (IDD): Gini, poverty, income, methods and concepts. OECD website. http://www.oecd.org/social/income-distribution-database.htm. Accessed February 8, 2018.
11.
Population. Statistics Norway website. https://www.ssb.no/en/befolkning/statistikker/folkemengde. Published 2017. Accessed April 26, 2019.
12.
Nybom  M, Stuhler  J.  Biases in standard measures of intergenerational income dependence.  J Hum Resour. 2017;52(3):800-825. doi:10.3368/jhr.52.3.0715-7290RGoogle ScholarCrossref
13.
Singh  GK, Hiatt  RA.  Trends and disparities in socioeconomic and behavioural characteristics, life expectancy, and cause-specific mortality of native-born and foreign-born populations in the United States, 1979-2003.  Int J Epidemiol. 2006;35(4):903-919. doi:10.1093/ije/dyl089PubMedGoogle ScholarCrossref
14.
Kibele  E, Scholz  R, Shkolnikov  VM.  Low migrant mortality in Germany for men aged 65 and older: fact or artifact?  Eur J Epidemiol. 2008;23(6):389-393. doi:10.1007/s10654-008-9247-1PubMedGoogle ScholarCrossref
15.
Strøm  F.  Persons Without Registered Income or Fortune [in Norwegian]. Vol 87. Oslo, Norway: Statistics Norway; 2004.
16.
OECD.  An overview of growing income inequalities in OECD countries: main findings. Paris, France: OECD; 2011. https://www.oecd.org/els/soc/49499779.pdf.
17.
Dødsårsaksregisteret [Cause of Death Registry]. Norwegian Institute of Public Health. Accessed March 6, 2019.
18.
GBD 2017 SDG Collaborators.  Measuring progress from 1990 to 2017 and projecting attainment to 2030 of the health-related Sustainable Development Goals for 195 countries and territories: a systematic analysis for the Global Burden of Disease Study 2017.  Lancet. 2018;392(10159):2091-2138. doi:10.1016/S0140-6736(18)32281-5PubMedGoogle ScholarCrossref
19.
Eriksson  A, Stenlund  H, Ahlm  K,  et al.  Accuracy of death certificates of cardiovascular disease in a community intervention in Sweden.  Scand J Public Health. 2013;41(8):883-889. doi:10.1177/1403494813499653PubMedGoogle ScholarCrossref
20.
Preston  S, Heuveline  P, Guillot  M.  Demography: Measuring and Modeling Population Processes. Oxford, United Kingdom: Blackwell Publisher; 2000.
21.
Chiang  CL.  Life Table and Its Applications. Malabar: Robert E. Krieger Publishing; 1984.
22.
Arriaga  EE.  Measuring and explaining the change in life expectancies.  Demography. 1984;21(1):83-96. doi:10.2307/2061029PubMedGoogle ScholarCrossref
23.
Arriaga  EE. Changing trends in mortality decline during the last decades. In Ruzicka L, Wunsch G, Kane P, eds.  Differential Mortality: Methodological Issues and Biosocial Factors. Oxford, England: Clarendon Press; 1989:105-129.
24.
Auger  N, Feuillet  P, Martel  S, Lo  E, Barry  AD, Harper  S.  Mortality inequality in populations with equal life expectancy: Arriaga's decomposition method in SAS, Stata, and Excel.  Ann Epidemiol. 2014;24(8):575-580.e1. doi:10.1016/j.annepidem.2014.05.006Google ScholarCrossref
25.
GBD 2017 Risk Factor Collaborators.  Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017.  Lancet. 2018;392(10159):1923-1994. doi:10.1016/S0140-6736(18)32225-6PubMedGoogle ScholarCrossref
26.
Long  JS, Freese  J.  Regression Models for Categorical Dependent Variables Using Stata. College Station, TX: Stata Press; 2006.
27.
Gerdtham  U-G, Johannesson  M.  Absolute income, relative income, income inequality, and mortality.  J Hum Resour. 2004;39(1):228-247. doi:10.2307/3559011Google ScholarCrossref
28.
International Comparison Program (ICP) 2011. http://www.worldbank.org/en/programs/icp#5. Accessed March 5, 2019.
29.
Lund  K, Lund  M, Bryhni  A.  Tobacco consumption among men and women 1927-2007  [article in Norwegian].  Tidssk Nor Laegeforen. 2009;129(18):1871-1874.Google ScholarCrossref
30.
Schaap  MM, Kunst  AE, Leinsalu  M,  et al.  Female ever-smoking, education, emancipation and economic development in 19 European countries.  Soc Sci Med. 2009;68(7):1271-1278. doi:10.1016/j.socscimed.2009.01.007PubMedGoogle ScholarCrossref
31.
Williams  CC, Renooy  P.  Tackling Undeclared Work in 27 European Union Member States and Norway: Approaches and Measures Since 2008. Dublin, Ireland: Eurofound; 2013.
32.
Aaberge  R, Atkinson  A, Modalsli  J. IZA DP No. 7729: the ins and outs of top income mobility. Bonn, Germany: IZA Institute of Labor Economics; 2013. https://www.iza.org/publications/dp/7729/the-ins-and-outs-of-top-income-mobility.
33.
Kreiner  CT, Nielsen  TH, Serena  BL.  Role of income mobility for the measurement of inequality in life expectancy.  Proc Natl Acad Sci U S A. 2018;115(46):11754-11759. doi:10.1073/pnas.1811455115PubMedGoogle ScholarCrossref
34.
Aalen  O, Borgan  O, Gjessing  H.  Survival and Event History Analysis: A Process Point of View. Berlin, Germany: Springer Science & Business Media; 2008. doi:10.1007/978-0-387-68560-1
35.
Wolleswinkel Vanden Bosch  JH, VanPoppel  FWA, Mackenbach  JP.  Reclassifying causes of death to study the epidemiological transition in the Netherlands, 1875.  European Journal of Population-Revue Europeenne de Demographie. 1992;1996:12.Google Scholar
36.
Pedersen  AG, Ellingsen  CL.  Data quality in the Causes of Death Registry.  Tidsskr Nor Legeforen. 2015;135(8):768-770. doi:10.4045/tidsskr.14.1065Google ScholarCrossref
37.
Naess  O, Claussen  B, Thelle  DS, Smith  GD.  Four indicators of socioeconomic position: relative ranking across causes of death.  Scand J Public Health. 2005;33(3):215-221. doi:10.1080/14034940410019190PubMedGoogle ScholarCrossref
If you are not a JN Learning subscriber, you can either:
Subscribe to JN Learning for one year
Buy this activity
jn-learning_Modal_LoginSubscribe_Purchase
If you are not a JN Learning subscriber, you can either:
Subscribe to JN Learning for one year
Buy this activity
jn-learning_Modal_LoginSubscribe_Purchase
With a personal account, you can:
  • Access free activities and track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
Education Center Collection Sign In Modal Right

Name Your Search

Save Search
With a personal account, you can:
  • Track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
jn-learning_Modal_SaveSearch_NoAccess_Purchase

Lookup An Activity

or

My Saved Searches

You currently have no searches saved.

With a personal account, you can:
  • Access free activities and track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
Education Center Collection Sign In Modal Right
Topics
State Requirements