Phlebology http://phl.sagepub.com/
The impact of obesity on venous insufficiency AC Seidel, CEQ Belczak, MB Campos, RB Campos and DS Harada Phlebology published online 5 September 2014 DOI: 10.1177/0268355514551087 The online version of this article can be found at: http://phl.sagepub.com/content/early/2014/09/04/0268355514551087
Published by: http://www.sagepublications.com
Additional services and information for Phlebology can be found at: Email Alerts: http://phl.sagepub.com/cgi/alerts Subscriptions: http://phl.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav
>> OnlineFirst Version of Record - Sep 5, 2014 What is This?
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
Phlebology OnlineFirst, published on September 5, 2014 as doi:10.1177/0268355514551087
Original Article
The impact of obesity on venous insufficiency
Phlebology 0(0) 1–6 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0268355514551087 phl.sagepub.com
AC Seidel1, CEQ Belczak2, MB Campos1, RB Campos1 and DS Harada1
Abstract Association between chronic venous disease and obesity has recently been studied, with indications that it may worsen in obese patients. The aim of study was to correlate clinical classes of chronic venous disease according to Clinical Etiology Anatomy Pathophysiology (CEAP) classification and body mass index, as well as to compare the severity of chronic venous disease in obese and nonobese patients. This retrospective cross-sectional prevalence study was conducted at the Maringa´ State University and Belczak Vascular Center along a period of 2 years, consisting of a random sample of 482 patients with complaints compatible with chronic venous disease. Data obtained from patient’s files included gender, age, weight and height (for calculating body mass index), and clinical class (C) of chronic venous disease according to CEAP classification. Statistical analysis included Spearman’s correlation coefficient, Chi-square test (for comparing frequencies), and Student’s t-test (for comparing means). Significant positive correlation between body mass index and clinical classes was established for women (0.43), but not for men (0.07). Obesity (body mass index 30.0) was significantly more frequent in patients with chronic venous disease in clinical classes 3 (p < 0.001) and 4 (p ¼ 0.002) and less frequent in patients with chronic venous disease in clinical class 1 (p < 0.001). This study evidenced significant correlation between body mass index and clinical classes of chronic venous disease in women, but not in men. It also corroborated the negative impact of obesity on the clinical severity of chronic venous disease.
Keywords Venous insufficiency, obesity, lower extremity
Introduction Chronic venous disease (CVD) of the lower limbs (LL) occurs when the blood return is impaired due to venous hypertension in these limbs that may result from valve incompetence or obstruction of venous flow with or without dysfunction of the associated calf muscle pump. It is an important public health problem, given its high morbidity, impact on quality of life, high rates of absenteeism, and high labor costs to the public treasury.1 The clinical severity of venous disease has been widely assessed by means of Clinical Etiology Anatomy Pathophysiology (CEAP) classification for chronic venous disorders, based on clinical signs (C), etiology (E), anatomic distribution (A), and pathophysiological dysfunction (P), which has been used as a common scientific language and a systematic guide of daily clinical practice.2 Obesity has been supposed to be one of the main risk factors for VI. Several studies have related CVD to obesity, and although many of them have shown a strong positive association, there still remains the question as to its role as a primary cause or as an
aggravating factor in venous reflux. It has been observed that the CVD is more severe in obese patients, who frequently present more ulcers; these findings are consistent with the hypothesis that obesity worsens the clinical manifestations of CVD instead of starting it.3,4 The Edinburgh study showed that the body mass index (BMI) was significantly higher in patients with many venous segments compromised when compared to those who had little or no reflux.5 Considering the increasing prevalence of obesity in western countries, just where venous disease is more frequent,6 this study aimed at correlating clinical classes of CVD according to CEAP classification and BMI, 1 Department of Medicine, Maringa´ State University, Maringa´, Parana´, Brazil 2 Belczak Vascular Center, Maringa´, Parana´, Brazil
Corresponding author: Ame´lia C Seidel, Rua Dr. Gerardo Braga, 118, Jardim Vila Rica, 87050610, Maringa´, PR, Brazil. Email: [email protected]
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
2
Phlebology 0(0)
as well as at comparing the severity of CVD in obese and nonobese patients.
Methods This is a retrospective cross-sectional prevalence study conducted at the Maringa´ State University (UEM) and Belczak Vascular Center along a period of 2 years (2012–2013). All patients with complaints compatible with CVD were firstly included in the study with no age limits. These patients underwent duplex ultrasound examination in accordance with the literature for analysis of superficial, deep venous systems and perforating veins. After exclusion of patients presenting signs of deep venous thrombosis, arterial insufficiency, diabetes mellitus, and prior history of venous surgery, data were collected from the files of 482 patients, including gender, age, weight (kg), height (m), and the clinical class (C), according to the CEAP classification. BMI was calculated according to the formula: BMI ¼ (weight/height2). Patients classified in the clinical class 0 of CEAP classification (no visible or palpable signs of venous disease) were also included in the study, if they
presented clinical features of CVD, but without anatomical change (Doppler results), only functional (hypotonic phlebopathy) alterations. For statistical analysis, Chi-square test (confidence index ¼ 95%) was used for comparing data expressed in frequencies; means and standard deviations were compared with the use of Student’s t-test, after application of F-test for the analysis of variances. Spearman’s correlation coefficients were calculated in order to check correlations of BMI with age and clinical classes of CVD. The study protocol was approved by the Ethics Committee of the UEM (304.211).
Results Data presented in Figure 1 show a significant prevalence of female patients (86.7%) over male patients (p < 0.001). Differences were not observed regarding mean age of female and male patients (p ¼ 0.430); mean BMI, however, was significantly higher in the male group (p ¼ 0.012), which was confirmed also in the distribution of patients according to the BMI classes (Table 1). Correlation between age and BMI (r ¼ 0.14 for the whole sample) showed to be very
Figure 1. Data from 482 patients with complaints compatible with venous insufficiency.
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
Seidel et al.
3
Table 1. Distribution of 418 female and 64 male patients according to the BMI classes. Females
Males
BMI classes
n
17.0 ! 18.5 ! 25.0 ! 30.0 ! 35.0 ! >40.0
8 135 79 95 39 62
2.0 32.3 18.9 22.7 9.3 14.8
0 12 7 21 15 9
0.0 18.8 10.9 32.8 23.4 14.1
8 147 86 116 54 71
1.7 30.5 17.8 24.1 11.2 14.7
418
100.0
64
100.0
482
100.0
18.48 24.99 29.99 34.99 39.99
Total
%
n
Total %
n
%
2
X ¼ 19.30; p ¼ 0,001.
Table 2. Distribution of 418 female and 64 male patients according to the clinical classes of CEAP. Clinical classes
Females
Males
of CEAPa
n
0b 1 2 3 4
21 132 184 67 14
5.0 31.6 44.0 16.0 3.4
8 8 29 13 6
12.5 12.5 45.3 20.3 9.4
29 140 213 80 20
6.0 29.0 44.2 16.6 4.2
Total
418
100.0
64
100.0
482
100.0
%
n
Total %
n
%
a
Considering the more severe clinical class between right and left limbs. Both limbs Class 0. X2 ¼ 13.98; p ¼ 0,007. b
weak and not significant both for male (r ¼ 0.05) and female (r ¼ 0.15) patients. The distribution of frequencies regarding the clinical class (C) of CEAP classification for right and left limbs according to the patients’ gender revealed significant differences. In the right limbs, C0 and C4 was significantly more frequent in the male group, while C1 was more frequent in the female group; in the left limbs, the main difference reveals that C1 remained more frequent in the female group (Figure 1). None of the patient was classified in the classes 5 and 6 of CEAP classification usually because they had previous varicose vein surgery or signs of deep venous thrombosis, which were considered exclusion criteria. Positive correlations between age and clinical classes were stronger for females (r ¼ 0.29) and the whole sample (r ¼ 0.27), but weaker for males (r ¼ 0.14). Half of the patients (n ¼ 241) was obese. By dividing patients into obese (BMI 30.0) and nonobese (BMI < 30.0), the frequency of obese males (70.3%) was significantly higher (X2 ¼ 13.13; p ¼ 0.0002) than
that of obese females (53.1%). However, significant differences (p ¼ 0.007) found out in the distribution of female and male patients according to clinical classes (C) of CEAP (Table 2) referred mainly to classes 0 (more frequent in male group) and 1 (more frequent in female group), and less to the more severe classes. The higher frequency of classes 3 and 4 in the male group (29.7%) compared to the female patients (19.4%) was less significant (Figure 2). In fact, correlation between BMI and clinical classes (C) could not be established in the male group (r ¼ 0.07), while in the female group such correlation was significantly positive (r ¼ 0.47), contributing for a positive correlation (r ¼ 0.42) in the sample as a whole. This finding is better illustrated in Figure 3, where it is very clear the continuous ascending line of mean BMI from class 1 to class 4 for females and the whole sample, quit different from the line representing males. When comparing the frequencies of clinical classes of all 964 limbs in obese and nonobese patients, without considering their gender, significant differences were
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
4
Phlebology 0(0)
found out (Table 3), evidencing that nonobese patients were classified in C1 more frequently, while obese patients were classified more frequently in C3 and C4. Such differences were not revealed for Classes 0 and 3 (Figure 4).
Discussion Many studies have been relating CVD to various risk factors, including obesity, so our study was proposed first to simply investigate associations between obesity (determined by BMI) and CVD through clinical evaluation (CEAP). However, since the beginning of data analysis we observed some significant differences
Table 3. Distribution of 964 lower limbs of obese and nonobese patients according to the clinical classes of CEAP.
Figure 2. Graphic representation of the distributions of 418 females and 64 males regarding the severity of the venous disease according to the CEAP classification.
Class 0
Females Males Total p-value
Class 1
Class 0 29.1 + 6.3 31.5 + 5.5 29.7 + 6.3 0.373
Clinical classes
Obese
of CEAP
n
0 1 2 3 4
69 113 169 109 22
14.3 23.4 35.1 22.7 4.5
65 200 190 22 5
13.5 41.5 39.4 4.5 1.0
134 313 359 131 27
13.9 32.5 37.2 13.6 2.8
482
100.0
482
100.0
964
100.0
Total
%
Nonobese
Total
n
n
%
%
2
X ¼ 93.78; p < 0,001.
Class 2 Females
Males
Class 1 26.7+ 5.9 37.4+ 7.0 27.3+ 6.5 < 0.001
Class 2 29.4+ 7.2 31.2+ 5.6 29.6+ 7.0 0.186
Class 3
Class 4
Total
Class 3 36.7+ 7.5 33.3+ 6.9 36.2+ 7.5 0.134
Class 4 46.3+ 7.3 36.4+ 8.9 43.3+ 9.0 0.024
Figure 3. Graphic representation of the mean BMI of 418 females and 64 males regarding the severity of the venous disease according to the CEAP classification (considering the lower limb with more severe VI).
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
Seidel et al.
5 X2 = 24.18; p < 0.001 2 X = 1.23; p = 0.267
2
X = 57.77; p < 0.001
2
X = 0,12; p = 0.729
2 X = 10,70; p = 0.002
Class 0
Class 1
Class 2 Obese
Non-obese
Class 3
Class 4
Total
Figure 4. Graphic representation of the distributions of 964 lower limbs regarding the severity of the venous disease according to the CEAP classification.
between female and male patients, which led us to enlarge the ways of analysis, considering also gender differences. In fact, we could absolutely corroborate the findings of other researchers3,4 that obesity has its impact on the severity of CVD. However, this is a valid statement for women, representing 86.7% of the sample, but not for men. Male patients presented significantly higher BMI means, but not in the more severe classes of CVD (see Figure 3), and they were significantly more frequent than females both in class 0 and classes 3–4. Additionally, significant positive correlations were established for women (r ¼ 0.43), but not for men (r ¼ 0.07). In other words, the impact of obesity on CVD in male patients seems to be different than that in women. Such differences between females and males patients can be represented by the fact that obese women have higher concentrations of circulating estrogen than nonobese women, and this increased estrogen plus the central adiposity may expand the intravascular volume, impairing venous return.7 In this sense, Beebe-Dimmer et al.7 reviewed several studies and noticed that the relationship between body weight and varicose veins could be explained by the same mechanism observed during pregnancy. Another explanation could be due to the small number of male patients, thus the execution of other studies may be needed to confirm this finding. Seidel et al.8 studied the prevalence of varicose veins in women and in patients between 50 and 59 years and compared the prevalence of CVD in obese and nonobese patients. They did not find out significant differences in the prevalence of varicose veins in obese and nonobese (p ¼ 0.757), although the most commonly
affected veins and the clinical features were different in the two groups. The impact of higher BMI on the CVD severity, mainly in women, and how this effect could be explained are yet to be clearly elucidated. The association between obesity and venous hemodynamic changes has been mainly related to visceral obesity, which causes an increase in intra-abdominal pressure. This high pressure is transmitted to the ends of the femoral vein, leading to distension of the LLs’ vein walls, which favor stasis and venous valve dysfunction. This occurs because the venous vessel wall is permanently under greater tension in the obese.9 Additionally, the increased intra-abdominal pressure may further compromise the lymphatic return, creating a combined effect of lymphovenous hypertension.10 Danielsson et al.11 presented results confirming the association between femoral vein pressure and intraabdominal pressure, measured indirectly by the bladder pressure, in a study in which obesity was considered an independent risk factor for the disease progression. Sugerman et al.12 also found a correlation between increased intra-abdominal pressure and venous stasis, suggesting that the more severe the patients’ obesity, the more likely it is to have venous stasis in the LLs and other comorbidities. The surgically induced weight loss was successful in the complete resolution or marked improvement of venous stasis and other comorbidities, which were before refractory to other forms of treatment. There are other factors that may contribute to the disease severity in obese patients, such as lack of physical activity, which could restrict the venous emptying
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
6
Phlebology 0(0)
of the leg. It is assumed that the morbidly obese, due to their weight and sedentary lifestyle, have a limited mobility of the ankle joint, thus compromising the broad contraction of the triceps surae muscle with consequent impairment of the calf pump function, which certainly must contribute to the onset or worsening of the LL CVD of these individuals.11 Compression therapy with elastic stockings, which reduces the venous hypertension, is not always applicable to the legs of obese patients, and not using them may also contribute to a higher incidence of more severe illness in obese patients.11 In turn, one must consider that patients with CVD and varicose veins are less physically active due to their condition and, therefore, are more likely to become overweight.7 Moreover, obese patients have ulcers that heal more slowly and return more often. This may be explained by the fact that most are unable to wear suitable socks and shoes and many are even physically unable to reach and see their own feet. This deficiency in performing simple bodily functions may lead to skin tearing and because they have a diminished protective sensation, there is a predisposition to more easily damage the skin.10 Although some studies show no correlation between obesity and CVD, Scott et al.13 demonstrated that obesity remains a risk factor for CVD, even after age adjustment, and suggested that obesity (BMI 30.0) would act as a predisposing factor for deep vein thrombosis, which could also be the cause of CVD in the LLs. This study evidenced significant correlation between BMI and clinical classes of CVD in women, but not in men. It also corroborated the negative impact of obesity on the clinical severity of CVD. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest
References 1. Belczak CEQ, Godoy JMP, Ramos RN, et al. Influeˆncia do turno laboral na formac¸a˜o de edema dos membros inferiores em indivı´ duos normais. J Vasc Bras 2008; 7: 225–230. 2. Eklof B, Rutherford RB, Bergan JJ, et al. Revision of the CEAP classification of chronic venous disorders. Consensus statement. J Vasc Surg 2004; 40: 1248–1252. 3. Van Rij AM, De Alwis CS, Jiang P, et al. Obesity and impaired venous function. Eur J Vasc Endovasc Surg 2008; 35: 739–744. 4. Musil D, Kaletova M and Herman J. Age, body mass index and severity of primary chronic venous disease. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2011; 155: 367–372. 5. Fowkes FGR, Lee AJ, Evans CJ, et al. Lifestyle risk factors for lower limb venous reflux in the general population: Edinburgh vein Study. Int J Epidemiol 2001; 30: 846–852. 6. Robertson L, Evans CJ and Fowkers FG. Epidemiology of chronic venous disease. Phlebology 2008; 23: 103–111. 7. Beebe-Dimmer JL, Pfeifer JR, Engle JS, et al. The epidemiology of chronic venous insufficiency and varicose veins. Ann Epidemiol 2004; 15: 175–184. 8. Seidel AC, Mangolim AS, Rossetti LP, et al. Prevalence of lower limbs superficial venous insufficiency in obese and non-obese patients. J Vasc Bras 2011; 10: 124–130. 9. Willenberg T, Schumacher A, Amann-Vesti B, et al. Impact of obesity on venous hemodynamics of the lower limbs. J Vasc Surg 2010; 52: 664–668. 10. Padberg F, Cerveira J, Lal BK, et al. Does severe venous insufficiency have a different etiology in the morbidly obese? Is it venous? J Vasc Surg 2003; 37: 79–85. 11. Danielsson G, Eklof B, Grandinetti A, et al. The influence of obesity on chronic venous disease. Vasc Endovascular Surg 2002; 36: 271–276. 12. Sugerman HJ, Sugerman EL, Wolfe L, et al. Risks and benefits of gastric bypass in morbidly obese patients with severe venous stasis disease. Ann Surg 2001; 234: 41–46. 13. Scott TE, LaMorte WW, Gorin DR, et al. Risk factors for chronic venous insufficiency: A dual case-control study. J Vasc Surg 1995; 22: 622–628.
None declared.
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
The impact of obesity on venous insufficiency AC Seidel, CEQ Belczak, MB Campos, RB Campos and DS Harada Phlebology published online 5 September 2014 DOI: 10.1177/0268355514551087 The online version of this article can be found at: http://phl.sagepub.com/content/early/2014/09/04/0268355514551087
Published by: http://www.sagepublications.com
Additional services and information for Phlebology can be found at: Email Alerts: http://phl.sagepub.com/cgi/alerts Subscriptions: http://phl.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav
>> OnlineFirst Version of Record - Sep 5, 2014 What is This?
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
Phlebology OnlineFirst, published on September 5, 2014 as doi:10.1177/0268355514551087
Original Article
The impact of obesity on venous insufficiency
Phlebology 0(0) 1–6 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0268355514551087 phl.sagepub.com
AC Seidel1, CEQ Belczak2, MB Campos1, RB Campos1 and DS Harada1
Abstract Association between chronic venous disease and obesity has recently been studied, with indications that it may worsen in obese patients. The aim of study was to correlate clinical classes of chronic venous disease according to Clinical Etiology Anatomy Pathophysiology (CEAP) classification and body mass index, as well as to compare the severity of chronic venous disease in obese and nonobese patients. This retrospective cross-sectional prevalence study was conducted at the Maringa´ State University and Belczak Vascular Center along a period of 2 years, consisting of a random sample of 482 patients with complaints compatible with chronic venous disease. Data obtained from patient’s files included gender, age, weight and height (for calculating body mass index), and clinical class (C) of chronic venous disease according to CEAP classification. Statistical analysis included Spearman’s correlation coefficient, Chi-square test (for comparing frequencies), and Student’s t-test (for comparing means). Significant positive correlation between body mass index and clinical classes was established for women (0.43), but not for men (0.07). Obesity (body mass index 30.0) was significantly more frequent in patients with chronic venous disease in clinical classes 3 (p < 0.001) and 4 (p ¼ 0.002) and less frequent in patients with chronic venous disease in clinical class 1 (p < 0.001). This study evidenced significant correlation between body mass index and clinical classes of chronic venous disease in women, but not in men. It also corroborated the negative impact of obesity on the clinical severity of chronic venous disease.
Keywords Venous insufficiency, obesity, lower extremity
Introduction Chronic venous disease (CVD) of the lower limbs (LL) occurs when the blood return is impaired due to venous hypertension in these limbs that may result from valve incompetence or obstruction of venous flow with or without dysfunction of the associated calf muscle pump. It is an important public health problem, given its high morbidity, impact on quality of life, high rates of absenteeism, and high labor costs to the public treasury.1 The clinical severity of venous disease has been widely assessed by means of Clinical Etiology Anatomy Pathophysiology (CEAP) classification for chronic venous disorders, based on clinical signs (C), etiology (E), anatomic distribution (A), and pathophysiological dysfunction (P), which has been used as a common scientific language and a systematic guide of daily clinical practice.2 Obesity has been supposed to be one of the main risk factors for VI. Several studies have related CVD to obesity, and although many of them have shown a strong positive association, there still remains the question as to its role as a primary cause or as an
aggravating factor in venous reflux. It has been observed that the CVD is more severe in obese patients, who frequently present more ulcers; these findings are consistent with the hypothesis that obesity worsens the clinical manifestations of CVD instead of starting it.3,4 The Edinburgh study showed that the body mass index (BMI) was significantly higher in patients with many venous segments compromised when compared to those who had little or no reflux.5 Considering the increasing prevalence of obesity in western countries, just where venous disease is more frequent,6 this study aimed at correlating clinical classes of CVD according to CEAP classification and BMI, 1 Department of Medicine, Maringa´ State University, Maringa´, Parana´, Brazil 2 Belczak Vascular Center, Maringa´, Parana´, Brazil
Corresponding author: Ame´lia C Seidel, Rua Dr. Gerardo Braga, 118, Jardim Vila Rica, 87050610, Maringa´, PR, Brazil. Email: [email protected]
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
2
Phlebology 0(0)
as well as at comparing the severity of CVD in obese and nonobese patients.
Methods This is a retrospective cross-sectional prevalence study conducted at the Maringa´ State University (UEM) and Belczak Vascular Center along a period of 2 years (2012–2013). All patients with complaints compatible with CVD were firstly included in the study with no age limits. These patients underwent duplex ultrasound examination in accordance with the literature for analysis of superficial, deep venous systems and perforating veins. After exclusion of patients presenting signs of deep venous thrombosis, arterial insufficiency, diabetes mellitus, and prior history of venous surgery, data were collected from the files of 482 patients, including gender, age, weight (kg), height (m), and the clinical class (C), according to the CEAP classification. BMI was calculated according to the formula: BMI ¼ (weight/height2). Patients classified in the clinical class 0 of CEAP classification (no visible or palpable signs of venous disease) were also included in the study, if they
presented clinical features of CVD, but without anatomical change (Doppler results), only functional (hypotonic phlebopathy) alterations. For statistical analysis, Chi-square test (confidence index ¼ 95%) was used for comparing data expressed in frequencies; means and standard deviations were compared with the use of Student’s t-test, after application of F-test for the analysis of variances. Spearman’s correlation coefficients were calculated in order to check correlations of BMI with age and clinical classes of CVD. The study protocol was approved by the Ethics Committee of the UEM (304.211).
Results Data presented in Figure 1 show a significant prevalence of female patients (86.7%) over male patients (p < 0.001). Differences were not observed regarding mean age of female and male patients (p ¼ 0.430); mean BMI, however, was significantly higher in the male group (p ¼ 0.012), which was confirmed also in the distribution of patients according to the BMI classes (Table 1). Correlation between age and BMI (r ¼ 0.14 for the whole sample) showed to be very
Figure 1. Data from 482 patients with complaints compatible with venous insufficiency.
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
Seidel et al.
3
Table 1. Distribution of 418 female and 64 male patients according to the BMI classes. Females
Males
BMI classes
n
17.0 ! 18.5 ! 25.0 ! 30.0 ! 35.0 ! >40.0
8 135 79 95 39 62
2.0 32.3 18.9 22.7 9.3 14.8
0 12 7 21 15 9
0.0 18.8 10.9 32.8 23.4 14.1
8 147 86 116 54 71
1.7 30.5 17.8 24.1 11.2 14.7
418
100.0
64
100.0
482
100.0
18.48 24.99 29.99 34.99 39.99
Total
%
n
Total %
n
%
2
X ¼ 19.30; p ¼ 0,001.
Table 2. Distribution of 418 female and 64 male patients according to the clinical classes of CEAP. Clinical classes
Females
Males
of CEAPa
n
0b 1 2 3 4
21 132 184 67 14
5.0 31.6 44.0 16.0 3.4
8 8 29 13 6
12.5 12.5 45.3 20.3 9.4
29 140 213 80 20
6.0 29.0 44.2 16.6 4.2
Total
418
100.0
64
100.0
482
100.0
%
n
Total %
n
%
a
Considering the more severe clinical class between right and left limbs. Both limbs Class 0. X2 ¼ 13.98; p ¼ 0,007. b
weak and not significant both for male (r ¼ 0.05) and female (r ¼ 0.15) patients. The distribution of frequencies regarding the clinical class (C) of CEAP classification for right and left limbs according to the patients’ gender revealed significant differences. In the right limbs, C0 and C4 was significantly more frequent in the male group, while C1 was more frequent in the female group; in the left limbs, the main difference reveals that C1 remained more frequent in the female group (Figure 1). None of the patient was classified in the classes 5 and 6 of CEAP classification usually because they had previous varicose vein surgery or signs of deep venous thrombosis, which were considered exclusion criteria. Positive correlations between age and clinical classes were stronger for females (r ¼ 0.29) and the whole sample (r ¼ 0.27), but weaker for males (r ¼ 0.14). Half of the patients (n ¼ 241) was obese. By dividing patients into obese (BMI 30.0) and nonobese (BMI < 30.0), the frequency of obese males (70.3%) was significantly higher (X2 ¼ 13.13; p ¼ 0.0002) than
that of obese females (53.1%). However, significant differences (p ¼ 0.007) found out in the distribution of female and male patients according to clinical classes (C) of CEAP (Table 2) referred mainly to classes 0 (more frequent in male group) and 1 (more frequent in female group), and less to the more severe classes. The higher frequency of classes 3 and 4 in the male group (29.7%) compared to the female patients (19.4%) was less significant (Figure 2). In fact, correlation between BMI and clinical classes (C) could not be established in the male group (r ¼ 0.07), while in the female group such correlation was significantly positive (r ¼ 0.47), contributing for a positive correlation (r ¼ 0.42) in the sample as a whole. This finding is better illustrated in Figure 3, where it is very clear the continuous ascending line of mean BMI from class 1 to class 4 for females and the whole sample, quit different from the line representing males. When comparing the frequencies of clinical classes of all 964 limbs in obese and nonobese patients, without considering their gender, significant differences were
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
4
Phlebology 0(0)
found out (Table 3), evidencing that nonobese patients were classified in C1 more frequently, while obese patients were classified more frequently in C3 and C4. Such differences were not revealed for Classes 0 and 3 (Figure 4).
Discussion Many studies have been relating CVD to various risk factors, including obesity, so our study was proposed first to simply investigate associations between obesity (determined by BMI) and CVD through clinical evaluation (CEAP). However, since the beginning of data analysis we observed some significant differences
Table 3. Distribution of 964 lower limbs of obese and nonobese patients according to the clinical classes of CEAP.
Figure 2. Graphic representation of the distributions of 418 females and 64 males regarding the severity of the venous disease according to the CEAP classification.
Class 0
Females Males Total p-value
Class 1
Class 0 29.1 + 6.3 31.5 + 5.5 29.7 + 6.3 0.373
Clinical classes
Obese
of CEAP
n
0 1 2 3 4
69 113 169 109 22
14.3 23.4 35.1 22.7 4.5
65 200 190 22 5
13.5 41.5 39.4 4.5 1.0
134 313 359 131 27
13.9 32.5 37.2 13.6 2.8
482
100.0
482
100.0
964
100.0
Total
%
Nonobese
Total
n
n
%
%
2
X ¼ 93.78; p < 0,001.
Class 2 Females
Males
Class 1 26.7+ 5.9 37.4+ 7.0 27.3+ 6.5 < 0.001
Class 2 29.4+ 7.2 31.2+ 5.6 29.6+ 7.0 0.186
Class 3
Class 4
Total
Class 3 36.7+ 7.5 33.3+ 6.9 36.2+ 7.5 0.134
Class 4 46.3+ 7.3 36.4+ 8.9 43.3+ 9.0 0.024
Figure 3. Graphic representation of the mean BMI of 418 females and 64 males regarding the severity of the venous disease according to the CEAP classification (considering the lower limb with more severe VI).
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
Seidel et al.
5 X2 = 24.18; p < 0.001 2 X = 1.23; p = 0.267
2
X = 57.77; p < 0.001
2
X = 0,12; p = 0.729
2 X = 10,70; p = 0.002
Class 0
Class 1
Class 2 Obese
Non-obese
Class 3
Class 4
Total
Figure 4. Graphic representation of the distributions of 964 lower limbs regarding the severity of the venous disease according to the CEAP classification.
between female and male patients, which led us to enlarge the ways of analysis, considering also gender differences. In fact, we could absolutely corroborate the findings of other researchers3,4 that obesity has its impact on the severity of CVD. However, this is a valid statement for women, representing 86.7% of the sample, but not for men. Male patients presented significantly higher BMI means, but not in the more severe classes of CVD (see Figure 3), and they were significantly more frequent than females both in class 0 and classes 3–4. Additionally, significant positive correlations were established for women (r ¼ 0.43), but not for men (r ¼ 0.07). In other words, the impact of obesity on CVD in male patients seems to be different than that in women. Such differences between females and males patients can be represented by the fact that obese women have higher concentrations of circulating estrogen than nonobese women, and this increased estrogen plus the central adiposity may expand the intravascular volume, impairing venous return.7 In this sense, Beebe-Dimmer et al.7 reviewed several studies and noticed that the relationship between body weight and varicose veins could be explained by the same mechanism observed during pregnancy. Another explanation could be due to the small number of male patients, thus the execution of other studies may be needed to confirm this finding. Seidel et al.8 studied the prevalence of varicose veins in women and in patients between 50 and 59 years and compared the prevalence of CVD in obese and nonobese patients. They did not find out significant differences in the prevalence of varicose veins in obese and nonobese (p ¼ 0.757), although the most commonly
affected veins and the clinical features were different in the two groups. The impact of higher BMI on the CVD severity, mainly in women, and how this effect could be explained are yet to be clearly elucidated. The association between obesity and venous hemodynamic changes has been mainly related to visceral obesity, which causes an increase in intra-abdominal pressure. This high pressure is transmitted to the ends of the femoral vein, leading to distension of the LLs’ vein walls, which favor stasis and venous valve dysfunction. This occurs because the venous vessel wall is permanently under greater tension in the obese.9 Additionally, the increased intra-abdominal pressure may further compromise the lymphatic return, creating a combined effect of lymphovenous hypertension.10 Danielsson et al.11 presented results confirming the association between femoral vein pressure and intraabdominal pressure, measured indirectly by the bladder pressure, in a study in which obesity was considered an independent risk factor for the disease progression. Sugerman et al.12 also found a correlation between increased intra-abdominal pressure and venous stasis, suggesting that the more severe the patients’ obesity, the more likely it is to have venous stasis in the LLs and other comorbidities. The surgically induced weight loss was successful in the complete resolution or marked improvement of venous stasis and other comorbidities, which were before refractory to other forms of treatment. There are other factors that may contribute to the disease severity in obese patients, such as lack of physical activity, which could restrict the venous emptying
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
XML Template (2014) [3.9.2014–7:31pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/PHLJ/Vol00000/140107/APPFile/SG-PHLJ140107.3d
(PHL)
[1–6] [PREPRINTER stage]
6
Phlebology 0(0)
of the leg. It is assumed that the morbidly obese, due to their weight and sedentary lifestyle, have a limited mobility of the ankle joint, thus compromising the broad contraction of the triceps surae muscle with consequent impairment of the calf pump function, which certainly must contribute to the onset or worsening of the LL CVD of these individuals.11 Compression therapy with elastic stockings, which reduces the venous hypertension, is not always applicable to the legs of obese patients, and not using them may also contribute to a higher incidence of more severe illness in obese patients.11 In turn, one must consider that patients with CVD and varicose veins are less physically active due to their condition and, therefore, are more likely to become overweight.7 Moreover, obese patients have ulcers that heal more slowly and return more often. This may be explained by the fact that most are unable to wear suitable socks and shoes and many are even physically unable to reach and see their own feet. This deficiency in performing simple bodily functions may lead to skin tearing and because they have a diminished protective sensation, there is a predisposition to more easily damage the skin.10 Although some studies show no correlation between obesity and CVD, Scott et al.13 demonstrated that obesity remains a risk factor for CVD, even after age adjustment, and suggested that obesity (BMI 30.0) would act as a predisposing factor for deep vein thrombosis, which could also be the cause of CVD in the LLs. This study evidenced significant correlation between BMI and clinical classes of CVD in women, but not in men. It also corroborated the negative impact of obesity on the clinical severity of CVD. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest
References 1. Belczak CEQ, Godoy JMP, Ramos RN, et al. Influeˆncia do turno laboral na formac¸a˜o de edema dos membros inferiores em indivı´ duos normais. J Vasc Bras 2008; 7: 225–230. 2. Eklof B, Rutherford RB, Bergan JJ, et al. Revision of the CEAP classification of chronic venous disorders. Consensus statement. J Vasc Surg 2004; 40: 1248–1252. 3. Van Rij AM, De Alwis CS, Jiang P, et al. Obesity and impaired venous function. Eur J Vasc Endovasc Surg 2008; 35: 739–744. 4. Musil D, Kaletova M and Herman J. Age, body mass index and severity of primary chronic venous disease. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2011; 155: 367–372. 5. Fowkes FGR, Lee AJ, Evans CJ, et al. Lifestyle risk factors for lower limb venous reflux in the general population: Edinburgh vein Study. Int J Epidemiol 2001; 30: 846–852. 6. Robertson L, Evans CJ and Fowkers FG. Epidemiology of chronic venous disease. Phlebology 2008; 23: 103–111. 7. Beebe-Dimmer JL, Pfeifer JR, Engle JS, et al. The epidemiology of chronic venous insufficiency and varicose veins. Ann Epidemiol 2004; 15: 175–184. 8. Seidel AC, Mangolim AS, Rossetti LP, et al. Prevalence of lower limbs superficial venous insufficiency in obese and non-obese patients. J Vasc Bras 2011; 10: 124–130. 9. Willenberg T, Schumacher A, Amann-Vesti B, et al. Impact of obesity on venous hemodynamics of the lower limbs. J Vasc Surg 2010; 52: 664–668. 10. Padberg F, Cerveira J, Lal BK, et al. Does severe venous insufficiency have a different etiology in the morbidly obese? Is it venous? J Vasc Surg 2003; 37: 79–85. 11. Danielsson G, Eklof B, Grandinetti A, et al. The influence of obesity on chronic venous disease. Vasc Endovascular Surg 2002; 36: 271–276. 12. Sugerman HJ, Sugerman EL, Wolfe L, et al. Risks and benefits of gastric bypass in morbidly obese patients with severe venous stasis disease. Ann Surg 2001; 234: 41–46. 13. Scott TE, LaMorte WW, Gorin DR, et al. Risk factors for chronic venous insufficiency: A dual case-control study. J Vasc Surg 1995; 22: 622–628.
None declared.
Downloaded from phl.sagepub.com at UNIV TORONTO on November 19, 2014
