Attention-deficit hyperactivity disorder (ADHD) can have a considerable impact on the day-to-day functioning and overall wellbeing of people affected. It causes a variety of symptoms including difficulty focusing, impulsivity and hyperactivity.

For many, a diagnosis of ADHD, whether in childhood or adulthood, is life changing. It means finally having an explanation for these challenges, and opens up the opportunity for treatment, including medication.

Although ADHD medications can cause side effects, they generally improve symptoms for people with the disorder, and thereby can significantly boost quality of life.

Now a new study has found being treated for ADHD with medication reduces the risk of early death for people with the disorder. But what can we make of these findings?

A large study from Sweden

The study, published this week in JAMA (the prestigious journal of the American Medical Association), was a large cohort study of 148,578 people diagnosed with ADHD in Sweden. It included both adults and children.

In a cohort study, a group of people who share a common characteristic (in this case a diagnosis of ADHD) are followed over time to see how many develop a particular health outcome of interest (in this case the outcome was death).

For this study the researchers calculated the mortality rate over a two-year follow up period for those whose ADHD was treated with medication (a group of around 84,000 people) alongside those whose ADHD was not treated with medication (around 64,000 people). The team then determined if there were any differences between the two groups.

What did the results show?

The study found people who were diagnosed and treated for ADHD had a 19% reduced risk of death from any cause over the two years they were tracked, compared with those who were diagnosed but not treated.

In understanding this result, it’s important – and interesting – to look at the causes of death. The authors separately analysed deaths due to natural causes (physical medical conditions) and deaths due to unnatural causes (for example, unintentional injuries, suicide, or accidental poisonings).

The key result is that while no significant difference was seen between the two groups when examining natural causes of death, the authors found a significant difference for deaths due to unnatural causes.

So what’s going on?

Previous studies have suggested ADHD is associated with an increased risk of premature death from unnatural causes, such as injury and poisoning.

On a related note, earlier studies have also suggested taking ADHD medicines may reduce premature deaths. So while this is not the first study to suggest this association, the authors note previous studies addressing this link have generated mixed results and have had significant limitations.

In this new study, the authors suggest the reduction in deaths from unnatural causes could be because taking medication alleviates some of the ADHD symptoms responsible for poor outcomes – for example, improving impulse control and decision-making. They note this could reduce fatal accidents.

The authors cite a number of studies that support this hypothesis, including research showing ADHD medications may prevent the onset of mood, anxiety and substance use disorders, and lower the risk of accidents and criminality. All this could reasonably be expected to lower the rate of unnatural deaths.

Strengths and limitations

Scandinavian countries have well-maintained national registries that collect information on various aspects of citizens’ lives, including their health. This allows researchers to conduct excellent population-based studies.

Along with its robust study design and high-quality data, another strength of this study is its size. The large number of participants – almost 150,000 – gives us confidence the findings were not due to chance.

The fact this study examined both children and adults is another strength. Previous research relating to ADHD has often focused primarily on children.

One of the important limitations of this study acknowledged by the authors is that it was observational. Observational studies are where the researchers observe and analyse naturally occurring phenomena without intervening in the lives of the study participants (unlike randomised controlled trials).

The limitation in all observational research is the issue of confounding. This means we cannot be completely sure the differences between the two groups observed were not either partially or entirely due to some other factor apart from taking medication.

Specifically, it’s possible lifestyle factors or other ADHD treatments such as psychological counselling or social support may have influenced the mortality rates in the groups studied.

Another possible limitation is the relatively short follow-up period. What the results would show if participants were followed up for longer is an interesting question, and could be addressed in future research.

What are the implications?

Despite some limitations, this study adds to the evidence that diagnosis and treatment for ADHD can make a profound difference to people’s lives. As well as alleviating symptoms of the disorder, this study supports the idea ADHD medication reduces the risk of premature death.

Ultimately, this highlights the importance of diagnosing ADHD early so the appropriate treatment can be given. It also contributes to the body of evidence indicating the need to improve access to mental health care and support more broadly.

Hassan Vally, Associate Professor, Epidemiology, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

“What are the main factors in forming someone’s personality?” – Emma, age 10, from Shanghai

Hello Emma, and thank you for this very interesting question!

Let’s start by exploring what we mean by personality. Have you noticed no two people are completely alike? We all see, experience, and understand the world in different ways.

For example, some people love spending time with friends and being the centre of attention, whereas other people are more shy and enjoy having time to themselves.

Your unique personality is shaped by your genes as well as various influences in your environment. And your personality plays an important role in how you interact with the world.

The big five

Did you know there are scientists who spend time researching personality? Their research is concerned with describing the ways people differ from each other, and understanding how these differences could be important for other parts of life such as our health and how well we do in school or at work.

There are many different perspectives on personality. A widely accepted viewpoint based on a lot of research is called the five factor model or the “big five”. According to this theory, a great deal of a person’s personality can be summarised in terms of where they sit on five dimensions, called traits:

1. the introversion-extraversion trait refers to how much someone is outgoing and social (extroverted) or prefers being with smaller groups of friends or focusing on their own thoughts (introverted)
2. agreeableness captures how much someone tends to be cooperative and helps others
3. openness to experience refers to how much a person is creative and enjoys experiencing new things
4. neuroticism describes a person’s tendency to experience negative feelings, like worrying about things that could go wrong
5. conscientiousness encompasses how much a person is organised, responsible, and dedicated to things that are important to them, like schoolwork or training for a sports team.

A person can have high, low, or moderate levels of each of these traits. And understanding whether someone has higher or lower levels of the big five can tell us a lot about how we might expect them to behave in different situations.

So what shapes our personalities?

A number of factors shape our personalities, including our genes and social environment.

Our bodies are made up of many very small structures called cells. Within these cells are genes. We inherit genes from our parents, and they carry the information needed to make our bodies and personalities. So, your personality may be a bit like your parents’ personalities. For example, if you’re an outgoing sort of person who loves to meet new people, perhaps one or both of your parents are very social too.

Personalities are also affected by our environment, such as our experiences and our relationships with family and friends. For example, some research has shown our relationships with our parents can influence our personality. If we have loving and warm relationships, we may be more agreeable and open. But if our relationships are hurtful or stressful, this may increase our neuroticism.

Another study showed that, over time, young children who were more physically active were less introverted (less shy) and less likely to get very upset when things don’t go their way, compared to children who were less physically active. Although we don’t know why this is for sure, one possible explanation is that playing sport leads to reduced shyness because it introduces children to different people.

While we’re learning more about personality development all the time, research in this area presents quite a few challenges. Many different biological, cultural and environmental influences shape our development, and these factors can interact with each other in complex ways.

Is our personality fixed once we become adults?

Although we develop most of our personality when we are young, and people’s personalities tend to become more stable as they get older, it is possible for aspects of a person’s personality to change, even when they are fully grown.

A good example of this can be seen among people who seek treatment for conditions like anxiety or depression. People who respond well to working with a psychologist can show decreases in neuroticism, indicating they become less likely to worry a lot or feel strong negative feelings when something stressful happens.

Hello, Curious Kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to mailto:curiouskids@theconversation.edu.au

Tim Windsor, Professor, Director, Generations Research Initiative, College of Education, Psychology and Social Work, Flinders University and Natalie Goulter, Lecturer, College of Education, Psychology and Social Work, Flinders University

This article is republished from The Conversation under a Creative Commons license. Read the original article.