SLR - July 2014 - Bindu Mathew
Statin Use and Lower Extremity Amputation Risk in Nonelderly Diabetic Patients
Reference: Sohn MW, Meadows JL, Oh EH, Budiman-Mak E, Lee TA, Stone NJ, Pearce WB. J Vasc Surg. 2013 Dec;58(6):1578-1585.
Scientific Literature Review
Reviewed By: Bindu Mathew, DPM
Residency Program: Pinnacle Health System
Podiatric Relevance: Foot ulceration and amputation risk in diabetic patients is something that podiatrists encounter on a recurrent basis. Therefore, it is beneficial to educate ourselves on the risks, treatments and clinical evidence based therapies to minimize the risk of lower extremity amputations. Studies have shown that low-density lipoprotein cholesterol (LDL-C) lowering therapy reduces cardiovascular risk in diabetics, but its outcomes on vascular health have not been studied. The authors aimed to examine the effects between cholesterol lowering medications (statin and nonstatin) and risk of major lower extremity amputations (LEA).
Methods: This was a retrospective cohort study of patients under the age of 65 with Type 1 and 2 diabetes mellitus who were not taking cholesterol lowering medications at baseline. Patients at the US Veterans Affairs Healthcare were followed for five years in 90 day intervals between 2004 and 2008. The use of cholesterol-lowering therapies, diabetic medications, hemoglobin A1C, and vital signs were recorded in each period. Major risk factors of LEA such as peripheral neuropathy, peripheral artery disease, and foot ulcers were observed at baseline and updated. Hazard ratios were estimated for LEA and deaths.
Results: Researchers found that 217 (0.3 percent) of 83,953 patients who did not use any cholesterol using medications at baseline experienced a major LEA and 11,716 (14.0 percent) patients died during the five year follow-up. Statin users were 35-43 percent less likely to experience an LEA (HR, 0.65; 95 percent confidence interval [CI], 0.42-0.99) and treatment failure (HR, 0.57; 95 percent CI, 0.54-0.60) when compared to patients who did not use cholesterol-lowering agents. Users of other cholesterol-lowering medications were not significantly different in LEA risk but had a 41 percent lower risk of treatment failure.
Conclusions: This is the first study to report a significant association between statin use and decreased amputation risk among diabetic patients. For LEA risk, those given non-statins did not have a statistically significant benefit and its effect on LEA risk was much smaller compared with statins. It also showed that there are many patients that were not being treated with cholesterol lowering agents, indicating an area for clinical improvement.