Correct determination of body mass index in people with lower limb amputation

Transcription

1 December, Correct determation of body mass dex people with lower limb amputation Kitti Deé, Zsuzsanna Lelovics International Institute of Nutrition Pécs, Hungary Abstract Approximately 65 amputations can be expected for 100,000 habitants per year Hungary, 57 of them is lower limb amputation. The representation of peripheral vascular disease reached 80 90% of the causes of amputation Hungary and the developed countries at the end of the last century. The aim of the study was to determe the total body weight and the body mass dex (BMI) of amputees, methodology that can be used practice. We calculated the total body weight from measured or estimated body weight and body height, and determed BMI that is needed to (nutritional) rehabilitation. Adult lower limb amputees took part the survey. Calculation of BMI from measured body weight and body height without correction is often an correctly applied method the practice. Authors represent the distortg results of this correct practice 49 (31 males and 18 females) unilateral amputees and 10 (8 male and 2 female) both legs (femur) amputees. In the absence of both lower limbs estimation of the body height from the length of the ulna is a reliable method. Accordg to the BMI values calculated from the origal data only one third of these patients belonged to the optimal category and one third have BMI Considerg the weight of the missg limb 45 patients belonged to other category. Authors are aware of the limited usability of BMI (especially regardg people older 65), however, draw attention to the correct classification that results form false route use and the opportunities for practical use. Key words: amputation, body weight, corrected body mass dex I. BACKGROUND Lower limb arterial obstruction is a potential disease. Accordg to ternational surveys 30% of the population over 50 is at risk, so Hungary nearly one million people can be affected. The stenosis and obstruction of the arteries are serious health and social burden due to the estimated 7,000 limb amputations per year [1]. Amputation is the removal of body parts and organs with all types of tissues [2]. Peripheral vascular disease, commonly known as atherosclerosis, is the manifestation of general atherosclerosis. In this disease stenosis mostly occurs the arteries of the lower limb, late diagnosis of it can lead to amputation. Data characterizes the national situation; 2005 more amputations were performed than surgeries for lower limb artery reconstructions [3]. 6,733 lower limb amputations were performed Hungarian vascular surgery departments Accordg to the database of Gyógyfok approximately 65 amputations can be expected for 100,000 habitants per year Hungary, 57 of them is lower limb amputation. Just over one third of the lower limb amputations done below the level of the knee (from these 1/3 is performed on the lower leg and at the level of the ankle). Comparative data with the Western European and Northern American States: lower limb amputations per 100,000 habitants per year, more than 50% knee is kept ( some countries is about 60%), only 5 10% of these amputations are at the level of the ankle or the lower leg [4]. Diseases that lead to lower limb amputation the order of prevalence: vascular disease and diabetes (>80%), trauma (14%), cancer (<3%), flammatory disease, limb malformation and other causes together (<4%) [5]. The possibility of amputation creases by agg. Most frequently performed years old people. More than 70% of the amputees are males % of all nontraumatic amputations performed patients with diabetes the United States that means 20 30,000 amputations every year. Also approximately 20,000 lower limb amputations are performed people with diabetes Germany per year [6]. II. AIM OF THE STUDY The aim of the study was to determe the whole body weight and body mass dex (BMI) of lower limb amputees, to apply a methodology that can be used practice. In this way we calculated BMI from the measured or estimated body weight and body height and compare the BMI and the corrected BMI. We also aimed to support the rehabilitation of these patients with this method. III. METHODS Determation of corrected BMI that is required (nutritional) rehabilitation. Whole body weight was determed from measured or estimated body weight and body height. There are different ways to estimate body height. We can calculate it form the length of the ulna. Measure the length

2 December, between the processus olecranon and the processus styloideus, if it is possible on the left side. Estimate height accordg to sex and age with the help of a table. In this way we can clude people the screeng who were dropped out earlier or produced false results. Another way to estimate body height is the application of a formula. While the arm is at the height of the shoulder Measure the distance between the middle of the collarbone and the mid fger (demispan). From the result of it we can calculate body height. There are two different formulas, one for females, and one for males. Females: Height cm = (1.35 demispan cm) Males: Height cm = (1.40 demispan cm) [7] Calculation of BMI from measured body weight and body height without correction is often an correctly applied method the practice. This method results differences compared with the corrected BMI. Accordg to BMI without correction we can state that, if the basis of the nutritional rehabilitation is false the rehabilitation cannot be successful. Estimated BMI First, we have to estimate the body weight of the patient cludg the missg limb. The entire leg is 16% of the whole body. There is example for the calculation: A man whose height is 172cm and his weight is 58kg, one of his entire leg was amputated. Corrected BMI: Estimated body weight = actual body weight (1 the percentage of the missg limb) Example: 58 (kg) (1 0.16) = 58 (kg) 0.84 = 69.1 (kg) Calculation of BMI = estimated body weight body height (m)2 Example: 69.1 ( ) = 23.4 Calculation of BMI without correction = 58 ( ) = 19.6 In this example the differences can be well recognized. IV. SUBJECTS Adult lower limb amputees took part the survey, 49 (31 males and 18 females) unilateral amputees and 10 (8 males and 2 females) both legs (femur) amputees. Their body weight and body height was measured or estimated, than the BMI was calculated. V. RESULTS Calculation of BMI from measured body weight and body height without correction is often an correctly applied method the practice. Authors represent the distortg results of this correct. Accordg to the BMI values calculated from the origal data only one third of these patients belonged to the optimal category and one third have BMI Considerg the weight of the missg limb 45 (76.3%) patients belonged to other category, from the 59 patients. We compared the BMI values with and without correction (Figure 1.). Accordg to the result 100% of the males the overweight category, 91.7% the optimal category and the undernourished category were classified wrong. Only the extreme obese category were all the patients the good category. If we calculate without correction, the body weight of these people is less than calculatg with the weight of the missg leg. To get correct results we have to calculate with the weight of the leg. Many times it is also a fault the practice that the medical stuff says to the patients after the surgery that weight loss happened because of the surgery and the patient have to ga these kilograms back. 100% of the females with optimal BMI, of the overweight, 50% of the obese and 50% of the undernourished were the wrong group accordg to the comparison of BMI and corrected BMI values (Figure 2.). Only the extreme obese category were 100% of the patients (both males and females) the good category comparg the BMI values with and without correction. It is obvious, because if someone is extremely obese without the weight of the missg leg, the patient also belongs to the extreme obese category with the weight of the leg. There are no differences the category his case, but the correct BMI value is very important the rehabilitation, because there are differences the nutritional/feedg plan and rehabilitation, for example between a patient with BMI = 46 [kg/m2] and a patient with a BMI = 63 [kg/m2]. The result of both legs amputees are differg from the group of unilateral amputees. Both legs missg, this way there are major differences between the results of BMI calculation with and without correction. All patients were a wrong category except patients from the extremely obese group. If we consider the five BMI categories we can see that 80% is the possibility of categorizg patients a wrong group. The biggest problem is the optimal and overweight group. Almost every patient is the wrong category. A 82 years old male with bilateral amputations had the highest BMI, without correction it was 46.4 [kg/m2]; with correction it was 67.5 [kg/m2]. A 67 years old male had the lowest BMI, without correction it was 13.8 [kg/m2], with correction it was 20.1 [kg/m2]. We can see the huge differences between the BMI values. There are differences the nutritional therapy of a male with a BMI 46.4 [kg/m2] and with 67.5 [kg/m2]. A male whose BMI is 13.8 [kg/m2] needs therapy because he is malnourished and also the degree of malnutrition is serious, so he needs nutritional therapy, the BMI 20.1 [kg/m2] is optimal, so it is a fault if we start to feed him to ga weight because he becomes overweight

3 December, % 25.0% 8.3% 91.7% Males, correct categorization Males, false categorization Figure 2. Correct and false BMI categories of unilateral male amputees Females, correct categorization Females, false categorization Figure 2. Correct and false BMI categories of unilateral female amputees

4 December, Both legs amputees, correct categorization Both legs amputees, false categorization Figure 3. Correct and false BMI categories of bilateral amputees 6.3% 93.8% 5.0% 95.0% All, correct categorization All, false categorization Figure 4. Correct and false BMI categories of all patients Uncorrected BMI formula underestimates body fat unilateral amputees and overestimates body fat subjects with bilateral amputations [8]. In bilateral amputees if we use the corrected body weight and the uncorrected body weight it also underestimates the BMI, as we can see the results. VI. CONCLUSIONS Authors are aware of the limited usability of BMI (especially regardg people older 65), however, draw attention to the correct classification that results form false route use and the opportunities for practical use. The nutritional status of lower limb amputees is a very important factor many aspects: after the surgery wound heelg, later because of the prosthesis make a prosthesis that is right size and also to achieve optimal nutritional status and keep it. Steps for successful (nutritional) rehabilitation: 1. Correct determation of nutritional status 2. To make a nutritional/ feedg plan 3. Regular control, modify the plan if it is necessary These steps needed and help to make the prosthesis and the use of it. All these steps make it possible for the patients to move more and this way the rehabilitation will be successful. REFERENCES [1] Kollár L., Szegedi J., Lappangó betegség súlyos következmények folyamatosan küzdő szakma. Orvosi Hetilap 2007, vol. 47. pp [2] Kulmann L., Ortopédiai betegek rehabilitációja. In: Katona F., Siegler J. (szerk.), Rehabilitáció. Budapest: Medica 1999, pp. 99. [3] Boromisza P., Erek védelmében. Országos program a tünetmentes érszűkület felkutatásáért. IME 2010/3. pp

5 December, [4] Magyar Angiológiai és Érsebészeti Társaság: A végtagamputáció szakmai irányelve. Angiológiai Útmutató. 2009/09. amputacio%20szakmai%20iranyelv.pdf ( ) [5] Kulmann L., Belicza É., László G., Az alsó végtag amputáció kétéves eredményei Magyarországon, országos adatbázis lapján. Orvosi Hetilap 1997, vol. 37 pp [6] Wkler G., A diabeteses lábszdróma: az ellátás terdiszcipláris vonatkozásai. In: Baranyai É., Wkler G. (szerk.), Válogatott fejezetek a klikai diabetológiából. Budapest: Medica, 2000, pp [7] A guide to completg the Mi Nutritional Assessment MNA, Nestlé Nutrition Institute. [s. a.] [8] Tzamaloukas AH., Patron A., Malhotra D., Body mass dex amputees. JPEN Journal of Parenteral and Enteral Nutrition, 1994, vol. 4. pp