Risk factors for sick leave due to musculoskeletal disorders among self-employed Dutch farmers: a case-control study

BACKGROUND: In Dutch agriculture, musculoskeletal disorders are a main cause of sick leave. Among self-employed insured farmers, neck, shoulder, upper extremity, and back disorders accounted for 30% of the claims for sick leave of less than 1 year This case-control study set out to identify and quantify risk factors for sick leave due to musculoskeletal disorders among self-employed Dutch farmers. METHODS: Sick leave, claimed at an insurance company from 1998 to 2001 for back (SL-BP, n = 198) or neck/shoulder/upper extremity trouble (SL-EXT, n = 89) was analyzed; the controls did not file any claim in this period (n = 816). RESULTS: Multivariate analysis showed that risk factors for SL-BP were increased age (OR = 1.06 per year, CI = 1.04-1.09), body mass index (BMI) >27 (OR = 1.93, CI = 1.2-3.2), smoking (OR = 1.90, CI = 1.2-2.9), former pain (OR = 3.28, CI = 2.1-5.1), tractor driving >1,000 hr/year (OR = 2.44, CI = 1.0-6.4), and "high work pace and workload" (OR = 1.59, CI = 1.0-2.4). SL-EXT was associated with pig (OR = 3.63, CI = 1.4-9.7), mushroom (OR = 6.14, CI = 1.4-27.2), or dairy/pig farming (OR = 4.56, 1.1-19.5), while age (OR = 1.10, CI = 1.06-1.14), smoking (OR = 1.79, CI = 1.0-3.2), and former pain (OR = 3.37, CI = 1.9-6.1) were also contributing. CONCLUSIONS: Prevention of sick leave of self-employed farmers should focus on life style (obesity, smoking), reducing older farmers' exposure to physical load, exposure to long-term tractor driving. Specific attention should be paid to animal and mushroom farmers.