[1] Mayo Clin, Dept Internal Med, Div Community Internal Med, Rochester, MN 55905 USA
[2] Mayo Clin & Mayo Fdn, Mayo Med Sch, Rochester, MN 55905 USA
[3] Mayo Clin, Dept Internal Med, Div Endocrinol, Rochester, MN USA
[4] Mayo Clin, Nicotine Dependence Ctr, Rochester, MN USA
[5] Mayo Clin, Div Educ, Mayo Clin Lib, Rochester, MN USA