Age and Ageing Advance Access originally published online on May 5, 2006
Age and Ageing 2006 35(5):463-468; doi:10.1093/ageing/afl019
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Review |
Mortality in people diagnosed with type 2 diabetes at an older age: a systematic review
1 Section of Public Health, Division of Community Health Sciences, University of Dundee, The Mackenzie Building, Kirsty Semple Way, Dundee DD2 4BF, UK
2 Division of Medicine and Therapeutics, University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK
3 School of Medicine, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK
Address correspondence to: Karen N. Barnett. Tel: (+44) 1382 420076. Fax: (+44) 1382 420101. Email: k.barnett{at}chs.dundee.ac.uk
Objectives: to review all published observational studies reporting on all-cause mortality in patients with type 2 diabetes to determine the degree of increased mortality when diagnosed at an older age.
Design: systematic literature search.
Setting: the review included studies carried out in populations from Germany, United Kingdom, United States, Japan, Italy, Western Australia, Netherlands and Sweden.
Measurements: Medline, CINAHL, EMBASE, National Research Register and Cochrane Reviews were systematically searched from 1975 to 2004. We identified observational studies that reported overall mortality for people diagnosed with type 2 diabetes when they were over the age of 60, compared with a non-diabetic population. Outcome measures were expressed as risk ratios or relative risks.
Results: among 14 eligible studies, one study reported reduced mortality for patients diagnosed with type 2 diabetes over the age of 60, whereas another found virtually no increased risk of mortality. However, 7 of the 14 studies reported increased mortality in all patients diagnosed when older, and 5 studies for certain subgroups only. A meta-analysis showed the combined relative risks (with 95% CI) of increased mortality for men diagnosed between the ages of 60 and 70 to be 1.38 (1.081.76) and 1.13 (0.881.45) for men diagnosed aged 70 years or older. A similar pattern was found for the same age groups for women, with combined relative risks of 1.40 (1.101.79) and 1.19 (0.931.52) respectively.
Conclusion: increased mortality associated with a diagnosis of type 2 diabetes at an older age is lower than that reported for the general older diabetic population.
Keywords: type 2 diabetes, mortality, older people
Received September 6, 2005; accepted in revised form March 7, 2006.