Key points

Introduction

Lower urinary tract symptoms (LUTS) are a frequently encountered constellation of symptoms that consist of deviations from the usual storage and emptying functions of the lower urinary tract. The term male lower urinary tract symptoms describes an older male presenting with LUTS and implies no particular cause of these symptoms. This index patient has been depicted as a middle-aged or elderly man (often >50 years) with bothersome dysfunction of urinary storage, voiding, and/or the postmicturition period that often consists of a combination of frequency, urgency, nocturia, as well as hesitancy, weak stream, and feeling of incomplete emptying. Because an enlarged prostate gland that causes obstruction of the urinary outflow is the most likely cause of these symptoms, the term benign prostatic hyperplasia (BPH) has historically been attached to these symptoms. More recently, the terms benign prostatic enlargement (BPE) and benign prostatic obstruction (BPO) have largely taken the place of BPH, a term limited to the histologic proliferation of smooth muscle and epithelial cells in the prostate gland. It is difficult to define what characterizes clinically significant MLUTS, but patient-reported bother certainly plays the central role in clinical decision making. Because bother, prostate size, and urodynamically proven outflow obstruction are not always well correlated, it is not possible to make assumptions that LUTS occurring in men are explained by BPO caused by BPE. Therefore, the identification of causes of non-BPO MLUTS is a key component of each step of the evaluation of these patients. For the purposes of this article, all patients who present like the index patient are considered: with bothersome MLUTS without known cause, but statistically likely to be caused by BPO. Although the focus is on the role of urodynamics (UDS) in adding value to the evaluation of the patient with MLUTS suggestive of BPO, the value of UDS in identifying other causes of LUTS is also considered.

Describing the epidemiology and natural history of the problem of MLUTS is somewhat complicated by the way in which MLUTS is defined because of the use of data from studies of patients with BPH. There are biases present when extrapolating data from clinical trial populations, and testing for BPE, BPO, or histologic BPH would be invasive and costly; therefore, prostate and/or outlet obstruction is not necessarily the cause of LUTS in all patients in these calculations. It is reasonable to examine the efficiency and effectiveness of care for patients with MLUTS by starting with the evaluation of an undifferentiated symptomatic index patient, not the patient with definitive MLUTS with BPO. It is accepted that MLUTS is a common problem that deserves our attention. In the United States, moderate to severe LUTS was approximated to occur in 6.7 million of the 27 million men aged 50 to 79 years in the year 2000. In the United Kingdom between 1992 and 2001, the prevalence of LUTS in a general practice population was around 3.5% for men in their 40s , increasing to greater than 30% for men older than 85 years. In Sweden, a population study of 40,000 men aged 45 to 79 years showed 18.5% of men having moderate symptoms and 4.8% having severe LUTS. Wei and colleagues also note that the significant variation in the management of patients with MLUTS is a concern for the quality of care for this condition.

The focus on when UDS is necessary in MLUTS and how it is used boils down to the value that these studies add for shared decision making with patients and for determining the effectiveness of therapy. Educating patients on the various tradeoffs within treatment choices helps meet the objectives for treating MLUTS: improving patients’ quality of life by relief of bothersome symptoms, avoiding morbidity, and potentially slowing disease progression. Ideally, each individual could be accurately diagnosed, the outcomes of conservative management or active treatments could be predicted, and the chance of success could be maximized while minimizing adverse events, costly repeat evaluations, re-treatment, and failures—thus theoretically improving both patient and provider satisfaction. Avoiding the morbidities of BPO including acute or chronic urinary retention, the need for catheterization, and the attendant problems therein, urinary tract infections (UTIs), obstructive uropathy, and urinary calculi should also be considered benefits of appropriate treatment. The authors’ objective is to define the role of UDS in the current diagnostic algorithm and treatment of MLUTS in general, and especially MLUTS that is nonneurogenic, not associated with malignancy or other comorbid conditions, and not caused by infection, trauma, medications, radiation, or surgery.

Clinical guidelines are a valuable source of aggregated data and current expert opinion on the evaluation and treatment of MLUTS. The American Urological Association (AUA) and has published updated guidelines in the past 3 years that discuss the role of UDS in the diagnosis and workup of MLUTS, especially in the context of BPO. The AUA/SUFU (Society of Urodynamics, Female Pelvic Mecidine and Urogenital Reconstruction) Guidelines on Urodynamics in Adults also addresses this issue. In addition, the 6th International Consultation on Urologic Diseases (ICUD) consensus document was developed in 2005 and later summarized by Abrams and colleagues providing the basis for many of the subsequent algorithms. It is useful to examine these guidelines and review the evidence that led to their adoption so that one can apply these guidelines to the appropriate populations in practice. These guidelines characterize the specific index patient to which they apply, and understanding when UDS is recommended and also where patients come to intervention points with multiple options in an algorithm, or fall off the algorithm altogether, can help define when urodynamic evaluations provide value.

The 6th International Consultation on New Developments in Prostate Cancer & Prostate Diseases took place in 2005, and the consensus document on “Male Lower Urinary Tract Dysfunction: Evaluation and Management” was published in 2006 and summarized by Abrams and colleagues in 2009. The guidelines on “Evaluation and Treatment of Lower Urinary Tract Symptoms in Older Men” delineate a basic evaluation of the index patient including history, assessment of symptoms and bother, physical examination and digital rectal examination, urinalysis, serum prostate-specific antigen levels, and frequency-volume charts. For patients considering active treatment, the panel also recommends symptom quantification with validated questionnaires (I-PSS, ICIQ-MLUTS, and DAN-PSS-1), flow rate recording, postvoid residual (PVR), prostate imaging via ultrasonography, upper tract imaging and endoscopy under certain circumstances, and pressure flow studies (PFSs), which are recommended before invasive therapy in men with a maximum urinary flow rate (Q _max ) greater than 10 mL/s. The argument made is that flow rates above this level raise suspicion of causes of LUTS other than obstruction and patients who do not have obstruction are less likely to benefit from outlet reduction procedures.

The AUA guidelines on the Management of Benign Prostatic Hyperplasia (BPH) have undergone multiple revisions since they were initially presented in 1994, most recently in 2010, and are available at www.auanet.org/content/guidelines-and-quality-care/clinical-guidelines.cfm?sub=bph . The algorithms presented in the guidelines were adopted from the ICUD document and again include the use of PFSs when the patient is being offered minimally invasive or invasive surgical treatment and the evaluation does not clearly indicate obstruction, that is, the maximum flow rate on uroflowmetry is greater than 10 mL/s. The committee notes that PFSs are an optional part of the evaluation, which categorizes their use as having the highest level of flexibility with regard to application of guideline statements.

The AUA also addresses MLUTS in the AUA/SUFU Guidelines on Urodynamics in Adults. The panel recommends uroflowmetry for the initial diagnosis and ongoing management of MLUTS with a grade C level of evidence and makes note of the pitfall of variability of the measurements, as well as the risks of false positives and false negatives. The panel separately addresses cystometry and PFSs. Multichannel filling cystometry is noted to have little evidence for use in the management of patients with LUTS, with expert opinion cited as the basis for recommending that cystometry may be performed to identify detrusor overactivity (DO) or poor compliance when invasive/irreversible treatments are being considered. The panel recommends PFSs as a standard with grade B evidence, stating that they should be performed when diagnosing obstruction is important, especially when considering invasive treatment. The panel notes that the current scientific evidence, although not without variability, does point to PFS-confirmed obstruction as a predictor of improved outcomes from treatment. The guideline also specifies that the urodynamic study itself should be discussed with the patient with regard to its benefits, shortcomings, and possible complications.

The European Association of Urology (EAU) had previously published guidelines under the title “Assessment, Therapy and Follow-Up of Men with Lower Urinary Tract Symptoms Suggestive of Benign Prostatic Obstruction (BPH Guidelines).” These were most recently updated in 2013 and summarized by Oelke and colleagues in their article “EAU Guidelines on the Treatment and Follow-up of Non-neurogenic Male Lower Urinary Tract Symptoms Including Benign Prostatic Obstruction.” The updated document takes a symptom- and treatment-based approach and does not delineate specific guidelines regarding the workup of patients with MLUTS.

McNicholas and colleagues convey a similar outlook in Campbell-Walsh Urology, Tenth Edition : “If the initial evaluation, flow rate, and PVR urine volume are not sufficiently suggestive of BOO, further urodynamic assessment by PFSs should be considered, especially if an invasive treatment is considered (ie, surgery) or if surgical treatment has failed.”

Describing the pathophysiology of MLUTS and the details of each of the treatment options available is beyond the scope of this article; however, in the context of choosing when to use UDS evaluations, the article discusses how to define and diagnose the cause of the symptoms of MLUTS and how treatment outcomes have been evaluated using urodynamic data.

Introduction

Lower urinary tract symptoms (LUTS) are a frequently encountered constellation of symptoms that consist of deviations from the usual storage and emptying functions of the lower urinary tract. The term male lower urinary tract symptoms describes an older male presenting with LUTS and implies no particular cause of these symptoms. This index patient has been depicted as a middle-aged or elderly man (often >50 years) with bothersome dysfunction of urinary storage, voiding, and/or the postmicturition period that often consists of a combination of frequency, urgency, nocturia, as well as hesitancy, weak stream, and feeling of incomplete emptying. Because an enlarged prostate gland that causes obstruction of the urinary outflow is the most likely cause of these symptoms, the term benign prostatic hyperplasia (BPH) has historically been attached to these symptoms. More recently, the terms benign prostatic enlargement (BPE) and benign prostatic obstruction (BPO) have largely taken the place of BPH, a term limited to the histologic proliferation of smooth muscle and epithelial cells in the prostate gland. It is difficult to define what characterizes clinically significant MLUTS, but patient-reported bother certainly plays the central role in clinical decision making. Because bother, prostate size, and urodynamically proven outflow obstruction are not always well correlated, it is not possible to make assumptions that LUTS occurring in men are explained by BPO caused by BPE. Therefore, the identification of causes of non-BPO MLUTS is a key component of each step of the evaluation of these patients. For the purposes of this article, all patients who present like the index patient are considered: with bothersome MLUTS without known cause, but statistically likely to be caused by BPO. Although the focus is on the role of urodynamics (UDS) in adding value to the evaluation of the patient with MLUTS suggestive of BPO, the value of UDS in identifying other causes of LUTS is also considered.

Describing the epidemiology and natural history of the problem of MLUTS is somewhat complicated by the way in which MLUTS is defined because of the use of data from studies of patients with BPH. There are biases present when extrapolating data from clinical trial populations, and testing for BPE, BPO, or histologic BPH would be invasive and costly; therefore, prostate and/or outlet obstruction is not necessarily the cause of LUTS in all patients in these calculations. It is reasonable to examine the efficiency and effectiveness of care for patients with MLUTS by starting with the evaluation of an undifferentiated symptomatic index patient, not the patient with definitive MLUTS with BPO. It is accepted that MLUTS is a common problem that deserves our attention. In the United States, moderate to severe LUTS was approximated to occur in 6.7 million of the 27 million men aged 50 to 79 years in the year 2000. In the United Kingdom between 1992 and 2001, the prevalence of LUTS in a general practice population was around 3.5% for men in their 40s , increasing to greater than 30% for men older than 85 years. In Sweden, a population study of 40,000 men aged 45 to 79 years showed 18.5% of men having moderate symptoms and 4.8% having severe LUTS. Wei and colleagues also note that the significant variation in the management of patients with MLUTS is a concern for the quality of care for this condition.

The focus on when UDS is necessary in MLUTS and how it is used boils down to the value that these studies add for shared decision making with patients and for determining the effectiveness of therapy. Educating patients on the various tradeoffs within treatment choices helps meet the objectives for treating MLUTS: improving patients’ quality of life by relief of bothersome symptoms, avoiding morbidity, and potentially slowing disease progression. Ideally, each individual could be accurately diagnosed, the outcomes of conservative management or active treatments could be predicted, and the chance of success could be maximized while minimizing adverse events, costly repeat evaluations, re-treatment, and failures—thus theoretically improving both patient and provider satisfaction. Avoiding the morbidities of BPO including acute or chronic urinary retention, the need for catheterization, and the attendant problems therein, urinary tract infections (UTIs), obstructive uropathy, and urinary calculi should also be considered benefits of appropriate treatment. The authors’ objective is to define the role of UDS in the current diagnostic algorithm and treatment of MLUTS in general, and especially MLUTS that is nonneurogenic, not associated with malignancy or other comorbid conditions, and not caused by infection, trauma, medications, radiation, or surgery.

Clinical guidelines are a valuable source of aggregated data and current expert opinion on the evaluation and treatment of MLUTS. The American Urological Association (AUA) and has published updated guidelines in the past 3 years that discuss the role of UDS in the diagnosis and workup of MLUTS, especially in the context of BPO. The AUA/SUFU (Society of Urodynamics, Female Pelvic Mecidine and Urogenital Reconstruction) Guidelines on Urodynamics in Adults also addresses this issue. In addition, the 6th International Consultation on Urologic Diseases (ICUD) consensus document was developed in 2005 and later summarized by Abrams and colleagues providing the basis for many of the subsequent algorithms. It is useful to examine these guidelines and review the evidence that led to their adoption so that one can apply these guidelines to the appropriate populations in practice. These guidelines characterize the specific index patient to which they apply, and understanding when UDS is recommended and also where patients come to intervention points with multiple options in an algorithm, or fall off the algorithm altogether, can help define when urodynamic evaluations provide value.

The 6th International Consultation on New Developments in Prostate Cancer & Prostate Diseases took place in 2005, and the consensus document on “Male Lower Urinary Tract Dysfunction: Evaluation and Management” was published in 2006 and summarized by Abrams and colleagues in 2009. The guidelines on “Evaluation and Treatment of Lower Urinary Tract Symptoms in Older Men” delineate a basic evaluation of the index patient including history, assessment of symptoms and bother, physical examination and digital rectal examination, urinalysis, serum prostate-specific antigen levels, and frequency-volume charts. For patients considering active treatment, the panel also recommends symptom quantification with validated questionnaires (I-PSS, ICIQ-MLUTS, and DAN-PSS-1), flow rate recording, postvoid residual (PVR), prostate imaging via ultrasonography, upper tract imaging and endoscopy under certain circumstances, and pressure flow studies (PFSs), which are recommended before invasive therapy in men with a maximum urinary flow rate (Q _max ) greater than 10 mL/s. The argument made is that flow rates above this level raise suspicion of causes of LUTS other than obstruction and patients who do not have obstruction are less likely to benefit from outlet reduction procedures.

The AUA guidelines on the Management of Benign Prostatic Hyperplasia (BPH) have undergone multiple revisions since they were initially presented in 1994, most recently in 2010, and are available at www.auanet.org/content/guidelines-and-quality-care/clinical-guidelines.cfm?sub=bph . The algorithms presented in the guidelines were adopted from the ICUD document and again include the use of PFSs when the patient is being offered minimally invasive or invasive surgical treatment and the evaluation does not clearly indicate obstruction, that is, the maximum flow rate on uroflowmetry is greater than 10 mL/s. The committee notes that PFSs are an optional part of the evaluation, which categorizes their use as having the highest level of flexibility with regard to application of guideline statements.

The AUA also addresses MLUTS in the AUA/SUFU Guidelines on Urodynamics in Adults. The panel recommends uroflowmetry for the initial diagnosis and ongoing management of MLUTS with a grade C level of evidence and makes note of the pitfall of variability of the measurements, as well as the risks of false positives and false negatives. The panel separately addresses cystometry and PFSs. Multichannel filling cystometry is noted to have little evidence for use in the management of patients with LUTS, with expert opinion cited as the basis for recommending that cystometry may be performed to identify detrusor overactivity (DO) or poor compliance when invasive/irreversible treatments are being considered. The panel recommends PFSs as a standard with grade B evidence, stating that they should be performed when diagnosing obstruction is important, especially when considering invasive treatment. The panel notes that the current scientific evidence, although not without variability, does point to PFS-confirmed obstruction as a predictor of improved outcomes from treatment. The guideline also specifies that the urodynamic study itself should be discussed with the patient with regard to its benefits, shortcomings, and possible complications.

The European Association of Urology (EAU) had previously published guidelines under the title “Assessment, Therapy and Follow-Up of Men with Lower Urinary Tract Symptoms Suggestive of Benign Prostatic Obstruction (BPH Guidelines).” These were most recently updated in 2013 and summarized by Oelke and colleagues in their article “EAU Guidelines on the Treatment and Follow-up of Non-neurogenic Male Lower Urinary Tract Symptoms Including Benign Prostatic Obstruction.” The updated document takes a symptom- and treatment-based approach and does not delineate specific guidelines regarding the workup of patients with MLUTS.

McNicholas and colleagues convey a similar outlook in Campbell-Walsh Urology, Tenth Edition : “If the initial evaluation, flow rate, and PVR urine volume are not sufficiently suggestive of BOO, further urodynamic assessment by PFSs should be considered, especially if an invasive treatment is considered (ie, surgery) or if surgical treatment has failed.”

Describing the pathophysiology of MLUTS and the details of each of the treatment options available is beyond the scope of this article; however, in the context of choosing when to use UDS evaluations, the article discusses how to define and diagnose the cause of the symptoms of MLUTS and how treatment outcomes have been evaluated using urodynamic data.