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Dive into the research topics where Frederick C. W. Wu is active.

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Featured researches published by Frederick C. W. Wu.


European Urology | 2009

Investigation, Treatment, and Monitoring of Late-Onset Hypogonadism in Males: ISA, ISSAM, EAU, EAA, and ASA Recommendations

Christina Wang; Eberhard Nieschlag; Ronald S. Swerdloff; Hermann M. Behre; Wayne J.G. Hellstrom; Louis Gooren; Jean-Marc Kaufman; Jean-Jacques Legros; Bruno Lunenfeld; Alvaro Morales; John E. Morley; Claude Schulman; Ian M. Thompson; W. Weidner; Frederick C. W. Wu

The new ISA, ISSAM, EAU, EAA and ASA recommendations on the investigation, treatment and monitoring of late-onset hypogonadism in males provide updated evidence-based information for clinicians who diagnose and treat patients with adult onset, age related testosterone deficiency.


The Journal of Clinical Endocrinology and Metabolism | 2008

Hypothalamic-pituitary-testicular axis disruptions in older men are differentially linked to age and modifiable risk factors: The European Male Aging Study

Frederick C. W. Wu; Abdelouahid Tajar; Stephen R. Pye; A J Silman; Joseph D. Finn; Terence W. O'Neill; Gyorgy Bartfai; Felipe F. Casanueva; Gianni Forti; Aleksander Giwercman; Ilpo Huhtaniemi; Krzysztof Kula; Margus Punab; Steven Boonen; Dirk Vanderschueren

CONTEXT The cause of declining testosterone (T) in aging men and their relationships with risk factors are unclear. OBJECTIVE The objective of the study was to investigate the relationships between lifestyle and health with reproductive hormones in aging men. DESIGN This was a baseline cross-sectional survey on 3200 community-dwelling men aged 40-79 yr from a prospective cohort study in eight European countries. RESULTS Four predictors were associated with distinct modes of altered function: 1) age: lower free T (FT; -3.12 pmol/liter.yr, P < 0.001) with raised LH, suggesting impaired testicular function; 2) obesity: lower total T (TT; -2.32 nmol/liter) and FT (-17.60 pmol/liter) for body mass index (BMI; > or = 25 to < 30 kg/m(2)) and lower TT (-5.09 nmol/liter) and FT (-53.72 pmol/liter) for BMI 30 kg/m(2) or greater (P < 0.001-0.01, referent: BMI < 25 kg/m(2)) with unchanged/decreased LH, indicating hypothalamus/pituitary dysfunction; 3) comorbidity: lower TT (-0.80 nmol/liter, P < 0.01) with unchanged LH in younger men but higher LH in older men; and 4) smoking: higher SHBG (5.96 nmol/liter, P < 0.001) and LH (0.77 U/liter, P < 0.01) with increased TT (1.31 nmol/liter, P < 0.001) but not FT, compatible with a resetting of T-LH-negative feedback due to elevated SHBG. CONCLUSIONS Complex multiple alterations in the hypothalamic-pituitary-testicular axis function exist in aging men against a background of progressive age-related testicular impairment. These changes are differentially linked to specific risk factors. Some risk factors operate independently of but others interact with age, in contributing to the T decline. These potentially modifiable risk factors suggest possible preventative measures to maintain T during aging in men.


The Journal of Clinical Endocrinology and Metabolism | 2010

Effects of Testosterone on Muscle Strength, Physical Function, Body Composition, and Quality of Life in Intermediate-Frail and Frail Elderly Men: A Randomized, Double-Blind, Placebo-Controlled Study

Upendram Srinivas-Shankar; Stephen A Roberts; Martin J. Connolly; Matthew D. L. O'Connell; Judith E. Adams; Jackie Oldham; Frederick C. W. Wu

CONTEXT Physical frailty is associated with reduced muscle strength, impaired physical function, and quality of life. Testosterone (T) increases muscle mass and strength in hypogonadal patients. It is unclear whether T has similar effects in intermediate-frail and frail elderly men with low to borderline-low T. OBJECTIVE Our objective was to determine the effects of 6 months T treatment in intermediate-frail and frail elderly men, on muscle mass and strength, physical function, and quality of life. DESIGN AND SETTING We conducted a randomized, double-blind, placebo-controlled, parallel-group, single-center study. PARTICIPANTS PARTICIPANTS were community-dwelling intermediate-frail and frail elderly men at least 65 yr of age with a total T at or below 12 nmol/liter or free T at or below 250 pmol/liter. METHODS Two hundred seventy-four participants were randomized to transdermal T (50 mg/d) or placebo gel for 6 months. Outcome measures included muscle strength, lean and fat mass, physical function, and self-reported quality of life. RESULTS Isometric knee extension peak torque improved in the T group (vs. placebo at 6 months), adjusted difference was 8.6 (95% confidence interval, 1.3-16.0; P = 0.02) Newton-meters. Lean body mass increased and fat mass decreased significantly in the T group by 1.08 +/- 1.8 and 0.9 +/- 1.6 kg, respectively. Physical function improved among older and frailer men. Somatic and sexual symptom scores decreased with T treatment; adjusted difference was -1.2 (-2.4 to -0.04) and -1.3 (-2.5 to -0.2), respectively. CONCLUSIONS T treatment in intermediate-frail and frail elderly men with low to borderline-low T for 6 months may prevent age-associated loss of lower limb muscle strength and improve body composition, quality of life, and physical function. Further investigations are warranted to extend these results.


European Journal of Endocrinology | 2008

Investigation, treatment and monitoring of late-onset hypogonadism in males: ISA, ISSAM, EAU, EAA and ASA recommendations

Cong-Yi Wang; Eberhard Nieschlag; Ronald S. Swerdloff; Hermann M. Behre; Wayne J.G. Hellstrom; Louis Gooren; Jean-Marc Kaufman; Jean-Jacques Legros; Bruno Lunenfeld; Alvaro Morales; John E. Morley; Claude Schulman; Ian M. Thompson; W. Weidner; Frederick C. W. Wu

Demographic data clearly demonstrate that the percentage of the population in the older age group is increasing. Androgen deficiency in the aging male has become a topic of increasing interest and debate throughout the world. Cross-sectional and longitudinal data indicate that the testosterone falls progressively with age and that a significant percentage of men over the age of 60 years have serum testosterone levels that are below the lower limits of young adult (age 20–30 years) men (1–4). The principal questions raised by these observations are whether older hypogonadal men will benefit from testosterone treatment and what will be the risks associated with such intervention. The past decade has brought evidence of benefit of androgen treatment of hypogonadal men on multiple target organs and the recent studies show short-term beneficial effects of testosterone in older men that are similar to those in younger men. This has been comprehensively reviewed and summarized by the Institute of Medicine in ‘Testosterone and Aging: Clinical Research Directions’ (5). Long-term data on the effects of testosterone treatment in the older population are limited mainly to effects on body composition and bone mass (6–11). Key questions of the effects of testosterone on patient reported outcomes and functional benefits that may retard physical or mental frailty of the elderly or improve the quality of life are not yet available. Specific risk data on the prostate and cardiovascular systems are needed.


Archives of Sexual Behavior | 1983

Changes in erectile responsiveness during androgen replacement therapy

John Bancroft; Frederick C. W. Wu

Erections in response to erotic films and fantasies were measured in eight hypogonadal men, with and without androgen replacement, and eight age-matched controls. Erections to films in the hypogonadal men did not differ from those of the controls and were not affected by androgen replacement. Erections to fantasy were significantly smaller and slower to develop in the hypogonadal men and did show significant improvement during androgen replacement. These preliminary results suggest that erections to certain types of stimuli are relatively independent of androgens, whereas the response to fantasy may be androgen dependent. The implications of these findings are discussed.


The Journal of Clinical Endocrinology and Metabolism | 2010

Characteristics of Secondary, Primary, and Compensated Hypogonadism in Aging Men: Evidence from the European Male Ageing Study

Abdelouahid Tajar; Gianni Forti; Terence W. O'Neill; David M. Lee; A J Silman; Joseph D. Finn; G. Bartfai; Steven Boonen; Felipe F. Casanueva; Aleksander Giwercman; Thang S. Han; Krzysztof Kula; Fernand Labrie; Michael E. J. Lean; Neil Pendleton; Margus Punab; Dirk Vanderschueren; Ilpo Huhtaniemi; Frederick C. W. Wu

CONTEXT The diagnosis of late-onset hypogonadism (LOH) in older men with age-related declines in testosterone (T) is currently not well characterized. OBJECTIVE Our objective was to investigate whether different forms of hypogonadism can be distinguished among aging men. DESIGN The study was a cross-sectional survey on 3369 community-dwelling men aged 40-79 yr in eight European centers. METHODS Four groups of subjects were defined: eugonadal (normal T and normal LH), secondary (low T and low/normal LH), primary (low T and elevated LH), and compensated (normal T and elevated LH) hypogonadism. Relationships between the defined gonadal status with potential risk factors and clinical symptoms were investigated by multilevel regression models. RESULTS Among the men, 11.8, 2.0, and 9.5% were classified into the secondary, primary, and compensated hypogonadism categories, respectively. Older men were more likely to have primary [relative risk ratio (RRR) = 3.04; P < 0.001] and compensated (RRR = 2.41; P < 0.001) hypogonadism. Body mass index of 30 kg/m(2) or higher was associated with secondary hypogonadism (RRR = 8.74; P < 0.001). Comorbidity was associated with both secondary and primary hypogonadism. Sexual symptoms were more prevalent in secondary and primary hypogonadism, whereas physical symptoms were more likely in compensated hypogonadism. CONCLUSIONS Symptomatic elderly men considered to have LOH can be differentiated on the basis of endocrine and clinical features and predisposing risk factors. Secondary hypogonadism is associated with obesity and primary hypogonadism predominately with age. Compensated hypogonadism can be considered a distinct clinical state associated with aging. Classification of LOH into different categories by combining LH with T may improve the diagnosis and management of LOH.


The Journal of Sexual Medicine | 2010

Age‐Related Changes in General and Sexual Health in Middle‐Aged and Older Men: Results from the European Male Ageing Study (EMAS)

Giovanni Corona; David M. Lee; Gianni Forti; Daryl B. O'Connor; Mario Maggi; Terence W. O'Neill; Neil Pendleton; Gyorgy Bartfai; Steven Boonen; Felipe F. Casanueva; Joseph D. Finn; Aleksander Giwercman; Thang S. Han; Ilpo Huhtaniemi; Krzysztof Kula; Michael E. J. Lean; Margus Punab; A J Silman; Dirk Vanderschueren; Frederick C. W. Wu

INTRODUCTION Limited information is available concerning the general and sexual health status of European men. AIM To investigate the age-related changes in general and sexual health in middle-aged and older men from different countries of the European Union. METHODS This is a cross-sectional multicenter survey performed on a sample of 3,369 community-dwelling men aged 40-79 years old (mean 60 + or - 11 years). Subjects were randomly selected from eight European centers including centers from nontransitional (Florence [Italy], Leuven [Belgium], Malmö[Sweden], Manchester [United Kingdom], Santiago de Compostela [Spain]) and transitional countries (Lodz [Poland], Szeged [Hungary], Tartu [Estonia]). MAIN OUTCOME MEASURES Different parameters were evaluated including the Becks Depression Inventory for the quantification of depressive symptoms, the Short Form-36 Health Survey for the assessment of the quality of life (QoL), the International Prostate Symptom Score for the evaluation of lower urinary tract symptoms, and the European Male Ageing Study sexual function questionnaire for the study of sexual function. RESULTS More than 50% of subjects reported the presence of one or more common morbidities. Overall, hypertension (29%), obesity (24%), and heart diseases (16%) were the most prevalent conditions. Around 30% of men reported erectile dysfunction (ED) and 6% reported severe orgasmic impairment, both of which were closely associated with age and concomitant morbidities. Only 38% of men reporting ED were concerned about it. Furthermore, concern about ED increased with age, peaking in the 50-59 years age band, but decreased thereafter. Men in transitional countries reported a higher prevalence of morbidities and impairment of sexual function as well as a lower QoL. CONCLUSION Sexual health declined while concomitant morbidities increased in European men as a function of age. The burden of general and sexual health is higher in transitional countries, emphasizing the need to develop more effective strategies to promote healthy aging for men in these countries.


Mayo Clinic Proceedings. 2012;87(8):766-778. | 2012

The Princeton III Consensus Recommendations for the Management of Erectile Dysfunction and Cardiovascular Disease

Ajay Nehra; Graham Jackson; Martin Miner; Kevin L. Billups; Arthur L. Burnett; Jacques Buvat; Culley C. Carson; Glenn R. Cunningham; Peter Ganz; Irwin Goldstein; André T. Guay; Geoff Hackett; Robert A. Kloner; John B. Kostis; Piero Montorsi; Melinda Ramsey; Raymond C. Rosen; Richard Sadovsky; Allen D. Seftel; Ridwan Shabsigh; Charalambos Vlachopoulos; Frederick C. W. Wu

The Princeton Consensus (Expert Panel) Conference is a multispecialty collaborative tradition dedicated to optimizing sexual function and preserving cardiovascular health. The third Princeton Consensus met November 8 to 10, 2010, and had 2 primary objectives. The first objective focused on the evaluation and management of cardiovascular risk in men with erectile dysfunction (ED) and no known cardiovascular disease (CVD), with particular emphasis on identification of men with ED who may require additional cardiologic work-up. The second objective focused on reevaluation and modification of previous recommendations for evaluation of cardiac risk associated with sexual activity in men with known CVD. The Panels recommendations build on those developed during the first and second Princeton Consensus Conferences, first emphasizing the use of exercise ability and stress testing to ensure that each mans cardiovascular health is consistent with the physical demands of sexual activity before prescribing treatment for ED, and second highlighting the link between ED and CVD, which may be asymptomatic and may benefit from cardiovascular risk reduction.


The Journal of Clinical Endocrinology and Metabolism | 2011

Reference Ranges for Testosterone in Men Generated Using Liquid Chromatography Tandem Mass Spectrometry in a Community-Based Sample of Healthy Nonobese Young Men in the Framingham Heart Study and Applied to Three Geographically Distinct Cohorts

Shalender Bhasin; Michael J. Pencina; Guneet K. Jasuja; Thomas G. Travison; Andrea D. Coviello; Eric S. Orwoll; Patty Y. Wang; Carrie M. Nielson; Frederick C. W. Wu; Abdelouahid Tajar; Fernand Labrie; Hubert W. Vesper; Anqi Zhang; Jagadish Ulloor; Ravinder J. Singh; Ralph B. D'Agostino

CONTEXT Reference ranges are essential for partitioning testosterone levels into low or normal and making the diagnosis of androgen deficiency. We established reference ranges for total testosterone (TT) and free testosterone (FT) in a community-based sample of men. METHODS TT was measured using liquid chromatography tandem mass spectrometry in nonobese healthy men, 19-40 yr old, in the Framingham Heart Study Generation 3; FT was calculated. Values below the 2.5th percentile of reference sample were deemed low. We determined the association of low TT and FT with physical dysfunction, sexual symptoms [European Male Aging Study (EMAS) only], and diabetes mellitus in three cohorts: Framingham Heart Study generations 2 and 3, EMAS, and the Osteoporotic Fractures in Men Study. RESULTS In a reference sample of 456 men, mean (sd), median (quartile), and 2.5th percentile values were 723.8 (221.1), 698.7 (296.5), and 348.3 ng/dl for TT and 141. 8 (45.0), 134.0 (60.0), and 70.0 pg/ml for FT, respectively. In all three samples, men with low TT and FT were more likely to have slow walking speed, difficulty climbing stairs, or frailty and diabetes than those with normal levels. In EMAS, men with low TT and FT were more likely to report sexual symptoms than men with normal levels. Men with low TT and FT were more likely to have at least one of the following: sexual symptoms (EMAS only), physical dysfunction, or diabetes. CONCLUSION Reference ranges generated in a community-based sample of men provide a rational basis for categorizing testosterone levels as low or normal. Men with low TT or FT by these criteria had higher prevalence of physical dysfunction, sexual dysfunction, and diabetes. These reference limits should be validated prospectively in relation to incident outcomes and in randomized trials.


The Journal of Clinical Endocrinology and Metabolism | 2012

Characteristics of Androgen Deficiency in Late-Onset Hypogonadism: Results from the European Male Aging Study (EMAS).

Abdelouahid Tajar; Ilpo Huhtaniemi; Terence W. O'Neill; Joseph D. Finn; Stephen R. Pye; David M. Lee; Gyorgy Bartfai; Steven Boonen; Felipe F. Casanueva; Gianni Forti; Aleksander Giwercman; Thang S. Han; Krzysztof Kula; Fernand Labrie; Michael E. J. Lean; Neil Pendleton; Margus Punab; Dirk Vanderschueren; Frederick C. W. Wu

CONTEXT Late-onset hypogonadism (LOH) has been defined as a syndrome in middle-aged and elderly men reporting symptoms in the presence of low testosterone (T). OBJECTIVE The objective of the study was to seek objective biochemical and end-organ evidence of androgen deficiency in men classified as having LOH according to our previously published criteria. DESIGN, SETTING, AND PARTICIPANTS The design of the study included cross-sectional data from the European Male Aging Study on 2966 community-dwelling men aged 40-79 years in eight European countries. MAIN OUTCOME MEASURE(S) Waist circumference, body mass index, muscle mass, estimated heel bone mineral density (eBMD), hemoglobin, insulin sensitivity, physical activity, metabolic syndrome, insulin resistance index, and cardiovascular disease were measured. RESULTS Sixty-three men (2.1%) were classified as having LOH: 36 moderate and 27 severe. They were older and more obese than eugonadal men and had, in proportion to the graded T deficiency, lower muscle mass, eBMD, and hemoglobin, with poorer general health. Both moderate and severe LOH was associated with lower hemoglobin, mid-upper arm circumference, eBMD, physical function (measured by the Short Form-36 questionnaire), slower gait speed and poorer general health. Only men with severe LOH showed significant associations with larger waist circumference (β=1.93 cm; 0.04-3.81), insulin resistance (β=2.81; 1.39-4.23), and the metabolic syndrome (odds ratio 9.94; 2.73-36.22) after adjustments for confounders. Men with low testosterone only (irrespective of symptoms) showed lesser magnitudes of association with the same end points. CONCLUSIONS LOH is associated with multiple end-organ deficits compatible with androgen deficiency. These data support the existence of a syndrome of LOH in only a minority of aging men, especially those with T below 8 nmol/liter.

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Dirk Vanderschueren

Katholieke Universiteit Leuven

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Joseph D. Finn

University of Manchester

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Krzysztof Kula

Medical University of Łódź

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Terence W. O'Neill

Manchester Academic Health Science Centre

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Neil Pendleton

University of Manchester

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