Lower Limb Varicose Veins among Nurses: A Single Center Cross-Sectional Study in Mansoura, Egypt

Abstract

Background:

Lower limb varicose veins are common among nurses due to occupational and nonoccupational risk factors.

Aims:

To estimate the prevalence of lower limbs varicosity and its associated risk factors.

Settings and Design:

A cross-sectional descriptive study was carried out among 201 nurses at Mansoura University Hospital from January 1^st to May 31^st, 2018.

Methods:

A questionnaire was used to collect sociodemographic data, risk factors for varicose veins, and occupational details. Varicose veins were diagnosed by Doppler ultrasound.

Statistical Analysis:

Univariate and logistic regression analyses were done.

Results:

The prevalence of varicose veins was 18.4%. Significant independent predictors are being ≥25 years old, working in emergency rooms and ICU/operative rooms, and using oral contraceptives with adjusted odds ratios [95% Confidence Interval (CI)] of [8.7 (2.6–28.4)], [10.8 (2.6–45.9)], [16.2 (3.9–67.4)], and [4.2 (1.3–13.2)], respectively.

Conclusions:

Independent predictors, other than age, are modifiable and those with highest AOR are occupationally related.

INTRODUCTION

Lower-limb varicose veins (VVs) are relatively common, with a worldwide reported prevalence ranging between 10% and 30%.[1,2] VVs are due to venous valves insufficiency, with age as an aggravating and risk factor and family history as an important risk factor.[3] Other risk factors include female sex, number of children given birth, body weight, constipation, and history of venous thrombosis.[3,4,5,6] Prolonged standing or walking at work has been suggested to be a cause of VVs.[7,8,9] Kind of job and body posture during work are among main risk factors for varicose veins.[10] Nurses are at higher risk of developing varicose veins because of the nature of their job which requires prolonged standing at patient bedside and this increases their risk of getting varicose vein later. Also, the majority of nurses are female nationwide and internationally.[11] VVs can jeopardize working output and old age health and cause other serious complications such as thrombotic problems.[12] Among different jobs, nursing needs high mobility, long time standing, and tiring physical positions that are necessary for performing nursing duty.[10]

Although the strong relationship between the development of lower limb varicosities and nature of work, to the best of the authors’ knowledge, no studies have investigated this vascular affection of nurses as a result of their workplace occupational exposure in Mansoura city.

This study was carried out among nurses at Mansoura University Hospital to estimate the prevalence of varicosity of the lower limbs and its possible associated risk factors among nurses in Mansoura University Hospital.

METHODS

This cross-sectional descriptive study was carried out in Mansoura University Hospital during the period from January 1^st to May 31^st, 2018. This is a tertiary care hospital affiliated to Mansoura University, Egypt with a total bed capacity of 1512 beds.

Target population

Nurses in Mansoura University Hospital (Main Hospital) employed for one year or more.

Sample size calculation

The sample size was calculated using Medcalc 15.8 (https://www.medcalc.org/). The primary outcome of interest is the prevalence of varicose veins as detected by Doppler ultrasonography. A pilot study revealed that six out of 30 nurses (20%) have varicose veins. With alpha error = 0.05, study power = 0.80, and 5% precision then the sample size is at least 194.

Sampling method

The total number of nurses on duty at the time of study was 2085. A systematic random sample was selected from the list of nurses (every 10^th). The selected nurses (208) were approached and requested to participate in the study and 201 (response rate of 96.6%) completed the questionnaire and Doppler examination.

Ethical approval

The study was approved by Mansoura Faculty of Medicine Institutional Research Board “MFM-IRB”. (Registration No. of the study: R.19.04.487).

Informed consent

Nurses gave informed consent to participate voluntarily in the study, before the interview, with a full right to withdraw and with assurance of confidentiality and anonymity of the data.

Study tools

A questionnaire was used to collect the following data: subjects’ characteristics, e.g., sex, age, smoking, exercise; past medical history and family history; risk factors for VVs, e.g., pregnancy, use of oral contraceptives, history of trauma or injury to the lower limbs; and occupational risk factors, e.g., number of daily working hours, static standing, walking, and sitting position, duration of employment, and department. Exercise was operationally defined as any bodily movement performed in order to develop or maintain physical fitness and overall health.[13]

Weight and height were measured then body mass index (BMI) was calculated by dividing a person’s weight in kilograms by the square of height in meters (kg/m²). Obesity is defined as BMI greater than or equal to 30.[14] All nurses were referred to Radiology Department to be investigated by Doppler ultrasonography (Toshiba, Xario 100, Japan) for the diagnosis of varicose veins according to National Institute for Health and Care Excellence (NICE) clinical guideline.[15]

Data analysis

Data were analyzed using SPSS version 16. Variables were described as numbers and percentage. Chi-squared test was used for comparison between groups and crude odds ratios (COR) were calculated. Significant predictors of lower limb varicosity in bivariate analysis (age, marital status, exercise, obesity, workplace, duration of work, daily working hours, static standing, chronic constipation, OCP use, and gravidity) were entered into a multivariate logistic regression using the forward Wald method and adjusted odds ratios (AOR) were calculated. P ≤ 0.05 was considered to be statistically significant.

RESULTS

Doppler ultrasonography revealed that 18.4% (37 out of 201) nurses have lower limb varicosities. Bilateral varicosities represented 5.5% while unilateral affection was 12.9% (26 nurses, of which 14 nurses had right limb varicosities and 12 had left limb varicosities; data are not shown in tables).

Table 1 shows that nearly equal percentage of nurses were below and more than 25 years old, most of them (84.1%) were female, more than half (56.7%) were married, nearly two-thirds were rural residents and not practicing exercise, and only 23.4% were obese. Varicose veins are significantly more prevalent among nurses aged ≥25 years, married, not exercising, and obese.

Table 1.

Prevalence of VVs and its variation according to demographic, obesity, and exercise of nurses

	Total n (%)#	VVs n (%)	Chi-square test	P	COR (95% CI)
Overall	201	37 (18.4)
Age: (years)
<25	100 (49.8)	5 (5.0)	23.8	≤0.001	1(r)
25 and more	101 (50.3)	32 (31.7)			8.8 (3.2-23.8)
Sex:
Male	32 (15.9)	5 (15.6)	0.2	0.7	1(r)
Female	169 (84.1)	32 (18.9)			1.3 (0.5-3.5)
Marital status:					1 (r)
Single	87 (43.3)	6 (6.9)	13.5	≤0.001	5.0 (2.0-12.7)
Married	114 (56.7)	31 (27.2)
Residence:					1 (r)
Rural	140 (69.7)	27 (19.3)	0.2	0.6	0.8 (0.4-1.8)
Urban	61 (30.4)	10 (16.4)
Exercise:					1 (r)
Yes	74 (36.8)	7 (9.5)	6.2	<0.001	3.0 (1.2-7.1)
No	127(63.2)	30 (23.6)
Obesity:					1 (r)
No	154 (76.6)	19 (12.3)	16.2	≤0.001	4.4 (2.1-9.4)
Yes	47 (23.4)	18 (38.3)

COR: Crude Odds Ratio. r: Reference group. N.B. Only 4 males without VV were smokers. ^#Column percent

The prevalence of VVs is significantly higher among nurses in emergency and ICU/operative rooms, working for ≥5 years, with more than 6 daily working hours, and with static standing posture (COR = 5.4, 4.1, 5.5, 2.5, 2.6; respectively). Varicosities are significantly higher among nurses having chronic constipation, using oral contraceptives, and those with three or more pregnancies (COR = 3.4, 2.8, 7.9; respectively) [Table 2].

Table 2.

Variation of VVs prevalence according to occupational and clinical data of nurses

	Total	VVs n (%)	Chi-square test	P	COR (95% CI)
Occupational data
Workplace:
Inpatient wards/outpatients	73	5 (6.9)			1 (r)
Emergency rooms	42	12 (28.6)	10	0.002	5.4 (1.8-16.8)
ICU/operative rooms	86	20 (23.3)	8	0.005	4.1 (1.5-11.6)
Duration of work:
<5 years	131	12 (9.2)	21.4		1 (r)
5 years and more	70	25 (35.7)		<0.001	5.5 (2.6-11.9)
Daily working hours:
up to 6 hours	124	16 (12.9)	6.5		1 (r)
>6 hours	77	21 (27.3)		0.011	2.5 (1.2-5.2)
Static standing:
No	156	23 (14.7)	6.2		1 (r)
Yes	45	14 (31.1)		0.013	2.6 (1.2-5.6)
Lift loads:
Never	73	14 (19.2)	0.2		1 (r)
Occasional	68	11 (16.2)	0.01	0.6	0.8 (0.3-1.9)
Usual/common	60	12 (20.0)		0.9	1.1 (0.4-2.5)
Medical history
Family history of varicose vein:
No	121	18 (14.9)	2.5		1 (r)
Yes	80	19 (23.8)		0.1	1.8 (0.9-3.7)
Chronic constipation:	178	27 (15.2)			1 (r)
No	28	10 (35.7)			3.1 (1.3-7.5)
Yes			6.9	0.008
Lower limb trauma/injury:					1 (r)
No	170	28 (16.5)	2.8		2.1 (0.9-5.0)
Yes	31	9 (29.0)		0.1
OCP use*:					1 (r)
No	117	16 (13.7)	6.9		2.8 (1.3-6.2)
Yes	52	16 (30.8)		0.01
Gravidity*:
None	75	9 (12.0)	0.2		1 (r)
1 and 2	69	10 (14.5)	17.5	0.7	1.2 (0.5-3.3)
3 and more	25	13 (52.0)		<0.001	7.9 (2.8-22.7)

*Females only. COR: Crude Odds Ratio. r: Reference group. OCP: Oral Contraceptive

The significant independent predictors of VVs among nurses are being ≥25 years old, working in emergency rooms and ICU/operative rooms, and using oral contraceptives with adjusted odds ratios (AOR) [95% Confidence Interval (CI)] of [8.7 (2.6–28.4)], [10.8 (2.6–45.9)], [16.2 (3.9–67.4)], and [4.2 (1.3–13.2)], respectively [Table 3].

Table 3.

Multivariate logistic regression analysis of independent predictors of VVs

	β	P	AOR (95%CI)
Age (years):
<25	-		1 (r)
25 and more	2.2	≤0.001	8.7 (2.6-28.4)
Workplace:
Inpatient wards/outpatients	-		1 (r)
Emergency rooms	2.4	0.001	10.8 (2.6-45.9)
ICU/operative rooms	2.8	≤0.001	16.2 (3.9-67.4)
OCP use*:
No	-		1 (r)
Yes	1.4	0.015	4.2 (1.3-13.2)
Constant	-5.9
Model χ	χ2=65.6, P≤0.001
Percent correctly predicted	87.6%

*Females only. AOR: Adjusted Odds Ratio. r: Reference group. OCP: Oral Contraceptive. N.B. The model included (age, marital status, exercise, obesity, workplace, duration of work, daily working hours, static standing, chronic constipation, OCP use, and gravidity) which were the significant predictors in univariate analysis

DISCUSSION

Varicose vein of the lower limbs is considered as the most common vascular disorder in humans, leading to serious signs and symptoms in affected persons and sometimes leads to surgical treatments and widespread morbidity.[16,17] Varicose veins are known to be more common among many professions including nurses who have to stand for a longer time during their work.[11]

The prevalence of lower limb VVs in this study is 18.4%. A similar rate (16.2%) was observed in the Republic of Korea.[18] A slightly higher prevalence (24.17%) was found in India;[11] however, a much higher prevalence (72.4%), with different degrees, was reported in Iran.[12] This difference could be due to different diagnostic approaches based on clinical finding using Clinical-Etiology-Anatomy-Pathophysiology (CEAP) standards or could be due to different durations of employment and working hours.

Studied nurses were nearly equal percentage below and more than 25 years old, most of them were female, more than half were married, nearly two-thirds were rural residents and not practicing exercise, and only 23.4% were obese.

Varicose veins in this study are more prevalent among older married female nurses, rural residents, not performing exercise, and obese with significant association except for sex and residence. Similarly, in Korea, statistically significant factors were age, pregnancy, and delivery; however, sex dependent difference was not verified.[18] Also, in India, the prevalence was slightly higher among female nurses than male and in older age group.[11]

In accordance with these results, in East China, nurses with advanced age (OR = 5.5, 95% CI: 4.22–7.2), married with childbearing (OR = 5.2, 95%CI: 3.97–7.04), low level of education (OR = 1.6, 95% CI: 1.22–1.99), and with family history of VVs had a greatly higher risk of varicose veins (OR = 1.8, 95% CI: 1.4–2.28).[19] Similar results were reported from Iran where being women, older ages, higher BMI, and family history were predictors for both presence and intensity of leg varicose veins.[12]

In the current study, VVs are significantly higher among nurses in emergency and ICU/operative rooms, more than 5 years of employment, working >6 hours daily, in static standing posture, having chronic constipation, using oral contraceptives, and those with three or more pregnancies.

These results are in agreement with a Korean study where VVs were significantly higher in the outpatient clinic and operating room, but not the emergency room and ICU which may be attributable to their high job transfer rate. Nurses with ≥4 hours of standing showed significantly higher prevalence[18] which coincided with previous studies showing that VVs incidence is associated with working hours in a standing position.[7,8,9,12,20,21]

The biological basis for the standing hypothesis is the impeded blood flow and consecutive stasis in veins of the lower extremities because of increased intravascular hydrostatic pressure in an upright working position. Stasis in the venous system is a key mechanism in venous vascular disease.[8]

Chronic constipation is associated with straining during defecation which could increase the intra-abdominal pressure that may lead to valvular incompetence or loaded colon could press the pelvic veins and obstruct venous return.

Similarly in Iran, long years of service, not exercising, irregular bowel movement, sitting and standing long hours, and overtime work were risk factors for the presence and intensity of leg VVs.[12] In accordance with these results, in East China, nurses with long service time and multiple night shifts had a greatly higher risk.[19] In India also, having ≥6 years of work experience, having >8 hours duty per day, with more hours of standing at work, positive family history, and with 3 or more childbirths appeared to be significant predictors. Nevertheless, constipation, habits of smoking and drinking alcohol, and oral contraceptive (OCP) use in female nurses did not appear to be significant risk factors.[11]

Pregnant workers are at an increased risk of VVs due to some interaction of pregnancy-related and work-related factors as both conditions increase intravascular venous pressure (in the case of pregnancy, due to increased pressure on the abdominal veins into which the leg veins drain; in the case of standing, because of increased hydrostatic pressure).[8]

In the present study, the significant independent predictors of VVs among nurses are being ≥25 years old, working in emergency rooms and ICU/operative rooms, and using oral contraceptives. Similarly, in East China, advancing age (AOR = 1.32, 95%CI: 1.2–1.5) and standing time (AOR = 1.7, 95%CI: 1.21–2.4) were independent predictors for VVs.[19] Coinciding with these results, in Japan, it was confirmed that prolonged upright standing at work, greater BMI, female sex, and age were significant independent predictors.[21] The correlation between the varicose intensity and increasing age is probably because of the enhanced pressure of surface veins resulting from leg muscle weakness and vascular wall damages following aging.[3]

The study from Korea was in agreement where working in outpatient clinic and operating room was significantly associated with VVs prevalence after adjustment for sociodemographic factors. However, the emergency room and intensive care unit did not differ significantly which may be attributable to the high job transfer rate and the regular provision of compression stockings by the hospital to these high-risk groups.[18]

Correspondingly, in Iran, multivariate analyses showed that standing for more than 4 hours had at least a 2 to 3 risk of developing leg VVs (with higher intensity), and per hour increase in overtime work had a 1%–2% increased risk.[12]

The etiology of varicose veins is multifactorial and may include: increased intravenous pressure caused by prolonged standing; increased intra-abdominal pressure arising from tumor, pregnancy, obesity, or chronic constipation; familial and congenital factors.[22] The intensity of varicosity increases with advancing age or long years of employment which is probably due to enhanced pressure of surface veins resulting from leg muscle weakness and vascular wall damages following aging.[3]

In nursing profession, nurses have to stand for a long time with both legs bearing weight, and most of them are female, so that they are at greatly increasing risk of varicose veins, whose incidence is 60% higher than the general population.[23] In addition to nurses, VVs are known to be more common among professions such as policemen, teachers, shopkeepers, and bus conductors who have to stand for longer time during their duties.[11]

Study strengths

A high response rate of participants together with the diagnosis of lower limb varicose veins using Doppler ultrasound is an important feature of this study.

Study limitations

This study has some limitations. This single center study is cross-sectional, hence, cannot prove cause-and-effect relationships with a relatively small sample size. No detailed study of working conditions had been investigated.

CONCLUSIONS

The prevalence of lower limb VVs is 18.4% among nurses. Advancing age, working in emergency rooms and ICU/operative rooms, and using oral contraceptives are associated with an increased risk. These independent predictors other than age are modifiable and those with highest AOR are occupationally related. Therefore, VVs might be prevented by the provision of nurses with anti-VVs measures (e.g., compression stockings and taking breaks) and scheduling job rotation, especially at high-risk departments to avoid long duration of standing work posture, and education of nurses regarding lifestyle modification, e.g., regular exercise and weight reduction, and rational use of OCPs.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.