B-type natriuretic peptide can detect silent myocardial ischaemia in asymptomatic type 2 diabetes.

OBJECTIVE: To find out whether B-type natriuretic peptide (BNP) detects silent myocardial ischaemia in patients with type 2 diabetes, since many of these patients have silent ischaemia leading to unexpected cardiac deaths. DESIGN: Prospective cross-sectional study with consecutive recruitment of patients. SETTING: Outpatient, single centre. PATIENTS: 219 patients with type 2 diabetes. Patients were excluded if they had a history or evidence of cardiac failure. OUTCOME MEASURES: BNP, echocardiography and exercise tolerance test (ETT). BNP was compared with the ETT result in all patients and specifically in those who had no apparent ischaemic heart disease (IHD). RESULTS: 121 patients had no history of IHD or cardiac failure and of these patients 85 had a clearly abnormal or normal ETT result. BNP was higher in patients with an abnormal than with a normal ETT (mean 58.2 (SD 46.3) v 24.4 (SD 15.7) pg/ml, p < 0.001). In univariate analysis BNP was an independent predictor of an abnormal ETT (p < 0.001). In multivariate analysis BNP remained an independent predictor of the ETT result. BNP concentration over 20 pg/ml predicted an abnormal ETT result with a sensitivity of 87% and specificity of 37%, and BNP over 40 pg/ml had a sensitivity of 63% and a specificity of 81%. CONCLUSION: BNP is of value in predicting silent ischaemia on exercise testing in asymptomatic patients with type 2 diabetes.

Frequency and predictors of hypoglycaemia in Type 1 and insulin-treated Type 2 diabetes: a population-based study.

AIMS: To ascertain the frequency and identify predictors of self-reported hypoglycaemia in Type 1 and insulin-treated Type 2 diabetes. METHODS: A random sample of 267 people with insulin-treated diabetes were recruited from a population-based diabetes register in Tayside, Scotland. Each subject prospectively recorded the number of mild and severe hypoglycaemic episodes experienced over a 1-month period. Ordinal logistic regression was performed to identify potential predictors of hypoglycaemia. RESULTS: Five hundred and seventy-two hypoglycaemic events were reported by 155 patients. The participants with Type 1 diabetes had a total of 336 hypoglycaemic events with a rate of 42.89 events per patient per year. Of these, nine were severe hypoglycaemic events, with a rate of 1.15 events per patient per year. Participants with insulin-treated Type 2 diabetes experienced a total of 236 hypoglycaemic events with a rate of 16.37 events per patient per year. Of these, five were severe hypoglycaemic events, which would be equivalent to 0.35 events per patient per year. Predictors of hypoglycaemia in Type 1 diabetes were a history of previous hypoglycaemia (P = 0.006) and co-prescribing of any oral drug (P = 0.048). In patients with insulin-treated Type 2 diabetes, a history of previous hypoglycaemia (P < 0.0001) and duration of insulin treatment (P = 0.014) were significant predictors. CONCLUSION: The incidence of self-reported severe hypoglycaemia in insulin-treated Type 2 diabetes is lower than in Type 1 diabetes but does occur more often than previously reported and with sufficient frequency to cause significant morbidity. Duration of insulin treatment is a key predictor of hypoglycaemia in insulin-treated Type 2 diabetes.