How to recognize late-onset hypogonadism in men with sexual dysfunction

Abstract

Late-onset hypogonadism (LOH) has been considered the most common form of male hypogonadism with a prevalence of approximately 1 in 100 men. Diagnosis of LOH should be made in symptomatic men with unequivocally low serum testosterone (T) levels. However, its clinical presentation is often insidious and difficult to recognize because it is characterized by nonspecific symptoms that make differential diagnosis with physiological ageing problematic. Sexual dysfunction is the most important determinant for medical consultation and the most specific symptom associated with low T. We therefore analysed a consecutive series of 1734 subjects who attended our unit for sexual dysfunction to investigate the associations between low T (different thresholds), sexual parameters, medical history data (delayed puberty, pituitary disease or cryptorchidism) and their physical exam results. Metabolic parameters, in particular waist circumference, display the greatest accuracy in detecting low T. We found that only the association of several symptoms and signs could significantly raise the clinical suspicion of low T. Structured inventories, which cluster together symptoms and signs of hypogonadism, can help clinicians suspect androgen deficiency. In particular, structured interviews, such as ANDROTEST, have been demonstrated to have a greater accuracy when compared to self reported questionnaires in detecting low T levels.

Figure 1

Conditions with a high prevalence of low testosterone levels for which measurement of serum testosterone levels is advisable.

Figure 2

Relevant metrics in patients' medical and sexual histories for detecting mild (<12 nmol l⁻¹) and severe (<8 nmol l⁻¹) hypogonadism in a consecutive series of 1734 patients that attended our unit seeking medical care for sexual dysfunction between 2002 and 2010. Data are reported in a log scale as age-adjusted hazard ratio (95% confidence intervals) stratified by age (<53 years old (a) and ≥53 years old(b)).

Figure 3

Relevant items in sexual history for detecting mild (<12 nmol l⁻¹) and severe (<8 nmol l⁻¹) hypogonadism in a consecutive series of 1734 patients that attended our unit seeking medical care for sexual dysfunction between 2002 and 2010. Data are reported in a log scale as age-adjusted hazard ratio (95% confidence intervals) stratified by age (<53 years old (a) and ≥53 years old(b)).

Figure 4

Clinical, metabolic and instrumental metrics for detecting mild (<12 nmol l⁻¹) and severe (<8 nmol ⁻¹) hypogonadism in a consecutive series of 1734 patients that attended our unit seeking medical care for sexual dysfunction between 2002 and 2010. Data are reported in a log scale as age-adjusted hazard ratio (95% confidence intervals) stratified by age (<53 years old (a) and ≥53 years old(b)). NCEP-ATPIII, National Cholesterol Education Program's Adult Treatment Panel III; PSV, peak systolic velocity at penile Doppler ultrasound; T2DM, type 2 diabetes mellitus.

Figure 5

Area under the curve (95% confidence intervals) derived from receiver-operating characteristic (ROC) curves for severe (total testosterone (TT)<8 nmol l⁻¹) or mild (TT<12 nmol ⁻¹) hypogonadism compared to different metrics derived from patients' medical and sexual history. Data are stratified by age (<53 years old (a) and ≥53 years old(b)).

Figure 6

Area under the curve (95% confidence intervals) derived from receiver-operating characteristic (ROC) curves for severe (total testosterone (TT)<8 nmol ⁻¹) or mild (TT<12 nmol l⁻¹) hypogonadism compared to different metrics derived from sexual history. Data are stratified by age (<53 years old (a) and ≥53 years old(b)).

Figure 7

Area under the curve (95% confidence intervals) derived from receiver-operating characteristic (ROC) curves for severe (total testosterone (TT)<8 nmol l⁻¹) or mild (TT<12 nmol l⁻¹) hypogonadism compared to different measurements derived from clinical, metabolic and instrumental items. Data are stratified by age (<53 years old (a) and ≥53 years old(b)). NCEP-ATPIII, National Cholesterol Education Program's Adult Treatment Panel III; PSV, peak systolic velocity; T2DM, type 2 diabetes mellitus.

Figure 8

ROC curves for severe hypogonadism (total testosterone (T)<8 nmol l⁻¹ or calculated free T according to Vermuelen's formula <225 pmol l⁻¹) in relation to ANDROTEST score. All data were derived from a consecutive series of subjects attending our unit from 2002 to 2010 seeking medical care for sexual dysfunction. Total T and calculated free T were available for 1734 and 1467 subjects, respectively.