Association of metabolic syndrome, atherosclerosis risk ... - Nature

International Journal of Impotence Research (2012) 24, 141 -- 146 & 2012 Macmillan Publishers Limited All rights reserved 0955-9930/12 www.nature.com/ijir

ORIGINAL ARTICLE

Association of metabolic syndrome, atherosclerosis risk factors, sex hormones in ED in aboriginal Taiwanese J-K Chao1,2, W-H Kuo3, H-S Chiang4,5, TI-S Hwang5,6, I-C Chao7 and S-K Chiang1,8 The overall prevalence of metabolic syndrome (MS) in aboriginal male Taiwanese is very high. Many studies have found that those with cardiovascular disease and MS have a significantly higher risk of ED. In this study, we attempted to find the correlation among MS risk factor, atherosclerosis risk factors and low serum testosterone in relation to the development of ED. This was a cross-sectional study of 238 cases, and collected data included demographic data, lifestyle questionnaires, sexual desire scale, sexual satisfaction scale and International Index of Erectile Function (IIEF) questionnaire. Among our 238 subjects, 146 had MS (61.3%) and 114 subjects with MS had ED (85.7%). Using age-adjusted multivariate logistic regressive analysis, this study showed that aboriginal males with ED had a significantly higher prevalence of MS (OR ¼ 12.02, 95% confidence intervals (CI): 6.33 -- 22.83, Po0.001). Among the MS components, abnormal fasting blood sugar was the most significantly independent factor for ED in aboriginal males (OR ¼ 8.94, 95% CI: 4.71 -- 16.97, Po0.001). The presence of MS had a significant correlation with lower IIEF-5 scores, lower sexual desire scores, lower testosterone serum level (Po0.01) and abnormal interleukin-6 (IL-6) and high sensitivity C-reactive protein (HsCRP). The results of this study support the idea that MS, low serum testosterone and HsCRP may predict ED in aboriginal Taiwanese males. Further studies with population-based and longitudinal design should be conducted to confirm this finding and design to compare rates of ED in aboriginal men with MS. International Journal of Impotence Research (2012) 24, 141 -- 146; doi:10.1038/ijir.2012.5; published online 12 April 2012 Keywords: atherosclerosis risk factors; ED; metabolic syndrome

INTRODUCTION The metabolic syndrome (MS) is a constellation of metabolic abnormalities associated with an increased risk of cardiovascular disease (CVD).1 MS is becoming a public health concern because its prevalence is rapidly increasing throughout the world, due to the increased incidence of an overweight condition or obesity and physical inactivity.2,3 In this context, it is now well established that MS is associated with ED and CVD. The overall prevalence of MS among aboriginal male Taiwanese was 50.3%; about two-thirds of the aborigines older than 20 years in southeastern Taiwan were either overweight or obese, and more than half of that population had MS.4 According to a 2007 study on the Department of Health, Executive Yuan, ROC (Taiwan) diagnostic criteria for MS, the proportion of aboriginal people with MS (83.3%) was much higher than that of Taiwanese (46.4%) and Hakka (40.6%), and showed more significant differences.5 Ko’s study pointed out that the life expectancy of the aborigines was 10 years less than that of the average person in the entire Taiwan population, and their standardized mortality ratio of heart disease and stroke was significantly higher.6 In aging Taiwanese males, the presence of MS is strongly associated with ED and abnormal fasting blood sugar, and is the most independent predictor for ED.7 Some epidemiological studies have also shown that type 2 diabetes 1

mellitus (DM) and MS can predict the development of male hypogonadism.8,9 Maggio’s study also reported that low serum testosterone levels are a risk factor for diabetes, MS, inflammation and dyslipidemia.10 Celermajer’s data suggest that endothelial dysfunction is considered an early marker for atherosclerosis, preceding angiographic or ultrasonic evidence of atherosclerotic plaque.11 Liu’s study showed that a substantial proportion of adult Taiwanese had androgen deficiency and symptomatic androgen deficiency, and the prevalence increased with age in Taiwanese men. He also pointed out that older age, obesity and DM were independent risk factors for androgen deficiency and symptomatic androgen deficiency.12 Strong evidence exists showing that MS is a major risk factor for ED, and that low levels of serum testosterone contribute to ED.8 -- 10,12 However, no evidence proved that whether the effects of MS are far-reaching enough to extend to aboriginal male erectile function. Until now, there are a few studies dealing with the impacts of MS on aboriginal male erectile function. The links between ED and MS and atherosclerosis risk factors suggest that ED may be a warning sign of poor health and a heightened risk of illness in aboriginal men. Thus, the aim of this study was to evaluate the prevalence of ED in aboriginal men with MS. We also attempted to find the correlation among risk factors of MS in

Department of Psychiatry, Yuli Veterans Hospital, Hualian, Taiwan, ROC; 2Department of Nursing, Chung Hwa University of Medical and Technology, Tainan County, Taiwan, ROC; Department of Medicine, Armed-Forces Hualien General Hospital, Hualien County, Taiwan, ROC; 4Department of Urology, Medical University Hospital, Taipei, Taiwan, ROC; 5 College of Medicine, Fu Jen Catholic University, Taipei, Taiwan, ROC; 6Division of Urology, Shin Kong Memorial Hospital, Taipei, Taiwan, ROC; 7Department of Medicine, Southeast University, Nanjing, Mainland, China and 8Department of Human Development, Tzu Chi University, Taiwan, ROC. Correspondence: Professor Shih-Kuang Chiang, Department of Human Development, Tzu Chi University, No.91, Xinxing St., Yuli Town, Hualian County 98142, Taiwan, ROC. E-mail: [email protected] Received 19 July 2011; revised 1 February 2012; accepted 8 March 2012; published online 12 April 2012 3

Metabolic syndrome with ED in aboriginal Taiwanese J-K Chao et al

142

aboriginal men, atherosclerosis risk factors and low serum testosterone in relation to the development of ED.

MATERIALS AND METHODS Subjects Subjects selected for this study were men aged over 40 years who took part in our community health examinations. These participants were older adults who had come from the local aboriginal community in eastern Taiwan. Participants were eligible if they could read and complete the questionnaire. Exclusion criteria were the use of any androgen therapy during the previous 3 months (7 months for implantable testosterone); any serious medical, psychiatric or neurological condition that could affect brain structure or cognition; a history of head trauma with loss of consciousness lasting more than 5 min; a current or past history of substance abuse or medication, such as antidepressants, that was likely to affect sexual function; or they were unwilling to complete the forms. Subjects who were asexual individuals were excluded from the study. A total of 275 participants were evaluated from March 2010 to January 2011, and 238 (86.2%) completed questionnaires were returned. A psychiatric doctor and relevant staff member from the psychiatry department examined the participants separately.

Ethical issues The study protocol was reviewed and approved by the Ethical Committees for Human Research at Yuli Veterans Hospital. Before each interview, the interviewer explained the objectives and methodology of the study to each participant, and signed the survey document when verbal informed consent was obtained from the participant. Participants were informed that the survey was anonymous. The staff distributed the questionnaire and informed the participants that completion of the questionnaire was voluntary and responses were anonymous.

Procedure The staff members interviewed the participants individually in a quiet room. Data were collected using self-reported questionnaires and inperson interviews. Participants were asked to complete the questionnaire and were offered a presentation on sexual behavior terms. A research assistant and doctors were available to answer any questions. After completing the questionnaire, the participants were asked to place it in the provided envelope and close it.

Assessment instrument Demographic questionnaire and sexual behavior scale. The questionnaire included 14 items, predominantly multiple-choice. There were 14 demographic and descriptive items, including the participant’s gender, relationship status, age, educational level, religion, smoking and drinking habits, CVD history, awareness of his/her health conditions, their relationship with a partner and so on. Data on demographics, and height and weight for body mass index (BMI) were gathered by the interviewers. BMI is a statistical measure of the weight scaled according to height, and is defined as the body weight of the individual divided by the square of their height. The Taiwanese obesity definition was used in this study. Overweight was defined as BMI X24 kg m2 and obesity was defined as BMI X27 kg m2 (refs 2,13,14). Abdominal obesity was defined as waist circumference X90 cm in men.

Sexual desire inventory (SDI). The Chinese-language version of the SDI (SDI-C) was translated and modified from Spector’s 14-item SDI.15,16 The SDI-C was used to construct the survey questionnaires. All 14 SDI-C items were categorized into three factors, based on the factor analysis results of Lee et al.16 These were solitary, dyadic and mixed factors; the latter was comprised of overlapping items that were extracted to form this third factor. Their fit results are P ¼ 0.68 and GFI ¼ 0.93 for the three-factor model. International Journal of Impotence Research (2012), 141 -- 146

The International Index of Erectile Function (IIEF). Patients with ED were defined as those who subjectively had been unable to achieve or maintain sufficient erection for sexual intercourse. The erectile function scale consists of questions one to five, and assesses global erectile function.17 Then all these subjects would receive IIEF assessments to confirm the diagnosis of ED and evaluate their severity of ED according to the total score of IIEF. Scoring of the IIEF allows classification of each patient as having no (score over 21), mild (12 -- 21), moderate (8 -- 11) or severe (p7) ED. Scores above 21 represent normal erectile function and scores at or below this cutoff represent ED. A high degree of internal consistency was observed for each of the five domains and for the total scale (Cronbach’s alpha values of 0.73 and higher and 0.91 and higher, respectively) in the populations studied. Men who did not complete the questionnaire were excluded from statistical analysis. Physical examination and blood profiles. Participant’s blood profiles were obtained after a 12-hour fast, and were sent for storage in a 70 1C refrigerator within 4 h of collection. Samples were sent to a hospital laboratory for analysis. Total testosterone (TT), free testosterone (FT), bioavailable testosterone (BioT), sex hormone-binding globulin, high sensitivity C-reactive protein (HsCRP) and interleukin-6 (IL-6) levels were measured using standard laboratory procedures. Biochemical markers such as high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), and fasting plasma glucose were analyzed using a biochemical autoanalyzer (Beckman Coulter, Lx-20, Brea, CA, USA) at the Clinical Laboratory, Department of YangKang Veterans Hospital. Fasting blood samples were obtained between 0800 and 1000 h to minimize diurnal variation. The serum levels of testosterone were measured with a solid-phase, competitive, chemiluminescent enzyme immunoassay (IMMULITE 2000 Total Testosterone, Diagnostic Products Corporation, Los Angeles, CA, USA) at baseline and at the end of the study. Sex hormone-binding globulin was measured separate from the total fraction of testosterone. Normal ranges for serum testosterone are 300 -- 1200 ng dl1 and for FT, X7 ng dl1 (ref 18). In this study, we used an age group of 40 to 70-year-old as the main sample, so low TT was defined as TT o300 ng dl1 and low FT was defined as FTo7 ng dl1. The FT level was calculated from TT, sex hormonebinding globulin and albumin, according to the Vermeulen formula.19 The Adult Treatment Panel III (ATP III) of the National Cholesterol Education Program modified for Asians defined MS as the presence of three or more of the following: fasting plasma glucose X110 mg dl1, serum TG X150 mg dl1, serum HDL-C o40 mg dl1 in men and o50 mg dl1 in women, blood pressure X130/85 mm Hg, or waist circumference 490 cm in men and 480 cm in women.20,21 Individuals diagnosed as previously having hypertension, DM or hyperlipidemia, but were under control with regular medication were also included. A smoker was defined as a person who smoked X10 cigarettes per day and had done so for more than 6 months, and a drinker was defined as someone who consumed alcohol every week and had done so for 6 consecutive months. Statistical analyses This study used SPSS Version 15.0. (SPSS, Chicago, IL, USA) statistical software to perform descriptive analysis and analysis of variance. Continuous variables were reported as mean±s.d. and categorical variables were reported as percentage (95% confidence intervals (CI)). Differences in proportions and means were assessed using a w2 test or t-test, and the means comparison of ED and MS under each categorical demographic variable (for example, age, education, sexual desire and IIEF total score) was examined using the Mann -- Whitney U (M -- W U) test. In addition, the Kruskal -- Wallis H test was used to test the relationship between participants who had both MS and ED and their educational level, age, TT serum level and sexual desire, and then we used M -- W U analysis to determinate post hoc results. We also used the w2 to test the relationship between the participant’s ED and MS, hypertension, DM and atherosclerosis risk factors, and binary erectile function was estimated by odds ratios with 95% CIs. The differences between the groups were considered & 2012 Macmillan Publishers Limited


143 significant if P values were lesser than 0.05. We also used MS, age, HsCRP and FT to run the logistic regression model for predictors of ED.

Table 1.

Socio-demographic characteristics of the study group N (N ¼ 238)

Percent (%)

Educational level p9 Years 49 Years

122 116

51.3 48.7

Testosterone Normal Abnormal

152 86

63.9 36.1

ED Yes No

133 105

55.9 44.1

MS Yes No

148 90

62.2 37.8

Drinking Yes No

142 96

59.6 40.4

Central obesity Yes No

177 61

74.4 25.6

Smoking Yes No

137 101

57.6 42.4

Hyperlipidemia Yes No

46 192

19.3 80.7

BMI o27 X27

112 126

47.1 52.9

Hypertension Yes No

98 140

41.2 58.8

Abnormal FBS Yes No

99 139

41.6 58.4

Characteristic

RESULTS In all, 38 of the original 276 aboriginal Taiwanese participants did not complete the tests and were excluded, leaving 238 samples (86.2%) for analysis. The mean±s.d. age of all study participants was 51.34±7.85 years (range 40 -- 70 years), and the average educational level was 10.05±3.07 years. Table 1 shows the sociodemographic and other characteristics of the study subjects. Of the 238 participants, 116 (48.7%) had graduated from junior high school, 126 (52.9%) were currently obese (BMI X27), 86 (36.1%) had a serum testosterone level below 300 ng dl1, 133 (55.9%) had ED, 137 (57.6%) were current smokers, 148 (62.2%) had MS, 98 (41.2%) had hypertension, 99 (41.6%) had DM, 46 (19.3%) had dyslipidemnia, 56 (23.5%) had abnormal IL-6 and 34 (14.3%) had abnormal HsCRP. Table 2 shows the relationship between ED and age, educational level, atherosclerosis risk factors, sex hormone and MS risk factors using the M -- W U test. As the data (age, educational level, IIEF total score, TT, SHGB, HsCRP, glucose and TG) were not in a normal distribution, we used the non-parametric M -- W U test to analyze them. Participants with ED had significantly lower serum levels of TT, FT and BioT than those without ED. We also found that participants without ED were significantly younger than those with ED. The data also showed participants with ED had significantly abnormal atherosclerosis risk factors (HDL-C, HsCRP and IL-6). Table 2 also shows data on the relationship between ED and central obesity, DM, hypertension and MS using the w2 test. The relationships between ED and central obesity (w2 ¼ 7.39, P value ¼ 0.007), DM (w2 ¼ 53.74, P value o0.001), hypertension (w2 ¼ 23.40, P value o0.001) and MS (w2 ¼ 70.98, P value o0.001) were significantly different. Table 3 lists data on the relationships between MS and sexual desire, testosterone, ED and atherosclerosis risk factors (HDL-C, TG, HsCRP and IL-6). Sexual desire total scores, dyadic and comparative factors, and IIEF scores were significantly lower among the subjects with MS than among those without. The TT, FT, BioT and HDL-C serum levels were higher among the subjects without MS than among those with MS, but TG and HsCRP serum levels were lower among the subjects without MS than among those with MS. In the w2 results we can see that the association between MS and ED was significant (w2 ¼ 70.98; Po0.001), and similarly the association with abnormal IL-6 (w2 ¼ 5.11; P ¼ 0.027). Table 4 shows that subjects were grouped in accordance with the number of MS components they had. The results showed that the greater the number of MS components, the higher the prevalence of ED and the higher the abnormal HsCRP and IL6 rate (Po0.05). The sexual desire scores, IIEF scores, TT, FT and BioT serum levels were significantly decreased with an increment in the MS components number (Po0.01). To evaluate the statistical effect of individual MS components, serum testosterone level and serum HsCRP on ED, the prevalence of ED was compared to the components of MS, serum testosterone level and serum HsCRP one by one. We found all of the variables had a significant impact on ED prevalence using univariate analysis (Table 5). After adjusting the ORs of age, the results of multivariate logistic regression analysis indicated significant ORs for MS (OR ¼ 12.02, 95% CI ¼ 6.33 -- 22.83, Po0.001), DM (OR ¼ 8.94, 95% CI ¼ 4.71 -- 16.97, Po0.001), HT (OR ¼ 3.60, 95% CI ¼ 2.01 -- 6.45, Po0.001), TG abnormal (OR ¼ 2.82, 95% CI ¼ 1.34 -- 5.92, P ¼ 0.006), HDL abnormal (OR ¼ 5.48, 95% CI ¼ 3.08 -- 9.76, Po0.001), WC abnormal (OR ¼ 2.30, 95% CI ¼ 1.26 -- 4.20, P ¼ 0.001), TT abnormal (OR ¼ 3.43, 95% CI ¼ 1.91 -6.16, Po0.001), FT abnormal (OR ¼ 3.93, 95% CI ¼ 2.26 -- 6.81, Po0.001), HsCRP abnormal (OR ¼ 16.08, 95% CI ¼ 3.74 -- 69.14, & 2012 Macmillan Publishers Limited

Abbreviations: BMI, body mass index; FBS, fasting blood sugar; MS, metabolic syndrome.

Po0.001) and IL-6 abnormal (OR ¼ 2.63, 95% CI ¼ 1.35 -- 5.11, P ¼ 0.004), respectively. Table 6 lists the factors related to ED in multiple logistic regression analysis. After adjusting for age, we used HsCRP, MS and FT to run the logistic regression model for predictors of ED, and the analysis showed that there was a significant difference for MS (OR ¼ 9.24, 95% CI ¼ 4.68 -- 18.22, Po0.001), abnormal HsCRP (OR ¼ 9.70, 95% CI ¼ 2.06 -- 45.76, P ¼ 0.004) and lower serum FT (OR ¼ 2.16, 95% CI ¼ 1.12 -- 4.16, P ¼ 0.021). We then used these variables to predict and set the cutoff point for the probability of 0.50, and the correctness of reclassification of 77.7%.

DISCUSSION The MS is composed of CV risk factors including increased BMI/ waist circumference, blood pressure, plasma glucose and TG, as well as decreased HDL-C. In this study, the aboriginal residents of eastern Taiwan, the research subjects, were divided into two groups: those with and without MS, respectively; we used atherosclerosis risk factors, MS component factors and serum International Journal of Impotence Research (2012), 141 -- 146


144 Table 2.

Relationship of ED and age, educational level, atherosclerosis risk factors, sex hormone and metabolic syndrome risk factors No ED (n ¼ 105)

ED (n ¼ 133)

Age Education level

50.02±7.75 10.18±3.01

52.38±7.79 9.94±3.12

IIEF total score BMI TT BioT FT SHBG HsCRP HDL-C TG FBS

23.32±1.21 27.05±3.68 440.19±176.62 184.13±59.14 7.65±2.43 42.15±18.10 0.15±0.21 41.69±10.94 204.86±124.80 110.19±45.57

16.63±4.64 27.75±4.36 358.70±179.54 147.76±58.32 6.21±2.36 40.98±20.37 0.55±0.78 35.34±10.04 218.60±129.24 129.91±76.013

Central obesity No Yes

36 (34.3) 69 (65.7)

25 (18.8) 108 (81.2)

DM No Yes

89 (84.8) 16 (15.2)

50 (37.6) 83 (62.4)

Hypertension No Yes

80 (76.2) 25 (23.8)

60 (45.1) 73 (54.9)

MS Normal Abnormal

71 (67.6) 34 (32.4)

19 (14.3) 114 (85.7)

IL-6 Normal Abnormal

90 (85.7) 15 (14.3)

92 (69.2) 41 (30.8)

MS

P value Sum

o0.001a,* o0.19 o0.001a,* o0.001* o0.001* 0.278a o0.001a,* o0.001* 0.317a 0.003a,* 0.007* w2 ¼ 7.39 o0.001b,* w2 ¼ 53.74 o0.001b,* w2 ¼ 23.40 o0.001b,* w2 ¼ 70.98

MS

P value Sum

No

Yes

(n ¼ 90)

(n ¼ 148)

43.70±18.48 7.00±7.56 25.41±11.33 11.29±4.30

34.36±20.00 5.46±6.44 20.01±11.66 9.06±5.19

o0.001* 0.361a 0.001* o0.001*

21.76±3.59 471.70±199.28 7.70±2.51 184.19±61.30 45.47±17.91 0.17±0.33

18.26±5.08 347.80±154.19 6.33±2.34 151.41±58.08 39.08±19.88 0.50±0.73

o0.001a,* o0.001a,* o0.001a,* o0.001a,* 0.001a,* o0.001a,*

ED No Yes

71 (78.9) 19 (21.1)

34 (23.0) 114 (77.0)


76 (84.4) 14 (15.6)

106 (71.6) 42 (28.4)

0.018a,* 0.637

Sexual desire Solitary Dyadic Comparative IIEF total score Total testosterone Free testosterone Bio testosterone SHBG HsCRP

o0.001b,* w2 ¼ 70.98 0.027b,* w2 ¼ 5.11

Abbreviations: HsCRP, high sensitivity C-reactive protein; IIEF, International Index of Erectile Function; IL-6, interleukin-6; MS, metabolic syndrome; SHBG, sex hormone-binding globulin. a Using Mann -- Whitney U test. b Using w2 test. *Significantly different (P-value o 0.05).

0.003b,* w2 ¼ 8.92

Abbreviations: BioT, bioavailable testosterone; BMI, body mass index; DM, diabetes mellitus; FBS, fasting blood sugar; FT, free testosterone; HsCRP, high sensitivity C-reactive protein; HDL-C, high-density lipoprotein cholesterol; IIEF, International Index of Erectile Function; IL-6, interleukin-6; MS, metabolic syndrome; SHBG, sex hormone-binding globulin; TG, triglycerides; TT, total testosterone. a Using Mann -- Whitney U test. b Using w2 test. *Significantly different (P-value o 0.05).

testosterone as related indicator risk factors of ED associated with MS. The average age of the subjects was 51.34±7.85 years, and the mean educational level was 10.05±3.07 years. This study found that 133 subjects had ED (55.9%) and 105 did not (44.1%), which is higher than in previous studies.22,23 In addition, there was a significant correlation between the subjects with ED and atherosclerosis risk factors, age, serum TT, FT, BioT and MS (Po0.05). Atherosclerosis risk factors This study showed that the aboriginal subjects with ED had higher HsCRP and lower HDL. Nehra’s24 report showed that ED and CVD share common risk factors, but also expected them to have a common pathophysiological pathway. Chew’s25 data suggest that ED is not only significantly associated with but is also strongly predictive of subsequent atherosclerotic CV events. This is even more striking when ED presents at a younger age. MS This study shows that the proportion of aboriginal participants who had a history of diabetes, hypertension, hyperlipidemia and International Journal of Impotence Research (2012), 141 -- 146

Table 3. The relationship of metabolic syndrome, sexual desire, serum testosterone level, ED and atherosclerosis risk factors

MS, and these aboriginal participants who had high prevalence of ED6 Al-Hunayan et al.26 pointed out that ED usually occurs in middle-aged men, especially in those with diabetes---a finding similar to our results. Another study found that patients with hypertension have a lower serum testosterone level, which explains the development of ED in hypertensive patients;27 these results are similar to those of this study. Sex hormone Our results also showed that the TT, FT and BioT serum levels in aboriginal patients with ED were lower than in those without ED. TT, BioT and FT levels in patients with MS were lower than in those without MS, and the reduction of testosterone levels was associated with DM and MS. An epidemiological study has reported that a low testosterone concentration in type 2 DM is an independent risk factor, and even FT and BioT are associated with diabetes and obesity.28 ED This study shows that the aboriginal participants with a history of DM, hypertension, hyperlipidemia and MS had a significantly higher proportion of ED than the normal population. This result is similar to that in the Al-Hunayan study, which found that ED usually occurs in middle-aged men, especially in those with diabetes.26 Our results also showed that MS, abnormal FT and HsCRP were significantly related to erectile function, similar to the Grover et al.29 finding. There are some limitations to this study. First, our data was obtained from community-dwelling men participating in a free community health screening. Although the screening was open to the general male population, some selection bias may exist. Second, this was a cross-sectional analysis, and therefore causality cannot be determined and the participant’s prior sexual & 2012 Macmillan Publishers Limited


145 Table 4.

The prevalence of ED, age, sexual desire, sex hormones and atherosclerosis risk factors in relation to the number of MS components MS components no. A ¼ 0 -- 2 (n ¼ 94)

B ¼ 3 (n ¼ 63)

C ¼ 4 -- 5 (n ¼ 81)

P-value

Age

49.42±7.58

51.09±8.96

51.57±7.81

0.078

Sexual desire Post hoc Solitary Dyadic Post hoc Comparative Post hoc

43.28±18.40 A4B, C 6.94±7.54 25.09±11.32 A4B 11.19±4.28 A4B, C

32.32±21.15

35.98±19.33

0.002*

6.96±7.55 18.65±12.46

6.43±7.16 20.94±11.27

0.695a 0.002*

8.40±5.68

9.82±5.04

0.002*

21.64±3.58 A4B4C 468.45±196.52 A4B, C 45.02±17.80 184.52±61.90 A4B, C 7.72±2.52 A4B, C

18.89±5.51

17.74±4.80

o0.001a,*

362.83±168.02

333.77±144.49

o0.001a,*

38.65±16.56 157.38±59.82

39.62±22.51 144.76±54.76

0.073a o0.001a,*

6.65±2.60

5.99±2.02

o0.001a,*

IIEF Post TT Post SHBG BioT Post FT Post

hoc hoc

hoc hoc

HsCRP Normal Abnormal

90 (95.7) 4 (4.3)

53 (84.1) 10 (15.9)

61 (75.3) 20 (24.7)

ED No Yes

72 (76.6) 22 (23.4)

22 (34.9) 41 (65.1)

11 (13.6) 70 (86.4)


80 (85.1) 14 (14.9)

43 (68.3) 20 (31.7

59 (72.8) 22 (27.2)

0.001* w2 ¼ 15.02 o0.001* w2 ¼ 73.02

0.032 w2 ¼ 6.85

Abbreviations: BioT, bioavailable testosterone; FT, free testosterone; HsCRP, high sensitivity C-reactive protein; IIEF, International Index of Erectile Function; IL-6, interleukin-6; MS, metabolic syndrome; SHBG, sex hormone-binding globulin; TT, total testosterone. A ¼ MS components no. 0 -- 2; B ¼ MS components no. 3; C ¼ MS components no. 4 -- 5. a Using Kruskal -- Wallis H test. *Significantly different (P-value o 0.05).

Table 5.

Mutivariate logistic regressive analysis of Mets components, sex hormone and atherosclerosis risk factors for ED 95% CI for OR

Variable MS FBS abnormal HT TG abnormal HDL abnormal WC abnormal TT abnormal FT abnormal HsCRP abnormal IL-6 abnormal

Co-efficient

s.e.

Wald w2 value

P-value

Odds ratio

Lower limit

Upper limit

2.49 2.19 1.28 1.04 1.70 0.83 1.23 1.37 2.78 0.97

0.33 0.33 0.30 0.38 0.29 0.31 0.30 0.28 0.74 0.34

57.66 44.94 18.48 7.51 33.49 7.37 17.07 23.60 13.94 8.10

o0.001* o0.001* o0.001* 0.006 o0.001* 0.007 o0.001* o0.001* o0.001* 0.004

12.02 8.94 3.60 2.82 5.48 2.30 3.43 3.93 16.08 2.63

6.33 4.71 2.01 1.34 3.08 1.26 1.91 2.26 3.74 1.35

22.83 16.97 6.45 5.92 9.76 4.20 6.16 6.81 69.14 5.11

Abbreviations: FT, free testosterone; HDL, high-density lipoprotein; HsCRP, high sensitivity C-reactive protein; IL-6, interleukin-6; MS, metabolic syndrome; TG, triglyceride; TT, total testosterone. *Po0.01.

functioning cannot be incorporated into our models. Third, bias introduced by under-reporting is possible, as sexual behavior is a sensitive issue and the topic may be considered socially unacceptable in mainly ethnic Chinese cultural settings.30 Four, the data may be biased because the questionnaire was selfreported, and 13.8% of participants did not complete the survey or the whole course of testing. However, by ensuring privacy during the completion of the questionnaires and using an & 2012 Macmillan Publishers Limited

anonymous self-administered survey, an attempt was made to minimize this bias. Our participants were able to complete the study questions using multiple modalities (telephone, touch screen computers and internet). Future studies exploring sexuality in mid-life should include both biological and social factors. Finally, in this study, participants were all aboriginal Taiwanese males. There were no matched non-aboriginal male to be included. Thus, our data could not verify in a given degree of International Journal of Impotence Research (2012), 141 -- 146


146 Table 6.

Logistic regression model of predictors of ED 95% CI for OR

Variable Constant MS FT abnormal HsCRP Age

Co-efficient

s.e.

Wald w2 value

P-value

Odds ratio

Lower limit

Upper limit

2.12 2.22 0.77 2.27 0.008

1.08 0.35 0.33 0.79 0.021

3.82 41.12 5.31 8.23 0.13

0.051 0.000* 0.021* 0.004* 0.72

0.12 9.24 2.16 9.70 1.01

4.68 1.12 2.06 0.97

18.22 4.16 45.76 1.05

Abbreviations: FT, free testosterone; HsCRP, high sensitivity C-reactive protein; MS, metabolic syndrome. *Po0.01.

metabolic disturbance whether an aboriginal man have a greater risk of ED than a non-aboriginal man. Future studies should include both aboriginal and non-aboriginal participants. CONCLUSION The paper provides a survey of MS and ED in aboriginal Taiwanese. The results and conclusion are of significant interest, as the study both supports the idea of the close relationship between MS, atherosclerosis risk factors, sex hormone and ED, and also shows that MS, abnormal FT and HsCRP may predict ED in aboriginal Taiwanese. Moreover, the statement that MS and abnormal sex hormones in aboriginal Taiwanese may provide warning signs and should be the focus of physicians’ attention with respect to ED and CVD prophylaxis is very important. Further studies with population-based and longitudinal design should be conducted to confirm these findings and designed to compare rates of ED in aboriginal and non-aboriginal men with MS. CONFLICT OF INTEREST The authors declare no conflict of interest.

ACKNOWLEDGEMENTS This study was supported by a grant from the Yuli Veterans Hospital, Taiwan (VHYL99-02). We also wish to thank the psychiatric staff for their help in this study.

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