Treating vascular risk factors and maintaining vascular health: is this the way towards successful cognitive ageing and preventing cognitive decline?

Dementia is a progressive disorder that typically worsens with time and from which recovery is unlikely. The incidence of dementia increases exponentially with ageing and is an important public health challenge. There is now growing evidence for the role of vascular factors in Alzheimer's disease, mixed dementia (Alzheimer's disease with cerebrovascular disease), and of course vascular dementia. With the rising prevalence of vascular disease, there are increasing numbers of people who are identified to be at risk of cognitive impairment. By changing modifiable vascular risk factors, there is emerging evidence that it may be possible to prevent or delay the expression and progression of dementia.

Sexual selection. Are ducks impressed by drakes' display?

Surprisingly few birds have penises, but among those that do, the Argentine lake duck (Oxyura vittata) tops the bill - the penis of this small stifftail duck from South America is shaped like a corkscrew and, at almost half a metre long, is the largest of any bird measured so far. Factors responsible for the evolution of this remarkable organ could include runaway selection, whereby drakes with longer penises gain dominance and copulate with more females, or preference by females for drakes with longer and more decorated penises.

Propentofylline treatment for Alzheimer disease and vascular dementia: an economic evaluation based on functional abilities.

A Canadian economic evaluation of propentofylline (a therapy shown to be effective for patients with mild to moderate Alzheimer disease and/or vascular dementia) versus standard care was conducted. Patients were categorized by functional abilities according to the Alberta Resident Classification System by translating measures that were originally captured through the Gottfries-Bråne-Steen scale. The Alberta Resident Classification System was then linked to a community dataset of home care costs for a population with dementia. Cost and cost-effectiveness analyses were performed from the perspective of the Ministry of Health, the caregiver, and society using an intent-to-treat analysis for propentofylline versus placebo. Results, limited to the 48-week clinical trial duration, indicated that propentofylline improved health outcomes of persons with dementia as statistically significant treatment effects were found. However, although an incremental cost for the propentofylline intervention was incurred from the Ministry of Health perspective, home care and, to a larger extent, caregiver costs were reduced. Savings in these areas may have partially offset annual treatment medication costs because a non-statistically significant cost difference was observed from a societal perspective.

Aging-related clinical and health services research in Canada.

Research by Canadian geriatricians has grown significantly since the Canadian Society of Geriatric Medicine was founded in 1981. Most research has been clinical or related to health service use. More recently, the Canadian Study of Health and Aging (CSHA) has proved an important focus for population-based research, and research on dementia. An increasing number of Canadian geriatricians have undertaken formal research training, and the CSHA study team and other groups are providing opportunities for multicentre, multidisciplinary, collaborative studies. These developments point to continued growth in research by Canadian geriatricians, most likely research with a clinical and population focus and employing multicenter designs.

Variability of post-void residual urine volume in the elderly.

Residual urine volume, though clinically important as a diagnostic tool, is reported to be variable and unreliable. Variability was examined among 14 geriatric patients, mean age 77 years. Residual urine was measured by ultrasound at three different times of day on each of two visits separated by 2-4 weeks. Results were examined by analysis of variance. Mean residual urine was 154 ml. Between-patient variability was large [standard deviation (SD) 246 ml]. There was no significant difference between values in men and women, nor between visits. Within-patient variability was large because of a large systematic variation with time of day (SD 128 ml), with greatest volumes in the early morning. The inherent, random variability of the measurement was much smaller than this (SD 44 ml). If the physiological factors causing the temporal variation could be controlled, more reproducible measurements would be possible.

Urge incontinence in elderly people: factors predicting the severity of urine loss before and after pharmacological treatment.

Geriatric patients with urge incontinence lose different amounts of urine and respond differently to treatment. Identification of factors predicting the amount of urine loss before or after treatment might help to select therapy. We have sought such factors in 41 elderly patients (23 women and 18 men), mean age 79 years with established urge incontinence that was urodynamically proven to be associated with detrusor hyperreflexia, who were treated with oxybutynin chloride. Urine loss was measured by 24-hour monitoring (mean 378 g/24 hour). Demographic, psychosocial, behavioral, cortical, circulatory, urodynamic, and urological factors were studied before and after treatment. Multiple regression analysis showed that, before intervention, factors predicting the amount of urine loss were fluid intake, voiding frequency, and impaired orientation on cognitive testing. After intervention, urine loss was significantly smaller (mean 259 g/24 hour). Different factors predicted the amount of this persistent incontinence: underperfusion of the cerebral cortex, reduced bladder sensation, and (again) impaired orientation. The analysis confirms that the severity of geriatric urge incontinence associated with detrusor hyperreflexia, particularly incontinence that is resistant to anticholinergic therapy, depends on cortical factors, that bladder sensation plays an important role, and that therapeutic manipulation of fluid intake and voiding frequency may offer a modest reduction in urine loss (e.g., about 40 g/day).

Cerebral aetiology of urinary urge incontinence in elderly people.

We have examined 73 elderly incontinent patients (mean age 79 years) and 27 continent subjects (mean age 78 years) of similar cognitive status. Among the incontinent patients, 20 were shown objectively to have urge incontinence with normal bladder filling sensation, 14 had objectively demonstrated urge incontinence with reduced bladder sensation, and 39 had other types of incontinence. We compared cognitive function (by Mini-mental State Examination: MMSE) and regional brain perfusion (by SPECT scanning) in these four groups. Patients with objectively demonstrated urge incontinence and reduced bladder sensation stood out as being different from the rest: their mean MMSE score was significantly lower than that of any of the other three groups; perfusion of the frontal cortex was significantly poorer than that in the continent and other incontinent groups; global cortical perfusion was significantly poorer than in the other incontinence groups. This was not found in patients with urge incontinence and normal bladder sensation. The observations support the hypothesis that in elderly people urge incontinence with reduced bladder sensation can be a consequence of cortical neuropathy, especially in the frontal lobes.

Long-term changes in urodynamic studies of voiding in the elderly.

Urodynamic studies were conducted in 80 incontinent elderly patients (27 men and 53 women; mean age, 77 years) and repeated 2-4 weeks later after patients had been subject to interventions. Interpretable voiding studies were performed in 84% of sessions. Interpretable initial and repeat studies were performed in 74% of patients. For detrusor pressure at maximum flow the intra-individual, between-sessions variability was +/- 11.7 cm H2O (SD) and the initial-repeat correlation coefficient was 0.61. For maximum flow rate the corresponding figures were +/- 4.7 ml/s and 0.44. Mean residual urine volume was 195 ml, with a between-sessions variability of +/- 113 ml (SD). These results suggest that there is substantial long-term variability in voiding function, including urethral resistance. Of the mean, 5% showed a change in obstruction classification (unobstructed/obstructed) between sessions. This variability and the modest proportion of interpretable studies should be taken into account when assessing urethral obstruction and designing clinical trials.

Urinary incontinence in the elderly: the brain factor.

Recent research has shown that urge incontinence is common in the elderly and is often combined with reduced bladder sensation. It is associated with cognitive impairment and with underperfusion of the frontal lobes of the cortex. To test for an expected preferential association with particular aspects of cognitive function, 47 incontinent patients (25 men and 22 women, median age 78 y) underwent cognitive testing, 24-hour monitoring of bladder function and videourodynamics. Median CAMCOG score was 72/107. Median urine loss in 24 h was 36 g (range 11-1347 g). 17 patients had urodynamic proof of urge incontinence, 8 with normal and 9 with reduced bladder sensation. Impaired orientation in time was more strongly associated with proven urge incontinence than overall cognitive impairment; it was the only significant predictor (P < 0.00005). Praxis, calculation ability, abstract thinking or recent memory were less closely involved. Thus dysfunction of the frontal cortical lobes and impairment of temporal orientation appear to constitute a "brain factor" underlying geriatric urge incontinence, particularly in combination with reduced bladder sensation.

Polypharmacy and its effect on urinary incontinence in a geriatric population.

The relationship between medication and incontinence was studied retrospectively in 128 elderly patients enrolled in an incontinence study. Patients were taking up to 18 non-topical medications but most of these were unlikely to have a significant urological effect. Nevertheless, 62% of patients were receiving, for other medical problems, up to 4 drugs which could potentially affect the lower urinary tract. These were classified by their mode of action. The most common types of urologically active medication, apart from diuretics, were calcium channel blockers, used by 21% of patients, and tricyclic antidepressants, used by 12%. The urodynamic findings in patients on different types of medication were compared. Patients with urodynamically proven urge incontinence who were on calcium channel blockers had significantly less urine loss than those not on the drug. Tricyclic antidepressants have been used in the treatment of urge incontinence; in this study urine loss was less severe among those receiving tricyclics, although the differences were not significant. A few patients on beta-blockers apparently had more severe urge incontinence. Drugs prescribed to the elderly for non-urological medical problems can affect the lower urinary tract and may have some effect, either beneficial or adverse, on incontinence.

Relationship of fluid intake to voluntary micturition and urinary incontinence in geriatric patients.

The aim of this study was to investigate, in a group of geriatric inpatients with established incontinence, the relationships among urine loss, voided volumes, frequency of voiding, and fluid intake. The investigated included 128 patients: 76 women and 52 men, with a median age of 79 years. One-half had significant cognitive impairment. Patients underwent 24-hr monitoring of fluid intake, urine loss, and voiding, as well as conventional videourodynamic testing. Diurnal and nocturnal voiding frequencies were significantly but relatively weakly related to fluid intake. Diurnal and nocturnal voided volumes were more closely related, however, to the fluid intake. There was a strong and easily interpretable relationship among nocturnal voided volume, nocturia, cystometric bladder capacity, and evening fluid intake. Sixty of 128 patients had urodynamically proven urge incontinence, and this group was studied separately. They were more cognitively impaired and had significantly greater urine loss and smaller fluid intake than was true of the other incontinent patients. Urine loss was significantly related to fluid intake in this group. Nocturnal urine loss increased by an average of 28 ml/dl of evening fluid intake and decreased by 17 ml/dl voided at night. These results suggest that nocturnal toileting and evening fluid restriction may reduce nocturnal urine loss by a small but useful amount in carefully selected older patients with severe urge incontinence.

Effect of transurethral resection of the prostate on detrusor instability and urge incontinence in elderly males.

Detrusor instability is common in men with evidence of outflow obstruction due to benign prostatic hypertrophy and typically reverses in about two thirds of patients after transurethral resection of the prostate (TURP). It is also common among the elderly without outflow obstruction and may lead to urge incontinence. To determine whether TURP has an effect on detrusor instability and urge incontinence in elderly men, or whether these abnormalities are due to other age-associated changes, 12 males (mean age 80 years) with urge incontinence or frequency and urgency of micturition, and symptomatic benign prostatic hypertrophy, were studied by 24-hour monitoring of incontinence and videourodynamic examination, before and after TURP; 7/12 patients were significantly cognitively impaired. Preoperatively, all patients showed detrusor instability, which reversed postoperatively in only one patient, a significantly smaller proportion than that consistently reported in younger patients. Preoperatively, 11/12 patients were incontinent. After TURP, 8/11 patients had an improvement in the amount of incontinence, by up to 458 g in 24 hours. Those who improved had been urodynamically more severely obstructed preoperatively. Those with the most improvement were also cognitively impaired. We conclude that, in the geriatric population, detrusor instability and urge incontinence may be the result of age-associated changes and not secondary to obstruction. Detrusor instability is likely to persist following TURP. Preoperative urodynamic assessment of obstruction in the incontinent male with benign prostatic hypertrophy may be useful since the severity of incontinence responds well to TURP if there is marked obstruction. Cognitive impairment should not be a deterrent to operation.

Characteristics of urinary incontinence in elderly patients studied by 24-hour monitoring and urodynamic testing.

Characteristics of urinary incontinence have been studied in 100 elderly incontinent patients using invasive video-urodynamics and noninvasive 24-h monitoring of incontinence, fluid intake, voiding and residual urine. Incontinence was of the urge type in 51 patients, including 24 with reduced bladder sensation. Noninvasive 24-h monitoring showed satisfactory reproducibility and high sensitivity (88%) for detecting urine loss. Urodynamically proven urge incontinence, especially in combination with reduced sensation, and recent bacteriuria were associated with severe urine loss on 24-h monitoring. On 24-h monitoring, urine output was significantly larger at night and nocturia was common. In urge incontinence urine loss was predominantly nocturnal and the amount depended significantly on the previous evening's fluid intake and on nocturia. Noninvasive 24-h monitoring showed that post-void residual was common and was often largest in the early morning. It also yielded many free-voiding flow curves. Normal flow curves with small residual urine make dysfunction of voiding itself unlikely. Thus noninvasive monitoring provides information about incontinence and voiding that is suitable for designing intervention and management strategies. Invasive testing may be necessary however to confirm the urodynamic type of incontinence or suspected voiding dysfunction.

Incontinence in the elderly: objective demonstration and quantitative assessment.

Subjective and objective methods of demonstrating incontinence and assessing its severity have been compared in a group of elderly patients with a high incidence of severe urge incontinence. It was found that 24-h in-patient monitoring of urine leakage was the most sensitive method of demonstrating incontinence, with videourodynamic testing almost as good. In comparison, a 1-h pad test was poor. Visual inspection during physical examination seldom demonstrated leakage. For quantitative assessment of severity, 24-h monitoring gave the most reproducible results; it was also able to reveal significant changes in severity in response to pharmaceutical treatment. A 1-h pad test was less reproducible and suggested changes that were only poorly consistent with 24-h monitoring. The subjective responses of the patients were not useful in assessing changes in the severity of incontinence. Twenty-four hour monitoring thus stands out as a superior method of demonstrating and assessing incontinence.

Our underpinnings: a bicentennial view. The 1975 Harvey Cushing oration.

The author describes the emergence of the liberal traditions which is the foundation of the political and economic systems in this country and considers policies that may affect our social and economic future.