Measures of the clinical course of AD included the age at first drink, age of onset at heavy drinking, age at onset of AD, total number of episodes, total number of diagnostic criteria met, duration of the longest episode, age at remission, and the percentage of individuals who remitted. Number of drinks was determining by asking individuals: “counting all types of alcohol combined, how many drinks did you usually have on days when you drank during the period you drank the most?” Heavy drinking was defined as: 5+ drinks in a single day, with a frequency ranging from every day to 1 to 2 times per year. To examine the progression across the landmark stages of AD (“telescoping”; Randall et al., 1999), we measured 3 time points and the intervals between them: (i) the age at first drink to age at heavy drinking; (ii) the age at heavy drinking to the age of onset of AD; and (iii) the age at first drink to the age at onset of AD.
