Method of screening for disorders of glucose metabolism

• US 20040142403A1
• Filed: 11/05/2003
• Published: 07/22/2004
• Est. Priority Date: 08/13/2001
• Status: Abandoned Application

• Current Assignee: Sensys Medical, Inc. (Sensys Medical Limited)
• Original Assignee: Sensys Medical, Inc. (Sensys Medical Limited)
• Inventors: Ruchti, Timothy L., Hockersmith, Linda, Monfre, Stephen L., Hazen, Kevin H., Blank, Thomas B., Cone, Andrew, Hetzel, Donald
• Application Number:
  US10/702,236
• Publication Number:
  US 20040142403A1
• Time in Patent Office: Days
• US Class Current: 435/14
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: C12Q 1/54 involving glucose or galactose
• CPC Class Codes: G01N 2800/042 Disorders of carbohydrate metabolism, e.g. diabetes, glucose metabolism
• CPC Class Codes: G01N 33/66 involving blood sugars, e.g. galactose
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 50/70 for mining of medical data, e.g. analysing previous cases of other patients
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

A method of screening for disorders of glucose metabolism such as impaired glucose tolerance and diabetes allows prevention, or early detection and treatment of diabetic complications such as cardiovascular disease, retinopathy, and other disorders of the major organs and systems. A mathematical algorithm evaluates the shape of a subject'"'"'s glucose profile and classifies the profile into one of several predefined clusters, each cluster corresponding either to a normal condition or one of several abnormal conditions. The series of blood glucose values making up the glucose tolerance curve may be measured using any glucose analyzer including: invasive, minimally invasive and noninvasive types. The method is executed on a processing device programmed to perform the steps of the method. Depending on the outcome of the screening, a subject may be provided with additional information concerning their condition and/or counseled to consult further with their health care provider.

Claims

1. A method of screening a subject for disorders of glucose metabolism, comprising steps of:

measuring a glucose profile, said profile comprising a plurality of blood glucose concentrations from at least after a glucose or meal challenge;

using at least a portion of said plurality of blood glucose values, evaluating a shape of said profile according to at least one parameter of said profile; and

classifying said subject into at least one predetermined class based on evaluation of said shape.

2. The method of claim 1, wherein said plurality of blood glucose values comprises a time series.

3. The method of claim 1, wherein said blood glucose values are actual values.

4. The method of claim 1, wherein said blood glucose values are relative values.

5. The method of claim 1, wherein said parameters include any of:

initial fasting glucose concentration;

maximum glucose concentration;

glucose concentration after elapse of a predetermined time interval;

area under the curve of the glucose profile; and

area under the curve of the glucose profile over a defined period of time.

6. The method of claim 5, wherein said evaluating step comprises:

comparing any of said parameters with corresponding predetermined values and/or ranges of values indicative of either a normal condition or one of a plurality of abnormal conditions.

7. The method of claim 6, wherein said predetermined classes correspond to said conditions, said classes comprising:

normal;

impaired glucose tolerance; and

diabetic.

8. The method of claim 1, wherein said evaluation step comprises:

determining a weight for each of said parameters.

9. The method of claim 8, wherein said step of determining a weight comprises assigning each parameter a value on either a linear or non-linear scale, according to value of said parameter, said assigned value comprising said weight.

10. The method of claim 9, wherein minimum and maximum of said scale correspond to predetermined threshold values for a normal condition and a diabetic condition, respectively.

11. The method of claim 9, wherein minimum and maximum of said scale correspond to predetermined threshold values for a low glucose tolerance and a normal condition, respectively.

12. The method of claim 9, maximum of said scale corresponds to predetermined threshold values for a diabetic condition.

13. The method of claim 9, wherein ranges of values represented by said scale are established according to standard diagnostic criteria.

14. The method of claim 9, wherein missing parameters are assigned a weight of zero.

15. The method of claim 9, wherein missing data are supplied from historical data.

16. The method of claim 9, further comprising a step of calculating one or more screening factors based on actual or relative values of said parameters and said weights.

17. The method of claim 16, wherein said step of calculating screening factors comprises the step of calculating a weighted average of said weighted parameters according to:

18. The method of claim 16, wherein said step of calculating screening factors comprises the step of calculating a weighted average of said weighted parameters according to:

19. The method of claim 16, wherein said step of calculating screening factors comprises the step of calculating a weighted average of said weighted parameters according to:

20. The method of claim 16, wherein said step of calculating screening factors comprises steps of:

calculating a weighted average of a first set of selected weighted parameters according to;

${\mathrm{SF}}_4=\frac{\left(P_1<br><br>W_1+P_6<br><br>W_6\right)}{\left(W_1+W_6\right)},$

 

wherein SF₄=a first screening factor; and

calculating a weighted average of a second set of selected weighted parameters according to;

${\mathrm{SF}}_5=\frac{\left(P_2<br><br>W_2+P_3<br><br>W_3+P_4<br><br>W_4+P_5<br><br>W_5\right)}{\left(W_2+W_3+W_4+W_5\right)},$

 

wherein SF₅=a second screening factor.

21. The method of claim 16, further comprising a step of establishing threshold screening limits based on said screening factors.

22. The method of claim 1, wherein said parameters include any of:

initial fasting glucose concentration;

rate of increase of glucose concentration following said glucose challenge;

peak monitored glucose concentration;

duration glucose remains elevated;

rate of decrease of glucose concentration following said peak concentration;

minimum glucose concentration following said peak concentration;

area under the curve for the glucose profile; and

area under the curve during a subset in time of the glucose profile.

23. The method of claim 1, further comprising the step of advising said subject of screening results.

24. The method of claim 1, further comprising the step of advising said subject of health risks from complications likely to result from subject'"'"'s condition.

25. The method of claim 1, wherein said values are obtained using any of:

a noninvasive blood glucose analyzer;

a minimally invasive blood glucose analyzer; and

an invasive blood glucose analyzer.

26. The method of claim 1, wherein a processing device so programmed executes said steps.

27. The method of claim 1, wherein said profile comprises a plurality of blood glucose concentrations from before and after a glucose or meal challenge.