Method of measuring stable hemoglobin A1c and measurement device therefor
A method of measuring stable hemoglobin A1c by a hemoglobin separation analysis method based on cation exchange, the method comprising: obtaining an analysis signal from a blood specimen to be measured by the separation analysis method; determining a C value, which is a peak value of a stable hemoglobin A1c peak, and an X value, which is a peak value of a specific peak appearing between the stable hemoglobin A1c peak and a hemoglobin A0 peak, from the analysis signal; and correcting the C value by applying the C value and the X value to a predetermined arithmetic expression to obtain a C′ value that is a reduced value from the C value, wherein the arithmetic expression is determined based on a correlation between a C value and an X value obtained from a blood specimen in which a stable hemoglobin A1c value is known by the separation analysis method.
1 . A method of measuring stable hemoglobin A1c comprising:
performing a hemoglobin separation analysis method based on cation exchange as a principle on a target blood specimen to obtain an analysis signal;
determining a C value, which is a peak value of a stable hemoglobin A1c peak, and an X value, which is a peak value of a specific peak appearing between the stable hemoglobin A1c peak and a hemoglobin A0 peak, from the analysis signal; and
correcting the C value by applying the C value and the X value to a predetermined arithmetic expression to obtain a C′ value that is a reduced value from the C value,
wherein the arithmetic expression is determined based on a correlation between a C value and an X value obtained from a reference blood specimen having a known stable hemoglobin A1c value by the separation analysis method.
2 . The method of measuring stable hemoglobin A1c according to claim 1 , wherein:
the arithmetic expression includes an expression represented by
Y=A×X
and
C′=C−Y,
wherein
A is a slope of a regression line between the X value and the C value, both of which are obtained from a plurality of reference blood specimens each having a known stable hemoglobin A1c value,
X is the X value obtained from the target blood specimen, and
C is the C value obtained from the target blood specimen.
3 . The method of measuring stable hemoglobin A1c according to claim 2 , wherein when a peak top detection time of the stable hemoglobin A1c peak is 0 and a peak top detection time of the hemoglobin A0 peak is 1, a peak appearing in a detection time of 0.1 or more and less than 0.65 is referred to as the specific peak.
4 . The method of measuring stable hemoglobin A1c according to claim 2 , wherein the correcting is executed in a case in which the X value exceeds a threshold value.
5 . The method of measuring stable hemoglobin A1c according to claim 1 , wherein:
the arithmetic expression includes an expression represented by
R 1 =a×X+b
and
C′=C−C×R 1 ,
wherein
a is a slope of a regression line between the X value and a temporal variation rate of the C value, both of which are obtained from a plurality of reference blood specimens each having a known stable hemoglobin A1c value,
b is an intercept of the regression line,
X is the X value obtained from the target blood specimen, and
C is the C value obtained from the target blood specimen.
6 . The method of measuring stable hemoglobin A1c according to claim 3 , wherein, providing when a peak top detection time of the stable hemoglobin A1c peak is 0 and a peak top detection time of the hemoglobin A0 peak is 1, a peak appearing in a detection time of 0.1 or more and less than 0.65 is referred to as the specific peak.
7 . The method of measuring stable hemoglobin A1c according to claim 5 , wherein the correcting is executed in a case in which the X value exceeds a threshold value.
8 . The method of measuring stable hemoglobin A1c according to claim 1 , wherein when a peak top detection time of the stable hemoglobin A1c peak is 0 and a peak top detection time of the hemoglobin A0 peak is 1, a peak appearing in a detection time of 0.1 or more and less than 0.65 is referred to as the specific peak.
9 . The method of measuring stable hemoglobin A1c according to claim 1 , wherein the correcting is executed in a case in which the X value exceeds a threshold value.
10 . A measurement device for stable hemoglobin A1c, comprising:
a memory that stores an arithmetic expression determined in advance based on a correlation between a C value, which is a peak value of a stable hemoglobin A1c peak, and an X value, which is a peak value of a specific peak appearing between the stable hemoglobin A1c peak and a hemoglobin A0 peak, by subjecting a reference blood specimen having a known stable hemoglobin A1c value to a hemoglobin separation analysis method based on cation exchange as a principle;
an analyzer that obtains an analysis signal by subjecting a target blood specimen to be measured to the hemoglobin separation analysis method based on cation exchange as a principle;
a first calculator that obtains a C value, which is a peak value of the stable hemoglobin A1c peak, and an X value, which is a peak value of a specific peak appearing between the stable hemoglobin A1c peak and the hemoglobin A0 peak, from the analysis signal; and
a second calculator that calculates a C′ value that is a reduced value from the C value, by applying the C value and the X value to the arithmetic expression.
11 . The measurement device according to claim 10 , wherein:
the arithmetic expression includes an expression represented by
Y=A×X
and
C′=C−Y,
wherein
A is a slope of a regression line between the X value and the C value, both of which are obtained from a plurality of reference blood specimens each having a known stable hemoglobin A1c value,
X is the X value obtained from the target blood specimen, and
C is the C value obtained from the target blood specimen.
12 . The measurement device according to claim 11 , wherein when a peak top detection time of the stable hemoglobin A1c peak is 0 and a peak top detection time of the hemoglobin A0 peak is 1, a peak appearing in a detection time of 0.1 or more and less than 0.65 is referred to as the specific peak.
13 . The measurement device according to claim 11 , wherein the second calculator calculates a C′ value in a case in which the X value exceeds a threshold value.
14 . The measurement device according to claim 10 , wherein:
the arithmetic expression includes an expression represented by
R 1 =a×X+b
and
C′=C−C×R 1 ,
wherein
a is a slope of a regression line between the X value and a temporal variation rate of the C value, both of which are obtained from a plurality of reference blood specimens each having a known stable hemoglobin A1c value,
b is an intercept of the regression line,
X is the X value obtained from the target blood specimen, and
C is the C value obtained from the target blood specimen.
15 . The measurement device according to claim 14 , wherein when a peak top detection time of the stable hemoglobin A1c peak is 0 and a peak top detection time of the hemoglobin A0 peak is 1, a peak appearing in a detection time of 0.1 or more and less than 0.65 is referred to as the specific peak.
16 . The measurement device according to claim 14 , wherein the second calculator calculates a C′ value in a case in which the X value exceeds a threshold value.
17 . The measurement device according to claim 10 , wherein when a peak top detection time of the stable hemoglobin A1c peak is 0 and a peak top detection time of the hemoglobin A0 peak is 1, a peak appearing in a detection time of 0.1 or more and less than 0.65 is referred to as the specific peak.
18 . The measurement device according to claim 10 , wherein the second calculator calculates a C′ value in a case in which the X value exceeds a threshold value.