Journal Digest

A study published in PNAS has found that giving the antidepressant fluoxetine to developing zebrafish reduces levels of the stress hormone cortisol not only in the recipient fish, but also in three subsequent generations.

Researchers at the University of Ottawa and colleagues exposed newly fertilized zebrafish eggs to either low (0.54 ug/L) or high (54 ug/L) levels of fluoxetine for six days. These values reflect what has been detected in contaminated water (low) and the umbilical cord blood of women taking fluoxetine (high). A third group of control fish was not exposed to any fluoxetine.

The researchers found that the fish exposed to high and low levels of fluoxetine both had lower levels of cortisol compared with fish not exposed to the medication; the same was true of three subsequent generations of the exposed fish. Cortisol reduction was more pronounced in the high-fluoxetine lineage, and more pronounced in males compared with females at either concentration. The degree of cortisol reduction did not significantly diminish across generations, despite no further drug exposure.

Male fish in the first and second generation of the high-fluoxetine lineage also displayed less movement and exploration when introduced to new environments, suggesting a behavioral consequence to fluoxetine exposure. There were no significant behavioral differences in female fish or males in the low-exposure group.

“Given this evidence of the transgenerational effects of developmental FLX [fluoxetine] exposure on the stress axis and behavioral response, it would be appropriate to determine whether these effects occur in humans because FLX is generally the first line of pharmacological treatment in pregnant women suffering from affective disorders,” the authors wrote.

People who take the antidiabetic drug liraglutide daily and participate in intensive behavioral therapy (IBT) may experience more significant weight loss than those who participate in IBT only, according to a study published in the journal Obesity. IBT involves lifestyle counseling sessions aimed at changing diet and exercise.

Researchers at the University of Pennsylvania randomly assigned 150 obese adults (BMI of 30 to 55) to receive 21 sessions of IBT alone, IBT plus liraglutide (3 mg/daily), or IBT plus liraglutide and a low-calorie diet regimen (which included prepared frozen entrees and diet shakes). The study lasted one year, and IBT sessions were provided weekly for the first four weeks, biweekly for the next 20 weeks, and then every four weeks over the remaining 28 weeks.

After one year, the average weight loss in the IBT, IBT-liraglutide, and IBT-liraglutide-diet groups was 6.1 percent, 11.5 percent, and 11.8 percent, respectively. The number of participants who lost at least 5 percent of their initial body weight was 44 percent, 70 percent, and 74 percent for the IBT, IBT-liraglutide, and IBT-liraglutide-diet groups, respectively. In all three groups, greater attendance at IBT sessions correlated with greater weight loss.

Weight loss in all three groups was also associated with clinically meaningful improvements in blood pressure, cholesterol levels, and depressive symptoms.

The antidepressant trazodone is no safer than atypical antipsychotics when it comes to increasing the risk of falls in older patients with dementia, reports a study published in CMAJ.

Researchers at the University of Toronto compared the health outcomes of 9,463 adults (aged 66 and older) with dementia living in long-term care facilities who were prescribed either trazodone or an atypical antipsychotic (olanzapine, quetiapine, or risperidone). A total of 6,588 seniors received trazodone and 2,875 received an antipsychotic. These patients were tracked for 90 days.

The researchers found no statistical differences between patients receiving trazodone or antipsychotics in the risk of a major bone fracture (hip, pelvis, or arm) or a severe fall (requiring an emergency department visit) within 90 days of starting medication. In contrast, patients taking trazodone were found to be 25 percent less likely to die within the 90-day follow-up period.

“Although both trazodone and atypical antipsychotics have been associated with an increased risk of falls and fractures, antipsychotic use has also been associated with an increased risk of myocardial infarction and stroke in patients with dementia,” the authors noted.

Combing through the genetic data of over 55,000 people, researchers have for the first time identified genetic risk factors for attention-deficit/hyperactivity disorder (ADHD). The findings were published in Nature Genetics.

Members of the multinational Psychiatric Genomics Consortium analyzed DNA sequences of 20,183 people with ADHD and 35,191 people without ADHD from study populations in China, Europe, and North America. They identified genetic variants at 12 regions strongly associated with ADHD risk.

The 12 genetic loci identified were all near genes considered to be important for neurodevelopment in mammals, including FOXP2, which is considered a critical gene in the development of human language.

Additional analysis revealed that people with a greater number of ADHD risk variants were more likely to have had children at a younger age and have more children. Smoking and obesity were also associated with having more ADHD risk variants.

“Shared genetic risk with health risk behaviors may … reflect an impaired ability to self-regulate and inhibit impulsive behavior,” the investigators wrote.

While the use of telemedicine for the treatment of substance use disorders (SUD) has been rising, this tool remains greatly underused, according to a study in Health Affairs.

Researchers at Harvard Medical School and the RAND Corporation analyzed insurance claims data from 2010 to 2017 to assess patterns of telemedicine use for SUD and how this use compared with the use of telemedicine overall.

The analysis showed that the use of telemedicine for SUD has been growing: from 0.62 visits per 1,000 SUD diagnoses in 2010 to 3.05 visits per 1,000 SUD diagnoses in 2017. Despite this increase in prevalence, telemedicine visits for SUD represented just 0.1 percent of all SUD-related visits, and just 1.4 percent of all telemedicine visits for any condition.

Although per capita rates of telemedicine for SUD were higher among rural residents, most people receiving the care were in urban areas, the study found.

Additionally, telemedicine for SUD was primarily being used to complement in-person care rather than as a standalone treatment.

“The low rates of telehealth visits for substance use disorder that we found represent a missed opportunity to get people the help they need, especially in the context of the ongoing opioid epidemic,” lead author Haiden Huskamp, Ph.D., of Harvard said in a press release.