Amputation and cardiac comorbidity: analysis of severity of cardiac risk.
OBJECTIVE
To evaluate population-based cardiovascular risk scores and coronary artery calcification scores (CACS) in amputees.


METHODS
A retrospective cohort study of 1300 veterans in a cardiac computed tomography database.


METHODS
1B Veterans Administration medical center.


METHODS
A total of 76 amputees and similar number of age-, gender-, and Framingham Risk Scores (FRS)-matched control subjects.


METHODS
The amputee population was identified and compared for CACS and traditional cardiac risk factors. Two control groups were used: control group 1, with known risk factors including diabetes mellitus, and control group 2, with all risk factors without diabetes mellitus.


METHODS
Statistical associations between amputee and control group FRS scores, CACS, and other cardiac risk factors were assessed.


RESULTS
The study included 57 nontraumatic and 19 traumatic amputees with an average age of 62.4 years. Sixty-six amputees were in the low-to-intermediate cardiac risk groups according to FRS. Despite this classification, the mean CACS were significantly higher in amputees (1285 ± 18) than in either of the control groups: control group 1 (540 ± 84) and control group 2 (481 ± 11), P < .001. CACS also were significantly higher in the nontraumatic subject group (1595 ± 12) compared with the traumatic group (356 ± 57; P < .001). Upon categorization of CACS based on probability of coronary artery disease (CAD), 76% of amputees had a CACS >100 and 38% of amputees had a CACS >1000. Interestingly, CACS were almost the same in finger/toe amputations compared with an above-knee amputation, indicating an already ongoing CAD process irrespective of level of amputation. The predominant clinical significant cardiac risk factors in amputees are hypertension (89.5%), P < .005; chronic kidney disease (31.6%), P < .001; dyslipidemia (72.4%), P < .04; and insulin resistance. Total cholesterol, low-density lipoprotein, and high-density lipoprotein levels were nonsignificantly low in all amputees. Triglycerides were particularly higher in traumatic patients compared with nontraumatic patients, with the triglycerides/high-density lipoprotein ratio >7.


CONCLUSIONS
This study demonstrates that amputees have a much greater burden of underlying atherosclerotic disease as detected by CACS than do control subjects matched by Framingham risk stratification. Early screening for CAD and aggressive targeted interventions may be an important part of management to reduce early mortality after amputation.
Department of Physical Medicine & Rehabilitation, Loma Linda University Medical Center, Loma Linda, CA 92354, USA. drmallik@yahoo.com
Mallikarjuna
M
Nallegowda
Esther
E
Lee
Murray
M
Brandstater
Alloysius B
AB
Kartono
Guresh
G
Kumar
Gary P
GP
Foster
D000674:Amputees; D016022:Case-Control Studies; D015331:Cohort Studies; D015897:Comorbidity; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000453:epidemiology*; D050171:Dyslipidemias / Q000453:epidemiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D007333:Insulin Resistance; D007674:Kidney Diseases / Q000453:epidemiology; D008075:Lipoproteins, HDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D014280:Triglycerides / Q000097:blood
D008075:Lipoproteins, HDL; D014280:Triglycerides