December 9, 2009 — Young adults with higher blood lead levels are more likely to have major depressive disorder (MDD) or panic disorder, even if they have exposure to lead levels generally considered safe, new research suggests.

Maryse F. Bouchard, PhD, Universite de Montreal, Quebec, Canada, and Harvard School of Public Health, Boston, Massachusetts, and colleagues found individuals with lead levels of 2.11 μg/dL or more had 2.3 times the odds of having MDD and nearly 5 times the odds of panic disorder compared with those with lead levels of 0.7 μg/dL or less.

“What is most surprising is the finding that lead can be associated with adverse mental health status at such low levels of exposure,” Dr. Bouchard told Medscape Psychiatry. The mean blood level in study subjects was 1.61 μg/dL.

The study is published in the December issue of Archives of General Psychiatry.

The investigators analyzed data from 1987 adults aged 20 to 39 years who were participants in the National Health and Nutrition Examination Survey between 1999 and 2004. Participants underwent medical examinations that included collection of a blood sample and also completed a diagnostic interview to identify MDD, panic disorder, and generalized anxiety disorder.

The number of individuals who met diagnostic criteria for MDD was 134 (6.7%), 44 (2.2%) had panic disorder, and 47 (2.4%) had generalized anxiety disorder.

Because smoking is related to blood lead levels, the researchers conducted additional analyses excluding the 628 smokers. Among nonsmokers, the elevation in risk between the highest and lowest blood lead levels was increased to 2.5-fold for MDD and 8.2-fold for panic disorder.

Need to Reduce Environmental Exposure

Previous studies conducted in highly exposed employees from foundries, smelters, and battery plants show that these workers (who had blood lead levels averaging 40 μg/dL) have reported elevated symptoms of depression, hostility, and anxiety, said Dr. Bouchard.

A study conducted in nonoccupationally exposed older men showed that those with higher blood lead levels (averaging 6.3 μg/dL) also had a higher prevalence of self-reported anxiety, phobic anxiety, and depression. “In my study group, the mean blood lead level was only 1.6 μg/dL, which is representative of the exposure level in the general population,” Dr. Bouchard said.

Eliminating lead from gasoline has decreased average blood lead levels in the general population, but remaining sources of exposure include paint, industrial processes, pottery, and contaminated water.

However, Dr. Bouchard pointed out that blood lead levels reflect not only current exposure but also past exposures because lead is sequestered in bones and is slowly released into the blood.

“These findings suggest that lead neurotoxicity may contribute to adverse mental health outcomes, even at levels generally considered to pose low, or no, risk,” the researchers conclude. “These findings, combined with recent reports of adverse behavioral outcomes in children with similarly low blood lead levels, should underscore the need for considering ways to further reduce environmental lead exposures,” they write.

Dose-Response Relationship Questioned

Edwin van Wijngaarden, PhD, interim chief of the Division of Epidemiology, Community & Preventive Medicine at the University of Rochester in New York, reviewed the study for Medscape.

“Although the data reported by Bouchard et al are certainly suggestive of an association between blood lead levels and major depressive disorder, the nature of the dose-response relationship is somewhat uncertain, with no clear pattern until the upper quintile.

“The authors emphasize the statistically significant trend statistics, which are appropriate if there is a true linear trend — not sure if that is the case here. The results for panic disorder and generalized anxiety disorder suffer from limited statistical power and consequently statistically imprecise risk estimates, and I would be cautious interpreting the dose-response patterns reported for these outcomes,” he said.

Dr. van Wijngaarden also noted that the mental health outcomes studied were only available for adults aged 20 to 39 years and might differ for older adults with higher levels of cumulative lead exposure.

Dr. van Wijngaarden and colleagues recently examined population-based data on blood lead levels in relation to depression in the United States in a study that will be published in the near future.

This study was supported by the Canadian Institutes for Health Research and the National Institute of Environmental Health Sciences. Dr. Bouchard and Dr. van Wijngaarden have disclosed no relevant financial relationships.

Arch Gen Psychiatry. 2009;66:1313-1319.

Regards,

Linda

November 3, 2009 (Honolulu, Hawaii) – Overall nutritional status in children with attention deficit hyperactivity disorder (ADHD) shows that this patient population is at risk for low trace mineral status, including deficiencies in zinc and copper – minerals that may play a crucial role in the production of dopamine, norepinephrine, and melatonin, which regulates sleep.

Presented here at the American Academy of Child & Adolescent Psychiatry 56th Annual Meeting, a study conducted by investigators at the University of British Columbia and the Children’s and Women’s Health Centre in Vancouver, Canada, showed among 44 children aged 6 to 12 years with ADHD, rates of zinc and copper deficiency were 45% and 35%, respectively.

Dr. Margaret Weiss

“There are a lot of studies in ADHD children looking at sugar intake, etcetera, but no one has ever actually looked at the dietary intake and subsequent nutrients of children with ADHD, ” principal investigator Margaret Weiss, MD, PhD, told Medscape Psychiatry.

With first author Joy Kiddie, RD, the study included 44 drug-naive and drug-treated ADHD children aged 6 to 12 years. Of these children, 17 were medication-naive, 18 were taking stimulant medications, and 9 were taking atomoxetine.

The children’s dietary intake was assessed using a 3-day food record and 24-hour recall. The food record assessed macronutrient/micronutrient intake relative to the recommended dietary allowances and food group recommendations.

The 24-hour recall was used to assess the percentage of low-nutrient density foods, or so-called “junk food” intake.

The study revealed that serum zinc below laboratory norms was present in 77% of children aged 6 to 9 years and 67% of children aged 10 to 12 years, and 25% of the children were below the cutoffs for zinc deficiency. Serum copper below laboratory norms was present in 23% of children.

No Difference in Junk Food Consumption

The investigators found that the study sample consumed comparable levels of protein, carbohydrate, and fat compared with recommendations and population norms, and ADHD children were no different than population norms in intake of low-nutrient density foods. However, 40% of the children consumed less than the recommended levels of meat and meat alternatives and had low levels of related micronutrients that are essential cofactors for the body’s manufacture of dopamine, norepinephrine, and melatonin.

Measurement of blood levels of micronutrients replicated previous findings of zinc deficiency and demonstrated copper deficiency for the first time. In addition, a majority of children had serum ferritin levels lower than 50 μg/mL, a level considered necessary for entry into the central nervous system.

“There is a commonly held belief that children with ADHD eat more junk food than other children, but the study did not confirm this view,” said Dr. Weiss. “However, our data suggest children with ADHD are nutritionally different from the rest of the population in that they eat less meat, fish, and poultry and have low levels of related micronutrients that are essential cofactors for the body’s manufacture of dopamine norephinephrine, and melatonin.”

Need to Focus on Nutrition

In a separate study of zinc supplementation also presented here at the American Academy of Child & Adolescent Psychiatry 56th Annual Meeting, Eugene Arnold, MD, and colleagues from The Ohio State University, Columbus, found that supplementation with 15 or 30 mg of elemental zinc made no difference to symptoms compared with placebo in a group of children diagnosed with ADHD after 13 weeks of treatment.

This study, said Dr. Weiss, raises many questions because previous research has suggested that zinc supplementation does make a difference. “It may not just be a question of what children eat but also whether they can absorb or metabolize zinc, or whether they are excreting it. In other words, is there some kind of phenomenon of zinc wasting?” she said.

Dr. Weiss said that, based on this study, it is too early to make any clinical recommendations beyond ensuring that children with ADHD have an adequate diet that includes appropriate levels of fish, meat, and poultry. However, she acknowledged, this can be a challenge in children on stimulant medications because of the drugs’ appetite-suppressing effect.

She added that it is important that clinicians with expertise in the assessment of nutritional status provide parents with information about good nutrition. “Traditionally, the emphasis on ADHD has been on treating the core symptoms of the disorder, but it is also important to assess and manage basic issues of health such as sleep, nutrition, and growth. Good health makes a difference,” said Dr. Weiss.

Dr. Weiss has disclosed that she is on the advisory board of and/or has received research or grant support from Eli Lilly and Company, Janssen, Purdue University, Shire Pharmaceuticals Inc, and Takeda Pharmaceuticals North America, Inc.

American Academy of Child & Adolescent Psychiatry 56th Annual Meeting: Abstract 17.3. Presented October 31, 2009.

A large new study confirms that people with severe mental disorders – such as schizophrenia or other psychotic disorders – are 25 percent to 40 percent more prone to die from heart disease than people without mental illness are.

Moreover, smoking and physical inactivity – behaviors that individuals potentially can change – significantly contribute to this increased risk of death, found researchers led by Amy Kilbourne, Ph.D.

They looked at results from the 1999 Large Health Survey of Veteran Enrollees in conjunction with the VA’s National Psychosis Registry and the National Death Index of the Centers for Disease Control and Prevention (CDC). Including responses from more than 147,000 veterans, the study is the largest of its kind to ever take place. Most of the respondents were men and about two-thirds were 50 or older.

Kilbourne, associate director of the VA Ann Arbor National Serious Mental Illness Treatment Research and Evaluation Center in Michigan, and colleagues from Dartmouth Medical School conducted the study, which appears in the November-December issue of the journal General Hospital Psychiatry.

Patients with mental disorders who also had a diagnosis of diabetes – a known risk factor for heart disease and a side effect of some antipsychotic medications – were at high risk for heart disease-related mortality, as were patients with a diagnosis of dementia.

Smoking and lack of exercise, both common behaviors in people with mental disorders, contributed to the heart disease-related deaths considerably.

“These are devastating illnesses that lead to a lot of functional impairment, so many of these individuals have difficulty staying motivated to exercise to begin with, or finding places where they feel comfortable exercising,” Kilbourne said.

However, even when considering factors such as diabetes and lifestyle, researchers found that patients with schizophrenia or other psychotic disorders were still more likely to die from heart disease. “This suggests that we are either missing some factor, or there is something inherent about having these disorders that puts patients at greater risk for heart disease-related mortality,” Kilbourne said.

Eric Goplerud, Ph.D., director of the Center for Integrated Behavioral Health Policy in Washington, said that results of this study and others suggest that people with serious mental illnesses are far less likely to receive medical screening and general preventive care. He said that lack of coordinated care has serious consequences: “Serving their mental needs in one stovepipe and their medical needs in another is probably associated with premature mortality.”

“The issue of cardiovascular disease in this population is huge,” Goplerud said. “As we look at national health reform, it is absolutely critical that people with mental illness and addictions be included – they are dying of preventable medical conditions.”

General Hospital Psychiatry is a peer-reviewed research journal published bimonthly by Elsevier Science. For information about the journal, contact Wayne Katon, M.D., at (206) 543-7177.

Kilbourne AM, et al. Excess heart-disease-related mortality in a national study of patients with mental disorders: identifying modifiable risk factors. Gen Hosp Psychiatry 31(6), 2009.

Source
Health Behavior News Service