Nocturia: impact on quality of life in a Dutch adult population.

OBJECTIVE: To estimate the effect of nocturia on quality of life (QoL) and to assess the associated effects of sleep problems. SUBJECTS AND METHODS: From a random sample of Dutch adults (>/= 18 years old) 1000 were selected after stratification to complete a written questionnaire. Respondents (819) were distributed over three groups: a target group (189, who felt bothered by >/= one void/night); a reference group 1 (120 reporting >/= two voids/night but with no bother); and reference group 2 (510, with 0-1 voids/night). Nocturia, other lower urinary tract symptoms and perceived impact on life were measured using the Bristol Lower Urinary Tract Symptoms Questionnaire (B-LUTS). Sleep problems were measured using the Sleep Wake Experience List (SWEL) and QoL using two subscales from the RAND-36, i.e. 'physical functioning' and 'mental health'. RESULTS: The perceived impact on life was highest in the target group (P < 0.05), which also had more sleep problems and scored lower on the QoL scores than both reference groups (P < 0.05). Statistically significant differences in mental health and physical functioning between the target and reference groups became insignificant after correcting for sleep problems, indicating that the effect of nocturia (with bother) is mediated by sleep problems. CONCLUSIONS: Nocturia may lead to sleep insufficiency and consequently to a decrease in mental and physical health. Patients who consult a doctor for nocturia should thus be treated adequately. In addition, it is worthwhile for doctors to routinely check if patients who contact them for sleep problems also have nocturia.

Mechanical loading on the low back in three methods of refuse collecting.

The mechanical loading on the low back was studied in three different current methods of refuse collecting: in polythene bags, two-wheeled mini-containers and large four-wheeled containers. To this end the most prominent activities of each collecting method were performed in a laboratory. On the basis of movement analysis, force measurements and biomechanical modelling, spinal compressive and shear forces were estimated. From these forces and from the frequency of activities during the working day (assessed in a preliminary field study) the low-back stress in each collecting method was evaluated. In the bag-method, peak forces when throwing the bags ranged from 3341 to 5179 N (average compression) and from 284 to 673 N (shear) among the different conditions studied. The act of picking up bags also showed rather high forces (exceeding the NIOSH limit for disc compression in most cases). The frequency of exposure to these forces in the field is rather high (workers pick up and throw on average 807 times each day). The mini-container method compares favourably to the bags method. Peak compressive and shear force in tilting/pushing and pulling mini-containers ranged from 1657 to 2654 N and from 123 to 248 N respectively. Also, the frequency of stressful events in the field is lower in this method. In the large container method extremely high peak forces (e.g. compression ranged from 4991 to 5810 N) were observed in the task of putting the empty container back from street level to sidewalk level (surmounting the kerb). The frequency of activities like pushing, pulling and lifting the large container in the field is much lower compared with activities in the other methods. On the basis of the frequency and magnitude of spinal forces it was concluded that the mini-containers should be preferred to the bags. If kerbs are removed at container places and tasks are performed by two instead of a single person, the large container method would form another good alternative to the stressful task of collecting refuse in bags.