Tuesday, February 19, 2013

Scientific Update: Exercise, Mood, and Bipolar Disorder

Exercise is well-known to influence both physical and mental health. The articles reviewed in this post are specific to the impact of exercise on mental health and the symptoms of bipolar disorder. These articles show that people living with bipolar disorder are more likely to be overweight and to have poor eating habits. The implications of these studies is that people living with bipolar disorder must develop good eating habits and a routing habit of physical activity.

Kilbourne, Amy M., Dana L. Rofey, John F. McCarthy, Edward P. Post, Deborah Welsh, and Frederic C. Blow. 2007. "Nutrition and exercise behavior among patients with bipolar disorder." Bipolar Disorders 9, no. 5: 443-452.

Objectives: There have been few comprehensive studies of nutrition and exercise behaviors among patients with bipolar disorder (BPD). Based on a national sample of patients receiving care in the Veterans Affairs (VA) health care system, we compared nutrition and exercise behaviors among individuals diagnosed with BPD, others diagnosed with schizophrenia, and others who did not receive diagnoses of serious mental illness (SMI). Methods: A cross-sectional study of patients who completed the VA's Large Health Survey of Veteran Enrollees section on health and nutrition in fiscal year (FY) 1999 and who either received a diagnosis of BPD (n = 2,032) or schizophrenia (n = 1,895), or were included in a random sample of non-SMI VA patients (n = 3,065). The groups were compared about nutrition and exercise behaviors Results: Patients with BPD were more likely to report poor exercise habits, including infrequent walking or strength exercises than those with no SMI. They were also more likely to self-report suboptimal eating behaviors, including having fewer than two daily meals. 

Piri, Mohsen, Shirin Zardoshtian, Shahrzad Khazaee, and Roghieh Piri. 2012. "The Effect of Eight Weeks of Aerobic Training on Reducing Mood Disorders, Depression And Mania in High School Students High School Boys." International Journal Of Academic Research In Business & Social Sciences 2, no. 1: 267-273.

Abstract: The aim of this study was to consider the effect of eight weeks of aerobic training on the reduction of mood disorders, depression and mania in boys' high school in Ilam-Iran. This was a quasi-experimental and field research taking the experimental and control groups into consideration. In this study, 60 students were randomly selected as the sample. In order to measure students' Depression and mania, multifaceted Minnesota questionnaire (MMPI-2) and depression and mania sub-scales were used. We applied both descriptive and inferential statistics using SPSS software for statistical analysis of data. The results showed that eight weeks of aerobic exercise had a significant effect on students` depressive disorders and mania. Eight weeks of aerobic exercise reduced depression and mania in experimental group of students. [Edited from the abstract written by the author]

Eriksson, Sebastian, and Gunvor Gard. 2011. "Physical exercise and depression." Physical Therapy Reviews 16, no. 4: 261-268.
Objectives: The objective was to review studies which used physical exercise as an intervention to treat major depression, focusing on methodology, mechanisms of action, types of physical exercise and treatment outcomes. Methods: A literature review from PsycInfo and PubMed databases from 2000-2010 using the key words 'major depression', 'exercise', 'outcome', 'physical activity' and 'aerobic training' as search terms. Results: Eight studies met the inclusion criteria. Seven of the eight studies showed significantly improved mood and reduced depression. Three studies measured an increase in aerobic capacity, two with correlated mood improvements. One showed a correlation between increased muscle strength and reduced feelings of depression. ConclusionPhysical exercise can be an effective treatment against depression. A mood enhancing effect of exercise was identified in the interventions regardless of the mechanism of action.  [Edited from the abstract from the author]

Saturday, February 16, 2013

Bipolar Medications and Grapefruit & Citrus Juices

Although citrus juices including grapefruit juice are very good for you with their high levels of vitamin C and other nutrients, they have been known to have negative interactions with certain medications and some medications taken for bipolar disorder are included on that list. 
Certain nutrients within this family of fruits interact with medications that treat bipolar disorder (such as olanzapine) and this must be taken into consideration when deciding what fruit juice to drink. Olanzapine comes with a warning associated with the ingestion of grapefruits or grapefruit juice while on the medication because it impacts the way the body processes the active ingredient in the medication. Grapefruit juice has been known to impact the uptake (the rate of absorption) of certain substances and/or the bioavailability (how much is available to the body) of others.
Some researchers suggest that the pharmacokinetics (or intereactions) with medications is very complex and in one literature review almost 200 studies were found that studied grapefruit juice interaction and interactions were published for 40 drugs (Saito, Hirata-Koizumi, & Matsumoto et al, 2005). Another study found that due to the complexity involved in measuring intake and magnitude of interactions it was challenging to predict the extent of grapefruit product-drug interactions (Seden, Dickinson, Khoo, & Back, 2010). 
Some people with bipolar disorder  take hormone substitutes such as levothyroxine due to thyroid dysfunction, which can be a side-effect of lithium. It appears that although there is some effect of grapefruit juice on absorption of the hormone it does not impact the availability of the hormone to the endocrine system (Lilja, Laintinen & Neuvonen, 2005).
These articles and the warning labels on some medications would suggest that people taking medications for mental illness should avoid grapefruits until science can give firm recommendations. To be safe it is best to read the documentation that comes with your medication, especially the sections that describe possible interactions and side-effects. Discuss with your medical provider any risk of citrus/grapefruit interactions with any medications you are taking.

Lilja, J. L., Laintine, K., & Neuvonen, P. J. (2005). Effects of grapefruit juice on the absorption of levothyroxine. British Journal of Pharmacology, 60(3), 337-341
Saito, M., Hirata_Koizumi, M., Matsumoto, M, Urano, T., & Hasegawa, R. (2005). Undesirable effects of citrus juice on the pharmacokinetics of drugs: focus on recent studies. Drug safety: an international journal of medical toxicology and drug experience 28(8): 677-694.
Seden, K., Dickinson, L., Khoo, S., & Back, D. (2010). Grapefruit-drug interactions. Drugs, 70(18): 2373-2407.

Sunday, February 3, 2013

Circadian Rhythms and Bipolar Disorder: Scientific Update

It has been some time since I wrote a post on scientific research, which was to be the focus of this blog but I expanded it into many things bipolar while staying on the science side. This post is one way to indulge my hypergraphia.

In selecting articles to review for this blogpost, I first find articles I understand as many neuroscience articles can be highly technical. Second, I find articles that have some practical utility to people living with bipolar disorder. So I tend to avoid articles that are related to mice or other animals. 

The first article is about the circadian rhythms. According to the National Institute of General Medical Sciences (NIGMS), which is a part of the National Institutes of Health (NIH), circadian rhythms are the physical, mental and behavioural patterns that closely follow a 24 hour cycle. These patterns are found in most living things including animals, plants and even microbes. Chronobiology is the study of circadian rhythms. Produced by natural factors in the body, circadian rhythms are also affected by factors in the environment with light being the most important as it controls the genetic switches that influence these patterns. Circadian rhythms influence many bodily functions such as body temperature, hormone releases and sleep/wake patterns. 

Circadian rhythm characteristics in mood disorders: Comparison among bipolar I disorderbipolar II disorder and recurrent major depressive disorderChung, JK, Lee, KY, Kim, SH et al. (012) Clinical Psychopharmacology and Neuroscience, Vol 10(2), Aug, 2012. pp. 110-116.

Summary of Findings
This Korea-based study used factor analysis to study data on how people experience the rhythms of day and night and found that people with mood disorders were more likely to be evening types than people with no mood disorders. Those with bipolar disorder I were more likely to have evening tiredness than those with bipolar disorder II. Those with bipolar I scored higher for morning alertness than people with recurrent major depressive disorder (RMDD).

The second article is highly technical and the practical implications are not as explicit but the findings are worth a mention because they reinforce the link between abnormal circadian rhythm patterns and bipolar disorder.

A survey of genetic studies supports association of circadian clock genes with bipolar disorder spectrum illnesses and lithium response. McCarthy, MJ, Nievergelt, CM, Kelsoe, JR, & Welsh, DK. (2012), PLoS ONE, 7(2) 

Summary of Findings
This study acknowledges the relationship between abnormal circadian rhythms and bipolar spectrum disorders and that this has inspired the search for genetic sources for this abnormality. However, to date there have been no significant findings from this research that would link genes to these abnormalities. The researchers list 3 factors that could be a reason for this lack of significant findings: 1. complex traits usually involve more than one gene; 2. circadian rhythms may be more complicated than they first appeared; and, 3. genetic risk for bipolar disorder could be spread among many illnesses. Without going into technical detail, the major finding was that their analysis revealed previously unrecognized links between bipolar disorder and circadian rhythms.

Circadian rhythms and bipolar disorder. Murray, G. (2010). Bipolar Disorders, 12(5), 459-472

Summary of Findings

This accessible article is a review of existing literature on the relationship between abnormal circadian rhythms and bipolar disorder. It does not present anything particularly new but does reinforce what is already known.