Table 1

Sample characteristics (n=283)

Male (n=182)Female (n=101)Total sample
nPer centnPer centnPer cent
Age (mean, SD)38.413.039.011.538.612.4
Country of origin
 El Salvador31.700.031.1
Level of education*
 No education/don’t know84.410.993.2
 Less than high school10758.88079.218766.1
 Some high school3318.11111.04415.5
 Graduated high school3418.798.94315.2
Baseline eGFR†
 ≥90 mL/min/1.73216590.79695.026192.2
 ≥60 to <90 mL/min/1.732158.855.0217.4
 <60 mL/min/1.73210.500.010.4
 Normal weight (<25)3921.41312.95218.4
 Overweight (25–30)7440.74544.611942.0
 Obese (>30)6938.04342.611239.6
 No diabetes (HbA1c<5.7%)13979.47676.021578.2
 Prediabetes (HbA1c 5.7–6.4%)1910.91414.03312.0
 Diabetes (HbA1c≥6.5%)179.71010.0279.8
Blood pressure¶*
 Normal blood pressure (<120/80)2413.33938.66322.3
 Prehypertensive (120–139/80–89)9049.73938.612945.7
 Hypertension (≥140/90)6737.02322.89031.9
History of kidney disease
 Personal history105.544.0144.9
 Family history3217.62423.85619.8
Years in agricultural work (mean, SD)14.612.411.59.6*1411.6
Payment method*
 Piece rate5630.82019.87626.9
Farm task
 Hand pruning/weeding2413.23130.75519.4
Maximum core temperature†† (mean, SD)38.00.438.00.338.00.4
Maximum heart rate†† (mean, SD)129.628.8132.425.1130.627.6
  • *Significant at p<0.05 based on χ2 tests or t-tests comparing sexes.

  • †eGFR, based on CKD-EPI equation.

  • ‡BMI (kg/m2) categorized based on WHO classification.

  • §HbA1c from capillary blood sample.

  • ¶Blood pressure based on JNC7 categories.

  • **‘Other’ includes supervising staff, machinery repair, shoveling dirt or fumigating.

  • ††Maximum levels sustained for 3 min or longer during work shift.

  • BMI, body mass index; eGFR, estimated glomerular filtration rate; HbA1c, glycated haemoglobin.