Evaluation of Linearity and Interference Effect on SMBG and POCT Devices, Showing Drastic High Values, Low Values, or Error Messages.

BACKGROUND: When a patient with diabetes measures blood glucose levels using a simple blood glucose meter, an error message or abnormal value may be displayed because of interfering substances, potentially leading to unnecessary medical treatment. METHODS: Here, we tested 10 self-monitoring of blood glucose (SMBG) and point-of-care testing (POCT) devices to investigate under what conditions they fail to measure blood glucose levels or display abnormal values instead. We also evaluated the influence and linearity of several well-known interfering substances and hematocrit (Ht). Each adjusted sample was measured by each device twice and the values compared with the reference values. RESULTS: Linearity was favorable in all but one model. The impact of the interfering substances and Ht has been confirmed in many SMBG and POCT devices. In particular, some models showed significant pseudo-high or -low levels for samples that contained ascorbic acid, which is used widely in infusion solutions. Three devices showed error messages to avoid presenting a false value. CONCLUSIONS: Since pseudo-high levels may result in the excessive administration of insulin and lead to adverse events, this report serves as a critical reminder of the importance of device choice for specific indications. Three new devices have safety functions that prevent the showing of false values.

Increased cardiac mortality in women compared with men in patients with acute myocardial infarction.

OBJECTIVE: It has been reported that women with acute myocardial infarction (AMI) have a higher short-term mortality rate than men, but the reason is not known. The profile in relation to age, gender and risk factors was evaluated to compare AMI and unstable angina pectoris (UAP). METHODS: Findings from 984 patients including 580 patients with AMI (129 women, 451 men) and 404 patients with UAP (131 women, 273 men) were analyzed by the South Osaka Acute Coronary Syndrome Study Group (SACS). The primary endpoint of the study was in-hospital death. The primary endpoints of interest (cardiac death) were fatal recurrent myocardial infarction, death from congestive heart failure, and sudden death. RESULTS: Cardiac death during hospitalization within 30 days in AMI was higher in women than in men (12.4% vs 6.7%, p < 0.05). On the other hand, in UAP there was no significant difference between women and men (1.5% vs 0.7%, NS). The incidence of cardiac death in AMI was significantly higher for patients 75 years old and older (19.0%) than for patients less than 55 years old (4.2%), 55-64 years old (3.5%) and 65-74 years old (4.7%) (p < 0.001, respectively). CONCLUSIONS: Cardiac death was higher for women compared with men in patients with AMI. The worse prognosis for the AMI women patients was likely to be derived from less performance of percutaneous coronary intervention, and a high incidence of severe myocardial infarction. Further research should be focused on the analysis of various clinical backgrounds.