Heart rate-corrected QT interval prolongation as a prognostic marker for 3-year survival in people with Type 2 diabetes undergoing above-ankle amputation.
OBJECTIVE
To evaluate whether heart rate-corrected QT interval is a plausible prognostic factor for survival after major amputation in people with Type 2 diabetes.


METHODS
All people with Type 2 diabetes aged < 80 years who underwent a major amputation at two hospitals with multidisciplinary diabetic foot teams were evaluated and grouped according to whether their heart rate-corrected QT interval was  ≤  or  > 440 ms.


RESULTS
A total of 70 patients with a median age of 72 years were included in the study. During the 3 years of follow-up, 38 patients (54%) died. Heart rate-corrected QT interval prolongation was present in 51.4% of the patients and was strongly associated with 3-year mortality (73 vs 36%; P < 0.001). In a Cox proportional hazard model, heart rate-corrected QT interval prolongation was the strongest independent risk factor for 3-year mortality [hazard ratio 2.20 (95% CI 1.11-4.38)]. Treatment with metformin seemed to have a protective effect [hazard ratio 0.22 (95% CI 0.05-0.94)].


CONCLUSIONS
The findings of the present study indicate that heart rate-corrected QT interval prolongation is associated with increased mortality in people with Type 2 diabetes undergoing above-ankle amputation.
Clinical Sciences in Lund, Lund University, Lund, Sweden; Department of Endocrinology, Skåne University Hospital, Ängelholm, Sweden.
K
K
Fagher
A
A
Nilsson
M
M
Löndahl
D000368:Aged; D000671:Amputation, Surgical; D000842:Ankle / Q000601:surgery*; D015415:Biomarkers / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000401:mortality* / Q000503:physiopathology; D017719:Diabetic Foot / Q000209:etiology / Q000601:surgery*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000378:metabolism; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome
D015415:Biomarkers; D006442:Glycated Hemoglobin