Hypothesis / aims of study
Bladder symptoms in older people are linked to adverse effects on health, safety and wellbeing. Nocturnal lower urinary tract symptoms (nLUTS) are present in up to 80% of geriatric inpatients. The causal pathway of nocturia in older patients includes frailty, multimorbidity, polypharmacy, and cognitive and gait changes (1). Currently neither attributable cost nor cost benefit from interventions for nLUTS have been measured. The aim of this study was to compare patient characteristics stratified by self-reported nocturia severity in geriatric rehabilitation inpatients to subsequently inform a model for costing nocturia during a hospital admission.
Study design, materials and methods
REStORing health of acutely unwell adulTs (RESORT) is a longitudinal, observational inception cohort assessing the physical, cognitive and physiological status by using a Comprehensive Geriatric Assessment (CGA) in geriatric rehabilitation inpatients. The study commenced mid October 2017, with patients prospectively recruited from geriatric rehabilitation wards. (HREC/17/MH/103). Patients admitted until March 2020 were included in the analyses. Written informed consent was obtained from each patient or a nominated proxy. Excluded patients were those receiving palliative care at admission, patients transferred to acute care prior to consenting to the study and patients incapable of providing informed consent without a nominated proxy.
Patients were assessed within 48 hours of admission to, and discharge from, the geriatric rehabilitation wards by physicians, nurses, physiotherapists, occupational therapists and dietitians. Nocturia was captured by item 7 of the American Urology Association Symptom Score (AUASS) and dichotomised as ≤1 void and >1 void at night as per the ICS definition (2). Differences in characteristics (comorbidity, frailty, mobility, falls history, urinary tract symptoms, and quality of life) of the subset of inpatients with and without nocturia >1 were compared using t-test or Mann-Whitney U test. An alpha level of .05 was set for the determination of statistical significance.
Results
Characteristics of the cohort are described in Table 1. Overall 641 inpatients completed item 7 of the AUASS (mean age 82.6 (SD 7.7) years, 59.9% female). Of these, nocturia occurred more than once per night in 57.4%; mean number of nocturia episodes / night was 1.96 (SD 1.38) ranging from 0-5 nocturia episodes. There was no change in nocturia severity between admission and discharge (n=0-5, mean 1.98 SD 1.35).
Table 2 shows the variables that were significantly more common in patients with clinically relevant nocturia as compared to those reporting ≤ 1 void per night: female sex, a history of falls within the last year, difficulty climbing stairs pre-admission, higher faecal incontinence score, impaired quality of life domains, lower urinary tract symptoms (urgency, frequency, incontinence) and higher levels of anxiety and depression. Delirium was significantly less common in patients with more frequent nocturia. Almost one third (31.3%) of patients with nocturia greater than once per night reported sleepiness the next day attributable to night toileting.
Age, length of sub-acute hospital stay, Body Mass Index, Mini Mental State Examination score, physical function parameters, skeletal muscle mass, Cumulative Illness Rating, Charlson Comorbidity Index, Frailty score and self-reported constipation did not differ by presence or absence of clinically relevant nocturia.
Interpretation of results
Geriatric rehabilitation inpatients with multiple episodes of nocturia experience lower quality of life, more recent falls, lower physical fitness, more current storage LUTS and faecal incontinence and poor quality sleep. Targeted assessment and intervention during rehabilitation is warranted.