Physically demanding workloads and the risks of musculoskeletal disorders in homecare workers in the USA.

Although musculoskeletal disorders (MSDs) are prevalent among homecare workers, little is known about the MSD risk factors. This study investigated whether physically demanding workloads among homecare workers are related to MSDs, especially in neck, shoulder and back pain. Data were taken from two waves of a random sample (June to December 2003 and December 2003 to February 2004). The sample included 1643 homecare workers at Wave 1 and 1198 homecare workers at Wave 2, respectively. A basic telephone interview and 30 minutes computer-assisted interview were performed for homecare workers in Wave 1 and Wave 2. The prevalence of neck, shoulder and back MSDs was assessed at Wave 1 and Wave 2 using the Nordic questionnaire of musculoskeletal symptoms. The incidence of MSDs at 6 months was estimated at Wave 2 using only those who were in the asymptomatic reference group at Wave 1 as the denominator. At Wave 1, back MSDs were the most prevalent (10.2%), followed by neck (9.6%) and shoulder (7.1%) MSDs. After 6 months, the incidence of neck MSDs was the highest (7.0%), followed by back (6.4%) and shoulder (4.8%) MSDs. Physical demands of work were assessed using items developed from focus groups of workers. When compared with asymptomatic workers, those with MSDs showed a dose-response effect for physical job demands. After controlling for age, psychosocial demands and social support on-the-job, physical demands among homecare workers were significantly associated with an excessive odds of neck, shoulder and back MSDs incident at 6 months (odds ratios of 1.14-1.17 for each unit increase on a physical demand scale). Our study shows that the physical demands of work are a significant risk factor for MSDs among homecare workers. Considering the high physical demands among homecare workers, the finding in this study clearly indicates that practical intervention strategies should be implemented to protect homecare workers from exposure to MSD risk factors.