Efficiency or contractility: Which is the most informative parameter of detrusor function in women over 80 years?

Objectives: Bladder voiding efficiency (BVE) quantifies bladder emptying function and depends on detrusor contractility, which is quantified by contractility parameters (VBN parameter k and PIP1). BVE [during free flow (FF) and intubated flow (IF)], k and PIP1 are dependent on the main complaint and the urodynamic diagnosis (UD). Our purpose was to search for the most significant parameter of detrusor function in an elderly population. Patients and method: Urodynamic tracings for 98 non-neurological women over 80 years of age referred for evaluation of lower urodynamic tract symptoms (LUTS) were retrospectively analyzed. Two sub-groups were defined: A: 80–85 and B: greater than 85 years old. Data reviewed included medical history, bladder diary over three days, and current medication. Exclusion criteria were diabetes, grade equal to 2 prolapse and previous pelvic floor surgery. The urodynamic study (UDS) was interpreted according to the International Continence Society/International Urogynecological Association recommendations. The main complaints were incontinence: stress (SUI), mixed (MUI), urge (UUI); some complaints did not involve incontinence (other). Detrusor contractility was evaluated using the VBN parameters k and PIP1. Results: The populations in the sub-groups were respectively 76 and 22 women. The was a significant difference between BVE-FF and BVE-IF for MUI (P = 0.0121) UUI (P = 0.0116), and other (P = 0.0479) complaints in sub-group A and for UD in sub-group A for detrusor overactivity (P = 0.012) and detrusor underactivity (P = 0.0018), and in sub-group B for detrusor underactivity (P = 0.0177). Significant variation was observed between k and PIP1 for sub-groups A (P = 0.0013 and P = 0.0001) and B (P = 0.0026 and P = 0.0170). Conclusion: The most significant parameter of bladder function in an elderly population greater than 80 years is BVE; contractility parameter values decrease slowly with ageing.