Monday, October 28, 2013 C9
HEALTH
CRAVE
LAB REPORT
As scientists identify new addictions, they also discover fresh treatments for harmful behaviour, writes David Tan
............................................ Jeanette Wang jeanette.wang@scmp.com
MENTALITY
A
ddiction comes in many forms: drugs, alcohol, cigarettes, and gambling have been the types that traditionally plagued society. In recent years, the proliferation of technology has led to the rise of addiction to the internet and computer gaming. Even the promotion of a healthy lifestyle has led some to become hooked on exercise. But do all addictions operate by the same biological mechanism? And is addiction an individual’s choice or a disease of the brain? Scientists have been studying addiction for years in order to improve treatments for harmful behaviour. They have found that powerful memories, often of highly pleasurable or intense experiences, underlie addiction. During such experiences the brain releases a chemical called dopamine that creates a reward circuit in the brain, by logging the intense experience as pleasurable and an important action to be repeated. Dopamine release generally occurs in a region called the ventral tegmental area (VTA). In response to this, epigenetic changes happen in brain nerve cells to form reward memories. These chemical changes are a mix of DNA methylation and demethylation, which either turns genes off or on. Such a system allows changes in how genes are expressed in cells without altering our genetic code, and forms a type of genetic memory. Addiction to all four major classes of abused substances – psychostimulants, opiates, alcohol and nicotine – has been linked to the same parts of the brain associated with normal reward processing. Because of this, scientists originally thought that drug addiction took over normal reward memory nerve pathways. However, a more nuanced picture is now emerging. In normal reward processing, the VTA signals to another region of the brain called the nucleus accumbens (NAC). So when scientists blocked methylation changes in both these regions in rat brains, they expected to block reward memory formation. Surprisingly, this happened only when the VTA was blocked, but not the NAC. This points to a distinction in the chemical regulation of reward circuits in normal reward responses versus addiction responses. Dr Jeremy Day from the University of Alabama at Birmingham, who led the study, says: “Although drug experiences may co-opt normal reward
mechanisms to some extent, our results suggest they also may engage entirely separate epigenetic mechanisms that contribute only to addiction and that may explain its strength.” According to the Central Registry of Drug Abuse, opiates – such as heroin – have been the most common drug abused in Hong Kong; however, rates of heroin abuse have been dropping. In its place, psychotropic substances – which cross the blood-brain barrier and act primarily upon the central nervous system – such as cocaine, ketamine and methamphetamine, have become the drugs of choice. Alcohol consumption peaked in 2008 before decreasing in recent years, according to a survey by the Health Department. Smoking has seen a falling trend: cigarette smoking prevalence dropped to a 30-year low of 11.1 per cent in 2010. While abusing drugs, alcohol and nicotine typically kills you gradually, another well-known addiction that can kill quickly is gambling, whether in casinos or on the stock market. In Hong Kong, a 2010 study found that almost half of gambling suicides in the city were associated with large gambling debts. Now, a new form of addiction is ensnaring youths and adolescents with the spread of the internet, gaming technology and smartphones. Professor Daniel Shek Tan-lei at Polytechnic University conducted a study in 2011 that found 26.7 per cent – just over a quarter – of 3,500 students interviewed were considered addicted to the internet. Dr Alain Dagher, of McGill University, believes that abnormal interactions between different decision-making regions in the brain are the underlying cause of addiction. A specific region in the brain called the dorsolateral prefrontal cortex regulates feelings of craving in response to cues. For
example, a smoker craves a cigarette when they see or smell someone else smoking. By visualising how an addicted person perceives a substance, the imaging results can be used to predict consumption. Applying a technique called transcranial magnetic stimulation, a method that uses magnets to induce weak electric currents in the brain without any form of surgery, the dorsolateral prefrontal cortex can be inactivated – and the craving response can be altered. Dagher says: “Policy debates have often centred on whether addictive behaviour is a choice or
Debates often focus on whether addiction is a choice or a brain disease DR ALAIN DAGHER, SCIENTIST
26.7% of 3,500 Hong Kong students interviewed in a 2011 study were addicted to the internet
a brain disease. This research allows us to view addiction as a pathology of choice. Dysfunction in brain regions that assign value to possible options may lead to choosing harmful behaviour.” Treatment of addiction requires a multi-pronged approach. These include the gradual reduction of the abused substance with the aim of total abstinence, and counselling services. Experts agree a key aspect of addiction treatment is social and family support. Dr Bonnie Lee, associate professor at the University of Lethbridge in Canada, believes that instead of treating addiction
in individuals, help should be administered at the group level. Lee has developed Congruence Couple Therapy, a model adopted by treatment agencies in Canada, and which Lee has taken to places around the world, including Hong Kong. “One could say relationship breakdown is the root of addiction in most cases, often originating in childhood with abuse, neglect and abandonment,” she says. “I like to see how family members talk to each other. Like a stage director, I reshape the family interactions to promote mutual understanding of fears and hurts, as well as the sharing of hopes and wishes. “This collaborative spirit then propels the therapy forward because there is hope when everyone works together with realistic expectations.” Lee believes congruence therapy is particularly apt for Asia. “Asian values prize the family as the cornerstone for individual and societal harmony and well-being. “The Taoist worldview of interconnections resonates with contemporary ‘systems thinking’ in addressing the individual as inseparable from couple and intergenerational relationships. “There is a lot in congruence therapy that would appeal to Asian clinicians and clients.” To treat addiction in youths, Shek also believes family support to be paramount. Referring to youth development programmes in Hong Kong, he says: “Most focus on life skills training, such as emotional management. Family intervention is also an effective intervention direction.” In Hong Kong, according to Shek’s 2011 report, a youth development programme aimed at secondary school students called Project PATHS made good headway in reducing adolescents’ delinquent behaviour and substance use, while increasing psychosocial competencies and their ability to control internet use. As time passes, new types of addiction may become traditional, while newer ones appear on the horizon. Although addiction may be multifaceted, scientists are discovering common underlying pathways in the brain that can help shape treatment options. By focusing rehabilitation efforts on family and social support, we are becoming better equipped to battle addiction, regardless of its shape or form. life@scmp.com
Downward spiral Almost nine out of 10 people in Hong Kongs have deteriorating health, according to a survey commissioned by insurance company AIA Group. In the poll of 600 Hongkongers, 86 per cent said their health was not as good as five years ago. It’s the highest rate in the region, where 10,245 adults aged 18 to 65 years across 15 territories were surveyed. Although 65 per cent of Hongkongers indicated a desire to lose weight, eight in 10 said spending time online prevented them from getting enough exercise. Among Hongkongers under the age of 30, only 61 per cent exercised regularly at an average of 2.3 hours per week.
No pregnant pauses Women who exercise during pregnancy could be setting their child up for better heart health in adulthood, according to a new study in the journal Experimental Physiology. The American Congress of Obstetricians and Gynaecologists recommends 30 minutes of moderate intensity physical activity on most or all days of the week. In the study, pregnant pigs exercised 20 to 45 minutes on a treadmill for five days a week. The regimen had a major effect on vascular function in the swine’s adult offspring, which the researchers say may have implications for future risk of cardiovascular disease.
Correction In the article on flat-head syndrome titled “Out of shape”, published on October 9, 2013 in the South China Morning Post, Dr Hannah Tsang Yee-hoi, a specialist in paediatrics, was misquoted as saying that syndromal disorders were anxiety and depression. This is incorrect. Examples of syndromal disorders are Apert syndrome and Down’s syndrome. These are just two examples of syndromes that need to be ruled out by the absence of other clinical features before a child can be diagnosed as having positional plagiocephaly.
Diagnostic inflation: when quirks label us as crazy ................................................ David Wilson life@scmp.com Today it seems that almost everyone is certifiably mad. According to critics, amateur and professional psychiatrists are routinely guilty of “diagnostic inflation”: turning normal people into mental patients with alphabet soup diagnoses. In a new book, America’s Obsessives, author Joshua Kendall argues that many great people have been shaped by obsessive compulsive personality disorder. Other widely applied questionable labels include disruptive mood disregulation disorder, which may mean nothing more than children’s temper tantrums, and social anxiety disorder, which may be shyness. Thanks to psychiatric overreach, every quirk is judged a mental disease, especially if the US$300-billion-a-year pharmaceutical sector has a pill for it, the theory goes. Meet florist Caren Ragan, who says she has taken every psychiatric test under the sun. Much mental health diagnosis is subjective, Ragan says. Her mental health ordeal stemmed from declaring her intention to divorce her
ex-husband who, at the start of a 10-year court battle, branded her “paranoid-delusional”, she says. Six times during her ordeal, Ragan took one of the most commonly used personality tests in mental health: the Minnesota Multiphasic Personality Inventory. Her answers were consistent, she says, but the diagnosis depended on the examiner. The verdict varied from “normal” to severe psychosis with paranoid delusions. “Which was pretty strange considering I worked, raised a family and volunteered at school and not one single person ever noticed this severe mental disorder,” she says. Ragan adds that she was prescribed several kinds of antidepressants for real, related depression; all worked briefly before she decided she had no time to indulge in emotional problems, which are a luxury of rich countries, she says. In the developed world, the mental health industry is booming. According to psychologist Carole Stovall, an expert in anxiety complaints such as post-traumatic stress disorder, mental health prescription rates have “skyrocketed”. Stovall is appalled that doctors prescribe psychotropic
We should not reduce human experience to a checklist of behaviour PEGGY TILESTON, THERAPIST
drugs to children as young as six months. “This is shameful. Clearly, society is overprescribing,” she says. True, she adds, careful medication can help a patient. But medication is often used “offlabel”, which can be detrimental. All medication has side effects, she says. In fact, medication can make you crazy. According to the mental health watchdog the Citizens Commission on Human Rights, common and well-documented side effects of psychiatric drugs include mania, hallucinations, depersonalisation, suicidal ideation, psychosis, heart attack, stroke and sudden death. The view that psychiatrists recklessly medicate first and ask questions later, pathologising
normality, is fuelled by an oftcited Canadian study. Children born in December, close to the cut-off date for entry into British Columbian schools, were 39 per cent more likely to be diagnosed with attention deficit hyperactivity disorder (ADHD) than children born 11 months earlier, the study found. The University of British Columbia researchers deduced that younger students were diagnosed with ADHD because of their youth. The finding suggested that the education system is medicalising immaturity.
According to the leading critic of diagnostic inflation, Allen Frances, we can cope with plenty of pain because the brain is naturally resilient and self-healing – given time, people get through rough patches. Newly invented conditions such as “major depressive disorder”, which is grief in Frances’ view, worsen a cruel mental health industry paradox: people desperately needing help wilt unaided while the “worried well” win the bulk of the treatment, often to their
detriment, says the blurb for Frances’ book, Saving Normal. Defenders of labelling, including the influential clinical psychiatry professor Ronald Pies, contest that it draws flak for a suspect reason: society fears, misjudges and reviles mental illness, he claims. According to City University of Hong Kong social scientist Daniel Wong, speaking in a 2011 BBC interview, mention of mental illness makes people think of danger and murderous violence. So, some of the doubt about diagnosis may stem from prejudice. Therapist Peggy Tileston reckons that the psychiatric profession merits some credit. “I have witnessed much good, including lives literally saved, lives turned around for the better, resulting from conscientious, caring and skilled psychiatrists accurately diagnosing and prescribing appropriate types and levels of medication for people with serious mental health conditions,” Tileston says. Still, she has qualms. While we no longer shut people away in deplorable asylums, we still have a long road ahead. “We still know so little about
the vastness of who we are as human beings. It’s very quick, convenient, clean and comforting to organise, categorise, and standardise human experience,” she says. “But we cannot and should not reduce our messy and multidimensional human experience to a checklist of symptoms and behaviour. “The danger is that we miss the unique person sitting right there in front of us, or we see only what’s wrong and different from the norm,” she says. Cue medication. A diagnosis and a pill or product now exists for almost any human experience, according to Tileston. “Have a human condition that makes you or me uncomfortable? There’s a pill for that!” she says, adding that over-diagnosis discourages accepting what being fully human means. The reason for the alleged clinical bias is a growing group intolerance towards any experience outside an increasingly narrow range judged “appropriate” or “normal”, Tileston says. She approvingly quotes a patient who told her: “Normal is a setting on a washing machine, and not applicable to creative individuals like me.”