New risk tool allows prediction of dementia in elderly

Medical Tribune June 2009 P3

David Brill

A new algorithm could help physicians to stratify elderly patients according to their risk of developing dementia.

The late-life dementia risk index was developed using data from 3,375 subjects with a mean age of 76. Just 4 percent of those classified as low risk developed dementia over 6 years, compared to 23 percent of moderate-risk and 56 percent of high-risk subjects.

"This new risk index … could be used to identify people at high risk for dementia for studies on new drugs or prevention methods,” said lead author Dr. Deborah Barnes, University of California, San Francisco, US. “The tool could also identify people who have no signs of dementia but should be monitored closely, allowing them to begin treatment as soon as possible." [Neurology 2009 May 13; Epub ahead of print]

Greater awareness needed on childhood anxiety disorders

Medical Tribune March 2009 P5
David Brill

Pediatric anxiety disorders are “under-recognized and under-treated” and could be contributing to depression, drug abuse and educational underachievement in later life, a leading US psychiatrist has warned.

As many as 20 percent of children have some sort of anxiety problem but few are likely to be receiving optimal therapy, Professor Graham Emslie wrote in a recent New England Journal of Medicine editorial. [2008 Dec 25;359(26):2835-6]

Specialists at KK Women’s and Children’s Hospital (KKH) in Singapore, where referrals for pediatric anxiety disorders are low but rising, agreed that the problem is under-recognized and called for greater awareness among medical practitioners.

Emslie, a professor of psychiatry and pediatrics at the University of Texas Southwestern Medical Center, said that children often develop avoidance or coping strategies which can mask the true extent of the problem and contribute to the diagnosis being missed. Genuine anxiety disorders may also be dismissed as “normal, developmentally appropriate worries, fears and shyness,” he said.

The success of the CAMS* study, published in the same edition of the journal, highlights that the treatment options for pediatric anxiety are now more effective than ever before, Emslie said. The researchers found that 81 percent of children showed significant improvements in their anxiety levels when cognitive behavioral therapy (CBT) was combined with the selective serotonin-reuptake inhibitor sertraline. [N Engl J Med 2008 Dec 25;359(26):2753-66]

CBT is typically employed as the first line treatment at KKH but may also be combined with medications in severe cases, according to principal psychologist Ms. Frances Yeo. The number of children with anxiety disorders seen at the hospital rose from 26 in 2007 to 48 in 2008.

Yeo noted that the under-recognition of pediatric anxiety disorders may result from children’s inability to vocalize their worries and fears, which may subsequently manifest themselves as behavioral problems and lead to the child being wrongly labeled as lazy or difficult.

“Children usually show signs of their anxiety through physical symptoms such as stomachaches, headaches, hyperventilation, heart palpitations and tightness in the chest. These symptoms are rather vague and can overlap with many other disorders which make it difficult to distinguish,” she added.

“The first step for the medical community is awareness. GPs need to be alert for children with vague physical symptoms which cannot be explained by medical illnesses,” she said.

Pediatric anxiety disorders comprise a spectrum of conditions including social phobias, separation anxiety disorder, and generalized anxiety disorder. Children who are affected at ages 14 – 16 are more likely to have poor educational, mental health and social role outcomes at ages 16 – 21, a study of 1,265 New Zealand adolescents showed. [J Am Acad Child Adolesc Psychiatry 2001 Sep;40(9):1086-93]

Emslie noted that the exposure component seems to be the most effective part of CBT for children with avoidance strategies, suggesting that they should be encouraged to tackle their phobias head on. Doctors have an important role to play in this, he said, adding that they can unwittingly “collude” with avoidance coping by writing medical notes which give anxious children an excuse to miss school.

Dr. Ng Koon Hock, visiting consultant psychiatrist to the Mental Wellness Service at KKH, said that parents may be failing to recognize anxiety disorders because they tend to downplay a child’s emotions and focus overly on their behavior as a disciplinary issue. “There is less tendency to look at things from the child’s perspective,” he said.

Ng believes that doctors are generally reluctant to liberally grant medical leave to children who regularly makes suspicious-looking health complaints, but noted that this can be a difficult balancing act.

“If the child is very stressed and wants to escape from the problem then in the long-term it’s not helpful, but sometimes it does allow them to get by in the short term,” he said.

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*CAMS: Child-Adolescent Anxiety Multimodal Study

Simple strategy effective in postpartum depression screening

Medical Tribune February 2009 P16
David Brill

Combining two existing screening tools could be a straightforward, time-saving and effective way to detect postpartum depression (PPD) in primary care, US research has shown.

The first screening stage, comprising two simple yes/no questions, was 100 percent sensitive at detecting PPD, according to the Annals of Family Medicine study. [2009; 7:63-70]

Patients with a positive result on the two-question screen should then progress onto the nine-item Patient Questionnaire (PHQ-9), say the University of Minnesota researchers, who report that this second stage was 92 percent specific. They tested the two-tiered strategy in 506 women who brought their newborn infants for well-child visits at pediatric and family medicine clinics over the course of 9 months.

The screening tools have already been incorporated into routine practice at several Minnesota clinics and are soon to be implemented in three large hospitals, according to Dr. Dwenda Gjerdingen, who led the study.

“We find them easy to administer, patients find them easy to complete, and they give us a good sense of where the patient is at in terms of their mental health,” she said.

“You want your initial screen to be highly sensitive, which this one is: the two-question screen does not miss depressed patients. Then the PHQ-9 is a very specific test so when depressed people complete it and it turns out to be positive, it is likely to be a true positive and not a false positive.”

The two-question screen focuses on the main symptoms of depression: diminished mood and loss of pleasure in activities.

Despite the common nature of PPD – the condition affects around 22 percent of new mothers and is the most common complication of childbirth – less than half of mothers are presently being screened, the authors wrote. The condition not only affects the mother’s wellbeing but can also harm the cognitive development of the infant. [Arch Womens Ment Health 2003 Nov;6(4):263-74]

The results of the new strategy were validated against the Structured Clinical Interview from the Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV. Forty-five (8.9 percent) of the women were found to have major depression.

Gjerdingen noted that the PHQ-9 still missed a few depressed patients, so suspicion should be retained in those who achieve a negative result having scored positively on the initial two-question screen. These women should be advised to see their doctor if they experience a dip in mood, she said.

Both the two-question screen and the PHQ-9 are already used in general depression but had yet to be validated in PPD. Other potential screening options for PPD are available but typically take longer to complete, Gjerdingen said.

Voluntary counseling could help doctors avoid burnout

Medical Tribune January 2009 P5
David Brill

Short counseling sessions can reduce burnout among doctors and encourage them to make positive changes to their working lives, a new study suggests.

Doctors who volunteered for an intervention program in Norway reported lower levels of emotional exhaustion, worked fewer hours per week and were less likely to be on full-time sick leave a year later.

They were also more likely to seek further professional help, with 53 percent having undergone psychotherapy at 1-year follow-up compared to just 20 percent at the time of enrollment.

Many had already reached high levels of distress and had considered attending the program for quite some time before actually doing so, according to Dr. Karin Rø of the University of Oslo, who led the study.

“The program legitimizes the need for doctors to take a step back for a while and think about their situation,” she said.

“A lot have come back to me and said that it was really important at that time in their life to have somebody to talk to, to get a different perspective on their own situation. Giving a little help, in time, is much better than having to give a lot of help when the situation is much worse.”

Volunteers at Villa Sana – the only center of its kind in Norway – chose between a single one-on-one counseling session of around 6 hours, or a week-long course involving daily lectures followed by group discussions. All sessions were confidential and no medical records were kept. A total of 227 doctors were included in the study, 185 of whom completed 1-year follow-up questionnaires. [BMJ 2008 Nov 11;337:a2004]

Dr. Sim Kang, a consultant psychiatrist at the Institute of Mental Health, Singapore, hailed the research as an important reminder of a timely issue.

“The healthcare profession is certainly susceptible to the onset of burnout if one is not careful about it. The demands of the job are changing and the expectations are quite high from the public nowadays,” he said.

“The symptoms of burnout encroach not just upon the sense of physical tiredness but also the sense that one is mentally wearied and emotionally drained. The message is that if prevention isn’t working and things are getting out of hand then they should seek help.”

Another BMJ study published this year reported that depressed pediatric residents made six times as many medication errors per month as non-depressed residents. [2008 Mar 1;336(7642):488-91]

Rø pointed to this finding as evidence that doctors need to take care of their own wellbeing in order to take care of others.

“When you fly on a plane and the oxygen masks come down you’re supposed to put your own one on before you help anyone who needs it. I think that’s a very good picture of doctors,” she said, adding that she hopes the study will prompt the creation of other similar centers in future.

A year on from the intervention the participants had reduced their mean working hours by an average of 1.6 hours per week. Just 6 percent were on full time sick leave, compared to 35 percent at baseline.

High rates of depression and suicide have been well documented among doctors. A recent study of Brazilian medical students found that as many as 38.1 percent had depressive symptoms, with females particularly susceptible. [BMC Medical Education, in press]

Rø noted that the Norwegian counseling intervention helped the doctors to normalize their situation, having previously felt that they were the only ones experiencing such feelings of distress. They often fail to seek help because they are used to focusing solely on the needs of their patients and do not realize when they are in need of help themselves, she said.

The exact prevalence of depression among the medical community in Asia is largely unknown.

However, Sim encouraged doctors to discuss their feelings of stress and anxiety in informal support groups with their peers whenever possible, adding that he would like to see longer-term data on the sustainability and generalizability of the Norwegian model before advocating the adoption of more formal, structured programs.



Seven tips for avoiding burnout

Dr. Sim Kang, a consultant psychiatrist at the Institute of Mental Health, Singapore, offers his advice on how to de-stress before it gets too late.

1 – Acknowledge and accept that we are all equally vulnerable and can feel trapped and overwhelmed like anyone else. Medical professionals are not superheroes.

2 – Be willing to communicate with others, particularly through informal networks of colleagues, family and friends.

3 – Clarify your responsibilities within the job and resolve any ambiguities that may be causing additional stress.

4 – Determine your own strengths and weaknesses and play to them.

5 – Educate yourself about the symptoms of burnout.

6 – Find time off to unwind and relax.

7 – Group together with your peers to discuss the difficult issues and identify any problems you may be experiencing.

Chronic disease management: Depression

Medical Tribune November 2008 P14-15

Depression is a serious global health issue. Some 121 million people are affected worldwide, according to 2001 estimates from the WHO, with 1 million committing suicide each year and a further 10 to 20 million attempting to do so.

The prevalence of depression in the general adult population of Singapore is around 5 percent. This figure is lower than in the US but comparable to most developed European countries. The prevalence in developing Asian countries is unclear but is likely to rise, placing an increasing burden on society and healthcare systems.

The WHO, as part of a new program launched on World Mental Health Day 2008, recently called on governments and donors to urgently upscale mental health services and better integrate mental health into primary care. Depression in particular is increasingly treatable, and making an early and effective diagnosis in this setting will lead to considerable improvements in outcome.

Diagnosis

Routine screening for depression is not recommended but should be carried out among those who are at the highest risk. There are several risk factors which GPs should be aware of in order to effectively target these patients.

The presence of multiple medical problems is strongly associated with depression. Chronic but stable conditions such as heart disease, stroke and cancer all place a strain upon patients’ wellbeing, and the coexistence of more than three conditions has been shown to significantly increase depression risk.

The link between depression and diabetes, for example, is well established. Depressed patients often lose the motivation to take their medications, which contributes to a worsening of their diabetes. This can be a two-way process, with the resulting deterioration of blood sugar control affecting the vessels and tissues in the brain, leading to a further worsening of depressive symptoms and an even greater loss of motivation.

GPs should also consider the social factors affecting their patients, as this type of information is invaluable in identifying those who should be screened for depression. Do they live alone? Are they recently divorced or widowed? Is there support from their family? Are they likely to have financial problems?

Once the GP has identified a high-risk patient they can initiate screening with two quick, simple questions: “Have you persistently felt depressed in the last 2 weeks to a month? Have you experienced a loss of interest in your daily activities over this time period?” If the patient answers yes to either of these questions then the physician should move on to try and identify further symptoms. A formal diagnosis can then be established according to the criteria laid out in the relevant guidelines.

There are, however, two major obstacles to initiating this process. The first is shyness on the part of the patient. Asian patients tend to perceive doctors as being primarily concerned with their physical wellbeing and may not expect to discuss mental health issues with them. They are often shy and might find the subject awkward.

Doctors nonetheless have a responsibility to overcome this barrier and broach the subject. This can be done by gradually and tactfully guiding the conversation in the right direction. Ask the patient gently about their mood, how they have been feeling in light of recent problems, and whether there are any other issues they would like to discuss. If they clam up, try not to charge in and pry them open in a single visit. Primary care physicians have the advantage of seeing patients regularly, and introducing the subject in one visit might make it easier to return to at a later date.

The second barrier, however, lies with the doctor, since the process of diagnosing depression can only begin if they are willing to ask these difficult questions. There is sometimes a reluctance to open up Pandora’s Box which, although understandable, needs to be overcome. This fear typically lies in the unknown, so doctors can avoid this by reading around the subject and being prepared for what might follow. Continuing Medical Education courses and workshops are often available to help physicians gain confidence in dealing with these issues, while there is a wide range of useful information available on the internet for further reading (see below).

Once doctors are comfortable with broaching the subject they can also use their intuition to guide them in making an early diagnosis. Depressed patients may seem withdrawn and quieter than usual, or may display a steady deterioration in chronic conditions which were previously well controlled. These signs should all arouse suspicion that the patient is not simply having a bad day and may be in need of help.

Practice Guidelines

Practice guidelines on major depressive disorder are available from the American Psychiatric Association website. The Ministry of Health in Singapore also publishes its own guidelines on depression, most recently in March 2004. These state that a diagnosis can be made when a depressed mood or loss of interest is accompanied by a minimum of four specific symptoms (from a list of eight) over a period of 2 or more weeks.

Depression can be a culturally sensitive issue, and guidelines will need to be applied within the context of the local social environment. The ability to adhere to the various guidelines will also depend heavily on the availability of local resources.

A range of advice and information is also available from the Malaysian Psychiatric Association and the Hong Kong College of Psychiatrists.

Treatment

Once the criteria for diagnosis are fulfilled GPs should move on to discuss treatment with their patients. If the patient is not severely agitated or suicidal then it can be useful to spread this discussion over more than one clinic visit. Start by making them aware that they have a medical condition which goes beyond just experiencing difficulties in life, and let them know that it is treatable and that safe and effective medications are available. This will give the patient time to digest the information, discuss the options with their family and do their own research before committing to a plan of action.

This approach also gives the GP a little more time to review options and prepare for prescribing an antidepressant. Medication access and guidelines will vary by country, but GPs should typically aim to begin with a selective serotonin reuptake inhibitor (SSRI) or a tricyclic antidepressant (TCA) for 4 to 6 weeks and wait to see whether there is a response. Algorithms such as the Texas Implementation of Medication Algorithm (see below) can then be used to guide further decisions around medication use.

Patients may have common misunderstandings about medications which physicians should try to allay. They may fear that the medications are addictive, or they may expect them to provide instantaneous relief. Managing these expectations in advance is important, and can help prevent patients from becoming disappointed or frustrated and stopping their medications.

Close follow-up is also crucial. Guidelines suggest that medication use should continue for 6 months to a year even if the patient shows signs of recovery. Early discontinuation leads to a higher risk of relapse, so it is important to make sure that patients finish their course. Side effects such as gastrointestinal complaints, drowsiness, dry eyes and dry throat will also need to be managed and patients should be warned about these in advance.

Psychotherapy, where available, is also a useful tool for treating depression. Few GPs are trained in psychotherapy themselves, and they should prepare for this eventuality by thoroughly researching the options in the local community and knowing how and where to refer their patients.

Treatment can be augmented by attempting to tackle some of the underlying triggers for depression. Rather than focusing solely on medical issues, GPs should also explore a patient’s psychosocial problems to understand what is troubling them. Community resources and support groups may be on hand to help, and many patients will benefit from further advice and referrals. With patients facing many problems this approach can be time-consuming for GPs, and they may like to plan ahead and deal with these issues one session at a time.

Patients with multiple psychiatric disorders or very complex or refractory depression should generally be referred on to a specialist center, particularly if they show signs of suicidal thoughts or self-harming behavior.

These centers may also offer further training which can help primary care physicians to improve their knowledge of depression. The Institute of Mental Health, for example, offers a partnership program for GPs which seeks to provide continuity of care for stable patients and increase the accessibility of treatment within the community. Participants complete a series of lectures and guided clinical sessions on depression and other mental health disorders, and can subsequently receive case consults and phone advice for difficult cases. Having specialist advice on hand can take some of the pressure off busy GPs, and can help them feel more comfortable discussing depression with their patients.

Conclusion

Depression is becoming easier to treat as our understanding of the condition continues to improve. Medications are safer and more effective than ever before and there is a wide range of information available to guide our clinical decisions. Primary care is an important setting for making an early diagnosis, and physicians should be proactive in screening patients who are at high risk.


Online Resources:

The American Psychiatric Association practice guidelines:
http://www.psych.org/MainMenu/PsychiatricPractice/PracticeGuidelines_1.aspx

The World Psychiatric Association:
http://www.worldpsychiatricassociation.org/

Texas Implementation of Medication Algorithm (TIMA):
http://www.dshs.state.tx.us/mhprograms/disclaimer.shtm

Institute of Mental Health patient information: http://www.imh.com.sg/patient_education/depression.htm

Depression.com:
http://www.depression.com/

Antipsychotic drugs raise risk of stroke

Medical Tribune October 2008 P3

Stroke risk is raised by all antipsychotic drugs and not just atypical types as previously thought, according to UK researchers.

Electronic primary care records were used to identify 6,790 patients with a history of stroke and taking antipsychotic medications. Compared to non-medicated periods, the rate ratio for stroke when taking any antipsychotic drug was 1.73 (95% CI 1.60 – 1.87). For typical antipsychotics alone the ratio was 1.69 (95% CI 1.55 – 1.84), whereas for atypical drugs alone this figure was 2.32 (1.73 – 3.10).

Patients with dementia who took any antipsychotic were at markedly increased risk for stroke (rate ratio 3.50; 95% CI 2.97 – 4.12), and the authors advise that these drugs be avoided where possible in these patients. [BMJ 2008 337:a1227]

Hormone patch improves schizophrenia symptoms

Medical Tribune October 2008 P5
David Brill

Estrogen – often blamed when women behave irrationally or emotionally – could in fact turn out to be an effective treatment for those with mental illness.

Researchers from Australia have shown that estradiol, delivered in the form of skin patches, can alleviate psychotic symptoms in schizophrenic women of childbearing age.

In a randomized trial with 102 participants, those given the patches alongside their regular medications showed significant reductions in both positive and general psychopathological symptoms compared to those on placebo. In many cases the effects were rapid, with hallucinations improving within 2 or 3 days of starting treatment. Improvements in memory and the ability to think clearly about complex issues were also commonly reported following treatment.

Professor Jayashri Kulkarni, who led the study, said that the benefits of hormone therapy might extend to other mental illnesses such as postnatal depression.

She added that further research into the role of estrogen for treating schizophrenia is still needed, but suggested that the hormone could already be used for certain women who have reached a plateau with antipsychotic drugs.

“Even as the data stand there is enough to suggest that for women who have tried standard treatments and haven’t made a brilliant recovery, it is possible and useful for clinicians in everyday practice to think about using a hormonal approach,” said Kulkarni, who is director of the Alfred Psychiatry Research Centre at The Alfred and Monash University in Melbourne. She added, however, that close monitoring for the long-term side effects of estrogen therapy would be needed in such cases.

Participants in the trial were assigned in a double-blind fashion to receive transdermal patches – containing either placebo or 100 μg estradiol – alongside their regular antipsychotics. [Arch Gen Psychiatry 2008 Aug;65(8):955-60]

The trial lasted for 28 days. No notable differences in adverse effects were recorded between the estradiol and placebo groups. Outcomes were assessed using the Positive and Negative Syndrome Scale (PANSS).

The mechanisms for the estrogen effect are unclear, but the researchers suggest that the hormone could rapidly enhance blood flow to the brain and improve cerebral glucose metabolism. Alternatively the effect may be mediated through modulation of the dopamine or serotonin neurotransmitter systems, or through the remodeling of neural pathways, they wrote.

“The other thing that was really interesting was that we didn’t have much problem recruiting for the study,” Kulkarni added.

“Many women patients have intuitively noted a change in their body menstrual cycle and associated that with changes in their mental state, so when we offered something
that seemed to fit with that sort of intuition it was really taken up very well by the patients,” she said.

Topiramate effective for treating alcohol dependence

Medical Tribune August 2008 SFIX
David Brill

A randomized trial has shown that topiramate can improve the physical and mental wellbeing of alcoholics as well as reducing their drinking behaviour.

Patients who took the drug over a 14-week period displayed a greater overall clinical improvement and a reduction in obsessional thoughts and compulsions about using alcohol compared to those who took placebo.

Topiramate was also associated with significant improvements in liver function and reductions in plasma cholesterol, body mass index and blood pressure.

“The research shows quite clearly now that medications add to the beneficial effects of psychotherapy or psychosocial interventions,” said the study’s lead author Professor Bankole Johnson, who is chairman of the department of psychiatric medicine at the University of Virginia, US.

The use of topiramate as a treatment for alcohol dependency is currently off-label in the US and Johnson does not specifically advocate the drug over any other.

“If anyone with alcohol dependence presents to a family practitioner or a general practitioner then it’s important that medication be prescribed, whatever the medication. Otherwise they’re not getting the best effect of treatment,” he said.

He added, however, that topiramate does appear to be more powerful and efficacious than other options such as naltrexone or acamprosate.

The double-blind trial, published in The Archives of Internal Medicine, involved 317 alcohol-dependent patients aged from 18 to 65.

Patients in the topiramate group also reported improvements in some aspects of quality of life such as leisure-time activities and household duties, and displayed a trend towards reduced sleep disturbances. However adverse events – including pins and needles, headache, fatigue, nausea and anorexia – were more common among these patients than those who took placebo.

Topiramate is thought to reduce the rewarding effects of alcohol consumption by working on the corticomesolimbic system – inhibiting glutamate pathways while facilitating γ-aminobutyric acid pathways.

Previous studies had shown that the drug reduced alcohol consumption and promoted abstinence, but had not addressed the physical and psychosocial aspects of treatment.

“To have a medicine that can not only reduce the alcohol drinking but can also help improve these other problems is very important,” said Johnson, adding that topiramate can be prescribed for patients who are still drinking and not just those who are abstinent.

“And I think there’s an important public health message,” he added. “We need to find ways to treat this disease that are effective and easy to deliver because it’s number five on the World Health Organization’s global impact of disease list, and we really need treatments that all doctors can deliver and not just specialists.

“In the US we’re now getting a slight increase in the number of doctors prescribing medicine for alcohol dependence and I’m hoping that that trend will continue,” he said.

Naltrexone reduces gambling urges and behavior

Medical Tribune August 2008 P13
David Brill

The opiate antagonist naltrexone could be an effective treatment for pathological gambling (PG), according to research from the University of Minnesota.

Participants who took the drug during an 18-week randomized trial had significant reductions in gambling urges and behaviour compared to those who took placebo, and displayed improvements in overall gambling severity and psychosocial functioning.

Naltrexone, which is typically used for alcohol and opiate dependence, was well tolerated at doses of 50, 100 and 150 mg/day.

Dr. Jon Grant, lead researcher of the study, said that the findings were very encouraging.

“We were excited because although we found that there was no difference in terms of response to different doses, the medication was still significantly better than placebo,” he said.

The study supports the use of medications as a tool to treat PG, according to Grant, who hopes that naltrexone will be offered routinely for future patients. He added however that there are many different options for treating PG, and that a combination of multiple interventions is likely to be most effective.

Ms. Elda Mei-lo Chan – supervisor at the Tung Wah Group of Hospitals Even Centre in Hong Kong which treats some 700 problem gamblers each year – stressed the importance of performing a holistic assessment before deciding on the appropriate treatment for each patient.

“Gambling is a very complex problem so you really have to look at the underlying causes of the behaviour,” she said, noting that medications can be effective for those whose urges are triggered by biological or neurological factors, whereas others may gamble to boost their self esteem or as a form of protest against problems in their life.

Chan added that patients receiving drug therapy should also receive some form of psychotherapy to help them fully understand the role of the medications.

“We’ve seen too many cases who come here and expect a couple of pills to solve everything. That’s not a realistic way of dealing with the problem – they really have to have the ability to improve relationships with their families and change their lifestyle so that they can still continue their work and their normal day-to-day life,” she said.

The trial involved 77 pathological gamblers, as defined by the Diagnostic and Statistical Manual of Mental Disorders. The positive treatment effect of naltrexone reached significance after 6 weeks. [J Clin Psychiatry 2008 Epub ahead of print]

Prior to enrollment, participants gambled for an average of 13.1 hours and lost US$535.54 per week. Having money was reported as the most common trigger for gambling urges, followed by stress, loneliness and advertisements.

Gambling behaviour and urges were assessed using a range of diagnostic tools, including the Yale-Brown Obsessive Compulsive Scale. Patients who improved during the trial said that they felt greater control over their actions and less of an impulse to act immediately on their urges, Grant said.

The study replicates and extends the results of previous studies into naltrexone for PG, carried out by the same group.