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American Journal of Epidemiology Advance Access originally published online on July 10, 2007
American Journal of Epidemiology 2007 166(7):803-809; doi:10.1093/aje/kwm154
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American Journal of Epidemiology © The Author 2007. Published by the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org.

ORIGINAL CONTRIBUTIONS

Cigarette Smoking and Erectile Dysfunction among Chinese Men without Clinical Vascular Disease

Jiang He1,2, Kristi Reynolds1, Jing Chen2, Chung-Shiuan Chen1, Xigui Wu3, Xiufang Duan3, Robert Reynolds4, Lydia A. Bazzano1,2, Paul K. Whelton1,2 and Dongfeng Gu3

1 Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA
2 Department of Medicine, Tulane University School of Medicine, New Orleans, LA
3 Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
4 Pfizer, Inc., New York, NY

Correspondence to Dr. Jiang He, Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, 1430 Tulane Avenue, SL18, New Orleans, LA 70112 (e-mail: jhe{at}tulane.edu).

Received for publication November 2, 2006. Accepted for publication April 23, 2007.


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 References
 
The authors examined the association between cigarette smoking and risk of erectile dysfunction among 7,684 Chinese men aged 35–74 years without clinical vascular disease. Cigarette smoking and erectile dysfunction were assessed by questionnaire. Vascular risk factors were measured according to standard methods. After adjustment for age, education, alcohol consumption, physical inactivity, diabetes, hypertension, overweight, and hypercholesterolemia, the odds ratio of erectile dysfunction was 1.41 (95% confidence interval (CI): 1.09, 1.81) for cigarette smokers compared with never smokers. There was a statistically significant dose-response relation between cigarette smoking and risk of erectile dysfunction (ptrend = 0.005). Multivariate-adjusted odds ratios of erectile dysfunction were 1.27 (95% CI: 0.91, 1.77), 1.45 (95% CI: 1.08, 1.95), and 1.65 (95% CI: 1.08, 2.50) for those who smoked 1–10, 11–20, and more than 20 cigarettes per day, respectively, compared with never smokers. The association was stronger in participants with diabetes (odds ratio = 3.29, 95% CI: 1.49, 7.27) than in participants without diabetes (odds ratio = 1.33, 95% CI: 1.03, 1.73). If the association is causal, an estimated 22.7% of erectile dysfunction cases (11.8 million cases) among Chinese men are attributable to cigarette smoking. This 2000–2001 study of Chinese men documented an independent and dose-response relation between cigarette smoking and risk of erectile dysfunction.

China; impotence; men; risk factors; smoking

Abbreviations: CI, confidence interval; InterASIA, International Collaborative Study of Cardiovascular Disease in Asia


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 References
 
Cigarette smoking is a major cause of cardiovascular disease, cancer, stroke, lung disease, and premature death (1). Despite the serious health hazards, cigarette smoking is still very prevalent throughout the world, especially among men (2–4). More troublesome, recent data have suggested that the prevalence of cigarette smoking is increasing in teenagers and young adults (4–6). Further investigation into the adverse effects of cigarette smoking on health, especially those consequences related to young adults, is very valuable for targeting primary prevention efforts of cigarette smoking in youth. In 2000, 60.2 percent (147 million) of men and 6.9 percent (16 million) of women aged 35–74 years in China were current smokers (3). As the world's largest producer and consumer of tobacco products, China bears a substantial burden from smoking-related health consequences.

Several (7–14), but not all (15, 16), epidemiologic studies have suggested that cigarette smoking is related to increased risk of erectile dysfunction in men. Many of these studies, however, were conducted among patients with established atherosclerotic vascular disease (11, 13, 15, 17). Atherosclerotic vascular disease and its risk factors, including diabetes, hypertension, and hypercholesterolemia, are major underlying risk factors for erectile dysfunction (18, 19). The major cardiovascular disease risk factors were not measured and not adjusted for in previous studies (7–17). Furthermore, many of the previous studies had other methodological limitations, such as use of convenience samples (8, 12, 20–22), small sample size (20), or lack of a control group (22). We examined the association between cigarette smoking and risk of erectile dysfunction among 7,684 Chinese men aged 35–74 years who did not have a history of clinical vascular disease.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 References
 
Study population
The International Collaborative Study of Cardiovascular Disease in Asia (InterASIA) used a four-stage stratified sampling method to select a nationally representative sample of the general population aged 35–74 years in China. The sampling process was stratified by rural versus urban areas and north versus south. The final stage of sampling was stratified by age (10 years) and gender. Only one participant was selected from each household, without replacement.

A total of 9,359 men were randomly selected from 20 primary sampling units (street districts in urban areas or townships in rural areas) and invited to participate. A total of 7,684 men completed the survey and examination with a response rate of 82.1 percent. The analysis reported in this paper was restricted to the 4,763 men who answered "yes" to the question "Have you had sexual relations during the past 6 months?" and who did not have clinical coronary heart disease, stroke, or peripheral artery disease. The prevalence of cigarette smoking was 69.8 percent (62.0 percent of men aged 35–44 years, 72.6 percent of men aged 45–54 years, 74.1 percent of men aged 55–64 years, and 69.0 percent of men aged 65–74 years) among those who answered "no" to the question "Have you had sexual relations during the past 6 months?"

The Institutional Review Board at the Tulane University Health Sciences Center and ethics committees and other relevant regulatory bodies in China approved the InterASIA study. Informed consent was obtained from each participant prior to data collection.

Measurements
Data collection was conducted in examination centers at local health stations or community clinics in the participants' residential area. During the clinic visits, trained research staff administered a standard questionnaire including questions on demographic information, history of cardiovascular disease, lifestyle risk factors, and sexual behavior. The study participants who reported sexual relations during the preceding 6 months were asked to choose one of four possible answers to the question "How would you describe yourself?": "always or almost always; usually; sometimes; or never capable of having and maintaining a satisfactory erection for sexual relations." The subjects answering "always or almost always" were classified as normal, and those answering "usually," "sometimes," or "never" were classified as having "mild," "moderate," or "complete" erectile dysfunction, respectively. In the current analyses, erectile dysfunction was defined as "sometimes" or "never" being able to maintain a satisfactory erection during sexual relations. This single self-assessment question was developed on the basis of the National Institutes of Health criterion for erectile dysfunction: "the inability to achieve or maintain an erection sufficient for satisfactory sexual performance" (23, p. 84). This single question has been validated against the International Index of Erectile Function (24) and used in epidemiology studies among populations around the world (9, 25, 26). Information about current and former cigarette smoking was obtained by use of the lifetime smoking questionnaire from the National Health and Nutrition Examination Survey (27). Participants were defined as current smokers if they were smoking at the time of the survey and had smoked more than 100 cigarettes in their lifetime and classified as former smokers if they smoked more than 100 cigarettes in their lifetime but were not current smokers. The questionnaire was translated into Chinese and back-translated into English independently by investigators who were fluent in both Chinese and English.

During the clinical examination, blood pressure and anthropometric measurements were collected by trained and certified observers using standard protocols and techniques (28). Three blood pressure measurements were obtained with the participant in a seated position after 5 minutes of rest. Participants were advised to avoid cigarette smoking, alcohol, caffeinated beverages, and exercise for at least 30 minutes before their blood pressure measurement. Body weight and height were measured twice during the examination. Weight was measured in light indoor clothing without shoes to the nearest tenth of a kilogram. Height was measured without shoes to the nearest tenth of a centimeter with a stadiometer. Body mass index (weight (kg)/height (m)2) was also calculated.

Overnight fasting blood specimens were collected for measurement of serum lipids and plasma glucose. The fasting time was verified before collecting the blood specimen. Participants who had not fasted for at least 10 hours did not have their blood drawn. Blood specimens were processed at the examination center and shipped to a central clinical laboratory in Beijing, China, where the specimens were stored at –70°C until laboratory assays could be conducted. Plasma glucose was measured by use of a modified hexokinase enzymatic method. Total cholesterol, high density lipoprotein cholesterol, and triglyceride levels were analyzed enzymatically by use of commercially available reagents (29). Low density lipoprotein cholesterol levels were calculated by use of the Friedewald equation for the participants who had triglyceride levels of less than 400 mg/dl: Low density lipoprotein cholesterol = total cholesterol – high density lipoprotein cholesterol – cholesterol-triglycerides/5 (30).

Overweight or obesity was defined as a body mass index of 25.0 kg/m2 or higher; hypertension was defined as systolic blood pressure of 140 mmHg or higher, and/or diastolic blood pressure of 90 mmHg or higher, and/or use of antihypertensive medications; hypercholesterolemia was defined as serum total cholesterol of 240 mg/dl or higher, and/or low density lipoprotein cholesterol of 160 mg/dl or higher, and/or use of cholesterol-lowering medication; and diabetes was defined as fasting plasma glucose of 126 mg/dl or higher and/or use of antidiabetes medication.

All study personnel successfully completed a training program that oriented them to both the aims of the study and the specific tools and methodologies used. The study laboratory was standardized for lipid measurements according to the criteria of the Centers for Disease Control and Prevention–National Heart, Lung, and Blood Institute lipid standardization programs (31).

Statistical analysis
Age-adjusted demographic, lifestyle, and cardiovascular risk factors were determined by erectile dysfunction status, and statistical significance was tested by analysis of covariance. The age-adjusted prevalences of cardiovascular disease risk factors and cigarette smoking were compared with erectile dysfunction status, and statistical significance was tested with maximum likelihood methods. Logistic regression analysis was used to calculate the age-adjusted and the multivariate-adjusted odds ratios of erectile dysfunction associated with cigarette smoking and other cardiovascular disease risk factors. Because the odds ratios of erectile dysfunction associated with former and current smoking were the same, and because only a small proportion of study participants reported former smoking, the former and current smokers were combined in the analysis. Population attributable risk for modifiable risk factors was calculated by a standard method as follows: P(OR – 1)/(P(OR – 1) + 1) (32), where P is the proportion of the population with a risk factor, and "OR" is the odds ratio of erectile dysfunction in persons with the risk factor compared with persons without the risk factor from the logistic regression model. Population attributable risk estimates the proportion of cases that could be prevented if the risk factor could be eliminated from the total population.

All calculations were weighted to represent the total Chinese adult male population aged 35–74 years. The weights were calculated on the basis of the 2000 China Population Census data and the InterASIA sampling scheme and took into account several features of the survey including oversampling for specific age or geographic subgroups, nonresponse, and other demographic or geographic differences between the sample and the total population. Standard errors were calculated by a technique appropriate to the complex survey design. All data analyses were conducted using SUDAAN, version 9.0, software (Research Triangle Institute, Research Triangle Park, North Carolina).


   RESULTS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
DISCUSSION
 References
 
Overall, 40.9 percent of the subjects answered "always or almost always," 42.8 percent answered "usually," 15.1 percent answered "sometimes," and 1.1 percent answered "never" being able to maintain a satisfactory erection during sexual relations. The overall prevalence of erectile dysfunction among Chinese men aged 35–74 years was 16.3 percent.

On average, participants with erectile dysfunction were 8.4 years older than those without erectile dysfunction (table 1). Participants with erectile dysfunction were less likely to complete a high school education but more likely to smoke cigarettes and have hypertension compared with those without erectile dysfunction. Among participants with erectile dysfunction, the age-adjusted mean body mass index was lower, while systolic blood pressure was slightly higher than in those without erectile dysfunction. Mean levels of serum lipids and glucose were not statistically significantly different by erectile dysfunction status.


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  		TABLE 1. Age-adjusted demographic, lifestyle, and cardiovascular risk factors according to erectile dysfunction status among 4,763 Chinese men, InterASIA* study, 2000–2001{dagger}

 
The prevalence of erectile dysfunction among cigarette smokers aged 35–44, 45–54, 55–64, and 65–74 years was 6.4 percent, 17.8 percent, 44.0 percent, and 54.7 percent, respectively, and among never smokers the prevalence was 4.6 percent, 14.8 percent, 35.6 percent, and 45.6 percent, respectively (for the difference between smokers and never smokers: p = 0.01; for age trend: p < 0.0001) (figure 1).


Figure 1
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  		FIGURE 1. Age-specific prevalence of erectile dysfunction by smoking status among Chinese men aged 35–74 years, InterASIA study, 2000–2001. For the difference between smokers and never smokers: p = 0.01; for age trend: p < 0.0001. InterASIA, International Collaborative Study of Cardiovascular Disease in Asia.

 
Compared with never smokers, the age-adjusted odds ratios of erectile dysfunction associated with ever smokers, current cigarette smokers, and former smokers were 1.37 (95 percent confidence interval (CI): 1.08, 1.75), 1.37 (95 percent CI: 1.07, 1.77), and 1.38 (95 percent CI: 0.96, 2.00), respectively. After additional adjustment for education, alcohol consumption, physical inactivity, diabetes, hypertension, overweight, and dyslipidemia, the odds ratio of erectile dysfunction associated with ever smoking was 1.41 (95 percent CI: 1.09, 1.81) (table 2). In addition, less than a high school education and hypertension were significantly associated with erectile dysfunction. Alcohol consumption, diabetes, overweight, and hypercholesterolemia were not statistically significantly associated with erectile dysfunction.


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  		TABLE 2. Multivariate-adjusted odds ratios and 95% confidence intervals of erectile dysfunction associated with cigarette smoking and other cardiovascular risk factors among Chinese men, InterASIA* study, 2000–2001

 
Cigarette smoking was estimated to be attributed to 22.7 percent of erectile dysfunction cases (11.8 million) in Chinese men. In addition, less than a high school education and hypertension were estimated to be attributed to 36.5 percent (19.1 million) and 6.6 percent (3.5 million) of erectile dysfunction cases, respectively.

There was a statistically significant dose-response relation between cigarette smoking and risk of erectile dysfunction. Age-adjusted odds ratios of erectile dysfunction were 1.22 (95 percent CI: 0.88, 1.68), 1.39 (95 percent CI: 1.05, 1.85), and 1.70 (95 percent CI: 1.13, 2.56) for those who smoked 1–10, 11–20, and more than 20 cigarettes per day compared with never smokers (ptrend = 0.004), respectively. After additional adjustment for cardiovascular disease risk factors, the corresponding odds ratios were 1.27 (95 percent CI: 0.91, 1.77), 1.45 (95 percent CI: 1.08, 1.95), and 1.65 (95 percent CI: 1.08, 2.50), respectively (ptrend = 0.005) (figure 2). There was no clear trend in the duration of cigarette smoking and risk of erectile dysfunction, although any cigarette smoking was associated with increased risk. For example, age-adjusted odds ratios were 1.69 (95 percent CI: 1.02, 2.81), 1.53 (95 percent CI: 1.03, 2.27), and 1.37 (95 percent CI: 1.04, 1.81) for participants who smoked 1–10 years, 11–20 years, and more than 20 years compared with never smokers, respectively.


Figure 2
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  		FIGURE 2. Multivariate-adjusted odds ratios of erectile dysfunction associated with cigarette smoking, InterASIA study, 2000–2001. Age, education, alcohol drinking, physical activity, body mass index, hypertension, serum cholesterol, and diabetes were adjusted. InterASIA, International Collaborative Study of Cardiovascular Disease in Asia. Numbers in parentheses, 95% confidence interval.

 
Multivariate-adjusted odds ratios of erectile dysfunction associated with cigarette smoking by subgroups are presented in table 3. In general, the association between cigarette smoking and erectile dysfunction was slightly stronger among subgroups who had lower levels of cardiovascular disease risk factors. However, the association between cigarette smoking and erectile dysfunction was stronger among individuals with diabetes (odds ratio = 3.29, 95 percent CI: 1.49, 7.27).


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  		TABLE 3. Multivariate-adjusted odds ratios and 95% confidence intervals of erectile dysfunction associated with cigarette smoking by age and other cardiovascular risk factor groups among Chinese men, InterASIA* study, 2000–2001

 

   DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
References
 
Erectile dysfunction has become an important public health concern (10, 29). Although not a life-threatening condition, it compromises well-being and quality of life in men and their partners. The prevalence of erectile dysfunction varies from 16.1 percent or higher in the general population (10, 33) to almost 90.0 percent among patients with diabetes and end-stage renal disease (15, 34). Atherosclerotic vascular disease and its risk factors, such as hypertension, dyslipidemia, and diabetes, as well as depression, have been reported as major risk factors for erectile dysfunction (18, 19). Our study indicated that cigarette smoking is an independent risk factor for erectile dysfunction in Chinese men. This association was presented in a dose-response fashion and was stronger among subgroups who had lower levels of cardiovascular disease risk factors.

There are several important strengths of our study that are worth mentioning. Our study participants were from a nationally representative sample of the general Chinese population aged 35–74 years. Cigarette smoking prevalence was very high in this population. The response rate was high, especially compared with previously reported studies (33); many population-based studies on erectile dysfunction had response rates of less than 50 percent, which might bias the study findings. In addition, our study participants were at low risk for atherosclerosis, a main underlying cause for erectile dysfunction. For example, the mean level of serum total cholesterol was only 184.2 mg/dl among our study participants. Furthermore, patients with a history of myocardial infarction, stroke, and peripheral arterial disease were excluded from the current analysis in an effort to eliminate the confounding effect of atherosclerotic disease on the relation between cigarette smoking and erectile dysfunction. Finally, major cardiovascular disease risk factors, including hypertension, hypercholesterolemia, diabetes, overweight, physical activity, and education, were measured and used for multivariate adjustment. Although we have adjusted for the major risk factors of erectile dysfunction, we cannot entirely eliminate the residual confounding effect due to measurement errors or unknown (and unmeasured) risk factors in an observational study, such as ours.

Similar to previously published reports (7–16), the present investigation used a cross-sectional study design. The temporal relation between cigarette smoking and erectile dysfunction cannot be established. However, it might not be ethical to conduct randomized controlled trials to test the effect of cigarette smoking on erectile dysfunction. Therefore, a well-designed prospective cohort study with a large population-based sample would provide the best evidence for this association.

Our study did not find a significant association of diabetes, overweight, and dyslipidemia with erectile dysfunction. This discrepancy with previous reports (35) might be due to the low risk of atherosclerotic vascular disease in this Chinese population. Our study found that low educational level was associated with increased risk of erectile dysfunction. Education level is an important indicator of socioeconomic status and other behavioral risk factors. Furthermore, our study indicated that cigarette smoking and diabetes might have an additive effect on the risk of erectile dysfunction.

These study results indicate that an estimated 22.7 percent of erectile dysfunction cases among Chinese men are attributable to cigarette smoking if the association is causal. This represents more than 11.8 million preventable erectile dysfunction cases in the Chinese general population. Our study indicates that cigarette smoking is a leading modifiable risk factor for erectile dysfunction in the Chinese population.

Our study found that the risk of erectile dysfunction was the same for current and former cigarette smokers. Furthermore, our study indicated that risk of erectile dysfunction increased after 1 or more years of cigarette smoking and that there was no dose-response relation between duration of cigarette smoking and risk of erectile dysfunction. Our findings are consistent with those of other studies (7, 10, 11, 20–22) that reported that both current and former cigarette smoking increases the risk of erectile dysfunction. For example, Austoni et al. (7) reported that men who currently smoked more than 10 cigarettes/day and former smokers had significantly higher odds ratios of 1.4 and 1.3, respectively, of erectile dysfunction in comparison with never smokers in Italy.

Clinical and basic science research provides strong evidence that erectile dysfunction shares a similar pathogenesis with other forms of vascular disease (18, 19, 35). Cigarette smoking may affect penile erection by the impairment of endothelium-dependent smooth muscle relaxation (19). In addition, nicotine may inhibit smooth muscle function or the neurovascular mediators, such as prostacyclin, causing many types of hemodynamic alterations. Hypercoagulability and increased platelet aggregation, the release of fatty acids and catecholamines, and a direct toxic effect of nicotine on the vascular endothelium have also been considered as possible mechanisms (19).

In summary, our study documented an independent and dose-response relation between cigarette smoking and risk of erectile dysfunction. These results suggest that smoking prevention should be an important approach for reducing risk of erectile dysfunction.


   ACKNOWLEDGMENTS
 
The InterASIA study was funded by a contractual agreement between Tulane University, New Orleans, Louisiana, and Pfizer, Inc., New York, New York.

Conflict of interest: none declared.


   References
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 References
 

  1. Ezzati M, Lopez AD. Estimates of global mortality attributable to smoking in 2000. Lancet (2003) 362:847–52.[CrossRef][Web of Science][Medline]
  2. Porter S, Jackson K, Trosclair A, et al. Prevalence of current cigarette smoking among adults and changes in prevalence of current and some day smoking—United States, 1996 –2001. JAMA (2003) 289:2355–6.[Free Full Text]
  3. Gu D, Wu X, Reynolds K, et al. Cigarette smoking and exposure to environmental tobacco smoke in China. Am J Public Health (2004) 94:1972–6.[Abstract/Free Full Text]
  4. Reddy KS, Perry CL, Stigler MH, et al. Differences in tobacco use among young people in urban India by sex, socioeconomic status, age, and school grade: assessment of baseline survey data. Lancet (2006) 367:589–94.[CrossRef][Web of Science][Medline]
  5. Warren CW, Jones NR, Eriksen MP, et al. Patterns of global tobacco use in young people and implications for future chronic disease burden in adults. Lancet (2006) 367:749–53.[CrossRef][Web of Science][Medline]
  6. Wechsler H, Rigotti NA, Gledhill-Hoyt J, et al. Increased levels of cigarette use among college students: a cause for national concern. JAMA (1998) 280:1673–8.[Abstract/Free Full Text]
  7. Austoni E, Mirone V, Parazzini F, et al. Smoking as a risk factor for erectile dysfunction: data from the Andrology Prevention Weeks 2001 –2002. In: A study of the Italian Society of Andrology (S.I.A.). Eur Urol (2005) 48:810–18.
  8. Oksuz E, Malhan S. The prevalence of male sexual dysfunction and potential risk factors in Turkish men: a Web-based survey. Int J Impot Res (2005) 17:539–45.[CrossRef][Web of Science][Medline]
  9. Nicolosi A, Glasser DB, Moreira ED, et al. Prevalence of erectile dysfunction and associated factors among men without concomitant diseases: a population study. Int J Impot Res (2003) 15:253–7.[CrossRef][Web of Science][Medline]
  10. Mirone V, Imbimbo C, Bortolotti A, et al. Cigarette smoking as risk factor for erectile dysfunction: results from an Italian epidemiological study. Eur Urol (2002) 41:294–7.[CrossRef][Web of Science][Medline]
  11. Bortolotti A, Fedele D, Chatenoud L, et al. Cigarette smoking: a risk factor for erectile dysfunction in diabetics. Eur Urol (2001) 40:392–6.[CrossRef][Web of Science][Medline]
  12. Mannino DM, Klevens RM, Flanders WD. Cigarette smoking: an independent risk factor for impotence? Am J Epidemiol (1994) 140:1003–8.[Abstract/Free Full Text]
  13. Millett C, Wen LM, Rissel C, et al. Smoking and erectile dysfunction: findings from a representative sample of Australian men. Tob Control (2006) 15:136–9.[Abstract/Free Full Text]
  14. Saigal CS, Wessells H, Pace J, et al, Urologic Diseases in America Project. Predictors and prevalence of erectile dysfunction in a racially diverse population. In: Arch Intern Med (2006) 166:207–12.[Abstract/Free Full Text]
  15. Sasaki H, Yamasaki H, Ogawa K, et al. Prevalence and risk factors for erectile dysfunction in Japanese diabetics. Diabetes Res Clin Pract (2005) 70:81–9.[CrossRef][Web of Science][Medline]
  16. Shiri R, Hakama M, Hakkinen J, et al. Relationship between smoking and erectile dysfunction. Int J Impot Res (2005) 17:164–9.[CrossRef][Web of Science][Medline]
  17. Klein R, Klein BE, Moss SE. Ten-year incidence of self-reported erectile dysfunction in people with long-term type 1 diabetes. J Diabetes Complications (2005) 19:35–41.[CrossRef][Web of Science][Medline]
  18. Ganz P. Erectile dysfunction: pathophysiologic mechanisms pointing to underlying cardiovascular disease. Am J Cardiol (2005) 96:8M–12M.[Web of Science][Medline]
  19. Salonia A, Briganti A, Deho F, et al. Pathophysiology of erectile dysfunction. Int J Androl (2003) 26:129–36.[CrossRef][Web of Science][Medline]
  20. Polsky JY, Aronson KJ, Heaton JP, et al. Smoking and other lifestyle factors in relation to erectile dysfunction. BJU Int (2005) 96:1355–9.[CrossRef][Web of Science][Medline]
  21. Lyngdorf P, Hemmingsen L. Epidemiology of erectile dysfunction and its risk factors: a practice-based study in Denmark. Int J Impot Res (2004) 16:105–11.[CrossRef][Web of Science][Medline]
  22. Natali A, Mondaini N, Lombardi G, et al. Heavy smoking is an important risk factor for erectile dysfunction in young men. Int J Impot Res (2005) 17:227–30.[CrossRef][Web of Science][Medline]
  23. NIH Consensus Conference. Impotence: NIH Consensus Development Panel on Impotence. JAMA (1993) 270:83–90.[Abstract/Free Full Text]
  24. Feldman HA, Goldstein I, Hatzichristou DG, et al. Construction of a surrogate variable for impotence in the Massachusetts Male Aging Study. J Clin Epidemiol (1994) 47:457–67.[CrossRef][Web of Science][Medline]
  25. Shaeer KZ, Osegbe DN, Siddiqui SH, et al. Prevalence of erectile dysfunction and its correlates among men attending primary care clinics in three countries: Pakistan, Egypt, and Nigeria. Int J Impot Res (2003) 15(suppl 1):S8–14.[CrossRef][Web of Science][Medline]
  26. Nicolosi A, Moreira ED Jr, Shirai M, et al. Epidemiology of erectile dysfunction in four countries: cross-national study of the prevalence and correlates of erectile dysfunction. Urology (2003) 61:201–6.[CrossRef][Web of Science][Medline]
  27. Plan and operation of the Third National Health and Nutrition Examination Survey,1988–94. Series 1: programs and collection procedures. Vital Health Stat 1 (1994) 32:1–407.
  28. Perloff D, Grim C, Flack J, et al. Human blood pressure determination by sphygmomanometry. Circulation (1993) 88:2460–70.[Free Full Text]
  29. Allain CC, Poon LS, Chan CS, et al. Enzymatic determination of total serum cholesterol. Clin Chem (1974) 20:470–5.[Abstract]
  30. Friedewald WT, Levy RI, Fredrickson DS. Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Clin Chem (1972) 18:499–502.[Abstract]
  31. Myers GL, Cooper GR, Winn CL, et al, The Centers for Disease Control–National Heart, Lung and Blood Institute Lipid Standardization Program. An approach to accurate and precise lipid measurements. In: Clin Lab Med (1989) 9:105–35.[Web of Science][Medline]
  32. Leviton A. Definition of attributable risk. (Letter). Am J Epidemiol (1973) 98:231.[Free Full Text]
  33. Nicolosi A, Laumann EO, Glasser DB, et al. Sexual behavior and sexual dysfunctions after age 40: the global study of sexual attitudes and behaviors. Urology (2004) 64:991–7.[CrossRef][Web of Science][Medline]
  34. Krishnan R, Izatt S, Bargman JM, et al. Prevalence and determinants of erectile dysfunction in patients on peritoneal dialysis. Int Urol Nephrol (2003) 35:553–6.[CrossRef][Medline]
  35. Sullivan ME, Keoghane SR, Miller MA. Vascular risk factors and erectile dysfunction. BJU Int (2001) 87:838–45.[CrossRef][Web of Science][Medline]

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