Cardiovascular Risk Factors in Patients with Erectile Dysfunction

While not lethal, erectile dysfunction (ED) can negatively affect the quality of life of patients. The objective of this study was to investigate cardiovascular risk factors (CRF) associated with ED, taking into account their sociodemographic characteristics. Possible correlations between the degree of ED and CRF were investigated. Fifty-six patients with ED, with ages ranging from 38 to 79 years (mean of 57.4 ± 8.4 years), with or without CRF were prospectively studied. ED was classified as mild, moderate or severe using the International Index of Erectile Function (IIEF). Demographic (age, marital status, number of children, education level and place of residence) and clinical data relating to CRF [high blood pressure (hypertension), diabetes, alcoholism, weight and smoking] were obtained by applying a questionnaire. Frequency tables were used to assess the association of the degree of ED with sociodemographic and clinical variables. Most patients were married (82.1%) had children (85.7%) and incomplete primary education (73.3%). Moreover, most participants had severe ED (75%), followed by moderate (17.9%) and mild (7.1%). Hypertension was the most common CRF (53.6%) followed by diabetes, obesity, alcohol consumption and smoking. No significant association was found when the mean age and body mass index were evaluated in respect to the degree of ED. Moreover, no significant correlation was found for the degree of ED in relation to hypertension, diabetes, smoking and alcohol consumption. Most hypertensive patients and nearly half of the smokers and ex-smokers had grade 3 ED. Grade 3 ED in this study may be related to the high frequency of concomitant CRF associated to ED however there was no significant association between ED in general and CRF.


Introduction
Erectile dysfunction (ED) is defined as the inability to achieve and sufficiently maintain penile erection for satisfactory sexual intercourse (National Institutes of Health, 1993). This dysfunction affects approximately 150 million men worldwide, but there is a projection that more than 300 million patients will be affected by 2025 (Hatzimouratidis et al., 2010). ED is considered an important public health problem with regard to unhealthy living habits (Abdo et al., 2006) that negatively influence the individual's self-esteem (Phé & Rouprêt, 2012).
About 40% of men with ED present with cardiovascular disease (Kawanishi et al., 2001;Solomon et al., 2003). Furthermore, it has been demonstrated that ED precedes the onset of cardiovascular disease (CVD) symptoms by approximately three years (Thompson et al., 2005); there is a 23% higher risk of death due to CVD in patients with ED (Hotaling et al., 2012 Patients were treated at the Urology Clinic of the teaching hospital of FAMERP. Subjects transferred to other clinics, presenting with morbid obesity or a physical disability and those who were under 18 years old were excluded. All patients complaining of ED were included after they completed a questionnaire on erectile function, the International Index of Erectile Function 5 (IIEF-5), which consists of five questions covering areas of male sexual function corresponding to the erection, orgasm and to sexual desire (Rosen et al., 1999). When the score of the IIEF-5 is between 17 and 24, the ED is classified as mild (grade 1), between 10 and 16, the ED is moderate (grade 2) and when less than 10 points the ED is considered severe (grade 3).
Sociodemographic data (age, marital status, number of children, education level and place of residence) and related clinical CRF [hypertension, diabetes, alcoholism, body mass index (BMI) and smoking] were obtained by applying a second questionnaire. Alcoholism was characterized in patients who drank alcoholic beverages every day.
All patients were weighed on digital weighing scales (Glass 6 FW G-Tech) and their height was measured using a tape measure. Weight was classified according to the BMI, which is calculated by dividing weight (in kilograms) by the square of the height (in meters). A BMI of from 18.5 to 24.9 kg/m 2 is considered normal weight, between 25.0 and 29.9 kg/m 2 is considered overweight, from 30.0 to 34.9 kg/m 2 is class 1 obesity, 35.0 to 39.5 kg/m 2 is class 2 obesity and a BMI of more than 40.0 kg/m 2 is classified as class 3 obesity.
Descriptive statistics (mean, standard deviation, median, minimum and maximum) were used for data analysis. Quantitative variables were compared using the t test for independent samples or the Kruskal-Wallis test (nonparametric). Frequency tables were used to identify any associations of the degree of ED (mild, moderate and severe) with sociodemographic (age, marital status, number of children, education level and place of residence) and CRF variables (hypertension, diabetes, alcohol consumption, BMI and smoking). All analyzes were performed using the R-64 computer software version 2.13.0 (The R Foundation for Statistical Computing, Auckland, New Zealand). The level of significance was set for an alpha error greater than 0.05.
The most frequent cardiovascular risk factor (Table  1) was hypertension (53.6%) and 44.6% of the patients with ED were obese. A total of 41.1% of the patients were smokers (8.9%) or ex-smokers (32.2%). Regarding age, Table 2 shows that the age ranged from 38.0 to 79.0 years, with a higher mean age for patients with grade 3 ED. There was no significant association between the mean age of patients and the degree of ED (p-value = 0.25) ( Table  3).  Table 4, the mean BMI of patients with grades 1 and 3 ED was classified as obesity class 1 (30.0 to 34.9 kg/m 2 ) while for patients with grade 2 ED, the mean BMI was considered overweight (25.0 to 29.9 kg/m 2 ). There was no significant association between the mean BMI and the degree of ED (p-value = 0.37) ( Table 5).  30.9 5.5 SD = standard deviation There was no significant association between the median number of children and the degree of ED (p-value = 0.99; Kruskal-Wallis test), with a median of 2.5 children both for patients with grades 1 and 2 ED and for those with grade 3 ED. Moreover there was no association between the degree of ED and having children or not (p-value = 1.0; Fisher's exact test).
No significant correlation was found in an analysis of the CRF (hypertension, diabetes, smoking and alcoholism) and ED (p-value > 0.05; Pearson chi-square) (Tables 6 and 7).

Discussion
The present study shows that the most common cardiovascular risk factor in patients with ED was hypertension; these results corroborate data in the literature (Spessoto et al., 2010;Spessoto, 2012). As elevated blood pressure is an independent and continuous risk factor for cardiovascular disease (Lewington et al., 2002), the data suggest that hypertension may influence the onset or worsening of ED.
About half (51.8%) of the patients with ED were also diabetics. This finding agrees with data reported in the literature, i.e., the prevalence of diabetes in patients varies between 35 and 85% ( In this study, 78.5% of patients were overweight, a result that substantiates data in the literature; Walczak et al. (2002) studied 154 men with ED and found that 79% were overweight. On investigating the impact of obesity on erectile function, Chung et al. (1999) analyzed the erectile capacity of 321 men with ED using Doppler ultrasound of the cavernous arteries of the penis. The authors concluded that the quality of erectile function was better in non-obese rather than in obese patients.
Regarding the degree of ED, 75% (n = 42) of patients had severe ED with the mean BMI of these patients being categorized as class 1 obesity. This finding is consistent with Veronelli et al. (2006) who, on using the IIEF questionnaire for patients aged 23 and 50, found that the degree of ED was worse in obese individuals.
In the current study, 41.1% of the patients with ED were smokers or former smokers. Several epidemiological studies have shown that smoking not only increases the risk of ED (Kupelian et al., 2007;Saigal et al., 2006), but also increases the risk be ED associated with other cardiovascular risk factors (hypertension, diabetes and dyslipidemia) or aging (Nicolosi et al. 2003;Bortolotti et al, 2001).
According to Santos et al. (2008), clinical and experimental studies have shown that ED induced by cigarette smoking is associated with a deficiency in penile blood flow and acute vasospasm of the penile arteries. Furthermore, long-term smoking has deleterious effects on the vascular endothelium and peripheral nerves and so not smoking reduces the risk of ED.
Regarding the degree of ED, 45.2% of patients with grade 3 were smokers or ex-smokers. On investigating 118 former smokers with ED, Pourmand et al. (2004) found that the clinical improvement one year after smoking cessation was lower in older patients and those with severe ED.
In this study, 42.9% of patients with ED were alcoholics. Lee  The influence of CRF such as obesity, hypertension, diabetes, smoking and alcohol on patients with ED requires further scientific research using larger sample sizes compared to this study. No statistically significant associations between ED and CRF were found in the current series, possibly due to the small number of patients studied.
Another relevant aspect is the clinical importance of the results, as they reinforce the need for a multidisciplinary approach to patients with ED who may have one or more CRF. This multidisciplinary team should include professionals in the fields of medicine, nutrition, physiotherapy, physical education and psychology. Further long-term clinical trials are needed to investigate ED as a marker of cardiovascular diseases.

Conclusion
There was a predominance of patients with ED in the sixth decade of life, most were married and with a low level of schooling. Hypertension was the most frequent CRF, followed by diabetes, obesity, alcohol consumption and smoking. Most patients with severe ED presented with hypertensive and nearly half were smokers or ex-smokers. Thus, severe ED may be related to the high frequency of concomitant CRF such as hypertension, obesity, smoking, diabetes and alcoholism. However, there was no significant association between ED in general and CRF.