This study aimed to validate a proposed systemic risk spectrum for predicting foot complications in type 2 diabetes patients. The risk spectrum included five constructs: macrovascular disease, microvascular disease, functional microvascular disease, metabolic syndrome, and family history. The study reviewed medical charts of type 2 diabetes patients and found a significant but weak correlation between the sum of risk constructs and total complications. Regression models showed the risk spectrum sum modestly predicted developing complications, explaining only 1.9-2.3% of variance. While validating the proposed spectrum, the study found it modestly predicted complications.

1. Introduction
For a diabetic patient, there is a significantly greater risk of
developing ulcers, infections, and amputations in comparison
to non-diabetics. The probability for the occurrence of a
complication is predicted under a voluminous sum of different
clinical and social risk factors. Risk factors including systemic
pathology, local vascular disease, and social and family history
have been linked to diabetic foot complications. However,
only risk stratification models based on local pathology have
been validated. While a risk spectrum based on systemic
disease has been proposed, it has never been validated. The
systemic risk spectrum has the following five constructs:
macrovascular disease, microvascular disease, functional
microvascular disease, metabolic syndrome, and family history.
[Harkless, 2004]
The goal of this study is to validate the constructs and overall
risk spectrum score to help develop a model that predicts the
development of foot related complications of Type II diabetes
mellitus. This can potentially help focus efforts on those
patients in need of he greatest preventive care to optimize
their health and decrease the cost to the health system
Materials and methods
This retrospective study was based on medical chart review. Of
all Type II diabetic patients over the age of 18 who were seen
at the Western University of Health Sciences Foot & Ankle
Center between January 2011 and April 2014. The patient
demographics were recorded at the initial encounter and the
medical and surgical history, diabetes pharmaceutical
management, and any foot related complications were
recorded at each visit. at the Center was recorded. The
prevalence of all history and complications was determined.
The presence of each category of the risk spectrum was
identified and the risk spectrum sum was calculated.
Using SPSS statistical software the following tests were
performed:
• Correlations for each construct of the risk spectrum and the
development of any complication
• Log regression model for the sum of the risk spectrum and
the development of any complication
• Linear regression model for the sum of the risk spectrum
and the total number of complications developed
Acknowledgments
I would like to thank Dr. Labovitz for his mentorship and guidance
throughout this project. I would like to thank Dr. Shofler assisting
in the calculation of the data.
Results
Discussions:
Using a linear regression model, we determined that there is a
weak positive correlation, albeit significant, between the sum of
the constructs and the total number of complications. A log
regression model determined a significant relationship with a
stronger correlation for the sum of the risk spectrum constructs
predictive of developing any complication. The goodness-to-fit
tests show the model is predictive of the development of any
complications. The predictive models show only 2.3% of the
variance is due to the sum of the spectrum when predicting any
complication occurring and only 1.9% of the variance for the
total number of complications developed. The risk spectrum
score predicts a 16.3% increased chance of developing another
complication and with each increase of the score a patient is a
1.35 times more likely to develop a complication.
Briesaun Williams1, Jonathan Labovitz, DPM2, David Shofler, DPM2
1. Western University of Health Sciences, Graduate College of Biomedical Sciences, Pomona, CA
2. Western University of Health Sciences, College of Podiatry, Pomona, CA
Literature cited
1, Harkless L and Holmes C. Linking Risk Factors: The Role of
History in Predicting Outcome. The Diabetic Foot 2004; 7(3):
114-122.
2. Peters EJG, Lavery LA. Effectiveness of the DIabetic Foot Risk
Classification System of the International Working Group on
the Diabetic Foot. 2001, 24:1142 1447.
3. Reiber GE, Pecoraro RE, Koepsell TD (1992) Risk factors for
amputation in patients with diabetes mellitus. A case-control
study. Annals of Internal Medicine. 117(2): 97–105
4. Armstrong DG, Lavery LA, Harkless LB, Van Houtum WH (1997)
Amputation and reamputation of the diabetic foot. Journal of
the American Podiatric Medical Association 87: 255–59
5. Flores AR. Risk Factors for Amputation in Diabetic Patients: A
Case-control Study. Archives of Medical Research. January 14
1998; Volume 29, No.2.
6. Marso SP, Hiatt WR. Peripheral Arterial Disease in Patients with
Diabetes. Journal American College of Cardiology 2006, 47(5):
Further information
Due to the high percentage of other possible variables, it is possible to look
into other factors that were not observed in this study as other direct
correlations.
Diabetic Risk Spectrum and Its Prevalence of
Complication
Construct Pathology
Macrovascular disease Peripheral arterial disease, Heart disease, CVA, CAD,
Microvascular disease Neuropathy, Retinopathy, Nephropathy, Renal disease
Functional microvascular disease Gastroparesis, Impotence
Metabolic syndrome disease HTN, Obesity,
Family history disease Family history DM, Family history amputation
The Systemic Risk Spectrum