Epidemiological study on varicose veins in Budapest

Introduction

A survey which gives an overview of the frequency of varicose veins of the lower limb in Hungary is important for two main reasons. First of all, it is important for the Hungarian health service. Secondly, there are only a few available epidemiological data about Eastern European countries in any international forum ¹ and no data about Hungary.

Epidemiological research usually focuses on fatal or disabling disorders all over the world including Hungary. Varicosity and its complications have been neglected accordingly, as being abnormalities that ‘only’ impair the quality of life of patients. ² Nevertheless, the size of the population afflicted by chronic venous diseases is enormous and so is the expenditure invested in the management of this disease. ³

Defining the expression ‘varicose veins’ accurately is indispensable to any survey purporting to appraise the prevalence of lower-extremity varicosity – the outcome of which is obviously dependent on the definition. ⁴ Without intending to engage in an exhaustive discussion, some aspects of this seemingly straightforward but vague issue must be characterized. What are the most important problems as regards clinical practice? Should all the veins visible under the skin (such as ‘spider’ veins, dilated but asymptomatic vessels or bulging veins of sports people) be considered varices? According to the most widely accepted definition, varices are dilated, elongated, tortuous segments of the superficial venous system with incompetent valves that allow retrograde flow (reflux). ^5–9 This definition corresponds only to C2 class of CEAP (clinical, aetiological, anatomical and pathological) classification. On the other hand, the visible, but non-dilated veins, as well as the intact, bulging veins of sports professionals will not be regarded as varices, but distended albeit asymptomatic veins will be considered as varicose. Spider veins marked as C1 in CEAP classification were included in our study because we agree that they have some influence on the venous circulation of the limb. ^10,11 It means that our study differs from earlier Hungarian studies ^12,13 and comprises different types of CVDs from C1 to C6.

Methods

Thirty-five family practitioners having some practice in the diagnosis and management of vascular diseases were invited to participate in this epidemiological survey conducted in practices located in Budapest and the vicinity. Recruited investigators completed a training course before receiving the survey forms and a Doppler ultrasound device provided for the purposes of the study. ¹⁴ The survey was conducted on 566 individuals aged 14–92 years.

Each questionnaire was designed to record data from six patients – this feature was meant to stress that interviewing at least three (or more) consecutive patients is expected for randomization similar to the study by Benigni et al. ¹⁵ The survey form contained questions for recording physical findings, in addition to the data of medical history. All questions were designed to elicit positive/negative (yes or no) answers.

Patients were ranked into the CEAP classes and in every case the more serious problem and therefore the higher class was recorded into the statistical analysis. ¹⁶

Accumulated data were analysed using the SAS software package (version 8.1). Null hypotheses on the comparison of prevalence data were investigated with the chi-square test or its more accurate version, Fisher's exact test, when appropriate.

Results

The age distribution of the study was dominated by the age group of the 50–60-year-olds, whereas the number of individuals younger than 30 or older than 80 years of age was small. The mean age of the study population was 49.6; the male-to-female ratio was 1:1.6 (216/350). The prevalence of varicosity was rather high, 57.1% (323/566) in the studied population.

Stratifying the study population into age groups reveals the definite influence of age on occurrence. While the prevalence of varicosity is as low as 12.5% in those under 20 years of age, it is as high as 82.1% in the elderly, 71–80-year-old population (Table 1). This age-related increase is confirmed also by the comparison of mean age, which was 49.6 years for the whole study population and 56.1 years for the group of patients with varicosity.

Mean body weight was 66.7 kg for women and 79.0 kg for men. The proportion of overweight individuals was 28.1% (body mass index > 30 kg/m²). This group was characterized by a higher (76.7%) prevalence of varicosity.

The distribution of the study population by level of physical activity was as follows: 26.2% pursued a sedentary occupation, 30.7% were blue-collar workers and 2.8% engaged in physically demanding sports. Jobs involving a lot of standing are associated with a higher incidence of varicosity. This is in agreement with the 64.9% prevalence of varicosity found in individuals employed in such jobs, compared with the 54.3% prevalence associated with sedentary work. Lower-extremity varicosity was ascertained in 76.1% of blue-collar workers.

A total of 202 of the 350 female participants had children; most of them (40.5%) had had two children and the incidence of more than three children (>3 deliveries) was very much in the minority at 4.0%. The proportion of nulliparous women was 22.4%, 20.7% were primiparous and 12.4% had delivered three children (Table 2).

Nulliparity was associated with a 40.3% prevalence of varicosity, which afflicted 73.7% of parous women. Childbirth seems to be an evident risk factor of lower-extremity varicosity (P < 0.005). This relationship is corroborated by the correlation between the number of deliveries and prevalence: varicosity was observed in 40.3% of nulliparous, 66.1% of primiparous and 71.9% of biparous women, as well as in 75.0% of women with more than three deliveries (Table 3).

Women are exposed to further hormonal influences, including oral contraceptives (OC) and postmenopausal hormone replacement therapy (HRT). In this survey, 43.1% of women (151/350) were regular OC users; 90 of these 151 women had varicosity and 61 did not. In the subgroup of nulliparous women, OC use was not associated with a higher risk of varicosity (the prevalence of which was 31.6% in nulliparous OC users and 51.7% in non-users; NS). Demonstrating the contributory effect of OCs is complicated by the fact that the frequency of contraceptive use changes with age (as also observed in our series). Considering all female participants together, 59.6% had varicosity, compared with 67.8% of OC non-users (with a higher proportion of elderly women). No relationship could be identified between OC use and varicosity even by analysing the female subgroup younger than 30 years of age separately. In particular, the prevalence of varicosity was 16.2% in <30 years old OC users and 26.1% in non-users, which is statistically not different.

Twenty-five women were receiving HRT. No association could be found between hormone replacement and varicosity, as the prevalence of the latter was almost identical among women receiving/not receiving HRT (64.0 versus 64.3%).

The prevalence of different types of varicosity was also explored (Table 4). This was deemed important, as Hungarian data on the distribution of clinical forms are available only for patients undergoing treatment for varicose veins. However, this distribution is definitely biased as the majority of patients undergo surgery for truncal varicosity, whereas sclerotherapy is predominantly selected for the treatment of ‘spider’ veins. The proportions can be further distorted by ethnicity, gender and parity. ¹⁷ Table 5 summarizes the chronic venous diseases arranged according to CEAP classification.

Discussion

Prevalence data from foreign countries are scattered over a wide range according to geographical location, local customs and type of civilization. ⁴ Often, national data are characterized by homogeneity between individual regions and are also dependent on screening criteria. The lowest published prevalence are 0.1% (New Guinea) and 2.1% (Cook Islands), ⁹ whereas the highest are in Germany 73.3% ¹⁶ and Italy 77.3%, ¹⁸ 81% ¹⁹ and the USA one which it is 74.9%. ²⁰ Hungarian prevalence data seem to be similar to the European average. ^{1,9,10,16,18,19,21,22}

In Hungary, large-scale surveys were conducted by Bonyhádi et al. in 1974, ¹² and in 1977. ¹³ As the populations and results of these two studies are essentially similar, data from the former will be discussed here. This survey was conducted on the population of the 16th district of Budapest; the screening of 3005 adult citizens yielded a 38% prevalence of varicosity. The potential causes of this relatively large difference (compared with the 57.1% prevalence found in our study) are abundant and include a dissimilar definition of varicosity, among others. Unfortunately, neither of the two publications contains any definition of the condition regarded as ‘varicosity’. Furthermore, Bonyhádi et al. ³ surveyed only the 30–60-year-old age group, that is, disregarded populations of higher or lower than average risk of developing varicosity. In our survey, the prevalence of varicosity was 62.1% in the 30–60-year-old age group. The difference between the 38% prevalence found in 1974, and the recently ascertained mean of 57.1% is not thought to reflect the unfavourable influence of changes in living conditions, lifestyle, occupational health and physical activity level. Therefore, the larger numeric value probably suggests the result of a different definition of varicose veins (spider veins C1 were not included) than a true increase in the prevalence of varicosity among the inhabitants of Budapest and the vicinity.

Influence of body weight was examined. Remarkably, the proportions of individuals with/without varicosity are almost equal (49.5–56.1%) in the population with normal body weight. Therefore, excess body weight may be regarded as an obvious risk factor (P < 0.05) – as concluded earlier also by Bonyhádi et al. in Hungary ¹² and by Jawien in Poland. ¹ It is unclear, however, as to whether weight gain should be considered a primary risk factor because body weight increases with advancing age and it is therefore possible that the influence of excess weight is only an indirect reflection of the impact of ageing. ¹⁰ Reversing this dilemma yields the opposite question: is the role of weight gain only secondary? As shown by our results (Table 6), advancing age and weight gain are independent risk factors of developing varicosity. On the one hand, the influence of excess weight is evident in the 51–60-year-old age group: the prevalence of varicosity in normal and overweight individuals was 59.7 versus 73.7% (P < 0.01) (Table 6). On the other hand, the age-related increase of prevalence is apparent also in the subgroup with normal body weight (P < 0.0001).

The higher percentage of varicosity in people with higher levels of physical activity is because heavy work or even prolonged standing, or sitting can be a cause of venous congestion in the lower limbs. It is evident that sitting on the ground is not associated with venous congestion in the lower limb, and therefore, the alternation of squatting, walking and reclining – typical of nomadic lifestyle – seems to be beneficial to the venous system of the lower extremities. It means that the Western lifestyle itself is probably a risk factor for developing varicosity, the prevalence of which is lower in the populations of other civilisations. ⁹

As suggested by the similar prevalence of varicosity among men (44.8%) and nulliparous women (40.3%), female gender itself did not increase the propensity to this form of venous disease in our study in spite of the opinion of Scuderi et al. ²³ and other studies. ^1,15,21 Childbirth, however, was found to be a significant risk factor. ²³ Actually, however, it is pregnancy – and not delivery – that facilitates the development of varicosity as we can observe during the check-ups of pregnant women. In order to make data-acquisition simple and accurate, only the number of completed pregnancies (reflected by the number of deliveries) were recorded. Although this can introduce some inaccuracy into the analysis, this is negligible and cannot bias the result. The foregoing should be kept in mind when interpreting the gender-specific distribution of varicosity (females to males: 64.3% versus 44.8%) found by this survey.

Literature data are less conclusive as regards the unfavourable impact of pregnancy and the indifference of gender. ⁹ Naturally, these findings may reflect the cumulative effect of several factors (e.g. civilized lifestyle and pregnancy); however, our results clearly demonstrate the contributory role of pregnancy in the pathogenesis of varicosity.

Our results provided no evidence for – or against – the role of oral contraception in the aetiology of lower-extremity varicosity. Thus, our data do not confirm the contributory role of hormonal contraception as Kroeger et al. ²¹ and Ziegler ²⁴ did. Our results rather suggest a preventive effect, which is what the Edinburgh venous study also found. ²⁵

Conclusion

Hungarian prevalence data and risk factors of varicose veins seem to be similar to that of other European countries. Regarding CEAP stages there are both similarities and differences without any specific tendency rule between the scattered data of various available studies. ^16,18,19,22