Table 2.
Urinary tin concentration (unadjusted and creatinine adjusted) in U.S. adults in NHANES 2011–2014.
| Variable | Number | Detection rate, % |
Urinary tin concentration, µg/L
|
Urinary tin concentration, µg/g creatinine
|
||||
|---|---|---|---|---|---|---|---|---|
| Median (P25-P75) |
Geometric means (SE) |
p | Median (P25-P75) |
Geometric means (SE) |
P | |||
| Total | 3522 | 87.05 | 0.42 (0.21–0.92) | 0.49 (0.02) | 0.51 (0.28–1.02) | 0.56 (0.02) | ||
| Age | ||||||||
| 20–39 | 1261 | 82.24 | 0.36 (0.16–0.80) | 0.41 (0.02) | 0.40 (0.22–0.72) | 0.42 (0.02) | ||
| 40–59 | 1170 | 87.18 | 0.38 (0.21–0.80) | 0.45 (0.02) | <0.0001 | 0.47 (0.28–0.94) | 0.53 (0.02) | <0.0001 |
| ≥60 | 1091 | 92.48 | 0.60 (0.32–1.36) | 0.69 (0.05) | 0.79 (0.44–1.73) | 0.89 (0.06) | ||
| Gender | ||||||||
| Male | 1742 | 86.85 | 0.40 (0.21–0.83) | 0.47 (0.02) | 0.40 | 0.40 (0.22–0.73) | 0.44 (0.02) | <0.0001 |
| Female | 1780 | 87.25 | 0.43 (0.21–1.02) | 0.50 (0.03) | 0.62 (0.38–1.22) | 0.69 (0.03) | ||
| Race/ethnicity a | ||||||||
| Non-Hispanic white | 1404 | 86.61 | 0.40 (0.21–0.87) | 0.47 (0.02) | 0.52 (0.29–1.05) | 0.57 (0.03) | ||
| Hispanic | 749 | 87.58 | 0.43 (0.21–0.89) | 0.46 (0.04) | 0.03 | 0.47 (0.26–0.87) | 0.52 (0.04) | 0.39 |
| Non-Hispanic black | 803 | 91.78 | 0.71 (0.35–1.44) | 0.74 (0.05) | 0.51 (0.27–1.05) | 0.57 (0.03) | ||
| Other | 566 | 80.74 | 0.34 (0.16–0.77) | 0.39 (0.03) | 0.48 (0.28–0.87) | 0.52 (0.03) | ||
| Education b | ||||||||
| Less than high school | 792 | 89.77 | 0.50 (0.25–1.09) | 0.57 (0.04) | 0.55 (0.31–1.16) | 0.64 (0.04) | ||
| High school | 744 | 90.46 | 0.51 (0.26–1.17) | 0.58 (0.03) | 0.77 | 0.56 (0.31–1.11) | 0.62 (0.03) | 0.51 |
| College or higher | 1986 | 84.69 | 0.38 (0.18–0.81) | 0.44 (0.02) | 0.48 (0.26–0.92) | 0.52 (0.02) | ||
| Family income to poverty ratioc | ||||||||
| ≤1.30 | 1133 | 89.23 | 0.52 (0.23–1.24) | 0.58 (0.04) | 0.56 (0.31–1.18) | 0.62 (0.04) | ||
| 1.30–3.50 | 1086 | 87.57 | 0.46 (0.23–0.99) | 0.53 (0.03) | 0.049 | 0.51 (0.29–1.03) | 0.57 (0.02) | 0.03 |
| >3.50 | 1016 | 83.27 | 0.36 (0.16–0.74) | 0.40 (0.03) | 0.46 (0.26–0.84) | 0.50 (0.03) | ||
| Missing | 287 | 89.90 | 0.51 (0.26–0.99) | 0.50 (0.05) | 0.58 (0.32–1.16) | 0.62 (0.04) | ||
| Smokingd | ||||||||
| Never smoker | 2004 | 86.28 | 0.40 (0.20–0.90) | 0.46 (0.03) | 0.11 | 0.50 (0.28–0.93) | 0.54 (0.03) | |
| Current smoker | 699 | 87.27 | 0.43 (0.22–0.93) | 0.52 (0.03) | 0.53 (0.27–1.01) | 0.56 (0.03) | 0.48 | |
| Ever smoker | 819 | 88.77 | 0.46 (0.24–0.98) | 0.52 (0.03) | 0.51 (0.31–1.10) | 0.59 (0.03) | ||
| Physical activity, MET-min/weeke | ||||||||
| <600 | 1394 | 88.88 | 0.52 (0.25–1.22) | 0.59 (0.04) | 0.60 (0.34–1.30) | 0.69 (0.04) | ||
| 600–1200 | 418 | 84.93 | 0.43 (0.18–0.97) | 0.48 (0.04) | 0.03 | 0.52 (0.32–1.00) | 0.59 (0.04) | 0.02 |
| >1200 | 1710 | 86.08 | 0.37 (0.19–0.78) | 0.43 (0.02) | 0.44 (0.25–0.81) | 0.48 (0.02) | ||
| Alcohol | ||||||||
| 0 g/d | 2399 | 88.88 | 0.44 (0.22–0.99) | 0.50 (0.03) | 0.55 (0.30–1.11) | 0.59 (0.03) | ||
| 0-14g/d in women or 1-28g/d in men | 258 | 86.82 | 0.37 (0.20–0.79) | 0.44 (0.03) | 0.02 | 0.43 (0.24–0.71) | 0.46 (0.03) | 0.001 |
| ≥14g/d in women or ≥28g/d in men | 527 | 84.44 | 0.37 (0.18–0.74) | 0.43 (0.02) | 0.45 (0.25–0.82) | 0.49 (0.03) | ||
| Missing | 338 | 87.87 | 0.49 (0.25–1.03) | 0.55 (0.06) | 0.49 (0.29–1.09) | 0.59 (0.07) | ||
| BMI, kg/m2f | ||||||||
| <25 | 1110 | 84.14 | 0.35 (0.16–0.76) | 0.40 (0.02) | 0.53 (0.29–0.95) | 0.55 (0.03) | ||
| 25–29.9 | 1103 | 85.49 | 0.42 (0.21–0.93) | 0.48 (0.03) | 0.81 | 0.50 (0.29–1.04) | 0.56 (0.03) | 0.01 |
| ≥30 | 1264 | 90.66 | 0.51 (0.25–1.02) | 0.56 (0.03) | 0.48 (0.26–1.02) | 0.55 (0.03) | ||
| Missing | 45 | 95.56 | 0.79 (0.32–2.58 | 1.05 (0.35) | 1.21 (0.63–4.18) | 1.79 (0.65) | ||
All the variables were adjusted using population weights for the sample in which tin concentration was measured except N and detection rate (unweighted sample size). Analysis of variance (ANOVA) was used to compare differences of urinary concentrations of tin among various categorical variables. The lower limit of detection of the urinary tin analysis was 0.090 µg/L.
Race/ethnicity was categorized based on self-reported data into Hispanic (including Mexican and non-Mexican Hispanic), non-Hispanic white, non-Hispanic black and other race/ethnicity (Liu et al., 2017).
Self-reported education was grouped as less than high school, high school, and college or higher (Liu et al., 2017).
Family income to poverty ratios were categorized as ≤ 1.30, 1.30–3.50, and > 3.50 (Johnson et al., 2013; Liu et al., 2017).
Self-reported smoking was classified as never smokers who smoked less than 100 cigarettes in their lifetime; current smokers who currently smoke cigarettes; and ever smokers who smoked more than 100 cigarettes in their lifetime but don’t smoke currently (Liu et al., 2017).
Self-reported physical activity was used to derive metabolic equivalent of task (MET) minutes per week according to the Global Physical Activity Questionnaire Analysis Guide (WHO, n.d.-b) and categorized as <600, 600-1,200 and >1,200 MET-min/week (Liu et al., 2017).
BMI was calculated as weight in kilograms divided by the square of height in meters and classified as normal weight (BMI <25), overweight (25–29.9), and obese (≥30). Weight and height were determined by trained health technicians according to the NHANES Anthropometry Procedures Manual (WHO, n.d.-b).
BMI, body mass index; SE, standard error.