title: Prevalence and incidence of androgen deficiency in middle-aged and older men: estimates from the Massachusetts Male Aging Study. Endogenous Testosterone and Mortality Due to All Causes, Cardiovascular Disease, and Cancer in Men: European Prospective Investigation Into Cancer in Norfolk (EPIC-Norfolk) Prospective Population Study Prevalence of symptomatic androgen deficiency in men. Endogenous testosterone levels, physical performance, and fall risk in older men. IS ROUTINE HORMONAL MEASUREMENT NECESSARY IN INITIAL EVALUATION OF MEN WITH ERECTILE DYSFUNCTION? Identification of late-onset hypogonadism in middle-aged and elderly men. Relationship between the Saint Louis University ADAM questionnaire and sexual hormonal levels in a male outpatient population over 50 years of age. Relationship between testosterone serum levels and lifestyle in aging men Age trends in the level of serum testosterone and other hormones in middle-aged men: longitudinal results from the Massachusetts male aging study. Differences between univariate and bivariate models for summarizing diagnostic accuracy may not be large. Hypothalamic-pituitary-testicular axis disruptions in older men are differentially linked to age and modifiable risk factors: the European Male Aging Study. Serum testosterone levels in diabetic men with and without erectile dysfunction Long-term testosterone gel (AndroGel) treatment maintains beneficial effects on sexual function and mood, lean and fat mass, and bone mineral density in hypogonadal men. Correlates of low testosterone and symptomatic androgen deficiency in a population-based sample. Users' guides to the medical literature. III. How to use an article about a diagnostic test. B. What are the results and will they help me in caring for my patients? The Evidence-Based Medicine Working Group.
abstract: Little is known about the descriptive epidemiology of and rogen deficiency . In this study , we sought to address this issue by providing estimates of the crude and age-specific prevalence and incidence rates of and rogen deficiency in a r and omly sample d population -based cohort of middle-aged and older men . Data on and rogen deficiency ( defined using both signs/symptoms plus total and calculated free testosterone ) were available for n = 1691 ( baseline ) and n = 1087 ( follow-up ) men from the Massachusetts Male Aging Study .  Crude and age-specific prevalence and incidence rates were calculated . Based on these estimates , projections for the number of cases of and rogen deficiency in the 40- to 69-yr-old U.S. male population were computed . Estimates of the crude prevalence of and rogen deficiency at baseline and follow-up were 6.0 and 12.3 % , respectively . Prevalence increased significantly with age . From baseline age-specific prevalence data , it is estimated that there are approximately 2.4 million 40- to 69-yr-old U.S. males with and rogen deficiency . The crude incidence rate of and rogen deficiency was 12.3 per 1,000 person-years , and the rate increased significantly ( P < 0.0001 ) with age . Based on these incidence data , we can expect approximately 481,000 new cases of and rogen deficiency per year in U.S. men 40 - 69 yr old Background — The relation between endogenous testosterone concentrations and health in men is controversial . Methods and Results — We examined the prospect i ve relationship between endogenous testosterone concentrations and mortality due to all causes , cardiovascular disease , and cancer in a nested case-control study based on 11 606 men aged 40 to 79 years surveyed in 1993 to 1997 and followed up to 2003 . Among those without prevalent cancer or cardiovascular disease , 825 men who subsequently died were compared with a control group of 1489 men still alive , matched for age and date of baseline visit .  Endogenous testosterone concentrations at baseline were inversely related to mortality due to all causes ( 825 deaths ) , cardiovascular disease ( 369 deaths ) , and cancer ( 304 deaths ) . Odds ratios ( 95 % confidence intervals ) for mortality for increasing quartiles of endogenous testosterone compared with the lowest quartile were 0.75 ( 0.55 to 1.00 ) , 0.62 ( 0.45 to 0.84 ) , and 0.59 ( 0.42 to 0.85 ) , respectively ( P<0.001 for trend after adjustment for age , date of visit , body mass index , systolic blood pressure , blood cholesterol , cigarette smoking , diabetes mellitus , alcohol intake , physical activity , social class , education , dehydroepi and rosterone sulfate , and rostanediol glucuronide , and sex hormone binding globulin ) . An increase of 6 nmol/L serum testosterone ( ≈1 SD ) was associated with a 0.81 ( 95 % confidence interval 0.71 to 0.92 , P<0.01 ) multivariable-adjusted odds ratio for mortality . Inverse relationships were also observed for deaths due to cardiovascular causes and cancer and after the exclusion of deaths that occurred in the first 2 years . Conclusions — In men  , endogenous testosterone concentrations are inversely related to mortality due to cardiovascular disease and all causes . Low testosterone may be a predictive marker for those at high risk of cardiovascular disease CONTEXT Despite recognition that and rogen deficiency in men should be defined according to biochemical and clinical criteria , most prevalence estimates are based on low testosterone levels alone . OBJECTIVE The objective of this study was to examine the association between symptoms of and rogen deficiency and low total and calculated free testosterone levels and estimate the prevalence of symptomatic and rogen deficiency in men . DESIGN This study was a population -based , observational survey . PARTICIPANTS A total of 1,475 Black , Hispanic , and white men , between the ages of 30 - 79 yr , with complete data on testosterone , SHBG , and symptoms of and rogen deficiency , and who are not taking medications that impact sex steroid levels were r and omly selected from the Boston Area Community Health Survey . OUTCOME Outcomes were measured as symptomatic and rogen deficiency , defined as low total ( < 300 ng/dl ) and free ( < 5 ng/dl ) testosterone plus presence of low libido , erectile dysfunction , osteoporosis or fracture , or two or more of following symptoms : sleep disturbance , depressed mood , lethargy , or diminished physical performance . RESULTS Mean age of the sample was 47.3 + /- 12.5 yr . Approximately 24 % of subjects had total testosterone less than 300 ng/dl , and 11 % of subjects had free testosterone less than 5 ng/dl . Prevalence of symptoms were as follows : low libido ( 12 % ) , erectile dysfunction ( 16 % ) , osteoporosis/fracture ( 1 % ) , and two or more of the nonspecific symptoms ( 20 % ) . Low testosterone levels were associated with symptoms , but many men with low testosterone levels were asymptomatic ( e.g. in men 50 + yr , 47.6 % ) . Crude prevalence of symptomatic and rogen deficiency was 5.6 % ( 95 % confidence interval : 3.6 % , 8.6 % ) , and was not significantly related to race and ethnic group . Prevalence was low in men less than 70 yr ( 3.1 - 7.0 % ) and increased markedly with age to 18.4 % among 70 yr olds . Projection of these estimates to the year 2025 suggests that there will be as many as 6.5 million American men ages 30 - 79 yr with symptomatic and rogen deficiency , an increase of 38 % from 2000 population estimates . CONCLUSIONS Prevalence of symptomatic and rogen deficiency in men 30 and 79 yr of age is 5.6 % and increases substantially with age . The aging of the U.S. male population will cause a large increase in the burden of symptomatic and rogen deficiency . Future work should address the clinical significance of low testosterone levels in asymptomatic men BACKGROUND Gonadal steroid levels decline with age in men . Whether low testosterone levels affect the development of common age-related disorders , including physical functioning and falling , is unclear . METHODS This longitudinal , observational follow-up study sought to determine whether low testosterone levels are associated with physical performance and fall risk in older men . A total of 2587 community-based men aged 65 to 99 years were selected using a stratified r and om sampling scheme from a study cohort of 5995 volunteers .  Bioavailable testosterone and estradiol levels and physical performance measures were determined from baseline . Incident falls were ascertained every 4 months during 4 years of follow-up . Generalized estimating equations were used to estimate risk ratios for the relation of sex steroids to falls . RESULTS Fifty-six percent of the men reported at least 1 fall ; many fell frequently . Lower bioavailable testosterone levels were associated with increased fall risk . Men with testosterone levels in the lowest quartile had a 40 % higher fall risk than those in the highest quartile . The effect of low testosterone levels was most apparent in younger men ( 65 - 69 years ) ( relative risk , 1.8 ; 95 % confidence interval , 1.2 - 2.7 ) ; testosterone level was not associated with falls in the oldest men ( > /=80 years ) . Lower testosterone concentrations were associated with reduced physical performance . However , the association between low testosterone levels and fall risk persisted despite adjustment for performance . CONCLUSIONS Falls were common among older men . Fall risk was higher in men with lower bioavailable testosterone levels . The effect of testosterone level was independent of poorer physical performance , suggesting that the effect of testosterone on fall risk may be mediated by other and rogen actions To prospect ively compare serum hormone levels and the incidence of hormonal pathologies between men with and without erectile dysfunction , and investigate risk factors that might predict hormonal pathologies in men complaining of erectile dysfunction . The study included 262 men with erectile dysfunction and 53 healthy men with no erectile dysfunction as a control group . All men enrolled in the study were evaluated with a detailed history , physical examination ,  international index of erectile function ( IIEF-5 ) , and  serum hormone measurement .  Hypotestosteronemia was considered as serum total testosterone value of <3 ng/mL , and hyperprolactinemia was considered as serum prolactin level of > 18 ng/mL. Serum hormone levels and the incidence of hormonal abnormalities were compared between the two groups . In addition , risk factors for hormonal abnormalities were investigated . There were no significant differences in the mean serum FSH ( p = 0.212 ) , LH ( p = 0.623 ) , testosterone ( p = 0.332 ) and prolactin values ( p = 0.351 ) between the men with and without erectile dysfunction . Hypotestosteronemia was detected in 29 ( 11 % ) of the erectile dysfunction group and in 2 ( 3.7 % ) of the control group , revealing no significant difference ( p = 0.104 ) . Hyperprolactinemia was detected in 25 ( 9.5 % ) of the erectile dysfunction group and in 2 ( 3.7 % ) of the control group , revealing no significant difference ( p = 0.171 ) . To investigate risk factors that might predict hormonal pathologies , there were no significant differences in the patient age , duration of the sexual dysfunction , smoking history and duration , the presence of chronic disease and the type of erectile dysfunction . Our findings suggest that hormonal measurement should not be routinely performed in the initial evaluation of men presenting with erectile dysfunction , and may be necessary based only on the findings obtained with a careful history and physical examination BACKGROUND The association between aging-related testosterone deficiency and late-onset hypogonadism in men remains a controversial concept . We sought evidence -based criteria for identifying late-onset hypogonadism in the general population on the basis of an association between symptoms and a low testosterone level . METHODS We surveyed a r and om population sample of 3369 men between the ages of 40 and 79 years at eight European centers . Using question naires , we collected data with regard to the subjects ' general , sexual , physical , and psychological health . Levels of total testosterone  were measured in morning blood sample s by mass spectrometry , and  free testosterone levels  were calculated with the use of Vermeulen 's formula . Data were r and omly split into separate training and validation sets for confirmatory analyses . RESULTS In the training set , symptoms of poor morning erection , low sexual desire , erectile dysfunction , inability to perform vigorous activity , depression , and fatigue were significantly related to the testosterone level . Increased probabilities of the three sexual symptoms and limited physical vigor were discernible with decreased testosterone levels ( ranges , 8.0 to 13.0 nmol per liter [ 2.3 to 3.7 ng per milliliter ] for total testosterone and 160 to 280 pmol per liter [ 46 to 81 pg per milliliter ] for free testosterone ) . However , only the three sexual symptoms had a syndromic association with decreased testosterone levels . An inverse relationship between an increasing number of sexual symptoms and a decreasing testosterone level was observed . These relationships were independently confirmed in the validation set , in which the strengths of the association between symptoms and low testosterone levels determined the minimum criteria necessary to identify late-onset hypogonadism . CONCLUSIONS Late-onset hypogonadism can be defined by the presence of at least three sexual symptoms associated with a total testosterone level of less than 11 nmol per liter ( 3.2 ng per milliliter ) and a free testosterone level of less than 220 pmol per liter ( 64 pg per milliliter ) OBJECTIVES To determine the relationship between the ADAM question naire and the sexual hormonal levels in a male population older than 50 yr , and to know the predictive capacity of this question naire with regard to biochemical hypogonadism in the ageing male . METHODS A prospect i ve study was carried out on 230 Spanish men . Patients were evaluated by clinical history . The ADAM question naire and the Yesavage 's Geriatric Depression Scale were completed by each patient . Blood tests were performed including total testosterone , SHBG , free testosterone ( FT ) , dehidroepi and rosterone sulfate ( DHEA-S ) , and rostenedione , 17-beta-estradiol , FSH , LH , and prolactin . The relationship between positive ADAM question naire and age , clinical and sociodemographic background s , and hormone levels was analysed by means of uni- and multivariate tests . The capacity of the ADAM question naire to predict biochemical hypogonadism was determined with a chi-square test . RESULTS ADAM question naire ( excluding men with positive Yesavage 's Scale ) was positive in 140 patients ( 67.9 % ) . With respect to clinical background s , diabetes mellitus and age had a significant relationship with an ADAM-positive question naire . With respect to hormones , FT and DHEA-S levels were significantly lower when the ADAM question naire was positive . In the multivariate analysis , age , FT , and diabetes were independently related to an ADAM-positive question naire . Prevalence of biochemical hypogonadism ( FT<0.228 nmol/l ) was 24.6 % . The ADAM test had a sensitivity of 84.0 % and a specificity of 36.6 % to detect biochemical hypogonadism . CONCLUSIONS FT is inversely related to the ADAM-positive question naire , independently of age . The ADAM question naire is a valid test to detect hypogonadism but has low specificity Objective . The aim of this study was to evaluate the association between serum levels of testosterone and free testosterone to lifestyle in aging males . Methods . Men between 45 and 85 years were assessed regarding body mass index ( BMI ) , nicotine and alcohol consumption , stress level , physical and social activity , and sleeping quality by a self-administered question naire . In parallel , serum levels of testosterone ( T ) , free testosterone ( fT ) , LH , FSH , DHEA-S , E2 and SHBG were obtained . Results . In total , 375 men with a mean age of 59.9 years ( 9.2 ± SD ) entered this study ; 25.4 % and 27.4 % had hypogonadal testosterone or free testosterone serum levels ,  respectively . Nicotine  consumption ( smokers had higher levels of T and fT ; p < 0.01 ) , BMI ( negative correlation to T ; p < 0.01 ) and age ( negative correlation to fT ; p < 0.001 ) correlated with serum levels of testosterone or free testosterone . Physical and social activity , nicotine and alcohol consumption , stress level and sleep quality did not show a significant association with serum and rogen levels . Conclusion . This prospect i ve study of 375 men aged 45 to 85 years confirms the correlation between age , BMI and smoking with serum levels of testosterone and free testosterone , whereas the investigated variety of lifestyle factors did not show a significant association to serum and rogen levels We used longitudinal data from the Massachusetts Male Aging Study , a large population -based r and om- sample cohort of men aged 40 - 70 yr at baseline , to establish normative age trends for serum level of T and related hormones in middle-aged men and to test whether general health status affected the age trends . Of 1,709 men enrolled in 1987 - 1989 , 1,156 were followed up 7 - 10 yr afterward . By repeated- measures statistical analysis , we estimated simultaneously the cross-sectional age trend of each hormone between subjects within the baseline data , the cross-sectional trend between subjects within the follow-up data , and the longitudinal trend within subjects between baseline and follow-up . Total T declined cross-sectionally at 0.8%/yr of age within the follow-up data , whereas both free and albumin-bound T declined at about 2%/yr , all significantly more steeply than within the baseline data . Sex hormone-binding globulin increased cross-sectionally at 1.6%/yr in the follow-up data , similarly to baseline . The longitudinal decline within subjects between baseline and follow-up was considerably steeper than the cross-sectional trend within measurement times for total T ( 1.6%/yr ) and bioavailable T ( 2 - 3%/yr ) . Dehydroepi and rosterone , dehydroepi and rosterone sulfate , cortisol , and estrone showed significant longitudinal declines , whereas dihydrotestosterone , pituitary gonadotropins , and PRL rose longitudinally . Apparent good health , defined as absence of chronic illness , prescription medication , obesity , or excessive drinking , added 10 - 15 % to the level of several and rogens and attenuated the cross-sectional trends in T and LH but did not otherwise affect longitudinal or cross-sectional trends . The paradoxical finding that longitudinal age trends were steeper than cross-sectional trends suggests that incident poor health may accelerate the age-related decline in and rogen levels OBJECTIVE Experts recommend r and om effects bivariate logitnormal sensitivity and specificity estimates , rather than directly summarized univariate likelihood ratios ( LRs ) for diagnostic test meta-analyses . We assessed whether bivariate measures might cause different clinical conclusions compared with those from simpler univariate measures . STUDY DESIGN From two articles that described the benefits of bivariate r and om effects measures , we reanalyzed results and compared outcomes to univariate r and om effects summary estimates of sensitivity , specificity , and LRs . We also reanalyzed data from two published clinical examination studies to assess differences in the two methods . RESULTS The median difference between bivariate and univariate methods for sensitivity was 1.5 % ( range : 0 - 6 % ) and for specificity was 1.5 % ( range : 0 - 4 % ) . Using a pretest probability of 50 % , the median difference in posterior probability was 2.5 % ( interquartile range : 2.2 - 3.2 % , overall range : 0 - 11 % ) . For sparse data , continuity adjustment affected the differences . Adding 0.5 to each cell of studies containing at least one cell with zero patients provided the most consistent result . CONCLUSIONS Bivariate estimates of sensitivity and specificity generate summary LRs similar to those derived with univariate methods . Our empiric results suggest that recalculating LRs in published research will not likely create dramatic changes as a function of the r and om effects measure chosen 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 prospect i ve 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 re setting 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 Diabetes mellitus is a common chronic disease , affecting 0.5–2 % worldwide . The Massachusetts Male Aging Study reported that up to 75 % of men with diabetes have a lifetime risk of developing ED . Type 2 diabetes is associated with low total serum testosterone ( TT ) identified in several cross‐sectional studies and systemic analyses . There is a lack of consensus regarding what constitutes the lowest level of testosterone within the boundaries of normality . In this retrospective study , we sought to evaluate the effect of associated co‐morbidities on serum total testosterone ( TT ) level in men with type 2 diabetes DM , either with or without erectile dysfunction ( ED ) . Three hundred and ninety‐one patients were evaluated for erectile function  using an abridged , five‐item version of the International Index of Erectile Function‐5 . Measurements of TT , fasting lipid profile , blood sugar and glycated haemoglobin ( HbA1c ) were conducted . Penile hemodynamics was assessed using intracavernosal injection and penile duplex study .  Hypogonadism was found in 126 cases ( 33.2 % ) , and normal TT was observed in 254 ( 66.8 % ) . ED was detected in 119 cases in the hypogonadal group ( 94.4 % ) as compared to 155/254 ( 61.0 % ) in eugonadal group , P = 0.0001 . TT was lower in diabetic men with ED as compared to those with normal erectile function ( EF ) , 392.4 ± 314.9 versus 524.3 ± 140.2 ng dl−1 , respectively , P < 0.0001 . After exclusion of patients with hypertension and dyslipidaemia , 185 men were evaluated , and there was no difference in the mean TT level among men with ED 490.6 ± 498.2 ng dl−1 versus normal EF 540.6 ± 133.4 ng dl−1 although , HbA1c remained lower in men with normal erectile function . Receiver operating characteristic ( ROC ) curve of TT in men without associated co‐morbidities showed that EF was compromised at TT = 403.5 ng dl−1 or less . Sensitivity of 63.3 % and a specificity of 94.0 % were detected . At this level , ED was found in 33/38 ( 86.8 % ) men with TT 403.5 ng dl−1 , whereas ED was observed in 57/147 ( 38.8 % ) men with TT ≥ 403.5 ng dl−1 ( P < 0.0001 ) . We propose a cut‐off value of 403.5 ng dl−1 of TT blood levels as an indicator for initiation of testosterone replacement therapy in diabetic men with ED . Further prospect i ve controlled trials are recommended Transdermal testosterone ( T ) delivery represents an effective alternative to injectable and rogens . We studied 163 hypogonadal men who applied 5 , 7.5 , or 10 g And roGel ( T gel ) 1 % CIII per day for up to 42 months .  Efficacy data were presented in 123 subjects considered evaluable . Continuous And roGel treatment normalized mean serum T and free T levels . Mean serum 5alpha-dihydrotestosterone concentrations and 5alpha-dihydrotestosterone/T ratio slightly increased , mean serum estradiol/T ratio doubled , and mean serum FSH and LH levels were suppressed by T replacement . Sexual function and mood parameters improved rapidly and were maintained throughout T treatment . Lean body mass increased ( P = 0.0001 ) and fat mass decreased ( P = 0.0001 ) , and these changes were maintained with treatment but were not accompanied by significant increases in muscle strength . Increases in serum bone markers suggestive of increased bone formation were followed by gradual and progressive increases in bone mineral density more in the spine ( P = 0.0001 ) than the hip ( P = 0.0004 ) . Mild local skin irritation occurred in 12 subjects , result ing in discontinuation in only one subject . Except for the anticipated increase in hematocrit and hemoglobin , there were no clinical ly significant changes in blood counts or biochemistry . In three subjects with elevated serum prostate-specific antigen , prostate biopsies showed cancer . We conclude that continued application of And roGel result ed in beneficial effects similar to those with injectables and other transdermal preparations . This study was neither placebo controlled nor powered to determine the effects of T treatment on prostate cancer risk . Thus , monitoring for prostatic disease and assessment for erythrocytosis are strongly advised to reduce the risk of adverse events with T treatment of hypogonadal men CONTEXT Risk factors for low testosterone and symptomatic and rogen deficiency ( AD ) may be modifiable . OBJECTIVE Our objective was to examine demographic , anthropometric , and medical correlates of low testosterone and symptomatic AD . DESIGN Data were used from the Boston Area Community Health Survey , an epidemiological study conducted from 2002 - 2005 . SETTING Data were obtained from a community-based r and om sample of racially and ethnically diverse men . PATIENTS OR OTHER PARTICIPANTS Data were available for 1822 men . MAIN OUTCOME MEASURES Multivariate logistic regression  was used to estimate odds ratios ( OR ) and 95 % confidence intervals ( CI ) for associations of covariates with 1 ) low testosterone and 2 ) symptomatic AD . The operational definition of low testosterone was serum total testosterone less than 300 ng/dl and free testosterone less than 5 ng/dl ; symptomatic AD was defined as the additional presence of symptoms : any of low libido , erectile dysfunction , or osteoporosis or two or more of sleep disturbance , depressed mood , lethargy , or diminished physical performance . RESULTS Factors associated with low testosterone included age ( OR = 1.36 ; 95 % CI= 1.11 - 1.66 , per decade ) , low per-capita income ( $ 6000 or less per household member vs. more than $ 30,000 ; OR = 2.86 ; 95 % CI = 1.39 - 5.87 ) , and waist circumference ( per 10-cm increase ; OR = 1.75 ; 95 % CI = 1.45 - 2.12 ) . Only age ( OR = 1.36 ; 95 % CI = 1.04 - 1.77 ) , waist circumference ( OR = 1.88 ; 95 % CI = 1.44 - 2.47 ) , and health status ( OR = 0.21 ; 95 % CI = 0.05 - 0.92 , excellent vs. fair/poor ) were associated with our construct of symptomatic AD . Of all variables , waist circumference was the most important contributor in both models . CONCLUSIONS Waist circumference is a potentially modifiable risk factor for low testosterone and symptomatic AD . Manifestation of symptoms may be a consequence of generally poor health status You are back where we put you in the previous article1 on diagnostic tests in this series on how to use the medical literature : in the library study ing an article that will guide you in interpreting ventilation-perfusion ( V/Q ) lung scans . Using the criteria in Table 1 , you have decided that the Prospect i ve Investigation of Pulmonary Diagnosis ( PIOPED ) study 2 will provide you with valid information . Just then , another
target: INTERPRETATION We found weak correlation between signs , symptoms and testosterone levels , uncertainty about what threshold testosterone levels should be considered low for aging men and wide variation in estimated prevalence of the condition .
  It is therefore difficult to extrapolate the method of diagnosing pathologic hypogonadism in younger men to clinical decisions regarding age-related testosterone decline in aging men
background: BACKGROUND Physicians diagnose and treat suspected hypogonadism in older men by extrapolating from the defined clinical entity of hypogonadism found in younger men .
  We conducted a systematic review to estimate the accuracy of clinical symptoms and signs for predicting low testosterone among aging men .