Are Physical Activity and Cognitive Function Impacted by Hearing Loss in Aging Farmers in Rural Nebraska, U.S.?

Independent farmers who operate their own crop production were recruited through agricultural fairs. As part of a larger project investigating HL in farmers and ranchers, a total of 98 agricultural workers have had their hearing tested. Eleven of them participated in the balance testing prior to the spring planting season. Farmers also completed a background survey of noise and chemical exposures, and the Montreal Cognitive Assessment (MOCA) to identify the risk for cognitive impairment. The Speech Intelligibility Index was used as a high frequency pure tone average (HF PTA) as a summative measure of hearing sensitivity. Farmers were then fitted with a small remote sensor on their belt above their hip to record their body movement during daily activities for a week. Farmers recorded their daily activities on a log form, performed the Timed-Up-and-Go (TUG) test 4 times per day to assess their physical health and balance, and took a short walk on a solid surface (sidewalk or street) each day. Physical activity was coded using Python for active time periods (e.g., walking, standing) and sedentary activity (e.g., sitting). An overall activity score was computed for each farmer. A higher score represents more physical activities. Correlation analysis was applied for all outcomes among physical health, cognitive function, and HL.

Among 11 farmers (two female; aged 60-69), the average activity score was 724.82 (ranged 204-1533). The average TUG score was 8.81sec (ranged 6.73 - 12.43sec). Farmers presented with sensorineural HLconsistent with noise exposure, the average of the HF PTA was 52 dB HL (ranged 27-82 dB HL) in their worse ear. A moderate correlation (R=0.47) was observed between severity of HL and their maximum activity score over 7 days. All participants passed their cognitive screen on the MoCA (average score was 28.17).

Our preliminary data suggested farmers with more severe levels of HL recorded less standing and walking activity during the planting session. HL and associated loss of social communication along with other health risks may contribute to dementia risk in this population.  Further research is needed in this area.

Work-related noise exposure in aging farmers impairs hearing and cognitive functions. While performing physical examination with those aging farmers, physical therapists should consider working with other health professions, such as speech language pathologists and occupational therapists, to evaluate hearing sensitivity, cognitive function, and work-related exposures. It is critical to have an interprofessional team to assess the multifactorial impact on physical health in aging farmers.