Significance of silent ischemia and microalbuminuria in predicting coronary events in asymptomatic patients with type 2 diabetes.
OBJECTIVE
The aim of this study was to investigate the relationships between future coronary heart disease (CHD) events and baseline silent myocardial ischemia (SMI) and microalbuminuria (MA) in subjects with type 2 diabetes (T2D) free from known CHD.


BACKGROUND
Coronary heart disease is often asymptomatic in subjects with diabetes. There is limited information on the prognostic value of SMI and MA in this group.


METHODS
Eighty-six patients with T2D and no history of CHD were studied (43 with MA individually matched with 43 normoalbuminuric patients; mean [SD] age 62 [+/-7] years, 62 men). Metabolic assessment, three timed overnight urine collections for albumin excretion rate, a treadmill exercise test and ankle brachial index (ABI) were performed at baseline. Patients were followed for 2.8 years.


RESULTS
Forty-five (52%) patients had SMI during treadmill testing. At review, there had been 23 coronary (CHD) events in 15 patients. Univariate Cox regression analysis showed that CHD events were significantly related to baseline ABI (p = 0.014), SMI (p = 0.020), MA (p = 0.046), 10-year Framingham CHD risk >30% (p = 0.035) and fibrinogen (p = 0.026). In multivariate analysis, SMI was the strongest independent predictor of CHD events (p = 0.008); risk ratio (95% confidence interval) for SMI: 21 (2 to 204). In the prediction of CHD events, SMI showed higher sensitivity and positive predictive value than MA or Framingham calculated CHD risk.


CONCLUSIONS
The presence of baseline SMI and MA are associated with future CHD events in asymptomatic patients with T2D and may be of practical use in risk stratification.
Rutter
Martin K
MK
Department of Medicine, University of Newcastle upon Tyne, Newcastle upon Tyne, United Kingdom. Martin.K.Rutter@btinternet.com
Wahid
Shahid T
ST
McComb
Janet M
JM
Marshall
Sally M
SM
D000419:Albuminuria / Q000453:epidemiology*; D016022:Case-Control Studies; D003327:Coronary Disease / Q000453:epidemiology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000453:epidemiology*; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013997:Time Factors