Research news in brief

Teen drug use doesn’t affect future life success when stopped early

Young people who use drugs but quit by early adulthood are, on average, not harming their future life chances, according to Australian research which tracked thousands of people over a 16-year period. Published in Addiction Research and Theory, the study aim was to examine the extent cannabis and amphetamine use up to age 21 years predicts life success at age 30. This is after taking into account a wide range of prior life experiences and behaviour. The authors used data on 2350 children born to mothers in the Mater-University of Queensland Study of Pregnancy which began 40 years ago and has followed up participants at key life stages. The children were tested at 14 years for IQ, mental health, and aggression/delinquency. Information from mothers was also analysed such as number of partners and child’s contact with police. Cannabis and amphetamine use was self-reported at specific age points (21 and 30 years). The authors also interviewed participants at age 21 years about behaviours linked to past drug-taking (eg, drug-related disorder). Life success was measured at age 30 years and defined according to three categories: socio-economic, quality of life, and quality of intimate relationships. The results show that more than one in five (22%) had ever had a cannabis use disorder and 4% problematic amphetamines use. Age of onset ranged from 15 to 19 years and the participants reported high levels of drug use. The proportion of participants at age 21 years who reported problematic drug use was 19% for cannabis, 0.7% for amphetamines, and 3% for those using both drugs. Of these, the issues persisted at age 30 for more than a third (36%) taking cannabis, and 60% of those using cannabis and amphetamines. A majority of those who had ever met the criteria for problematic drug use were no longer using at clinically significant levels by age 21 years, according to the findings. However, the use of cannabis at age 30 was strongly related to achievement. This was also dose related: high use in adulthood associated with the highest rates of poor life success.

Elderly dog owners almost 50% less likely to have a disability

An analysis of data from more than 11 000 older Japanese adults suggests that seniors who own a dog may be at lower risk of disability than those who have never been dog owners. The study, involving University of Melbourne researchers and published in PLOS One, used questionnaires to collect data on dog and cat ownership from 11 233 Japanese adults aged 65–84 years. Researchers also collected demographic, disability, and other health data for the participants, spanning the period of June 2016 to January 2020. Statistical analysis of the combined datasets enabled them to examine potential links between dog ownership and disability risk. During the study period, older adults who were current dog owners were approximately half as likely to have a disability than those who had never been dog owners. This relationship held true even after accounting for other sociodemographic and health factors that could influence disability risk, such as marital status, history of chronic diseases, time spent outdoors, and more. In addition, dog owners who exercised regularly had an even lower risk of disability. Meanwhile, the researchers found, cat ownership was not associated with any difference in disability risk, and neither dog nor cat ownership was associated with reduced risk of death from any cause. This study suggests that dog ownership—especially combined with regular exercise—may protect against disability for older Japanese adults. These findings could help inform efforts to promote successful ageing. Meanwhile, future research could investigate physical or psychological mechanisms by which dog ownership might provide benefits, or examine relationships between dog ownership and disability risk in other countries.

Serious allergic reactions to food among children stabilise since guideline changes

The rate of increase in serious allergic reactions to food among children has flattened since changes to Australian infant feeding guidelines, a study from the Murdoch Children’s Research Institute, published in the Journal of Allergy and Clinical Immunology, has found. The Australasian Society of Clinical Immunology and Allergy (ASCIA) infant feeding and food allergy prevention guidelines changed in response to published studies over the past 15 years, from a recommendation to “delay” allergenic foods (1999 to 2007) to “not delay” (2008) and then later to “introduce early and often” (since 2016). The study examined national emergency department data for food anaphylaxis during three different time periods from 1998–1999 and 2006–2007, between 2007–2008 and 2014–2015 and between 2015–2016 and 2018–2019. A total of 37 132 anaphylaxis admissions were recorded over the timespan. “In children, aged 1 to 4 years, the yearly rate of increase dropped from 17.6% a year between 1999 to 2007, to 6.2% a year between 2008 to 2015 and then 3.9% a year since 2016,” the authors said. “A slowing in the rates of increase in food anaphylaxis admissions also occurred in those aged 5–14 years, born after the 2008 changes. These changes were not seen in older teens aged 15 and over who were born before 2008, who could not have benefited from the changing guidelines. While we did see a spike in children aged less than one year, this is most likely due to earlier hospital presentations of pre-existing food allergy following introduction of allergenic solids in the first year of life.” The researchers cautioned that it was important not to be complacent, as overall food anaphylaxis hospital admission rates had still increased and there was an unmet need for effective treatments that could induce remission.