WOMAC score and arthritis diagnosis predict decreased agricultural productivity

Abstract

Background Arthritis and joint pain are highly prevalent in agricultural (ag) workers. Many ag operations are sustained by a small number of workers, and the disability of even one worker thus contributes to economic hardship. This study investigated associations between joint health in Montana ag workers and economic well-being and work capacity. Methods This observational mixed-methods study utilized quantitative survey data and qualitative focus group data. 299 ranchers and farmers in 9 Montana counties completed either an online or paper survey that included participant demographics, joint symptoms, history of arthritis and arthritis type, financial status, work capacity, and the need to rely on others to complete one’s work. The Western Ontario and McMaster Universities arthritis index (WOMAC) survey was completed by those with hip or knee pain. Data were entered into REDCap v8.9.2 for analysis with SAS 9.4, using logistic and linear regression models to detect associations between covariables and to calculate odds ratios and confidence intervals. Focus groups were held with ranchers in two Montana counties, discussing similar topics, and the themes expressed were identified. Results 87.6% of survey respondents reported joint pain, 47.8% a diagnosis of arthritis, and 22.4% osteoarthritis (OA). A 10-point increase in WOMAC was significantly associated with lower work capacity (OR 2.00; 95% CI [1.58, 2.55], p < 0.01), worse financial condition (OR 1.23; 95% CI [1.01,1.48], p = 0.04), and increased reliance on others (OR 1.82; 95% CI [1.32, 2.55], p < 0.01). An arthritis diagnosis was associated with worsening work capacity (OR 4.66; 95% CI [2.71, 8.01], p < 0.01) and increased odds of relying on others (OR 3.23; 95% CI [1.56, 6.66], p < 0.01). A diagnosis of OA was significantly associated with decreased work capacity (OR 3.47; 95% CI [1.97, 6.11], p < 0.01). Unadjusted for age and BMI, we found a significant association between years spent working in agriculture and joint health, which became non-significant after adjusting for age and BMI. Focus group themes included decreased productivity with increased joint symptoms and a tendency for ranchers to avoid interaction with the health care system. Conclusion Poor joint health is associated with economic risk on Montana ranches and farms.

Sex-specific effects of calving season on joint health and biomarkers in Montana ranchers

“…This demonstrates a tripartite link between workload, symptoms, and OA biomarker levels. Associations between increasing WOMAC and work capacity agreed with prior findings of declining productivity with high WOMAC score and arthritis diagnosis [ 8 ].…”

“…Our study sought to determine whether calving season is an independent risk factor for the development of OA in Montana ranchers. Calving operations have been identified by ranchers as the most physically demanding season of the year and has features that may contribute to joint injury and physiologic stress [ 8 ]. Pre-season and within calving season, we assayed blood, urine and saliva samples for biomarkers known to be associated with OA and with increasing OA severity and analyzed these data with regard to predictors included in our pre-season and in-season survey.…”

“…The linkage between increased number of calvings, which relates to workload, and IL-6 may be due to the characteristics of calving season reported in a previous study, such as high levels of physical exertion, lack of sleep, cold weather, and a nutritionally poor diet [ 8 ]. These characteristics likely impact systemic inflammation and influence the profile of circulating metabolic and immune/inflammatory-signaling mediators.…”

“…For farmers, disability from OA may affect the economic health of their farm/ranch as well as the food supply. We previously found a correlation between higher WOMAC (Western Ontario and McMaster Universities Arthritis Index) pain scores and both worsening self-reported financial health of the operation and diminished self-reported ability to perform work [ 8 ].…”

“…Our focus groups with Montana cattle ranchers indicated that calving season is particularly strenuous, featuring several OA risk factors, including sleep deprivation, increased joint loads, cold weather exposure, and possibly a diet higher in convenience foods [ 8 ]. The present follow-up case–control study sought to determine whether OA biomarkers in blood and urine are elevated at the peak of calving season (“in-season”), compared to pre-season.…”