Prevalence and Risk Factors of Musculoskeletal Disorders among Solid Waste Collectors employed by the Local Administrative Organizations at Nong Bua Lam Phu Province

Abstract

This cross-sectional analytic study aimed to investigate the prevalence of musculoskeletal disorders
(MSDs) and risk factors related to MSDs among solid waste collectors at the Nong Bua Lam Phu Province.
Altogether 160 workers participated in this study. Data were collected by using a structured questionnaire and
by investigating the work environment. Descriptive statistics were used to describe the demographic
characteristics of the workers, the working environment and the prevalence of MSDs. For inferential statistics
the Chi-square test, with the Fisher exact test and multiple logistic regression analysis with 95% confidence
interval (95% CI) of the odds ratio (OR) were used to identify risk factors of MSDs.
The prevalence of MSDs as asked for the last 7 days and the last 12 month were 73.75% (95% CI =
66.21 – 80.38) and 90.00% (95% CI = 84.26 – 94.17). The highest prevalence of MSDs was found at the lower
back (77.50%), followed by upper arms (58.75%) and shoulders (56.88%). The most severity disorders were
reported from the above mentioned three locations namely lower back, upper back and shoulder. Risk factors
which were found significantly associated with MSDs were age ≥ 40 years (OR = 3.64, 95% CI = 1.17 – 11.22),
work experience ≥ 4 years (OR = 6.42, 95% CI = 1.86 – 21.87), smoking every day (OR = 5.29, 95% CI = 1.41 –
8.18), work for 7 days per week (OR = 5.14, 95% CI = 1.10 – 47.91), hanging on the site of the waste collecting
vehicle (OR = 3.71, 95% CI = 1.13 – 12.53), no breaks during work (OR = 3.03, 95% CI =1.07 - 8.52) and a BMI
of ≥ 25 kg/m2 (p = 0.024). From the multivariate analysis, age ≥ 40 years (adjOR = 5.35, 95% CI = 1.09 – 26.19),
work experience ≥ 4 years (adjOR = 4.95, 95% CI =1.02 – 23.94), smoking every day (adjOR = 7.27, 95% CI =
1.14 – 46.27), no breaks during work (adjOR = 7.05, 95% CI = 1.48 – 33.42) and work for 7 days per week
adjOR = 5.80, 95% CI = 1.02 – 32.86) were significantly associated with MSDs.
Therefore, the high prevalence of MSDs, particularly for low back pain is an important finding affecting
the health of solid waste collectors. Personal and work related risk factors of MSDs identified in this study were
very useful for health promotion and the occupational diseases surveillance program which should be further
conducted for solid waste collectors for the prevention of MSDs.
Keyword: musculoskeletal disorders, solid waste collectors, prevalence