Lower drinking age linked to higher longterm harm

American researchers investigating the longterm impacts of a lower legal drinking age in some US states say the evidence points to higher risk of serious harm including suicide and homicide, when the drinking age is lower.  

Photo: BytemarksTheir study — released online in the journal Alcoholism: Clinical & Experimental Research — looked at data gathered before 1984, when a blanket legal drinking age of 21 was applied across the US.  Registered journalists can log into the SMC Resource Library to access the research.

It showed that a higher risk of suicide and homicide persisted into adulthood among women born after 1960 who came from states that permitted under-21 drinking.

“Alcohol results in suicide attempts being more lethal, so we suspect that long-term alcohol problems may lead to more frequently lethal suicide attempts among women.” said lead author Professor Gruzca, from Washington University School of Medicine in St. Louis.  Women had a 12 percent higher risk of suicide and a 15 percent higher risk of homicide if they grew up where drinking was permitted at younger ages, making a new argument for keeping the legal minimum drinking age at 21, the researchers said.

“Grucza and colleagues have elegantly demostrated that individuals who were young adults during a time in which they could legally drink between the ages of 18 and 21 have far-reaching health consequences into adulthood,” Katherine M. Keyes, a postdoctoral fellow in epidemiology at Columbia University who was not involved in the study, said in a statement released by the journal.

The researchers looked at both men and women, but said increased levels of suicide and death through homicide “may relate to unique alcohol-related risks faced by women”. Suicide attempts are more common in women, and attempts under the influence of alcohol are more lethal.  Two-thirds of intimate-partner-violence homicides in the USA are perpetrated against women:  one in three murdered women are killed by a current or former partner, while this segment of male murder victims is just one-in-20.

In New Zealand, the Law Commission last year urged the Government to raise the drinking age to 20, and the  Alcohol Reform Bill now before Parliament introduces a new purchase age regime: 18 for on-licences, and 20 for off-licences. “The provisions will ultimately likely be subject to a conscience vote in Parliament,” Justice Minister Simon Power said during the Bill’s second reading..

The SMC gathered the following comments from New Zealand experts.   Contact the SMC for further details.

Dr. Joe Boden, a Senior Research Fellow working on the Christchurch Health and Development Study, commented before seeing the full report:

“US state laws generally set a legal ‘drinking age’, where New Zealand had a legal age of purchase.

What this means is that in the US it is illegal for underage individuals to be in possession of and consume alcohol … here it is not. The change in drinking ages in US states occurred over a period of time leading to a non-uniform pattern of laws at various points. There were states with different drinking ages at the same time, but to examine these issues using NZ data, we would have to compare rates pre-1998 with rates post-1998, which is problematic in some respects.  Still, it’s likely not impossible.”

Professor Jennie Connor, Head of Preventive and Social Medicine, Dunedin School of Medicine commented on the report:

“This study adds considerable weight to the evidence of long term harm from lower legal drinking/purchase ages.There is evidence from the US and from elsewhere that a lower drinking age or legal alcohol purchase age is associated with increased heavy drinking among young people and resulting harm  – and this has been most measured often for motor vehicle crash injuries, suicide and homicide (in the US). Evidence about the increased harm from traffic injury in the US contributed to the reinstatement of a uniform drinking age of 21 years by 1984. This had occurred well before NZ decided to lower the purchase age despite the existing evidence that it would be harmful.

“Heavy drinking in adolescence has been linked to poorer outcomes in later life, not only problems from alcohol use but those resulting from lost opportunities.What this new research suggests is that harmful effects of a lower drinking age are still felt into middle age, particularly by women. In this study women who lived in places where there was a lower drinking age when they were young had higher suicide and homicide risks than others.

“This is not very surprising since it is well established that alcohol escalates the severity  of violence and may contribute to completion of suicide. Recent research has documented the involvement of alcohol in partner aggression in a sample of the general population. NZ has a high prevalence of heavy drinking among young people, and the volumes of alcohol that young people drink on each occasion have increased with the liberalisation of alcohol controls. With the lowering of MLPA (minimum legal age to purchase alcohol) in 1999 and the rise of RTDs (ready-to-drink) there has been a drift down in the de facto drinking age.

“What this research is telling us is that as well as all of the direct harms to young people from early heavy drinking: injury, violence, poisoning, trouble with police, lost educational opportunities, social and family disruption, risky sexual behaviour and so on, there are consequences that are persistent and that we are not fully aware of. Not only that, this research tells us that when you restore the drinking age to 21 these consequences start to reduce.

“There is no health or welfare argument for having a low legal purchase age in New Zealand. The argument that young people’s drinking is harmless and they grow out of it is  untenable. There is evidence that the harmful effects on the population of having a low purchase age are reversed when the age is raised. The clear message is that returning  the MLPA to 20 would have  benefits for health and wellbeing of young NZers that they will carry through their lives. The barriers to doing this are largely commercial and would put the needs of local and transnational businesses ahead of those of NZ communities.

“Raising the purchase will not on its own make a very rapid or substantial impact on the culture of heavy drinking in NZ, as most of the drinking involves older people. The key  measures required to reduce heavy drinking effectively are substantially increasing the price of alcohol, restricting availability (places and times of sale), eliminating promotion and marketing, and lowering the adult BAC (blood alcohol content limit currently at  0.08%)  to 0.05%. In terms of doing similar research in NZ there has been an evaluation of the lowering of the MLPA on young driver road  traffic crashes that indicates harm (Kypri et al). Research similar the this new US study is not likely to be possible in NZ due to the small size of the country and uniform MLPA across the country. However other types of evaluation of the change in MLPA need to be done if the law changes.’

Professor Doug Sellman, Director, National Addiction Centre, Otago University at Christchurch, and  Dr Geoffrey Robinson, Chief Medical Officer, Capital & Coast District Health Board, who are medical spokesmen, with Prof Connor, for Alcohol Action NZ:

“People who begin drinking earlier in their lives are more likely to kill themselves or someone else later in their lives – not particularly surprising. But what was startling was the finding that raising the purchase age of alcohol was associated with a decrease in suicide and homicide rates years later”.

“Those who lived in states with lower drinking ages remained at elevated risk for suicide and homicide as adults compared with those who lived in states where the purchase age was raised to 21 years. The association was particularly strong for women”.

“While there are inherent limitations to research like this, other influences on changing rates of suicide and homicide have been carefully considered in the report and the results clearly suggest that there are more long-term consequences of encouraging young people to drink than we previously thought”.

“Raising the purchase age is one of the measures known to be effective in reducing harm to the well-being of young people, and this research reminds us that the damage continues into later life for a substantial number.”

“We need to raise the purchase age in New Zealand even though dismantling the heavy drinking culture will require other major changes as well”.

“It is for this reason that Alcohol Action has commended Hamilton West National MP Tim Macindoe on his supplementary order paper to raise the purchase age up to 20 in New Zealand, for
both on-licence- and off-licence premises”, added Professor Sellman. “This is likely to be debated early in the next term of Parliament, when the 3rd Reading of the Alcohol Reform Bill occurs”.

“However, while we continue to have ultra-cheap alcohol, available virtually 24/7, pushed along by the best marketing science available to the alcohol industry, and while driving when intoxicated
remains legal for adults, we will all continue to suffer the consequences of alcohol, directly or indirectly in New Zealand”.

“Given that the age of purchase of alcohol is likely to be raised quite soon, but more substantial alcohol reforms may take a little longer, it would be prudent to put into place now research that can measure the impact of raising the purchase age alone” commented Dr Robinson.  “We would predict that the overall heavy drinking culture is unlikely to be significantly impacted on by raising the purchase age alone, but there will be some important health gains for young people”.