BACKGROUND/RATIONALE:
Despite the societal and personal impact of amputations in persons with diabetes, research in this area has been extremely limited, and has not resulted in a definitive analysis that can demonstrate that amputation rates among VHA clinical users of VHA care have decreased. Challenges to doing so include definition of cohorts, risk adjustment, ascertainment of amputation and characterization of amputation.

OBJECTIVE(S):
Aim 1. Analyze incident non-traumatic LEAs among VHA clinical users with diabetes using multiple years of the matched VHA and Medicare data.
Aim 2. Analyze longitudinal trends in risk adjusted incident annual amputations among VHA clinical users with diabetes.
Aim 3. Analyze risk of and time to repeat amputations and medical outcomes (stroke, dialysis, and death) among diabetic veterans identified with incident LEAs during study the period.
Aim 4. Evaluate the association between initial non-traumatic major amputation and the use of lower extremity bypass surgery and angioplasty by diabetic VA clinical users.

METHODS:
The basic design of the study was a retrospective inception cohort. Under this approach, inception cohorts were identified with data from FY 1999 (10/1/1998) through FY 2003 (9/30/2003) and followed through the end of FY 2004 (9/30/2004). Because the inception cohort was identified from FY 1999 through FY 2003, the follow up period of VHA clinical users varied from a minimum of 1 year to a maximum of 5 years.


FINDINGS/RESULTS:
1. Initial Lower Extremity Amputations (ILEAs): Compared with any amputations in fiscal year 2000, 12-, 18-, and 24-month look-back period decreased the ILEA rates by 19%, 24%, and 27%, respectively. The extent of identification was most complete with 24 months prior data, with marginal gains in extending the prior observation period from 18 to 24 months. (Sambamoorthi et al, 2006).
2. Regional Variation in Amputations: Simultaneous evaluation of major and minor amputation rates identifies different patterns of regional outlier status compared to total or major amputation rates alone. This strategy may facilitate targeted evaluations of health-care processes and structures (Tseng et al, 2007a).
3. Individual Level Predictors Of Amputations: After controlling for other independent variables, a five-point increase in MCS score was associated with a 5% decrease in the risk of major lower extremity amputations (LEAs) (odds ratio [OR]=0.95; 95% confidence interval [95% CI]=[0.94, 0.96]) but was not related to minor LEAs (OR=1.01; 95% CI=[0.97, 1.05]). (Tseng et al, 2007b).


IMPACT:
Our findings are highly relevant to VA and non-VA policy-makers. A strong association was found between continuity of foot care surveillance and improved mental health functioning and decreased major amputations, consistent with the mission of the VA Prevention, Amputation Care and Treatment Program.

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External Links for this Project

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PUBLICATIONS:

None at this time.

DRA: Health Systems Science
DRE: Epidemiology
Keywords: Diabetes, Practice patterns, Utilization patterns
MeSH Terms: none