Reasons for changing caffeinated coffee consumption: the Rancho Bernardo Study.

OBJECTIVE: To determine patterns of lifetime caffeinated and decaffeinated coffee use, focusing on frequency and determinants for curtailing caffeinated coffee.
METHODS: Residents of Rancho Bernardo, a white, upper-middle class Southern California community, were surveyed about their lifetime coffee-drinking behavior; completed questionnaires were received from 69% (n = 2955; mean age was 64 years, age range: 30-105 years). Chi-square tests of differences between proportions in categorical data and t-tests for continuous data were used. Due to the large number of comparisons, statistical significance was defined as p<or=0.01.
RESULTS: Respondents began drinking caffeinated coffee around age 20, and decaffeinated coffee around age 50. A few gender-related differences were observed; more women than men curtailed caffeinated coffee (p<0.001), or did so due to sleep problems (p<0.01), while more men curtailed coffee because their spouses stopped drinking it (p<0.001). Most who curtailed caffeinated coffee did so on their own initiative (80% for health concerns); but only 10% of coffee drinkers curtailed caffeinated coffee on advice of a physician. Past combined intake of caffeinated and decaffeinated coffees approached >or=5 cups/day only in those who curtailed caffeinated coffee on advice of a physician or for heart/circulatory problems.
CONCLUSIONS: Curtailing of caffeinated coffee in this adult cohort was primarily due to health concerns, but few of those who curtailed caffeinated coffee attribute the change to the advice of a physician.