Urinary symptoms: prevalence and severity in British men aged 55 and over

The global burden of lower urinary tract symptoms suggestive of benign prostatic hyperplasia: A systematic review and meta-analysis

Benign prostatic hyperplasia is a common non-malignant condition among older men, but the epidemiology is poorly characterised. We summarised and determined the global prevalence of benign prostatic hyperplasia. A systematic search on PubMed, EMBASE and CENTRAL was performed up until 31^st July 2016. Studies that described the epidemiology of benign prostatic hyperplasia were included and cumulative plots of prevalence estimates were calculated. A total of 31 prevalence rate estimates from 25 countries were identified. The combined prevalence estimates showed that the lifetime prevalence of BPH was 26.2% (95% CI: 22.8–29.6%). We found that there was an increasing prevalence of BPH with age. However, we found no significant difference between (a) rural, urban or mixed sites, (b) different countries, (c) respondent representativeness. (d) sample size or (e) study quality. We also found no significant change in the prevalence over the past 20 years. While there is substantial variation between sites estimates, results suggest that nearly 1 in 4 men will suffer from BPH over their lifetime. The study revealed there are significant gaps in knowledge, which provides opportunities for future research to further enrich the epidemiological landscape with data.

Burden of male lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) - focus on the UK

KEY MESSAGES

Lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) can be bothersome and negatively impact on a patient's quality of life (QoL). As the prevalence of LUTS/BPH increases with age, the burden on the healthcare system and society may increase due to the ageing population. This review unifies literature on the burden of LUTS/BPH on patients and society, particularly in the UK. LUTS/BPH is associated with high personal and societal costs, both in direct medical costs and indirect losses in daily functioning, and through its negative impact on QoL for patients and partners. LUTS/BPH is often underdiagnosed and undertreated. Men should be encouraged to seek medical advice for this condition and should not accept it as part of ageing, while clinicians should be more active in the identification and treatment of LUTS/BPH. To assess the burden of illness and unmet need arising from lower urinary tract symptoms (LUTS) presumed secondary to benign prostatic hyperplasia (BPH) from an individual patient and societal perspective with a focus on the UK. Embase, PubMed, the World Health Organization, the Cochrane Database of Systematic Reviews and the York Centre for Reviews and Dissemination were searched to identify studies on the epidemiological, humanistic or economic burden of LUTS/BPH published in English between October 2001 and January 2013. Data were extracted and the quality of the studies was assessed for inclusion. UK data were reported; in the absence of UK data, European and USA data were provided. In all, 374 abstracts were identified, 104 full papers were assessed and 33 papers met the inclusion criteria and were included in the review. An additional paper was included in the review upon a revision in 2014. The papers show that LUTS are common in the UK, affecting ≈3% of men aged 45-49 years, rising to >30% in men aged ≥85 years. European and USA studies have reported the major impact of LUTS on quality of life of the patient and their partner. LUTS are associated with high personal and societal costs, both in direct medical costs and indirect losses in daily functioning. While treatment costs in the UK are relatively low compared with other countries, the burden on health services is still substantial. LUTS associated with BPH is a highly impactful condition that is often undertreated. LUTS/BPH have a major impact on men, their families, health services and society. Men with LUTS secondary to BPH should not simply accept their symptoms as part of ageing, but should be encouraged to consult their physicians if they have bothersome symptoms.

Measuring the psychosocial impact of population-based prostate-specific antigen testing for prostate cancer in the UK

OBJECTIVE

To evaluate the psychosocial impact of participation in a population-based prostate-specific antigen (PSA) testing programme, akin to screening, and to explore the relationship between urinary symptoms reported before PSA testing and the response to the subsequent PSA result.

PATIENTS AND METHODS

This prospective questionnaire study was nested within the case-finding component of the ProtecT (prostate testing for cancer and treatment) feasibility study (ISRCTN20141297). Men aged 50-69 years from 18 general practices in three cities in the UK completed the Hospital Anxiety and Depression Scale (HADS), the Short Form-12 (SF-12) Health Survey, and the International Continence Society 'male' (ICSmale) questionnaires before giving consent for a PSA test in a community clinic (baseline). Men with an 'abnormal' PSA result returned for further investigation (including biopsy) and repeated these questionnaires before biopsy.

RESULTS

At baseline, study participants had similar levels of anxiety and depression to the general male population. There was no increase in the HADS scores, or reduction in the SF-12 mental health component summary score, on attendance at the biopsy clinic after receiving an 'abnormal' PSA result. Urinary symptoms were associated with levels of anxiety and depression before receiving a PSA result (baseline), but were not associated with anxiety and depression at biopsy independently of baseline scores. Therefore changes in anxiety or depression at biopsy did not appear to differ between those with and without urinary symptoms.

CONCLUSIONS

This study confirms the findings of other studies that the deleterious effects of receiving an abnormal PSA result during population screening are not identified by generic health-status questionnaires. Comparisons with outcomes of studies measuring cancer-specific distress and using qualitative research methods raise the question of whether a prostate cancer screening-specific instrument is required. However, a standardized measure of anxiety identified differences at baseline between those who did and did not report urinary symptoms. These findings suggest that it might be advisable to better inform men undergoing PSA testing about the uncertain relationship between urinary symptoms and prostate cancer, to minimize baseline levels of psychological distress.

Incidence, prevalence and management of lower urinary tract symptoms in men in the UK

OBJECTIVE

To describe the incidence, prevalence and management of lower urinary tract symptoms (LUTS), suggestive of benign prostatic hyperplasia, reported in UK general practice.

PATIENTS AND METHODS

All clinical information relating to LUTS and its treatment was assessed for men aged > or = 45 years and registered on the UK General Practice Research Database (GPRD) at some time between 1992 and 2001. Incidence and prevalence were derived from the GPRD population. Secular trends in the management of LUTS were examined from prescribing rates and the intervals between first symptoms, first treatment and surgery or catheterization.

RESULTS

The incidence of reported LUTS showed a strong linear increase with age. The prevalence increased from 3.5% for men aged 45-49 years to > 30% for men aged > 85 years. Between 1992 and 2000 there was a five-fold increase in the proportion of time with LUTS when men were receiving medical treatment. This was accompanied by a progressive decrease in the intervals between first symptoms and first drug treatment, and a significant increase in the intervals from first symptoms or first treatment to surgery or catheterization. Treated men received surgery or catheterization significantly later than those receiving no drug treatment.

CONCLUSION

There has been a significant increase in the use of medical therapy for LUTS over the last decade. The accompanying postponement of surgery/catheterization is likely to be a result, at least in part, of successful earlier medical treatment and the treatment of a greater proportion of symptomatic men.

Symptomatic diagnosis of prostate cancer in primary care: a structured review

BACKGROUND

Prostate cancer has the second highest cancer incidence and mortality in European men. Most prostate cancers are diagnosed after lower urinary tract symptoms (LUTS) are presented to primary care, but such symptoms more often have a benign cause. A general practitioner (GP) has to try and identify which of these patients have prostate cancer.

AIMS

To review the presenting features of symptomatic prostate cancer.

DESIGN OF STUDY

Structured review.

METHOD

We searched Medline from 1980 to 2003 for symptoms, signs, and investigations reported in prostate cancer. This list was then expanded by secondary searches of reference lists. We excluded studies on post-diagnostic topics, such as staging, treatment, and prognosis; studies on non-Western patients; and studies on investigations that are not available in primary care. A second cycle of exclusions removed studies whose results would not guide a GP in deciding whether a patient has prostate cancer.

RESULTS

No studies from primary care compared prostate cancer patients directly with controls. Two secondary care studies had enough information to allow a comparison of symptoms in cases compared with controls. In these studies, symptoms were generally more prevalent in cases, but the differences were small. Screening and secondary care studies suggest that early prostate cancer is symptomless, and that locally advanced cancer has LUTS that are similar to those for benign prostatic hypertrophy.

CONCLUSION

There is a very weak evidence base for the primary care diagnosis of prostate cancer in men with lower urinary tract symptoms.

Could self-management challenge pharmacotherapy as a long-term treatment for uncomplicated lower urinary tract symptoms?

PURPOSE OF REVIEW

This review highlights the lifestyle and behavioural management strategies (self-management) available to men with lower urinary tract symptoms.

RECENT FINDINGS

Pharmacotherapy has evolved considerably over the last decade and now most men with lower urinary tract symptoms are treated at some point with either single or combined therapy. However, recent studies reporting the longer term usage of pharmacotherapy have shown significantly high rates of discontinuation due to patient compliance, treatment ineffectiveness, side effects and patient choice. Not all these men will require or desire surgery. For those with bothersome symptoms self-management may be an effective strategy. Self-management interventions include education, reassurance, fluid management, caffeine avoidance, rescheduling concurrent medications and bladder retraining. As in other chronic disease areas such as diabetes and arthritis for which self-management is well established, lifestyle and behavioural interventions for men with lower urinary tract symptoms aim to allow the patient some day-to-day control over their symptoms. These interventions have been shown to be in wide use in the UK without good quality supporting evidence, suggesting that they are thought to be safe and effective.

SUMMARY

Self-management (lifestyle and behavioural) interventions provide men with some control over their symptoms, their role as either a primary treatment strategy or to augment pharmacotherapy has yet to be defined.

Diagnosis and treatment of voiding symptoms

Lower urinary tract symptoms (LUTS) are associated with lower urinary tract dysfunction. Symptoms are the subjective indicator of a disease or change in condition as perceived by the patient, caregiver, or partner and may lead the individual to seek help from health care professionals. LUTS are usually qualitative and, therefore, cannot usually be used to make a definitive diagnosis. LUTS also can indicate pathologies other than lower urinary tract dysfunction, such as urinary infection. LUTS are divided into 7 groups: storage, voiding (obstructive), postmicturition symptoms and 4 others. Voiding symptoms, which are caused by lower urinary tract obstruction, include slow stream, splitting or spraying, intermittency, hesitancy, straining, and terminal dribble. Postmicturition symptoms, which are experienced immediately after micturition, consist of the feeling of incomplete emptying and postmicturition dribble. Postmicturition dribble describes the involuntary loss of urine immediately after the individual has finished passing urine; in men, usually after leaving the toilet and in women, after rising from the toilet. Hence, postmicturition dribble is elicited by different situations or is considered as having different implications. For example, although postmicturition dribble usually implies incomplete emptying (voiding symptoms) in elderly men with benign prostatic hyperplasia, postmicturition dribble is often considered as urinary incontinence (a storage symptom) in many patients, even with bladder outlet obstruction. In such cases, detailed history taking and further evaluation, such as urinary flowmetry, postvoid residual volume, and comprehensive urodynamic evaluation, should be performed as appropriate. If no urodynamic abnormalities of either the detrusor or the outlet can be detected despite significant LUTS, factors unrelated to the lower urinary tract may be responsible for the voiding symptoms.

The fear of prostate cancer in men with lower urinary tract symptoms: should symptomatic men be screened?

OBJECTIVE

To explore the concerns and worries in men with uncomplicated lower urinary tract symptoms (LUTS, but no evidence of prostate cancer) relating to their symptoms.

PATIENTS AND METHODS

There is no current prostate cancer screening programme in the UK. Evidence suggests that men with LUTS have the same risk of prostate cancer as aged-matched asymptomatic men. However, most men with LUTS are 'screened' with a digital rectal examination (DRE) and prostate specific antigen (PSA) testing as part of routine assessment. Whether this screening offers any benefit to patients and whether national screening for prostate cancer and subsequent early treatment offer any long-term survival or quality of life benefit is uncertain. Thus 30 men with uncomplicated LUTS were qualitatively interviewed to explore their concerns and worries about their symptoms. Interviews were transcribed verbatim and subjected to content analysis using validated techniques.

RESULTS

Of the 30 men, 22 (73%) expressed a fear of prostate cancer at the time of their initial presentation. This fear was independent of race, social class and symptom severity; older men were less worried. Of the 22, 15 (68%) stated that after reassurance their symptoms were less bothersome and easier to cope with.

CONCLUSIONS

These findings suggest there is a considerable gain in health by explicitly addressing the concerns of prostate cancer in men with uncomplicated LUTS. Informing these men of their true risk of prostate cancer (before or after a DRE and PSA estimate) may alleviate much of the bother associated with their symptoms. Despite no evidence of any greater risk of prostate cancer than in asymptomatic men, symptomatic men should continue to be screened after appropriate counselling.

The psychological effects of treatments for lower urinary tract symptoms

OBJECTIVE

To assess and evaluate the level of depression, anxiety and psychiatric status in patients with lower urinary tract symptoms (LUTS) before and after treatment by surgery or drugs.

PATIENTS AND METHODS

The study included 123 patients (mean age 64.6 years, SD 7. 95) with LUTS who were treated medically (with alpha-blockers, i.e. terazosin, prazosin, doxazosin and alfuzosin), and 52 patients (mean age 69.6 years, SD 7.94) with LUTS and confirmed to have benign prostatic hyperplasia (BPH) who underwent transurethral resection of the prostate (TURP). Both groups were assessed at baseline and 3 months after treatment using standardized questionnaires (the Beck Depression Inventory, the State-Trait Anxiety Inventory and the General Health Questionnaire-12).

RESULTS

Patients before TURP were significantly more depressed, worried and psychiatrically morbid than were those before medical treatment. Three months after medical and surgical treatment, there was significantly less depression, anxiety and psychiatric morbidity in the TURP than in the medication group.

CONCLUSIONS

TURP is a better treatment than medication for minimising anxiety, depression and psychiatric morbidity after treatment in patients with LUTS, but causes greater psychological stress before treatment.

Epidemiology and classification of urinary incontinence

Urinary incontinence is a common symptom affecting the physical, psychological, social and economic well-being of individuals and their families. It also poses a considerable economic burden on health and social services. The literature reports widely varying prevalence rates for incontinence that are partially explained by methodological differences between studies. However, community-based studies indicate that approximately 6% of the population, particularly women and older people, will have urinary incontinence of sufficient severity to interfere with their quality of life. This represents a significant demand for health care. Although further research on prevalence is unlikely to add anything new to current knowledge on the size of the problem, more information is needed on the onset, progression and risk factors of urinary incontinence to inform methods of effective treatment and preventive strategies. In addition, there has been little investigation of the triggers to seeking professional help or of the response of health professionals to patients' demands for treatment, either for incontinence or other lower urinary tract symptoms. The aetiology of incontinence is multifactorial; incontinence is caused by pathophysiological impairments to the lower urinary tract and neurological system, as well as a range of external factors. The key to effective management, therefore, is a comprehensive assessment of the patient, including other lower urinary tract symptoms, so that appropriate intervention is tailored on a diagnosis and not on symptoms.

Estimating the "avoidable" burden of disease by Disability Adjusted Life Years (DALYs)

The World Bank's Global Burden of Disease Study pioneered the use of Disability Adjusted Life Years (DALYs). In this paper we distinguish between the total and the "avoidable" burden of disease. We identify different ways of measuring DALYs: incidence-based DALYs are appropriate where the means of reducing the burden of disease is by prevention; prevalence-based DALYs are appropriate when a disease cannot be prevented but effective treatment is available. The methods of estimating each are explained and we describe how we have applied these methods to seven causes of death and disability in the South and West Region. We discuss the relevance of this work for monitoring the health of populations and deciding how best to use scarce resources to improve health.

The prevalence of lower urinary tract symptoms in Austrian males and associations with sociodemographic variables

The aim of our study was to assess the prevalence of lower urinary tract symptoms (LUTS) in Austrian males and to correlate the findings with sociodemographic variables. In a population-based cross-sectional study in Austria in the year 1995, data on voiding symptoms were collected from a representative sample of men by using the International Prostate Symptom Score (IPSS). Only 28.6% of the males aged 15 to 89 years (total n = 939) reported no LUTS at all (IPSS = 0). In the group of males who report symptoms, a positive correlation of the IPSS with age is found. Furthermore IPSS correlates with weekly alcohol and nicotine consumption, but not with the respondent's body-mass index (BMI), educational status and monthly household income. The bothersomeness of LUTS increases with age, leaving more than 12% of the males aged 40 to 89 dissatisfied with urinary symptoms. Extrapolated to population numbers, more than 87,000 males in Austria (aged 15 to 89 years) would feel 'terribly' if they were to spend the rest of their lives with urinary symptoms as they were at the time of the survey. Due to an estimated future increase of the proportion of older people in Austria, the number of males with LUTS will rise significantly, thereby placing increased burden on medical resources in the future.

Prevalence of lower urinary tract symptoms in Finnish men: a population-based study

OBJECTIVE

To determine the prevalence of lower urinary tract symptoms (LUTS) in Finnish men, using a population-based cross-sectional survey.

SUBJECTS AND METHODS

In 1994, a modified Danish prostatic symptom score system (DAN-PSS-1) questionnaire on the occurrence and severity of LUTS was mailed to all men (3143) born in 1924, 1934 or 1944 living in the city of Tampere or 11 rural and semi-rural municipalities in the same county.

RESULTS

After exclusions, 68% of the men were ultimately included in the study. LUTS were common and increased with age so that the prevalence of at least one symptom was 89% in the whole population (84%) among 50-year-old, 91% among 60-year-old and 94% among 70-year-old men). Most of the symptoms were mild, with post-micturition dribbling and nocturia the most prevalent symptoms, and stress incontinence the least prevalent.

CONCLUSIONS

The high incidence of LUTS may indicate a high prevalence of benign prostatic enlargement secondary to benign prostatic hyperplasia, but other causes are also involved. With the increase in the mean age of the general population, the number of individuals with LUTS is likely to increase and must be considered when resources are planned for medical care.

Health-related quality of life associated with lower urinary tract symptoms in four countries

OBJECTIVES

To describe health-related quality of life (HRQL) associated with lower urinary tract symptoms (LUTS) assessed by validated questionnaires in four countries.

METHODS

More than 6000 men, recruited by using community- or population-based sampling in four countries, completed questionnaires soliciting information about urinary symptom frequency, bother, degree of interference with daily activities, and other measures of HRQL.

RESULTS

In all countries, disease-specific HRQL worsened with increasing age. Adjusting for age, most disease-specific HRQL measures were significantly worse with increasing symptom severity. The correlation between symptoms and HRQL was strongest in countries with higher prevalence of symptoms, such as Japan or the United States, and less pronounced in countries with lower prevalence (France, Scotland), possibly reflecting the lower variability in scores.

CONCLUSIONS

HRQL measures are worse in older men, and increased urinary symptom severity is associated with worse disease-specific HRQL in all countries, despite potential cross-cultural differences in disease prevalence, medication use, perceptions, or willingness to report symptoms or worse HRQL. This cross-cultural consistency suggests that an assessment of symptom bother or interference with daily activities may be useful in patient evaluation.

Quality of life in geriatric patients with lower urinary tract dysfunction

Lower urinary tract dysfunctions, such as urinary incontinence, detrusor instability, and benign prostatic hyperplasia, are prevalent in older adults. These conditions, which can occur alone or in combination, result in irritative or obstructive symptoms that can interfere with everyday functioning, leading to negative consequences on health-related quality of life. The nature and severity of these symptoms and the perception of their impact on daily activities can be quite variable. Until recently, relatively little was known about the effect of lower urinary tract dysfunctions on general health status and quality of life. An increasing research base is now available that shows the impact of different urologic dysfunctions in clinical and general populations. This article will provide a brief background on the definition and measurement of health-related quality of life and will summarize the literature about the quality of life of community-dwelling elderly patients with urinary incontinence or prostate conditions. Implications to guide clinical practice and future research will be derived.

Limitations of epidemiologically based needs assessment. The case of prostatectomy

OBJECTIVES

The aim of this study was to make epidemiologically based estimates of the prevalent and incident "need" for prostatectomy for lower urinary tract symptoms, defined as the numbers of men who would both benefit from and want the operation.

METHODS

The methods involved a consensus panel, a two-stage postal survey of 1,480 men aged 55 years or older from eight general practices to the northwest of London, United Kingdom, and a multistate life table.

RESULTS

The overall response rate was 69% (initial survey: 78%, follow-up survey: 88%). A trial-based estimate of number of candidates for prostatectomy (men with symptoms that were at least moderately severe and bothersome and who would probably or definitely want surgery) was 610 men in a population of 250,000. The corresponding incidence estimate (including men with symptoms recurring after spontaneous remission or surgery) was approximately 200 per year, including approximately 110 new cases. Consensus-based estimation, including categories of patients who have not yet been subject to a trial, gave much higher figures of approximately 3,000, 650, and 200 candidates, respectively. Adding the number of men who said they were "inclined to" choose surgery would almost double these figures.

CONCLUSIONS

Estimates of need were highly sensitive to choice of indications and assumptions about patients' attitudes toward surgery. Population needs assessment for specific procedures will always involve judgment as well as epidemiological data and modeling.

Challenges of monitoring use of secondary care at local level: a study based in London, UK

STUDY OBJECTIVE

To provide those working at district level with practical guidance on using hospital data linked to small geographic areas to explore patterns of care.

DESIGN

Examination of the association between age standardised hospital episode rates for the commonest diagnostic categories and deprivation levels (Carstairs index) of the electoral ward of residence.

SETTING

An inner London district, Kensington, Chelsea and Westminster, with a population of approximately 325,000.

POPULATION

All finished consultant episodes recorded in NHS hospitals for the district population in the year to April 1994.

MAIN RESULTS

Many, but not all, disease categories were associated strongly with deprivation, with high episode rates in the most deprived electoral wards. This is partly due to more of those in deprived areas being admitted to hospital and to them being admitted more often.

CONCLUSIONS

A wide range of factors needs to be taken into account in interpreting these data. They include the contribution of the private sector and artifacts of both the numerator and denominator. This paper provides a framework for those working at district level to begin to analyse the association between hospitalisation and deprivation locally. It also identifies some of the issues that must be taken into account when seeking to interpret these data.

The impact of lower urinary tract symptoms on general health status and on the use of prostatectomy

Our objective was to determine the extent to which lower urinary tract symptoms affect the general health status of men and contribute to the decision to undergo surgery. A cross-sectional population survey using postal questionnaires was conducted in the North West Thames health region, followed by a prospective cohort study of men undergoing prostatectomy (North West Thames and Oxford regions). The subjects in the first survey were 221 men aged 55 and over with previously reported mild, moderate or severe urinary symptoms; subjects in the second study were 388 men undergoing prostatectomy. Main outcome measures were self-reported symptom severity, bothersomeness and general health status (Nottingham Health Profile, Part 1). The response rate among eligible responders in the population survey was 85.7%. Increasing symptom severity was associated with worsening NHP scores for energy, emotional reactions, sleep and physical mobility (p < 0.01). Increasing bothersomeness of symptoms was associated with emotional reactions, sleep and pain (p < 0.05). Men undergoing surgery reported worse health status than men in the population with the same severity of symptoms as regards emotional reactions, energy and pain. For a given level of symptom severity, the impact of those symptoms on aspects of a man's general health status may be the determinant of seeking and undergoing surgery. Greater understanding of the factors that affect a man's response to his symptoms is needed in interpreting the decision to seek and accept treatment.

Health status and quality of life of British men with lower urinary tract symptoms: results from the SF-36

OBJECTIVES

To determine the extent to which urinary symptoms, and resulting bothersomeness interfere with daily activities and affect health status, as measured using the Medical Outcomes Study 36-item short form health survey (SF-36).

METHODS

Postal population survey in a British health region of 217 men aged 55 years and over known to have reported mild, moderate, or severe lower urinary tract symptoms. Outcome measures are self-reported urinary symptoms, their bothersomeness, general health status, and quality of life (measured using the SF-36).

RESULTS

Response rate among eligible subjects was 84%. Depending on the activity, between 9% and 49% of men with moderate or severe urinary symptoms reported interference with some of their daily activities. Increasing symptom severity was associated with worsening physical role, social functioning, vitality, mental health, and perception of general health, and increasing bothersomeness was associated with worsening of all dimensions of general health status and quality of life. The association between these measures and bothersomeness was stronger than with symptom score. Compared with the general population, men bothered by their symptoms to the extent that they were a medium or a large problem have worse health status for all dimensions except physical functioning.

CONCLUSIONS

The SF-36 demonstrates a deterioration in general health status and quality of life with increasing lower urinary tract symptoms and the extent to which those symptoms are bothersome. As such, it provides a generic measure of the burden of ill health arising from these symptoms at a population level. There is, however, considerable individual variation in the way that men respond to their symptoms.

International variation in intervention rates. What are the implications for patient selection?

While international variations in intervention rates are well recognized, little is known about their implications for patient selection. This paper describes an exploratory study in which the probability of undergoing an elective intervention (surgery for benign prostatic hyperplasia) in an area in the United Kingdom was compared with an area in the United States. It found that the area with high intervention rates was associated with higher levels of surgery in men with low levels of need who are unlikely to gain much benefit.