RESULTS OF SELFMONITORING ON GLUCOMETER SYSTEMS ADVANCE AND OPTIUM IN DAILY ROUTINE

The aim of this prospective clinical study was to compare the results of B-glucose estimations performed simultaneously on glucometer Advance (with Micro-draw strips) and Optium (G3 strips) by lay healthy volunteers under non-standardized conditions of everyday life, to assess the difficulties dealing with lay-handling of these systems and to demonstrate the possibilities of the software Glucobalance (Hypoguard) and PC-Link (Medisense/Abbott) for the analysis of selfmonitoring. In the course of 5 days, a total of 721 pairs of measurements were carried out on 10 pairs of glucometer Advance and Optium by 10 healthy volunteers aged 16-40 years. The data transfer of all values into computer from glucometer Advance using the Glucobalance software and from glucometer Optium using the PC-Link was carried out to determine the results. The correlation of B-glucose measured on the glucometer Advance and Optium was strong (r = 0.73). Glucometer Advance brings values about 0.21 +/- 0.06 mmol/l lower than glucometer Optium. The average difference found within each pairs of glucometers Advance - Optium varied. Nevertheless, these differences are acceptable for routine selfmonitoring. The handling of glucometer Advance is not difficult for lay persons. The Glucobalance software simplifies the result evaluation by each tested person. Even though there are some advantages in comparison with the PC-Link, it should be further developed.


INTRODUCTION
Blood glucose selfmonitoring has become a prerequisite in the successful treatment of both type 1 and type 2 diabetes mellitus 3,4,13,15,22 .In this regard different types of glucometers are marketed to cover increasing demands 11,24 .The Glucometer Advance (Hypoguard, Great Britain) and the recently developed new generation of capillary strips (Micro-draw) comprise an approved B-glucose selfmonitoring system (GSS) which is ready to use in many countries.Glucometer Optium (Medisense/Abbott) and G 3 strips are already known to produce acceptable results from several years experience 14 .
The aim of this prospective clinical study was: 1. to compare the results of B-glucose estimations performed simultaneously on glucometer Advance (with Micro-draw strips) and Optium (G3 strips) by lay healthy volunteers under the non-standardized conditions of everyday life; 2. to assess the difficulties dealing with lay -handling of these systems; 3. to demonstrate the possibilities of the software Glucobalance (Hypoguard) and PC-Link (Medisense/Abbott) for the analysis of selfmonitoring.

Tested persons
Ten healthy volunteers aged between16 and 40 years (students, nurses, laboratory assistants) having no personal experience with GSS Advance or Optium entered the study.Informed consent was obtained from all of them.Everyone received one glucometer Advance, one glucometer Optium and two packages of strips per glucometer (Table 1).All volunteers were given a 30 min training in selfmonitoring.None of the glucometers with the exception of Optium No 6 had been used before.

Study design
All measurements were performed in July 2003 in the course of one week, usually at home, at work, in a hospi-tal ward or on a trip.The weather conditions were good, temperatures mostly in between 15-30 °C.
Each volunteer was encouraged to perform B-glucose selfmonitoring at breakfast and at dinner, according to the following 7-point schedule: before the meal (time 0) and 15, 30, 45, 60, 90 and 120 min following the start of the meal.In this way, everyone was performing 14 estimations per day.
In selfmonitoring, capillary blood was obtained from a finger by means of a lancing device; the first drop was put on a strip G3 (Optium) and, immediately afterwards, the second drop was put on a Micro-draw strip (Advance).The volunteer registered all results read on the displays of both glucometers in the protocol.
At the end of the one-week test period each volunteer was asked to describe the positive and the negative features of individual tested systems.

Statistical analysis
The data were transferred by means of respective software (Glucobalance or PC-Link) from the glucometers to a PC.
The program MS Excel and the statistical package SPSS, v. 10.1, were used for analyzing the results: t-test for matched observations, Correlation Analyses a Analyses of Variance were applied to evaluate the data.The level of significance p < 0.05 was taken.

RESULTS
In the course of 5 days, a total of 721 pairs of measurements were carried out on 10 pairs of gluco meter Advance and Optium by 10 volunteers.One measurement showed an extreme BG value of 42.8 mmo/l; as this value exceeded the declared range of glucometer (1.1-33.3mmol/l), the pair concerned was not considered for statistical analysis.
For the results of measurements from individual glucometers see Table 2. Occasionally there were some high (>14.0mmol/l) or low (<3.3 mmol/l) B-glucose values measured on both glucometers Advance and Optium.There is no explanation for these unusual values.
There was a strong correlation between the B-glucose values measured on all glucometers Advance and Optium (r = 0.73, see Fig. 1).However, the correlation coefficients of the individual pairs of glucometers differed (r = 0.58 to r = 0.91, see Table 3).
For the frequency of B-glucose differences in all 10 pairs of glucometers (Advance -Optium) see the histogram in Fig. 2. The majority of all differences (96,1 %) was within ± 2.25 mmol/l.Extreme differences were registered only rarely (Table 4).
For the results of statistical analysis see Table 5: the B-glucose values on the Advance glucometers were lower about 0.21 ± 0.06 mmol/l (x ± SE), i.e. 2.998 %, than the values measured on the glucometer Optium.This difference did not depend on the absolute B-glucose concentration (Fig. 3).The results of analysis of variance of the differences of each glucometer is shown in Table 6: mean B-glucose differences within individual pairs of glucometers are often significantly different.
The volunteers agreed that the usage of both types of glucometers was simple.The glucometer Advance was appreciated for its small, handy size, the option of going through the memory results forwards and backwards and the very small amount of blood needed for one measurement.On the other hand, the large strip packages didn't fit into the box together with the glucometer and this was seen as a disadvantage.
The data transfer of all values into computer from glucometer Advance using the Glucobalance software and from glucometer Optium using the PC-link was carried out by a professional.The Glucobalance and PC-link enabled as to see the results of an individual volunteer separately.One of the advantages of the Glucobalance is the ability to edit histograms (Fig. 4), pie charts (Fig. 5) and statistics (Fig. 6) for individually set day time periods.The modal day (Fig. 7) and time trends (Fig. 8) are similar to those of the PC Link.None of the programs enables to compare the data interindividually.None of the programs comes in a Czech version.

Table 1 .
Characteristics of tested glucometer systems Advance and Optium

Table 2 .
Results of measurements from individual pairs of glucometers Advance (A) and Optium (O)

Table 3 .
Correlations between the B-glucose values measured on individual pairs of glucometers Advance (A) -Optium (O)

Table 4 .
Frequency table: B-glucose difference Advance -Optium Results of selfmonitoring on glucometer systems Advance and Optium in daily routine

Table 5 .
Statistical evaluation of the B-glucose difference Advance -Optium (all results)

Table 6 .
Statistical evaluation of the B-glucose difference Advance -Optium (ANOVA -multiple comparisons of individual patients i.e. pairs of glucometers)