Arsenic exposure from drinking water and QT-interval prolongation: results from the Health Effects of Arsenic Longitudinal Study.

Background: Arsenic exposure from drinking water has been associated with heart disease; however, underlying mechanisms are uncertain.

Objective: We evaluated the association between a history of arsenic exposure from drinking water and the prolongation of heart rate-corrected QT (QTc), PR, and QRS intervals.

Method: We conducted a study of 1,715 participants enrolled at baseline from the Health Effects of Arsenic Longitudinal Study.

Tremor severity and age: a cross-sectional, population-based study of 2,524 young and midlife normal adults.

Mild action tremor occurs in most normal people. Yet this tremor mainly has been studied within the context of advanced age rather than among the vast bulk of adults who are not elderly. Whether this tremor worsens during young and middle age is unknown.