Table 3.

Prospective Analysis of Associations Between Arsenic Exposure and Incident Hematuria at Follow-up

As exposure variables*	n/person-years	HR (95% CI) for incident hematuria during study period
		Model 1†	Model 2‡
Baseline well As (μg/l)
0.1–3§	142/4543.60	1.00 (Ref)	1.00 (Ref)
3–25	182/5067.59	1.09 (0.88–1.36)	1.10 (0.88–1.37)
25–66	170/5223.10	0.96 (0.77–1.20)	0.96 (0.77–1.20)
66–142	184/5202.52	1.05 (0.84–1.31)	1.05 (0.84–1.31)
142–949.1	271/5692.30	1.35 (1.10–1.66)	1.34 (1.09–1.65)
HR per SD increase in exposure variable		1.10 (1.04–1.17)	1.10 (1.04–1.16)
P-value for trend		< 0.01	< 0.01
Baseline specific gravity-adjusted urinary As (μg/l)
1.7–39§	168/4994.22	1.00 (Ref)	1.00 (Ref)
39–65	181/4781.56	1.13 (0.92–1.40)	1.13 (0.92–1.40)
65–106	183/5185.17	1.01 (0.82–1.25)	1.01 (0.82–1.25)
106–179.4	186/5278.60	1.00 (0.81–1.24)	1.00 (0.81–1.24)
179.4–2334.8	230/5446.71	1.20 (0.98–1.48)	1.19 (0.97–1.46)
HR per SD increase in exposure variable		1.06 (1.01–1.12)	1.03 (0.98–1.09)
P-value for trend		0.02	0.27

^*Cut points determined by quintiles of overall study population at baseline.

^†Adjusted for age, BMI, cigarette smoking status, education length, SBP, DBP, and occupational dye exposure.

^‡Adjusted for age, BMI, cigarette smoking status, education length, SBP, DBP, occupational dye exposure, and change in urinary arsenic before incident visit.

^§Reference group.