A wealth of information on drinking patterns in the Dutch population was obtained from the analysis of multiple alcohol consumption variables in a large, population-based sample of adults, ranging in age between 18 and 97 years. Frequency and quantity of alcohol use, urges to drink, and indicators of more severe alcohol use were strongly associated with each other, but less strongly with age at initiation of alcohol use, onset of regular drinking, and first alcohol intoxication. With respect to effects of sex and age, we highlight the most important findings.
Alcohol consumption was high in men and women above age 55, suggesting that the trend of increased alcohol consumption in older Dutch adults is continuing . Specifically, men and women (above age 55) drank more frequently than young adults. Excessive drinking (>14 glasses of alcohol per week) was substantially more prevalent among women above age 55 than in the young adult age group. The prevalence of excessive drinking was lowest in women between ages 25–35 years, when they typically have children , and the high proportion of excessive drinking in elderly women may be explained by their having more opportunity to drink when their children enter adulthood. Increases in alcohol consumption in older adults may be due to the growing number of healthy life years, in combination with a higher average income, which has increased substantially over the past years in the elderly Dutch population [60, 61]. Problematic alcohol use poses greater health risks for older adults than for younger individuals, since with increasing age, tolerance to the effects of alcohol declines. In addition, older adults may use medication that interacts negatively with alcohol, or suffer from chronic physical or psychological illness, such as diabetes or mood problems, that may be worsened by alcohol [22, 62].
Recent data suggest that the gap between male and female drinking is narrowing among young adults [13, 63, 64]. This trend is corroborated by the finding that among participants between 18–25 years old, women initiated alcohol use, started drinking regularly, and reported first alcohol intoxication at the same ages as men. Declining sex differences are mainly caused by increases in alcohol use in women, which may result from women having more freedom and financial independence. Drinking among women has also become more socially accepted than several decades ago, and young women nowadays may have fewer family responsibilities . This trend has important consequences for public health, since women are more susceptible to the harmful effects of alcohol, such as liver and heart disease, than men .
Additionally, since the 1940s-50s, when the individuals in the highest age category were adolescents, alcohol initiation, onset of regular drinking, and first intoxication have been occurring at increasingly younger ages. This is in line with the increase in alcohol consumption in the Dutch population observed between 1950 and 1980, specifically of beer and imported wine [67, 68]. The increase was likely due to strong economic growth and increases in international commerce during this period . It should be noted, however, that the differences in age at alcohol initiation between young and old participants may be slightly overestimated due to retrospective reporting bias [70, 71].
Besides age and sex, initiation of cigarette and cannabis use were the most striking risk factors for increased alcohol use, early alcohol initiation and age at first alcohol intoxication. These associations are likely explained by an underlying genetic vulnerability for substance use . Individuals who use multiple substances often meet more criteria for abuse or dependence than those who only use a single substance. Moreover, using more than one substance is associated with increased health risks, due to the combined harmful effects of alcohol and cigarettes or cannabis [73, 74].
Some limitations of this study should be noted. Self-report data may be imprecise due to memory errors or underreporting of substance use . Moreover, 50% of the sample were twins. Twins are born in all population groups, which makes having a twin in the family a suitable criterion for families to be included in a population-based sample . Nevertheless, twin studies have been criticized since pregnancy and birth of twins carry increased risks and twins generally have a lower birth weight than singletons . These are risk factors for behavioral problems, which are strongly related to alcohol use [78, 79]. However, studies in several European countries have not observed differences in externalizing problems between twins and singletons during childhood and adolescence [80, 81].
The participants in the 65+ age group ranged in age between 65 and 97 years. As age increases, so does the risk of cognitive impairment, which may have lead to imprecise reports of alcohol use . Moreover, although the cutoff for hazardous drinking based on the AUDIT questionnaire was lowered for the older participants, it may not be appropriate for this entire age range, since with increasing age, the ability to metabolize alcohol decreases [22, 62]. Similarly, the CAGE questionnaire was developed in a sample of males under age 61 , and may therefore not be entirely appropriate for the oldest participants.
Excessive alcohol use was based on number of glasses consumed per week, and thus may have been somewhat inaccurate, since the criteria for excessive alcohol use are based on standard glasses of alcohol , which were not specifically reported in the survey.
Because of the large number of predictor variables, no other interaction effects were examined than between age and sex, while these may be relevant in the prediction of alcohol consumption. For example, those above age 55 years who seek treatment for alcohol use disorders are more often highly educated than treatment seekers below age 55 years . Similarly, alcohol dependence is positively related to high education in women, but not in men .
To summarize, we observed that elderly Dutch men and women continued to drink alcohol more frequently than young adults, and excessive drinking was substantially more prevalent in elderly women than in young adult women. Until now, alcohol prevention campaigns have predominantly targeted adolescents and young adults, but the high levels of alcohol consumption among older adults warrant prevention and intervention campaigns aimed specifically at this age group . Initiation of alcohol use, onset of regular drinking, and first alcohol intoxication occur at increasingly younger ages, and the gap that previously existed between men and women in age at alcohol initiation, age at onset of regular drinking, and age at first alcohol intoxication continues to close.