Oxidative stress may be a common mechanism linking major depression and osteoporosis

Exploring the pathophysiological influence of heme oxygenase-1 on neuroinflammation and depression: A study of phytotherapeutic-based modulation

BACKGROUND

The heme oxygenase (HO) system plays a significant role in neuroprotection and reduction of neuroinflammation and neurodegeneration. The system, via isoforms HO-1 and HO-2, regulates cellular redox balance. HO-1, an antioxidant defense enzyme, is highlighted due to its association with depression, characterized by heightened neuroinflammation and impaired oxidative stress responses.

METHODOLOGY

We observed the pathophysiology of HO-1 and phytochemicals as its modulator. We explored Science Direct, Scopus, and PubMed for a comprehensive literature review. Bibliometric and temporal trend analysis were done using VOSviewer.

RESULTS

Several phytochemicals can potentially alleviate neuroinflammation and oxidative stress-induced depressive symptoms. These effects result from inhibiting the MAPK and NK-κB pathways - both implicated in the overproduction of pro-inflammatory factors - and from the upregulation of HO-1 expression mediated by Nrf2. Bibliometric and temporal trend analysis further validates these associations.

CONCLUSION

In summary, our findings suggest that antidepressant agents can mitigate neuroinflammation and depressive disorder pathogenesis via the upregulation of HO-1 expression. These agents suppress pro-inflammatory mediators and depressive-like symptoms, demonstrating that HO-1 plays a significant role in the neuroinflammatory process and the development of depression.

Depressive symptomology and cancer incidence in men and women: Longitudinal evidence from the HUNT study

BACKGROUND

Depressive symptoms and mood disorders are associated with a host of physical conditions. However, it is inconclusive whether depressive symptoms are also associated with cancer onset. The aim of this study was to investigate whether depressive symptoms are associated with cancer incidence in a large population-based sample of men and women.

METHODS

This study examined data from waves two (HUNT 2, 1995-97) and three (HUNT 3, 2006-08) of the Trøndelag Health Study (HUNT). Depressive symptoms were ascertained using the Hospital Anxiety and Depression Scale (HADS-D ≥ 8), cancer onset was identified via linkage with the Cancer Registry of Norway, death records by the national Cause of Death Register (CDR), and information on lifestyle and demographic factors was self-reported. Cox-proportional hazard regression models were used to test associations. Unadjusted, age-adjusted and multivariable best models accounting for smoking, education, marital status and current employment are presented.

RESULTS

Men and women (n = 61,985; 46.0 % men) were followed from baseline over a period of 778,802 person-years. During the 20-year study period, there were 6856 (11.1 %) individuals with incident cancers and 12,480 (20.1 %) deaths (n = 2498 attributed to cancer). For men with depressive symptoms, 505 (15.3 %) developed incident cancer during the follow-up period, whereas among those without depressive symptoms, 3164 (12.5 %) developed incident cancer. Following adjustment for age, depressive symptomology was not significantly associated with risk of overall cancer onset, nor among prostate, colon or melanoma subtypes. Depressive symptoms were associated with an increased risk of bronchus and lung cancer both before (HR 1.90, 95 % CI 1.43-2.50, p ≤0.001) and after adjustment for age (HR 1.38, 95 % CI 1.04-1.80, p = 0.025). However, further adjustment for additional possible confounders explained this association. For women with depressive symptoms, 384 (11.2 %) developed incident cancer during the follow-up period, whereas among those with no depressive symptomology, 2803 (9.3 %) developed incident cancer. After accounting for age, depressive symptomology was not associated with risk of overall cancer onset, nor among breast, colon, lung and bronchus, or melanoma subtypes. Additional analyses evaluating relationship of depression symptom severity and cancer onset did not alter findings for men or women.

LIMITATIONS

This report is limited by the post-hoc study design and subsequent non-randomised nature. Future prospective studies are required.

CONCLUSION

These results suggest that depressive symptoms are not associated with an increased risk of overall or site-specific cancer onset in these men and women. Given the increased co-occurrence of other medical conditions such as cardiovascular disease, diabetes, stroke and musculoskeletal disorders in people with depression, the role of clinically diagnosed depression and other psychiatric disorders in association with cancer onset necessitates further consideration.

Associations between Bone Material Strength Index, Calcaneal Quantitative Ultrasound, and Bone Mineral Density in Men

Objectives

Impact micro-indentation (IMI) measures bone material strength index (BMSi) in vivo. This study investigated how IMI is associated with calcaneal quantitative ultrasound and bone densitometry parameters in men.

Methods

BMSi was measured on the tibial plateau using the OsteoProbe in 377 men (age 33-96 years) from the Geelong Osteoporosis Study. Broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) were assessed at the calcaneus using an ultrasonometer. Areal BMD was measured at several skeletal sites using dual-energy x-ray absorptiometry. Linear associations between parameters were tested using Pearson’s correlation. Multivariable regression techniques were used to determine associations between BMSi and other measures of bone, independent of confounders.

Results

BMSi was negatively correlated with age (r = –0.171, P = .001), weight (r = –0.100, P = .052), and body mass index (r = –0.187, P = .001), and positively with height (r = +0.109, P = .034). There was some evidence to support a positive association between BMSi and BUA (β = 0.052, P = .037), SOS (β = 0.013, P = .144), and SI (β = 0.036, P = .051). After age adjustment, this association was attenuated. No correlations were observed between BMSi and BMD at any skeletal site (r values ranged from –0.006 to +0.079, all P ≥ .13).

Conclusion

There was a small positive association between BMSi and quantitative ultrasound (QUS) parameters, which were not independent of age. No associations were detected between BMSi and BMD. This suggests that BMSi and QUS are capturing common age-dependent properties of bone. Further research on the utility of IMI alone and complementary to conventional bone testing methods for predicting fracture risk is warranted.

Health-Related Quality of Life and Medical Resource Use in Patients with Osteoporosis and Depression: A Cross-Sectional Analysis from the National Health and Nutrition Examination Survey

Background: Patients with either osteoporosis or depression are prone to develop other diseases and require more medical resources than do the general population. However, there are no studies on health-related quality of life (HRQoL) and medical resource use by osteoporosis patients with comorbid depression. We conducted this study for clarifying it. Methods: This cross-sectional study from 2005 to 2010 (6 years) analyzed 9776 National Health and Nutrition Examination Survey (NHANES) patients > 40 years old. Each patient was assigned to one of four groups: osteoporosis-positive⁽⁺⁾ and depression-positive⁽⁺⁾ (O⁺/D⁺); O⁺/D⁻; O⁻/D⁺; O⁻/D⁻. We used multivariate linear and logistic regression model to analyze the HRQoL and medical resource use between groups. Results: The O⁺/D⁺ group reported more unhealthy days of physical health, more unhealthy days of mental health, and more inactive days during a specified 30 days. The adjusted odds ratios (AORs) of O⁺/D⁺ patients who had poor general health (7.40, 95% CI = 4.80–11.40), who needed healthcare (3.25, 95% CI = 2.12–5.00), and who had been hospitalized overnight (2.71, 95% CI = 1.89–3.90) were significantly highest. Conclusions: Low HRQoL was significantly more prevalent in D⁺/O⁺ patients. We found that depression severity more significantly affected HRQoL than did osteoporosis. However, both diseases significantly increased the risk of high medical resource use.

Association of Smoking Status With Angina and Health-Related Quality of Life After Acute Myocardial Infarction

BACKGROUND

Smoking cessation after acute myocardial infarction (AMI) decreases the risk of recurrent AMI and mortality by 30% to 50%, but many patients continue to smoke. The association of smoking with angina and health-related quality of life (HRQOL) after AMI is unclear.

METHODS AND RESULTS

Patients in 2 US multicenter AMI registries (n=4003) were assessed for smoking and HRQOL at admission and 1, 6, and 12 months after AMI. Angina and HRQOL were measured with the Seattle Angina Questionnaire and Short Form-12 Physical and Mental Component Scales. At admission, 29% never had smoked, 34% were former smokers (quit before AMI), and 37% were active smokers, of whom 46% quit by 1 year (recent quitters). In hierarchical, multivariable, regression models that adjusted for sociodemographic, clinical and treatment factors, never and former smokers had similar and the best HRQOL in all domains. Recent quitters had intermediate HRQOL levels, with angina and Short Form-12 Mental Component Scale scores similar to never smokers. Persistent smokers had worse HRQOL in all domains compared with never smokers and worse Short Form-12 Mental Component Scale scores than recent quitters.

CONCLUSIONS

Smoking after AMI is associated with more angina and worse HRQOL in all domains, whereas smokers who quit after AMI have similar angina levels and mental health as never smokers. These observations may help encourage patients to stop smoking after AMI.

Neurovascular unit dysfunction with blood-brain barrier hyperpermeability contributes to major depressive disorder: a review of clinical and experimental evidence

About one-third of people with major depressive disorder (MDD) fail at least two antidepressant drug trials at 1 year. Together with clinical and experimental evidence indicating that the pathophysiology of MDD is multifactorial, this observation underscores the importance of elucidating mechanisms beyond monoaminergic dysregulation that can contribute to the genesis and persistence of MDD. Oxidative stress and neuroinflammation are mechanistically linked to the presence of neurovascular dysfunction with blood-brain barrier (BBB) hyperpermeability in selected neurological disorders, such as stroke, epilepsy, multiple sclerosis, traumatic brain injury, and Alzheimer’s disease. In contrast to other major psychiatric disorders, MDD is frequently comorbid with such neurological disorders and constitutes an independent risk factor for morbidity and mortality in disorders characterized by vascular endothelial dysfunction (cardiovascular disease and diabetes mellitus). Oxidative stress and neuroinflammation are implicated in the neurobiology of MDD. More recent evidence links neurovascular dysfunction with BBB hyperpermeability to MDD without neurological comorbidity. We review this emerging literature and present a theoretical integration between these abnormalities to those involving oxidative stress and neuroinflammation in MDD. We discuss our hypothesis that alterations in endothelial nitric oxide levels and endothelial nitric oxide synthase uncoupling are central mechanistic links in this regard. Understanding the contribution of neurovascular dysfunction with BBB hyperpermeability to the pathophysiology of MDD may help to identify novel therapeutic and preventative approaches.

Tobacco smoking predicts depression and poorer quality of life in heart disease

Background

We report on the prospective association between smoking and depression and health-related quality of life (HRQOL) in patients with coronary artery disease (CAD).

Methods

Prospective study of 193 patients with assessment of depression occurring 3-, 6- and 9- months (T1, 2, and 3, respectively) following discharge from hospital for a cardiac event. HRQOL was assessed at T3. T1 depression was assessed by clinical interview; T2 and T3 depression was assessed by self-report. Smoking at time of cardiac event was assessed by self-report. Multivariate analyses controlled for known demographic, psychosocial and clinical correlates of depression.

Results

Smoking at the time of index cardiac event increased the likelihood of being diagnosed with Major Depressive Disorder (MDD) at T1 by 4.30 [95% CI, 1.12-16.46; p < .05]. The likelihood of receiving a diagnosis of minor depression, dysthymia or MDD as a combined group was increased by 8.03 [95% CI, 2.35-27.46; p < .01]. Smoking did not reliably predict depression at T2 or T3 and did not reliably predict persistent depression. Smoking increased the likelihood of being classified as depressed according to study criteria at least once during the study period by 5.19 [95% CI, 1.51-17.82; p < .01]. Smoking independently predicted worse mental HRQOL.

Conclusions

The findings support a role for smoking as an independent predictor of depression in CAD patients, particularly in the first 3 months post-cardiac event. The well-established imperative to encourage smoking cessation in these patients is augmented and the findings may add to the evidence for smoking cessation campaigns in the primary prevention of depression.

Quantitative Heel Ultrasound (QUS) measures of bone quality in association with mood and anxiety disorders

BACKGROUND

The common mental disorders are potential risk factors for low bone mass as a result of disease and/or medication-related processes. Quantitative heel ultrasound (QUS) is a portable and relatively cheap screening tool for determining fracture risk. Thus, we investigated the association between QUS parameters, mood and anxiety disorders in a population-based sample of 745 men and 897 women.

METHODS

Using a clinical interview (SCID-I/NP), mood and anxiety disorders were identified. Bone quality was established using QUS and included the following parameters: Broadband Ultrasound Attenuation (BUA), Speed of Sound (SOS) and Stiffness Index (SI). Anthropometry, socio-economic status (SES), medication use and lifestyle factors were determined.

RESULTS

In men, mood and anxiety disorders were associated with lower age-weight- and smoking-adjusted SOS, BUA and SI. In women, age was an effect modifier. Among younger women (≤ 40yr), mood disorders were associated with lower age-weight- and smoking-adjusted SOS and SI but not BUA. No differences were detected in older women or women with anxiety disorders. These patterns persisted after adjustment for activity, alcohol, calcium intake, SES and medications.

LIMITATIONS

Cross-sectional study design, and possible residual or unrecognised confounding.

CONCLUSION

Our data suggest that bone quality, as measured by QUS, is reduced among men and younger women with a history of mood disorders. Furthermore, an inverse association between anxiety disorders and bone quality was evident for men. Thus, QUS may be a useful screening tool for determining fracture risk within these populations.

The effects of apoptosis vulnerability markers on the myocardium in depression after myocardial infarction

BACKGROUND

There is an increased incidence of major depressive disorder (MDD) in individuals after myocardial infarction (MI), but the pathophysiological processes mediating this association are unclear. Our previous study demonstrated an increase in pro-apoptotic pathways in the myocardium and hippocampus in MDD, which was reversed by venlafaxine. This study aimed to attempt to confirm the effects of apoptosis vulnerability markers on the myocardium in a model of depression after myocardial infarction.

METHODS

Rats were divided into four groups: sham (N = 8), depression (N = 8, chronic mild unpredictable stress and separation were used in the depression group), MI (N = 13) and post-MI depression (N = 7). The rats in all four groups underwent the same open field and sucrose preference behavioral tests. Evan Blue staining was used to determine the area at risk of myocardial infarction in the left ventricle, and 2,3,5-triphenyl tetrazolium chloride (1.5% TTC) dye was used to detect the size of the myocardial infarction. The expression of bax and bcl-2 protein in the myocardium was investigated by immunohistochemistry, and the mRNA expression of bax, bcl-2 and caspase-3 in the myocardium was investigated by real time RT-PCR. Apoptosis was estimated in the myocardium by measuring the Bax:Bcl-2 ratio.

RESULTS

In the depression and post-MI depression rats, there were significantly decreased movements and total sucrose consumption, modeling behavioral deficits and an anhedonic-like state. In terms of myocardial infarction size, no difference was seen between the MI and post-MI depression groups. There was an up-regulated Bax:Bcl-2 ratio in the depression, MI and post-MI depression groups. Furthermore, in the latter group, there was a greater up-regulated Bax:Bcl-2 ratio. However, caspase-3 did not differ among the four groups.

CONCLUSIONS

These results of this animal model suggest that active pro-apoptotic pathways may be involved in the nexus between myocardial infarction and depression. This mechanism may be germane to understanding this relationship in humans.

The effect of semelil (angipars®) on bone resorption and bone formation markers in type 2 diabetic patients

Background and purpose of the study

Diabetes mellitus has been recognized as a major risk factor for osteoporosis in which bone turnover is affected by different mechanisms. As the morbidity, mortality and financial cost related to osteoporosis are expected to rise in Iran in coming years, and considering the efficacy of Angipars® for improvement of different ulcers which made it a new herbal drug in diabetic foot ulcer, there is a need to evaluate the effect of this new drug on different organs including bone resorption and bone formation markers.

Methods

In this randomized, double- blind clinical trial, 61 diabetic patients were included. The subjects were randomly divided into intervention and control groups. Subjects of intervention group received 100 mg of Angipars® twice a day. Laboratory tests including bone resorption and bone formation markers were performed at baseline and after 3 months.

Result

31 patients in study group and 30 patients in control group finished the study. The mean age of the study population and the mean disease duration was respectively 51.8 ± 6.2 and 7.5 ± 4.7 years with no significant differences between intervention and control patients. No statistically significant differences between patients and controls were observed in pyridinoline, osteocalcin, urine calcium, bone alkaline phosphatase and tumor necrosis factor (TNF-α). Only urine creatinine level significantly changed between two groups after 3 month of treatment (p-value: 0.029)

Conclusion

In conclusion, the findings of this study indicate that Semelil (Angipars®) had no beneficial or harmful effects on bone. It might be other effects of this new component on bone turnover process which need more studies and more time to be discovered.

The impact of statins on psychological wellbeing: a systematic review and meta-analysis

BACKGROUND

Cholesterol-lowering medications such as statins have anti-inflammatory and antioxidant properties, which may be beneficial for treating depression and improving mood. However, evidence regarding their effects remains inconsistent, with some studies reporting links to mood disturbances. We aimed to conduct a meta-analysis to determine the impact of statins on psychological wellbeing of individuals with or without hypercholesterolemia.

METHODS

Articles were identified using medical, health, psychiatric and social science databases, evaluated for quality, and data were synthesized and analyzed in RevMan-5 software using a random effects model.

RESULTS

The 7 randomized controlled trials included in the analysis represented 2,105 participants. A test for overall effect demonstrated no statistically significant differences in psychological wellbeing between participants receiving statins or a placebo (standardized mean difference (SMD) = -0.08, 95% CI -0.29 to 0.12; P = 0.42). Sensitivity analyses were conducted to separately analyze depression (n = 5) and mood (n = 2) outcomes; statins were associated with statistically significant improvements in mood scores (SMD = -0.43, 95% CI -0.61 to -0.24).

CONCLUSIONS

Our findings refute evidence of negative effects of statins on psychological outcomes, providing some support for mood-related benefits. Future studies could examine the effects of statins in depressed populations.

Co-prescription of medication for bipolar disorder and diabetes mellitus: a nationwide population-based study with focus on gender differences

BACKGROUND

Studies have shown a correlation between bipolar disorder and diabetes mellitus. It is unclear if this correlation is a part of common pathophysiological pathways, or if medication for bipolar disorder has negative effects on blood sugar regulation.

METHODS

The Norwegian prescription database was analyzed. Prescriptions for lithium, lamotrigine, carbamazepine and valproate were used as proxies for bipolar disorder. Prescriptions for insulin and oral anti-diabetic agents were used as proxies for diabetes mellitus. We explored the association between medication for bipolar disorder and diabetes medication by logistic regression

RESULTS

We found a strong association between concomitant use of medication to treat diabetes mellitus and mood stabilizers for the treatment of bipolar disorder. Females had a 30% higher risk compared to men of being treated for both disorders. Persons using oral anti-diabetic agents had higher odds of receiving valproate than either lithium or lamotrigine. Use of insulin as monotherapy seemed to have lower odds than oral anti-diabetic agents of co-prescription of mood stabilizers, compared to the general population.

CONCLUSIONS

This study showed a strong association between the use of mood stabilizers and anti-diabetic agents. The association was stronger among women than men.

Systemic illness moderates the impact of N-acetyl cysteine in bipolar disorder

OBJECTIVES

Bipolar disorder (BD) is intricately associated with chronic clinical conditions. Medical comorbidity is not only more prevalent in mood disorders, but is associated with increased costs, cognitive impairment and, ultimately, premature mortality. Oxidative stress and inflammation may mediate part of this association. To further investigate the association between medical comorbidity status and clinical improvement with adjuvant N acetyl cysteine (NAC) in the context of a placebo-controlled trial.

METHODS

Placebo-controlled randomized clinical trial assessing the effect of NAC over 24 weeks. Symptomatic and functional outcomes were collected over the study period. Medical comorbidities were self-reported, and we took special interest in cardiovascular and endocrine conditions. We evaluated change from baseline to endpoint and the interaction between change and reported medical comorbidities.

RESULTS

Fifty-one percent of patients reported have a cardiovascular or endocrine comorbidity. Although not found for depressive symptoms or quality of life, a significant interaction between medical comorbidity and change scores was consistently found for all functional outcomes. This indicated an advantage of NAC over placebo in those with a clinical comorbidity.

CONCLUSION

Systemic illness moderated only the effect of NAC on functioning, not on depression. Demonstrating an improvement in functional outcomes with an agent that modulates redox and inflammatory pathways, this study lends empirical support to the idea that medical and psychiatric comorbidity are additive in contributing to allostatic states. One intriguing possibility is that comorbid clinical illness could be a marker for more severe oxidative stress states--and thus guide antioxidant use--in BD.

The association between depressive and anxiety symptoms and bone mineral density in the general population: the HUNT Study

BACKGROUND

Psychiatric disorders may be risk factors for reduced bone mineral density (BMD). Longitudinal evidence is limited and this is yet to be examined among community-dwelling adults with anxiety. We aimed to investigate the cross-sectional and longitudinal relationships between anxiety and depressive symptoms and BMD.

METHOD

This study examined data from the second Nord-Trondelag Health Study (1995-1997; 1194 men and 7842 women) and a follow-up conducted in 2001 (697 men and 2751 women). Symptomatology was ascertained using the Hospital Anxiety and Depression Scale and BMD was measured at the forearm using single-energy X-ray absorptiometry. Information on medication use and lifestyle was self-reported, and these, together with anthropometric measures were tested in multivariate analyses.

RESULTS

In men, adjusted BMD was 2.6% lower at the ultradistal forearm for those with depressive symptoms and 2.6% lower at the ultradistal and 2.0% lower at the distal forearm for those with anxiety symptoms. In women, adjusted BMD at the distal and ultradistal forearm was lower for heavier women with depressive symptoms but this relationship diminished with decreasing weight. Forearm BMD was similar for women with or without anxiety symptoms. Longitudinally, neither depressive nor anxiety symptoms were associated with bone loss over 4.6 years.

LIMITATIONS

Findings cannot be generalised to other skeletal sites and a longer follow-up period may be necessary to detect differences in bone loss.

CONCLUSIONS

These results indicate that depressive and anxiety symptoms are cross-sectionally associated with reduced BMD. These findings provide further evidence to support monitoring BMD in individuals diagnosed with psychiatric illness.

Venlafaxine modulates depression-induced behaviour and the expression of Bax mRNA and Bcl-xl mRNA in both hippocampus and myocardium

OBJECTIVES

Major depressive disorder is associated with progressive brain changes and is frequently comorbid with cardiovascular disease. There may be shared pathophysiological pathways between cerebral and myocardial dysfunction that impact on apoptosis related proteins. Our aim was to examine behaviour changes of rats with chronic mild stress (CMS), explore the expression of Bax and Bcl-xl in the hippocampus and myocardium, and additionally evaluate the effects of venlafaxine on these molecular mechanisms.

METHODS

Rats were randomly divided into three groups. The behaviour was assessed using the open field and sucrose consumption tests. Gene expression was measured by RT-PCR.

RESULTS

In CMS, there was a significant reduction of movements and sucrose consumption, an increased Bax level and a decreased Bcl-xl level in both the hippocampus and myocardium. The venlafaxine group showed an increase in movements and sucrose consumption, as well as upregulated expression of Bcl-xl and downregulated expression of Bax in both the hippocampus and myocardium.

CONCLUSIONS

These results demonstrate that in CMS, there is an increase in pro-apoptotic pathways that is reversed by venlafaxine. This suggests that there are shared active biochemical pathways that may play a role in the process of neuroprogression that is seen in depression and cardiovascular disorders.

Pathways underlying neuroprogression in bipolar disorder: focus on inflammation, oxidative stress and neurotrophic factors

There is now strong evidence of progressive neuropathological processes in bipolar disorder (BD). On this basis, the current understanding of the neurobiology of BD has shifted from an initial focus on monoamines, subsequently including evidence of changes in intracellular second messenger systems and more recently to, incorporating changes in inflammatory cytokines, corticosteroids, neurotrophins, mitochondrial energy generation, oxidative stress and neurogenesis into a more comprehensive model capable of explaining some of the clinical features of BD. These features include progressive shortening of the inter-episode interval with each recurrence, occurring in consort with reduced probability of treatment response as the illness progresses. To this end, emerging data shows that these biomarkers may differ between early and late stages of BD in parallel with stage-related structural and neurocognitive alterations. This understanding facilitates identification of rational therapeutic targets, and the development of novel treatment classes. Additionally, these pathways provide a cogent explanation for the efficacy of seemingly diverse therapies used in BD, that appear to share common effects on oxidative, inflammatory and neurotrophic pathways.

Nutrition, mood and behaviour: a review

OBJECTIVE

To conduct a critical review of recent empirical research regarding mood, behaviour and nutrition factors including essential fatty acids, macronutrients, micronutrients and food additives.

METHOD

A literature search of databases Medline, PsycInfo, CINAHL and Embase up to October 2008. The search emphasised empirical research published in the last 10 years and also included older literature. Studies in both adults and children were addressed.

RESULTS

Research into omega-3 fatty acids has been substantial but evidence for their potential in treating mood and behaviour is modest. In comparison, there has been much less research into carbohydrate and protein intakes and little evidence for their ability to influence mood and behaviour. Recent trials with food additives suggest their removal from the diet may benefit susceptible children with hyperactivity disorders. Micronutrient supplementation appears to improve mood only in those who were initially deficient in micronutrients.

CONCLUSIONS

More stringent research designs such as longitudinal studies and the use of biologically inert placebos within randomised controlled trials are needed before supplemental use of omega-3 fatty acids to treat disorders of mood and behaviour can be recommended. Caution is advised regarding the indiscriminate use of diets free of artificial food additives in managing hyperactivity disorders, as they may place an undue burden on individuals and their families. Should omega-3 fatty acid supplementation or the elimination of certain food additives be established as effective, they may provide cost-effective, accessible and well-tolerated adjuncts to standard psychiatric treatments for mood and behavioural disturbances.

Depression as a risk factor for osteoporosis

Osteoporosis is a major public health threat. Multiple studies have reported an association between depression and low bone mineral density, but a causal link between these two conditions is disputed. Here we review the endocrine and immune alterations secondary to depression that might affect bone mass. We also discuss the possible role of poor lifestyle in the etiology of osteoporosis in subjects with depression and the potential effect of antidepressants on bone loss. We propose that depression induces bone loss and osteoporotic fractures, primarily via specific immune and endocrine mechanisms, while poor lifestyle habits and use of specific antidepressants are potential contributory factors.