[1] Univ Pittsburgh, Sch Publ Hlth, Dept Environm & Occupat Hlth, Pittsburgh, PA USA
[2] Univ Pittsburgh, Dept Med, Renal Electrolyte Div, Pittsburgh, PA USA
[3] Brown Univ, Warren Alpert Med Sch, Div Kidney Dis & Hypertens, Providence, RI USA
[4] Brown Univ, Rhode Isl Hosp, Warren Alpert Med Sch, Div Kidney Dis & Hypertens,Dept Med, 375 Wampanoag Trail, East Providence, RI 02915 USA