Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2010 Jan 12;182(1):E1-E17.
doi: 10.1503/cmaj.090495. Epub 2009 Dec 21.

Income-related differences in mortality among people with diabetes mellitus

Lorraine L Lipscombe  1 , Peter C Austin, Douglas G Manuel, Baiju R Shah, Janet E Hux, Gillian L Booth
Affiliations

Income-related differences in mortality among people with diabetes mellitus

Lorraine L Lipscombe et al. CMAJ. .

Abstract

Background: Mortality has declined substantially among people with diabetes mellitus over the last decade. Whether all income groups have benefited equally, however, is unclear. We examined the impact of income on mortality trends among people with diabetes.

Methods: In this population-based, retrospective cohort study, we compared changes in mortality from Apr. 1, 1994, to Mar. 31, 2005, by neighbourhood income strata among people with diabetes aged 30 years or more in the province of Ontario, Canada.

Results: Overall, the annual age- and sex-adjusted mortality declined, from 4.05% in 1994/95 (95% confidence interval [CI] 3.98%-4.11%) to 2.69% in 2005/06 (95% CI 2.66%-2.73%). The decrease was significantly greater in the highest income group (by 36%) than in the lowest income group (by 31%; p < 0.001). This trend was most pronounced in the younger group (age 30-64 years): the mortality rate ratio widened by more than 40% between the lowest and highest income groups, from 1.12 to 1.59 among women and from 1.14 to 1.60 among men. Income had a much smaller effect on mortality trends in the older group, whose drug costs are subsidized: the income-related difference rose by only 0.9% over the study period.

Interpretation: Mortality declined overall among people with diabetes from 1994 to 2005; however, the decrease was substantially greater in the highest income group than in the lowest, particularly among those aged 30-64 years. These findings illustrate the increasing impact of income on the health of people with diabetes even in a publicly funded health care setting. Further studies are needed to explore factors responsible for these income-related differences in mortality.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Age- and sex-standardized mortality by income quintile among people in Ontario aged 30 years or more with diabetes mellitus from 1994/95 to 2005/06.
Figure 2
Figure 2
Predicted mortality by income quintile among women with diabetes aged 30–64 years (top panel) and women aged 65 or more (bottom panel) from 1994/95 to 2005/06. (Trends were similar among men.)
Figure 3
Figure 3
Mortality rate ratios between the lowest and highest income quintile among women and men aged 30 years or more with diabetes from 1994/95 to 2005/06.
See this image and copyright information in PMC

References

    1. Lipscombe LL, Hux JE. Trends in diabetes prevalence, incidence, and mortality in Ontario, Canada 1995–2005: a population-based study. Lancet. 2007;369:750–6. - PubMed
    1. Wild S, Roglic G, Green A, et al. Global prevalence of diabetes: estimates for the year 2000 and projections for 2030. Diabetes Care. 2004;27:1047–53. - PubMed
    1. World Health Organization. Diabetes programme: facts and figures. Geneva (Switzerland): The Organization; 2008. [(accessed 2009 Oct. 20)]. Available: www.who.int/diabetes/facts/en/index.html.
    1. Booth GL, Kapral MK, Fung K, et al. Relation between age and cardiovascular disease in men and women with diabetes compared with non-diabetic people: a population-based retrospective cohort study. Lancet. 2006;368:29–36. - PubMed
    1. Gregg EW, Gu Q, Cheng YJ, et al. Mortality trends in men and women with diabetes, 1971 to 2000. Ann Intern Med. 2007;147:149–55. - PubMed

Publication types