RT Journal Article SR Electronic T1 Workload and cross-harvest kidney injury in a Nicaraguan sugarcane worker cohort JF Occupational and Environmental Medicine JO Occup Environ Med FD BMJ Publishing Group Ltd SP 818 OP 826 DO 10.1136/oemed-2019-105986 VO 76 IS 11 A1 Hansson, Erik A1 Glaser, Jason A1 Weiss, Ilana A1 Ekström, Ulf A1 Apelqvist, Jenny A1 Hogstedt, Christer A1 Peraza, Sandra A1 Lucas, Rebekah A1 Jakobsson, Kristina A1 Wesseling, Catharina A1 Wegman, David H YR 2019 UL http://oem.bmj.com/content/76/11/818.abstract AB Objectives To examine the association between workload and kidney injury in a fieldworker cohort with different levels of physically demanding work over a sugarcane harvest, and to assess whether the existing heat prevention efforts at a leading occupational safety and health programme are sufficient to mitigate kidney injury.Methods Biological and questionnaire data were collected before (n=545) and at the end (n=427) of harvest among field support staff (low workload), drip irrigation workers (moderate), seed cutters (high) and burned sugarcane cutters (very high). Dropouts were contacted (87%) and reported the reason for leaving work. Cross-harvest incident kidney injury (IKI) was defined as serum creatinine increase ≥0.30 mg/dL or ≥1.5 times the baseline value, or among dropouts reporting kidney injury leading to leaving work.Results Mean cross-harvest estimated glomerular filtration rate change was significantly associated with workload, increasing from 0 mL/min/1.73 m2 in the low-moderate category to −5 mL/min/1.73 m2 in the high and −9 mL/min/1.73 m2 in the very high workload group. A similar pattern occurred with IKI, where low-moderate workload had 2% compared with 27% in the very high workload category. A healthy worker selection effect was detected, with 32% of dropouts reporting kidney injury. Fever and C reactive protein elevation were associated with kidney injury.Conclusions Workers considered to have the highest workload had more cross-harvest kidney damage than workers with less workload. Work practices preventing heat stress should be strengthened and their role in preventing kidney damage examined further. Future occupational studies on chronic kidney disease of unknown aetiology should account for a healthy worker effect by pursuing those lost to follow-up.