New-onset diabetes and risk of all-cause and cardiovascular mortality: the Cardiovascular Health Study.
OBJECTIVE
Cardiovascular risk associated with new-onset diabetes is not well characterized. We hypothesized that risk of all-cause and cardiovascular mortality would be similar among participants with and without new-onset diabetes in the first years of follow-up and rise over time for new-onset diabetes.


METHODS
The Cardiovascular Health Study (CHS) is a longitudinal study of cardiovascular risk factors in adults aged > or =65 years. We used CHS participants to define a cohort (n = 282) with new-onset diabetes during 11 years of follow-up. New-onset diabetes was defined by initiation of antidiabetes medication or by fasting plasma glucose >125 mg/dl among CHS participants without diabetes at study entry. Three CHS participants without diabetes were matched for age, sex, and race to each participant with new-onset diabetes at the time of diabetes identification (n = 837). Survival analysis provided adjusted hazard ratios (HRs) for all-cause and cardiovascular mortality.


RESULTS
During a median of 5.9 years of follow-up, there were 352 deaths, of which 41% were cardiovascular. In adjusted analyses, new-onset diabetes was associated with an HR of 1.9 (95% CI 1.4-2.5) for all-cause and 2.2 (1.4-3.4) for cardiovascular mortality compared with no diabetes. Mortality risks were elevated within 2 years of onset, especially cardiovascular risk (4.3 [95% CI 1.7-10.8]), and did not increase over time.


CONCLUSIONS
Our findings indicate that there may be a mortality differential soon after diabetes onset in older adults and suggest that long-term macrovascular damage from atherosclerosis may not be primarily responsible for increased risk.
Smith
Nicholas L
NL
Cardiovascular Health Research Unit, 1730 Minor Ave., Suite 1360, Seattle, WA 98101, USA. nlsmith@u.washington.edu
Barzilay
Joshua I
JI
Kronmal
Richard
R
Lumley
Thomas
T
Enquobahrie
Daniel
D
Psaty
Bruce M
BM
D000368:Aged; D000369:Aged, 80 and over; D050197:Atherosclerosis / Q000401:mortality; D001786:Blood Glucose / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000401:mortality*; D048909:Diabetes Complications / Q000401:mortality*; D003920:Diabetes Mellitus / Q000097:blood / Q000175:diagnosis*; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D012307:Risk Factors; D015996:Survival Rate; D013997:Time Factors
D001786:Blood Glucose