New research clarifies how trauma in early life can lead to obesity in adolescence. In a study of 160 young people between the ages of 9 and 15, researcher Janitza Montalvo-Ortiz and colleagues identified seven sites in the genome where DNA methylation predicted body mass index (BMI) in adolescence. The researchers also collected information on family traumas that occurred during the participants’ childhoods and found that DNA methylation and family trauma such as child abuse interacted to predict BMI.
Epigenetics describes the ways life experiences can change how easily DNA is turned on or off. While the genes coded by DNA sequences one inherits from one’s parents never change, the structure of DNA can change. DNA methylation is one type of epigenetic change that refers to the addition of methyl groups to promoter regions of DNA in response to life events.
In this research, which was presented at the 2016 meeting of the Society of Biological Psychiatry, Montalvo-Ortiz and colleagues found that the site of DNA methylation with the strongest link to BMI in adolescence was a gene called MAP2K3. This gene had previously been linked to obesity, but this is the first time DNA methylation at this site has been linked to both obesity and childhood trauma. Other relevant gene sites where DNA methylation occurred include ANKRD2, CPXM2, NUBPL, and RFK.
A 2016 study by researcher David Arterburn and colleagues in the Journal of Clinical Medicine suggests that taking an antidepressant for two years is associated with an increase in body weight. Luckily, bupropion (trade name Wellbutrin) is an exception that may be a good choice for obese or overweight patients.
The researchers analyzed links between which antidepressants patients in a large health system in Washington State were prescribed and their body weight two years later.
The researchers used fluoxetine (Prozac) as a reference. Most antidepressants did not differ significantly from fluoxetine in terms of the weight gain experienced by people taking the drug.
There were a few exceptions. Compared to non-smoking fluoxetine users, who gained an average of 4.6 pounds in two years, non-smoking bupropion users actually lost weight—an average of 2.4 pounds. (Smokers taking bupropion still gained an average of 6.9 pounds.)
Sertraline (Zoloft) was another exception. Sertraline users gained more than users of other antidepressants—an average of 10.5 pounds over two years.
Smoking, alcohol use, obesity, and diabetes aren’t just harmful to the body. They may actually lead to dementia.
Behavioral risk factors for cardiovascular disease like those listed above have been linked to reduced volume in the brain as a whole and several brain regions, including the hippocampus, precuneous, and posterior cingulate cortex. A 2015 study by researcher Kevin King and colleagues found that these reduced brain volumes are early indicators of cognitive decline.
King and colleagues analyzed data on 1,629 participants in the long-term Dallas Heart Study. Their cardiovascular risk factors were assessed when they began the study, and their brain volume and cognitive function were measured seven years later.
Alcohol use and diabetes were associated with lower total brain volumes, while smoking and obesity were linked to low volumes in the posterior cingulate cortex.
Low hippocampal volume was linked to past alcohol use and smoking, while lower precuneous volume was linked to alcohol use, obesity, and blood glucose levels.King and colleagues suggested that subtle differences in brain volumes in midlife are the first sign of developing dementia in participants who were still younger than 50 years of age.
Liraglutide is taken as a daily injection and is meant to be used alongside a calorie-reduced diet and increased physical activity. Liraglutide works by mimicking a peptide (GLP-1) that regulates appetite and calorie intake.
Recommended dosage is 3 mg/day, but should begin at 0.6 mg/day for the first week and gradually increase by 0.6mg each week to reduce the likelihood of gastrointestinal side effects.
In three clinical trials, participants who were overweight or obese, some of whom had weight-related conditions such as high blood pressure, type 2 diabetes, or high cholesterol, either received training about following a reduced-calorie diet and increasing physical activity or had already lost up to 5% of their body weight by engaging in these practices.
Among those participants who did not have diabetes or a weight-related condition, 62% lost up to 5% of their body weight after a year of taking liraglutide, compared to 34% of those who were given a placebo injection.
Of the participants who had type 2 diabetes, 49% lost up to 5% of their body weight after a year of liraglutide, compared to 16% of those who received placebo.
Of those who had a weight-related condition other than diabetes, 42% lost up to 5% of their body weight compared to 21.7% who took placebo.
A 2015 study by Rene L. Olvera and colleagues in the Journal of Clinical Psychiatry indicated that among 1,768 Mexican-Americans living along the border from 2004–2010, 30% were currently depressed, 14% had severe depression, and 52% were obese. Women were more likely to be depressed, and more likely to have severe depression. Other factors making depression more likely included low education, obesity, low levels of “good” cholesterol, and larger waist circumference. Low education and extreme obesity were also linked to severe depression.
In a commentary on the article in the same issue, researcher Susan L. McElroy wrote that “the medical field needs to firmly accept that obesity is a risk factor for depression and, conversely, that depression is a risk factor of obesity.” She suggested that people with obesity, those who carry excess weight around their middles, and those who have related metabolic symptoms such as poor cholesterol should all be evaluated for depression. Likewise, those with depression should have their weight and body measures monitored. People with both obesity and depression should be evaluated for disordered eating.
In a talk at the 2015 meeting of the International Society for Bipolar Disorder, researcher David Bond reported that 75% of patients in a study of first episode mania had unhealthy body mass indices (BMIs). Forty percent were overweight while thirty-five percent were obese. Higher weight was associated with greater illness severity. Bond said that in other studies obesity has been associated with less time well and a greater risk of relapse into depression.
Obese patients also had lower brain volume, worse memory, and a greater risk of developing early onset dementia compared to other patients. Those who were overweight or obese had a 35% higher risk of developing Alzheimer’s disease.
In a different talk at the same meeting, researcher Roger McIntyre reported that among patients with bipolar disorder, those who were obese have greater cognitive problems and more evidence of inflammation than those who were not obese. He has seen indirect antidepressant effects and other health benefits following weight loss from bariatric surgery.
Liraglutide, an injectable drug used to treat Type 2 diabetes, has been approved by the Federal Drug Administration for the treatment of obesity. The drug is newly formulated in recommended doses of 3mg/day under the brand name Saxenda. Liraglutide is suggested for adults with a body mass of 30 or above, or 27 and above with other weight-related conditions such as hypertension, diabetes, or high cholesterol.
In clinical trials, out of 3,731 participants without weight-related comorbid conditions, 62% of those who received liraglutide lost at least 5% of their body weight, compared to 34% of those who received placebo. Of the 635 participants with Type 2 diabetes, 49% of those who received liraglutide lost at least 5% of their body weight, compared to 16% of those who received placebo. In the 422 participants with other weight-related comorbidities, 42% of those taking liraglutide lost 5% or more of their body weight compared to 21.7% of those on placebo.
There were also some improvements in risk factors for cardiovascular disease in people taking liraglutide.
Liraglutide affects appetite regulation, leading to reduced calorie intake that produces weight loss. The treatment is delivered in a pre-filled multidose pen that can be injected in the abdomen, thigh, or arm. Dosing begins at 0.6 mg/day to minimize unwanted gastrointestinal effects.
Omega-3 fatty acids are found in some green vegetables, vegetable oils, and fatty fish. There is some evidence that omega-3 fatty acid supplements can reduce depression, but researchers are trying to clarify which omega-3s are most helpful, and for whom. A new study in Molecular Psychiatry suggests that depressed people with higher inflammation may respond best to EPA omega-3 fatty acids compared to DHA omega-3 fatty acids or placebo. Researchers led by M.H. Rapaport divided people with major depressive disorder into “high” and “low” inflammation groups based on their levels of the inflammatory markers IL-1ra, IL-6, high-sensitivity C-reactive protein, leptin, and adiponectin. Participants were randomized to receive eight weeks of treatment with EPA omega-3 supplements (1060mg/day), DHA omega-3 supplements (900mg/day), or placebo.
While overall treatment differences among the three groups as a whole were negligible, the high inflammation group improved more on EPA than on placebo or DHA, and more on placebo than on DHA. The authors suggest that EPA supplementation may help relieve symptoms of depression in people whose depression is associated with high inflammation levels, a link common among obese people with depression.
Editor’s Note: These data add to a study by Rudolph Uher et al. in which people with high levels of C-reactive protein responded better to the tricyclic antidepressant nortriptylene, while those with low levels of the inflammatory marker responded better to the selective serotonin reuptake inhibitor antidepressant escitalopram.
According to researcher David J. Bond at the 2014 meeting of the International Society for Bipolar Disorders, “Up to 75% of people with bipolar disorder (BD) are overweight or obese, and these patients suffer more severe psychiatric symptoms than normal-weight patients, including more frequent depressions, more suicide attempts, lower response rates to pharmacotherapy, and greater inter-episode cognitive impairment.” Obesity is a chronic inflammatory condition that damages body organs, and it appears as though the brain may be one of these. Adipose (fatty) tissue is an endocrine organ that produces substances that cause inflammation in blood vessels and that damage the heart.
Obesity is associated with decreased total brain volume, and in children, decreased gray matter volume. Obesity increases the risk of cognitive impairment, and decreases memory, attention, and executive functioning. Obesity increases the risk of Alzheimer’s disease, as well as multiple sclerosis, Parkinson’s, and depression.
In bipolar disorder, obesity decreases response to mood stabilizers and atypical antipsychotics. Bond found that in patients with a first episode of mania, body mass index (BMI) was inversely related to white matter volume and temporal lobe gray matter volume. Higher BMIs also led to neurochemical changes including increased hippocampal glutamate and reduced N-acetylaspartate. Bond also noted findings by Roger S. McIntyre that weight loss surgery in patients with bipolar disorder led to more positive treatment outcomes.
Editor’s Note: These findings speak to the importance of exercise and good diet, using medications with the least likelihood of weight gain, and treating obesity once it has developed. We have previously noted the weight loss effects of topiramate and zonisamide, and new data support the substantial weight loss with the combination of bupropion (150-300mg) and naltrexone (50mg).
The combination of antidepressant bupropion (Wellbutrin) and naltrexone (Revia), a drug that helps alcoholics resist the craving for alcohol, can help patients keep their weight down. Last year we summarized an article by Smith et al. in the journal Diabetes, Obesity, and Metabolism that showed that obese patients with diabetes treated with the combination of bupropion and naltrexone had excellent weight loss and reduction in body fat compared to those treated with either drug alone or with placebo.
A more recent study by G. J. Wang et al. published in the International Journal of Obesity in 2013 shows that the combination of 360mg of bupropion sustained release and 32mg of naltrexone sustained release works by reducing patients’ response to food cues. Forty women were shown a video of their favorite food being prepared, which stimulated parts of the brain associated with visual stimuli and other functions. Those who received the combination of naltrexone and bupropion had lessened hypothalamic response to the videos compared to those who received placebo, and also showed activity in parts of the brain associated with inhibitory control (the anterior cingulate), internal awareness (the superior frontal cortex, the insula, and the superior parietal cortex), and memory (the hippocampus).
Editor’s Note: It looks like the drug combination prompts the brain to say, “Wow, that looks good, but maybe I shouldn’t take in any more calories today.”