Cholesterol and psychological well-being

Evidence for a causal link between lipoprotein (a) and mental disorders: A retrospective and Mendelian randomization study

STUDY OBJECTIVES

Lipoprotein (a) [Lp(a)] is a biomarker of atherosclerotic cardiovascular disease, but its role in mental disorders is controversial. Our study aimed to explore the causality between Lp(a) levels and mental disorders by combining retrospective and Mendelian randomization (MR) studies.

METHODS

All genome-wide association study datasets used in the MR study were obtained from UK Biobank, FinnGen, and the Psychiatric Genomics Consortium. The matched case-control study were based on electronic health records from the Second Affiliated Hospital of Nanchang University and NHANES III cohort.

RESULTS

In the MR analysis, Lp(a) had a positive causal effect on the longest period of depression [1.05 (1.02-1.08), P = 0.0001], the number of depressive episodes [1.03 (1.01-1.06), P = 0.009] and a weak negative effect on memory loss [0.84 (0.72-0.99), P = 0.039]. Meanwhile, bipolar and major depressive disorder status was causally associated with significantly lower Lp(a) levels [0.96 (0.93-0.98), P = 0.003]. Retrospective study revealed low Lp(a) levels were associated with a significantly higher risk of depression (n = 670) [1.273 (1.007, 1.609), P = 0.044], anxiety (n = 1284) [1.231 (1.041, 1.456), P = 0.015] and major depression (n = 538) [1.364 (1.012,1.841), P = 0.042].

CONCLUSIONS

This study found there is a causal relationship between the number and longest period of depressive episodes or memory loss and Lp(a), while bipolar disorder and major depressive disorder were associated with a significant causal effect on reduced Lp(a) levels. Future studies should focus on whether a sustained decrease in Lp(a) levels could cause the development of mental disorders, and which target value is suitable for clinical practice.

Impacts of gender and lifestyle on the association between depressive symptoms and cardiovascular disease risk in the UK Biobank

We investigated the effects of gender and lifestyle on the association between frequency of depressive symptoms and CVD risk. The UK Biobank is a national prospective cohort study that recruited 502,505 participants aged 40-69 years between 2006 and 2010. Participants without CVD were classified as having low, moderate, high, or very high frequency of depressive symptoms according to the number of days they felt depressed in a 2-week period. UKBB data include self-reported questionnaires covering lifestyle behaviors such as smoking, physical activity, eating habits, and sleep duration. The primary outcomes included incident CVD including coronary artery disease, ischemic stroke, hemorrhagic stroke, peripheral artery disease, atrial fibrillation/flutter, and heart failure. Cox proportional hazard models were used to evaluate the effects of gender and lifestyle on the association of frequency of depressive symptoms and CVD risk. During a median follow-up of 8.9 years, 27,394 (6.3%) developed CVD. The frequency of depressive symptoms increased the risk of CVD according to low, moderate, high, and very high frequency of depressive symptoms (P for trend < 0.001). The adjusted CVD risk was 1.38-fold higher for participants with very high frequency of depressive symptoms compared to those with low frequency of depressive symptoms (HR 1.38, 95% CI 1.24-1.53, P < 0.001). The correlation between frequency of depressive symptoms and CVD risk was more remarkable in females than in males. In participants with high or very high frequency of depressive symptoms, the individual lifestyle factors of no current smoking, non-obesity, non-abdominal obesity, regular physical activity, and appropriate sleep respectively was associated with lower CVD risk by 46% (HR 0.54, 95% CI 0.48-0.60, P < 0.001), 36% (HR 0.64, 95% CI 0.58-0.70, P < 0.001), 31% (HR 0.69, 95% CI 0.62-0.76, P < 0.001), 25% (HR 0.75, 95% CI 0.68-0.83, P < 0.001), and 22% (HR 0.78, 95% CI 0.71-0.86, P < 0.001). In this large prospective cohort study, a higher frequency of depressive symptoms at baseline was significantly associated with increased risk of CVD in the middle-aged population, and this relationship was prominent in women. In the middle-aged population with depressive symptoms, engaging in a healthier lifestyle could prevent CVD risk.

Sex Differences in Hemoglobin A1c Levels Related to the Comorbidity of Obesity and Depression

Background: Obesity (OB) and major depressive disorder (MDD) are chronic conditions associated with disease burden, and their comorbidity appears more common among women. Mechanisms linking these conditions may involve inflammatory and metabolic pathways. The goal of this study was to evaluate the impact of MDD on relationships between OB and cardiometabolic function, and sex differences therein. Materials and Methods: Adult offspring from the New England Family Studies (NEFS) were assessed at ages 39-50, including anthropometry, cardiometabolic profile assays, and metabolic syndrome. Individuals were grouped by body mass index (BMI) and MDD status: healthy weight with (n = 50) or without MDD (n = 95) and obese with (n = 79) or without MDD (n = 131). The interaction of (recurrent) MDD and BMI on cardiometabolic markers was tested using quantile regression models. Results: Participants with MDD exhibited significantly higher hemoglobin A1c (HbA1c) than those without MDD (5.60% vs. 5.35%, p < 0.05). Women with comorbid recurrent MDD and OB had higher HbA1c levels compared to obese women without MDD (5.75% vs. 5.44%, p < 0.05); an interaction between MDD and BMI status was not observed among men. Conclusions: We demonstrated sex differences in the interaction between BMI and recurrent MDD status on a primary biomarker for diabetes risk, suggesting a common metabolic pathway predisposing women to these comorbid conditions. Further investigation is needed to identify mechanisms that may lead to more effective, sex-dependent screening and therapies.

Evaluation of the causal effects between subjective wellbeing and cardiometabolic health: mendelian randomisation study

OBJECTIVES

To investigate whether the association between subjective wellbeing (subjective happiness and life satisfaction) and cardiometabolic health is causal.

DESIGN

Two sample, bidirectional mendelian randomisation study.

SETTING

Genetic data taken from various cohorts comprised of the general population (mostly individuals of European ancestry, plus a small proportion of other ancestries); follow-up analysis included individuals from the United Kingdom.

PARTICIPANTS

Summary data were used from previous genome wide association studies (number of participants ranging from 83 198 to 339 224), which investigated traits related to cardiovascular or metabolic health, had the largest sample sizes, and consisted of the most similar populations while minimising sample overlap. A follow-up analysis included 337 112 individuals from the UK Biobank (54% female (n=181 363), mean age 56.87 years (standard deviation 8.00) at recruitment).

MAIN OUTCOME MEASURES

Subjective wellbeing and 11 measures of cardiometabolic health (coronary artery disease; myocardial infarction; total, high density lipoprotein, and low density lipoprotein cholesterol; diastolic and systolic blood pressure; body fat; waist to hip ratio; waist circumference; and body mass index).

RESULTS

Evidence of a causal effect of body mass index on subjective wellbeing was seen; each 1 kg/m2 increase in body mass index caused a -0.045 (95% confidence interval -0.084 to -0.006, P=0.02) standard deviation reduction in subjective wellbeing. Follow-up analysis of this association in an independent sample from the UK Biobank provided strong evidence of an effect of body mass index on satisfaction with health (β=-0.035 unit decrease in health satisfaction (95% confidence interval -0.043 to -0.027) per standard deviation increase in body mass index, P<0.001). No clear evidence of a causal effect was seen between subjective wellbeing and the other cardiometabolic health measures, in either direction.

CONCLUSIONS

These results suggest that a higher body mass index is associated with a lower subjective wellbeing. A follow-up analysis confirmed this finding, suggesting that the effect in middle aged people could be driven by satisfaction with health. Body mass index is a modifiable determinant, and therefore, this study provides further motivation to tackle the obesity epidemic because of the knock-on effects of higher body mass index on subjective wellbeing.

African Americans, Depression, and Suicide Risk

The aim of the current study was to determine which variable would be a better predictor of suicide risk: perceived social support or serum cholesterol level. There was a significant negative correlation between suicide risk and perceived social support but no significant correlation between suicide risk and serum cholesterol. Perceived social support was a better predictor of suicide risk than was serum cholesterol level and accounted for 17% of the variance. Depressed patients with a history of suicide attempt had a significantly lower serum cholesterol level, scored significantly higher on the Suicide Risk Scale, and scored significantly lower on the Perceived Social Support Scale than did depressed patients with no history of suicide attempt. Findings suggest that perceived social support is a better predictor of suicide risk for depressed African Americans.

Age-dependent effect of high cholesterol diets on anxiety-like behavior in elevated plus maze test in rats

Background

Cholesterol is an essential component of brain and nerve cells and is essential for maintaining the function of the nervous system. Epidemiological studies showed that patients suffering from anxiety disorders have higher serum cholesterol levels. In this study, we investigated the influence of high cholesterol diet on anxiety-like behavior in elevated plus maze in animal model and explored the relationship between cholesterol and anxiety-like behavior from the aspect of central neurochemical changes.

Methods

Young (3 weeks old) and adult (20 weeks old) rats were given a high cholesterol diet for 8 weeks. The anxiety-like behavior in elevated plus maze test and changes of central neurochemical implicated in anxiety were measured.

Results

In young rats, high cholesterol diet induced anxiolytic-like behavior, decreased serum corticosterone (CORT), increased hippocampal brain-derived neurotrophic factor (BDNF), increased hippocampal mineralocorticoid receptor (MR) and decreased glucocorticoid receptor (GR). In adult rats, high cholesterol diet induced anxiety-like behavior and increase of serum CORT and decrease of hippocampal BDNF comparing with their respective control group that fed the regular diet.

Discussion

High cholesterol diet induced age-dependent effects on anxiety-like behavior and central neurochemical changes. High cholesterol diet might affect the central nervous system (CNS) function differently, and resulting in different behavior performance of anxiety in different age period.

Anxiogenic Effects of Acute Injection of Sesame oil May be Mediated by β-1 Adrenoceptors in the Basolateral Amygdala

PURPOSE

A few studies have indicates that the sesame oil influences anxiety, but many reports show that β-1 adrenoceptors (ARs) of the basolateral amygdala (BLA) plays a pivotal role in this regard. Therefore, in this study the effect of acute injection of sesame oil on anxiety-like behavior in the presence and absence of the BLA β-1 ARs in the male Wistar rats were investigated.

METHODS

Guide cannulas, for seven groups of rats, were implanted bilaterally into the BLA. Two weeks after the stereotaxic surgery, anxiety-like behaviors (the OAT%, OAE % and locomotor activity) were evaluated by Elevated Plus-Maze (EPM) for all groups. 3 groups received different volumes of sesame oil (i.p.) and they were compared with control group (received saline via i.p.), and the anxiogenic volume of sesame oil (1.5ml/kg) was determined. Then, 3 other groups received constant effective volume of sesame oil (1.5ml/kg) along with 3 different doses of betaxolol, selective β-1 ARs antagonist, intra BLA microinjection in order to be compared with sesame oil group (1.5 ml/kg).

RESULTS

The acute injection of sesame oil with the volume dependent manner showed an anxiogenic effect with reduction of the OAT% and OAE% which the maximum effect of sesame oil was observed in the dose of 1.5mg/kg. Also, betaxolol with dose dependent manner attenuated the anxiogenic effects of sesame oil (1.5mg/kg), but this reduction could not remove the anxiety effects completely.

CONCLUSION

It seems that the sesame oil acute (i.p.) injection induces anxiety, and this effect is attenuated by inhibition of β-1ARs in the BLA.

Relationship of Psychosocial Risk Factors, Certain Personality Traits and Myocardial Infarction in Indians: A Case-control Study

Objective:

To investigate the relationship of psychosocial factors (lack of social support, stress and subjective well-being) and personality traits with myocardial infarction (MI).

Materials and Methods:

A case–control study involving 100 cases and 100 matched controls was conducted in Lok Nayak Hospital, New Delhi.

Results:

Stress over 1 year was significantly higher in cases (P < 0.001). However, difference was not significant when scores of social support (P = 0.2), Presumptive Stressful Life Event (PSLE) over lifetime (P = 0.058) and subjective well-being (P = 0.987) were compared. MI was significantly associated with hyperactive (P < 0.001), dominant (P = 0.03), egoistic (P < 0.001) and introvert (P < 0.001) personalities.

Conclusion:

Certain personality traits and recent stress may be important risk factors of MI, especially in Indians. The finding may have implications on the preventive strategies planned for MI patients.

Use of antidepressants and risk of colorectal cancer: a nested case-control study

BACKGROUND

Animal studies suggest that selective serotonin reuptake inhibitors (SSRI) retard the growth of colorectal tumours, whereas tricyclic antidepressants increase the risk of colorectal cancer. We aimed to assess whether SSRI use was associated with a decreased risk of colorectal cancer, and tricyclic-antidepressant use with an increased risk of colorectal cancer.

METHODS

We did a population-based nested case-control study from Jan 1, 1981, to Dec 31, 2000, of people aged 5-85 years who were registered with Saskatchewan Health and eligible for prescription-drug benefit. Between Jan 1, 1981, and Dec 31, 2000, 6544 cases with colorectal cancer were identified from the Saskatchewan Cancer Agency registry and analysed for use of tricyclic antidepressants; between Jan 1, 1991, and Dec 31, 2000, 3367 cases with colorectal cancer were identified from the Saskatchewan Cancer Agency registry and analysed for SSRI use. For every case, four eligible controls matched for age, sex, and calendar time (ie, free of any cancer in calendar month of case diagnosis) were selected randomly by a statistician who used incidence density sampling. By use of conditional logistic regression, we assessed incidence-rate ratios of having colorectal cancer in association with use of antidepressants, analysing dose and time of use.

FINDINGS

A decreased risk of colorectal cancer was associated with high (ie, >6.0x10(-6) mol per day) daily SSRI dose during 0-5 years before diagnosis (incidence-rate ratio 0.70 [95% CI 0.50-0.96], p for trend=0.0172), adjusted for age, sex, use of non-steroidal anti-inflammatory drugs in the same period, and SSRI use during 6-10 years before index date (ie, date of diagnosis for a case and the same date for matched controls). No consistent relation was recorded for risk of colorectal cancer and use of tricyclic antidepressants.

INTERPRETATION

SSRI use might inhibit the growth of colorectal tumours through an antipromoter effect or direct cytotoxic effect. Further investigation is needed, with more complete assessment of confounders such as lifestyle factors (eg, diet), use of drugs, and comorbidity (eg, diabetes or inflammatory bowel disease) that might affect the occurrence of colorectal cancer.

Psychological distress, physical illness, and risk of coronary heart disease

STUDY OBJECTIVE

The aims of this study are to confirm the association between psychological distress and coronary heart disease (CHD) using an epidemiological community study with hospital admissions data and to examine if any association is explained by existing illness.

DESIGN

Prospective cohort study modelling the association between psychological distress, measured using the 30 item general health questionnaire (GHQ), and hospital admissions data for CHD (ICD 410-414), using proportional hazards modelling adjusted for sociodemographic, CHD risk factors, and angina, bronchitis, diabetes, ischaemia, and stroke.

SETTING

Two suburbs of Glasgow, Renfrew and Paisley, in Scotland.

PARTICIPANTS

6575 men and women aged 45-64 years from Paisley.

MAIN RESULTS

Five year CHD risk in distressed men compared with non-distressed men was 1.78 (95% confidence intervals (CI), 1.15 to 2.75) in age adjusted analysis, 1.78 (95% CI, 1.14 to 2.79) with sociodemographic and CHD risk factor adjustment, and 1.61 (95% CI 1.02 to 2.55) with additional adjustment for existing illness. Psychological distress was unrelated to five year CHD risk in women. In further analysis, compared with healthy, non-distressed men, distressed physically ill men had a greater risk of CHD than non-distressed physically ill men, a relative risk of 4.01 (95% CI 2.42 to 6.66) compared with 2.12 (95% CI 1.35 to 3.32).

CONCLUSION

The association of psychological distress with an increased risk of five year CHD risk in men could be a function of baseline physical illness but an effect independent of physical illness cannot be ruled out. Its presence among physically ill men greatly increases CHD risk.

Lipid metabolism and insulin resistance in depressed patients: significance of weight, hypercortisolism, and antidepressant treatment

Major depression increases cardiovascular risk despite lower cholesterol levels. Little is known about effects of antidepressants on metabolic risk factors. We studied lipoprotein composition, insulin sensitivity (quantitative insulin sensitivity check index), and saliva cortisol in 78 depressed patients before and after 35 days of amitriptyline or paroxetin treatment. Data were analyzed by principal component factor analyses and analysis of variance (ANOVA). At baseline, quantitative insulin sensitivity check index was inversely correlated with cortisol (r = -0.46; P = 0.005) in normal weight patients, with body mass index in overweight patients (r = -0.50; P < 0.001). In overweight patients, hypercortisolemia correlated inversely with total and low density lipoprotein cholesterol (eg, cortisol at 4:00 PM and low density lipoprotein cholesterol: r = -0.49, P = 0.002). After treatment, quantitative insulin sensitivity check index was unchanged. Triglycerides increased in responders to amitriptyline only (P < 0.05). Parameters of cholesterol metabolism improved slightly without differences between treatment groups (eg, high density lipoprotein: pre 43.5 +/- 12.0; post 47.6 +/- 13.0 mg/dL; P = 0.01; low density lipoprotein triglycerides, a measure of low density lipoprotein atherogenicity: pre 458 +/- 120; post 415 +/- 130 mg/g; P < 0,01). The inverse correlation of cortisol and cholesterol, at least in the obese subgroup, proposes a mechanism for the known association of depression with low cholesterol. As determinants of plasma lipids in major depression, we identified body mass index, insulin sensitivity, and cortisol. Although uncontrolled, our data suggest that treatment of depression exerts a mainly beneficial effect on lipid regulation.

Quality of life after coronary artery bypass graft: results from the POST CABG Trial

OBJECTIVES

The POST CABG (Post Coronary Artery Bypass Graft) Trial showed that aggressive lowering of low-density lipoprotein (LDL) cholesterol levels reduced the progression of atherosclerosis in saphenous vein grafts. In the extended follow-up phase, aggressive lowering of LDL cholesterol levels was associated with reduced rates of clinical events. Low-dose anticoagulation therapy did not reduce the progression of atherosclerosis. We conducted this analysis to determine the effects of both lipid-lowering and low-dose anticoagulation therapy on health-related quality of life (HRQL).

DESIGN

Randomized clinical trial, factorial design.

SETTING

Outpatients in five tertiary care medical centers.

PATIENTS

A cohort of 852 patients enrolled in the POST CABG Trial completed an HRQL questionnaire at baseline, and at the year 2 and year 4 follow-up visits.

INTERVENTION

Aggressive LDL cholesterol lowering vs moderate LDL cholesterol lowering, and low-dose warfarin vs placebo.

MEASUREMENTS

Domains included emotional status, basic physical and social functioning, perceived health status, symptoms of pain, a variety of physical symptoms, and global life satisfaction.

RESULTS

Overall, there were no indications of systematic differences among treatment groups for any of the HRQL parameters at baseline, year 2, or year 4.

CONCLUSIONS

These data indicate that patients did not experience detrimental or beneficial effects on HRQL parameters while receiving LDL cholesterol-lowering therapy that had demonstrable benefits for treatment of atherosclerosis.

Serum cholesterol concentrations are associated with visuomotor speed in men: findings from the third National Health and Nutrition Examination Survey, 1988-1994

BACKGROUND

Current international recommendations advise aggressive treatment of relative hypercholesterolemia despite an incomplete understanding of any neurobehavioral effects of low or lowered serum cholesterol.

OBJECTIVE

The objective was to examine the relation between serum cholesterol concentrations and performance in immediate memory, visuomotor speed, and coding speed tests.

DESIGN

The participants were 4110 adults aged 20-59 y who completed a set of neurobehavioral tests and had blood specimens collected as a part of the third National Health and Nutrition Examination Survey, 1988-1994.

RESULTS

After adjustment for sociodemographic variables, serum trace elements and vitamins, dietary energy intake, and risk factors for cardiovascular disease, we found inverse linear associations of serum total cholesterol and non-HDL cholesterol with visuomotor speed in men. The least-squares mean (+/- SE) visuomotor speeds were 231.6 +/- 2.6, 224.0 +/- 2.2, and 218.9 +/- 2.5 ms, respectively, for men with serum total cholesterol concentrations below the 25th, between the 25th and the 75th, and at or above the 75th percentile (P for trend < 0.001) and were 231.7 +/- 2.7, 225.8 +/- 2.4, and 214.1 +/- 2.3 ms, respectively, for men with a non-HDL-cholesterol concentration below the 25th, between the 25th and the 75th, and at or above the 75th percentile (P for trend < 0.001). No significant associations were observed between memory or coding speed and the selected serum cholesterol measures in men, and the scores of the 3 neurobehavioral tests were unrelated to serum cholesterol in women.

CONCLUSION

Low serum total cholesterol and non-HDL cholesterol are associated with slow visuomotor speed in young and middle-aged men.

No evidence for an association between serum cholesterol and the course of depression and suicidality

In a number of previous reports, an association of altered, in most cases lower, serum cholesterol levels with depression, suicidal ideation and current or past suicidal behavior has been suggested. In this investigation, the course of serum cholesterol concentrations was measured in depressed patients during treatment. Ninety-two inpatients with a major depressive episode were included. Serum lipid concentrations were assessed at admission, after 1 week and after 4 weeks of antidepressant treatment. Degrees of depression and suicidality were measured with the Hamilton Depression Rating Scale. Although there was a significant reduction in depression and suicidality scores, neither a significant change in serum cholesterol levels nor a correlation between cholesterol levels and clinical improvement was found. Further, there were no significant differences in lipid levels between patients with and without a history of attempted suicide. In patients who had used a violent method, there was a trend for lower total cholesterol levels compared to those who had poisoned themselves. The results of this study do not support the hypothesis of an association of serum cholesterol with the course of depression and suicidal ideation. Cholesterol levels do not appear to be an appropriate biological marker for suicidality during the first 4 weeks of treatment in patients with a major depressive episode.

Neuropsychiatric effects of cardiovascular drug therapy

Various cardiovascular drugs have been shown to have neuropsychiatric effects that can be harmful or therapeutically beneficial to patients. As an example, both sedation and mental depression have been described in patients receiving centrally acting antihypertensive drugs and beta-adrenergic blockers, related to their antiadrenergic actions. In contrast, because of these antiadrenergic actions, agents like clonidine have been used to treat opiate, alcohol, and nicotine withdrawal, while beta blockers have been used to treat symptoms of performance anxiety, migraine, and psychocardiac disorders. Some antiarrhythmic drugs have been associated with delirium, and digitalis toxicity has been shown to cause hallucinations, mania, euphoria, and depression. The calcium-channel blocker verapamil has been used as an adjunctive treatment in patients with bipolar disorders. Since neuropsychiatric symptoms are seen in patients with cardiovascular disease, clinicians should be aware of the possible relationship between these symptoms and concurrent cardiovascular drug therapy.

Serum cholesterol levels and mood symptoms in the postpartum period

During pregnancy, the total serum cholesterol concentration rises up to 43%, followed by a rapid fall after delivery. Mild depressive symptoms ('postpartum blues') are a common complication of the puerperium and affect 30-85% of women in the early postpartum period. Based on these observations, it has been suggested that the sudden fall in cholesterol levels after delivery could serve as a 'natural model' to test the suggested association between cholesterol and mood. The present study was designed to expand the database concerning the association between cholesterol levels and mood in the postpartum period and to address some methodological problems raised by previous studies. Forty-seven healthy primiparous women were interviewed with a structured clinical interview on two occasions: during late pregnancy (median: day -20 before the expected delivery) and during the early postpartum period (median: day 32 after delivery). On both occasions, serum concentrations of total and HDL cholesterol were measured and mood symptoms were assessed with the state form of Spielberger's State-Trait Anxiety Index (STAI), the state form of the State-Trait Anger Scale (STAS), and the Beck Depression Inventory (BDI). We found significant, albeit moderate, relationships between serum cholesterol levels and mood symptoms in the postpartum period that were not present during late pregnancy. Lower postpartum levels of total cholesterol were associated with symptoms of anxiety (r=-0.30, P=0.04), anger/hostility (r=-0.31, P=0.04), and depression (r=-0.35, P=0.02), and lower postpartum levels of HDL cholesterol were associated with symptoms of anxiety (r=-0.34, P=0.02). This study confirms that the physiological fall in blood lipids in the postpartum period can be a useful model to test the relationship between serum cholesterol levels and mood.

Improving mental health through nutrition: the future

Tell me what you eat, and I will tell you what you are (Anthelme Brillat-Savarin). When I behold a fashionable table set out in all its magnificence, I fancy that I see gouts and dropsies, fever and lethargies, with other innumerable distempers, lying in ambuscade among the dishes. Nature delights in the most plain and simple diet. Every animal, but man, keeps to one dish. Herbs are the food of this species, fish of that, and flesh of a third. Man falls upon everything that comes in his way; not the smallest fruit or excrescence of the earth, scarce a berry or a mushroom can escape him (Joseph Addison). The pleasures of the palate deal with us like the Egyptians thieves, who strangle those whom they embrace (Seneca). Let food be your medicine and medicine be your food (Hippocrates).

A healthy body, a healthy mind: long-term impact of diet on mood and cognitive function

Certain dietary risk factors for physical ill health are also risk factors for depression and cognitive impairment. Although cholesterol lowering has been suggested to increase vulnerability to depression, there is better support for an alternative hypothesis that intake of n-3 long-chain polyunsaturated fatty acids can affect mood (and aggression). Possible mechanisms for such effects include modification of neuronal cell membrane fluidity and consequent impact on neurotransmitter function. Stronger evidence exists concerning a role for diet in influencing cognitive impairment and cognitive decline in older age, in particular through its impact on vascular disease. For example, cognitive impairment is associated with atherosclerosis, type 2 diabetes and hypertension, and findings from a broad range of studies show significant relationships between cognitive function and intakes of various nutrients, including long-chain polyunsaturated fatty acids, antioxidant vitamins, and folate and vitamin B12. Further support is provided by data on nutrient status and cognitive function. Almost all this evidence, however, comes from epidemiological and correlational studies. Given the problem of separating cause and effect from such evidence, and the fact that cognitive impairment and cognitive decline (and depression) are very likely to be significant factors contributing to the consumption of a poor diet, greater emphasis should now be placed on conducting intervention studies. An efficient approach to this problem could be to include assessments of mood and cognitive function as outcome measures in studies designed primarily to investigate the impact of dietary interventions on markers of physical health.

Age specificity of the relationship between serum cholesterol and mood in obese women

Despite increasing evidence of an association between lower cholesterol levels and negative mood, no study has specifically investigated this relationship in obese people, a population at high risk for both dyslipidaemia and depression. Data on serum cholesterol and mood were collected in a group of 73 healthy women, aged 16 to 76 years, with different degrees of obesity and widely varying total cholesterol concentrations. Mood was assessed using three self-rated scales: the Toronto Alexithymia Scale (TAS-20), the State-Trait Anger Scale (STAS), and the Beck Depression Inventory (BDI). The association between lower total cholesterol levels and negative mood was age-dependent. No significant association was found in the younger age group (<50 years). In contrast, in the subgroup of older women, serum cholesterol was negatively and significantly correlated with the TAS-20 and the STAS. The negative correlation between serum cholesterol and the BDI was nearly statistically significant. Restricting analysis to the subjects in the highest quartile of the age distribution (>60 years) yielded stronger correlations between cholesterol and mood. In this sample of obese women, the relationship between lower cholesterol levels and negative mood was age-specific and limited to the older age group. The results of this study suggest that preventive programs or drug treatments for reducing cholesterol levels in elderly obese women should include a careful evaluation of mood state.

Total serum cholesterol in relation to psychological correlates in parasuicide

BACKGROUND

Low cholesterol may act as a peripheral marker for parasuicide.

AIMS

To examine the relationship between total serum cholesterol and psychological parameters in parasuicide.

METHOD

Total serum cholesterol and self-rated scores for impulsivity, depression and suicidal intent were measured in 100 consecutive patients following parasuicide, pair-matched with normal and psychiatric control groups.

RESULTS

Backward, stepwise multiple regression analysis revealed a significantly lower mean cholesterol in the parasuicide population (P < 0.01). Across all groups there was an independent significant (P < 0.01) negative correlation between cholesterol and self-reported scores of impulsivity. No correlation existed between cholesterol and scores for depression or suicidal intent.

CONCLUSIONS

The data confirm previous reports of low cholesterol in parasuicide. This is the first reported investigation of the construct of impulsivity in relation to cholesterol. We hypothesise that the reported increased mortality in populations with low cholesterol may derive from increased suicide and accident rates consequent on increased tendencies to impulsivity in these populations.

Randomized trial of the effects of cholesterol-lowering dietary treatment on psychological function

PURPOSE

Epidemiological studies have suggested that cholesterol lowering could affect psychological functioning. This study was designed to test whether cholesterol-lowering diets adversely affect mood and cognitive function.5.2 mM [198 mg/dL]) to either a low-fat diet, a Mediterranean diet, or a waiting-list control. Cholesterol levels, psychological well-being (depression, anxiety, hostility), and cognitive function were assessed at baseline, 6 weeks, and 12 weeks.

RESULTS

Total serum cholesterol levels fell significantly more in the intervention groups (8.2% reduction) than in the control group (P <0.001). All three groups showed a modest improvement in psychological well-being during the 12-week treatment period, but there were no differences among the groups. There were no between-group differences on three measures of cognitive function, but for a fourth measure, which involved the task with the greatest processing load, the two intervention groups did significantly worse (P <0.001) than the control group. The change in performance was correlated with the change in total serum cholesterol level (r = 0. 21, P = 0.01).

CONCLUSIONS

Two dietary interventions that successfully lowered serum cholesterol levels had no adverse effect on mood. There was some evidence for a relative impairment in cognitive function in the treated groups in one of four cognitive tests, but additional studies will be required to determine the relevance of this finding.

Dieting, essential fatty acid intake, and depression

Studies have both supported and contested the proposition that lowering plasma cholesterol by diet and medications contributes to depression. Evidence suggests that an imbalance in the ratio of the essential fatty acids (EFAs), namely the n-6 and n-3 fatty acids, and/or a deficiency in n-3 fatty acids, may be responsible for the heightened depressive symptoms associated with low plasma cholesterol. These relationships may explain the inconsistent findings in trials of cholesterol-lowering interventions and depression. Dieting behaviors have similarly been associated with alterations in mood state. This review discusses studies of EFAs and depression and explores the involvement of dieting-related psychological factors as potential confounders.

Depression in late life: psychiatric-medical comorbidity

The links between late-life depression and the medical comorbidities that are often associated with it can be divided into two paths. The path from medical illness to depression reflects general mechanisms related to stress, disability, and loss, as well as more specific physiological mechanisms, including those related to subclinical cerebrovascular disease, adverse drug effects, and endocrine/metabolic effects. Similarly the path from depression to medical illness includes general mechanisms related to self-neglect, decreased adherence to medical treatments, maladaptive health-related behaviors, and, possibly, more specific physiological mechanisms including those related to altered endocrine and autonomic functions, in the clinical context, these two paths can interact to constitute a vicious cycle. With further research, it should be possible to translate current understanding in these areas into advances in both basic knowledge and treatments that could initiate virtuous cycles with beneficial effects for both menial and physical health.

Relations of trait depression and anxiety to low lipid and lipoprotein concentrations in healthy young adult women

OBJECTIVE

Recent evidence suggests that naturally occurring low cholesterol concentrations (<4.14 mmol/liter) are associated with depression as well as poor psychological health. For the most part, these associations have been observed in men. The current study assessed the relation of naturally occurring low lipid and lipoprotein concentrations to trait measures of depression and anxiety in 121 healthy young adult women.

METHODS

Fasting lipid samples were collected at the same time as health history. Trait depression and anxiety were assessed using the Neuroticism, Extraversion, Openness-Personality Inventory (NEO-PI) depression subscale and Spielberger's Trait Personality Inventory (STPI) anxiety subscale. Analyses were conducted using both univariate and multivariate procedures.

RESULTS

NEO depression was inversely associated with total cholesterol (p = .027), triglycerides (p = .012), and the ratio of total cholesterol to high-density lipoprotein cholesterol (p = .059). Similarly, STPI anxiety was inversely associated with total cholesterol (p = .002), low-density lipoprotein cholesterol (p = .016), triglycerides (p = .024), and ratio of total cholesterol to high-density lipoprotein cholesterol (p = .075). These associations were significant after adjustment for age, body mass index, physical activity, oral contraceptive use, and hostility. Neither depression nor anxiety was associated with high-density lipoprotein cholesterol. Univariate analyses indicated that women with low total cholesterol concentrations (<4.14 mmol/liter), relative to those with moderate to high cholesterol levels, were more likely to have higher scores on the NEO depression subscale (27 of 69 (39%) vs. 10 of 52 (19%)) and STPI anxiety subscale (24 of 69 (35%) vs. 11 of 52 (21%)).

CONCLUSIONS

In healthy young adult women, low lipid and lipoprotein concentrations are inversely associated with trait measures of depression and anxiety. These findings are independent of age, body mass index, physical activity, and other factors known to influence lipid concentrations.

The influence of climate on suicidal behaviour in Italy

A growing number of studies report an asymmetry in the seasonal distribution of suicides, with a peak in the late spring months for both sexes. The aim of this study is to verify if the climate, apart from its seasonal change, exerts a direct influence on suicidal behaviour. To this end, deaths by suicide in 17 Italian towns which all have a meteorologic station have been analyzed, taking into account some climatic indicators. Results of analyses show an unequal distribution of suicides with respect to latitude, with a peak in the North. The distribution of deaths by suicide shows a negative relationship with mean yearly temperature values, max and min, and with sun exposure indicators, and a positive, but less significant relationship with rainfall values. As far as climatic variables considered as a whole are concerned, stepwise regression identifies three relevant factors with significant relationships to suicide rates: humidity grade, rainfall mean, and sunlight exposure. These three climatic indicators explain up to 63% (Adj R2) of the variance in the distribution of suicide rates for both genders, with sunlight exposure offering the most significant contribution, when regressed on suicide rates via a multiple regression model. Higher suicide rates, therefore, correspond to dry places which are less exposed to the sun. However, the variable which shows the most significant correlation with suicide rates for both sexes is not a climatic one, but the percentage of the population aged 65 and over. The distribution of people at greater biological risk for possible disruption of brain neurochemistry (i.e. older people), therefore, predicts the distribution of suicide rates. Climate contributes to this biological risk by modifying both the responsiveness of the circuits that control mood and behaviour, and also the frequency and intensity of social interaction.

A theory of postoperative fatigue: an interaction of biological, psychological, and social processes

The concept of postoperative fatigue has been developed to explain the feelings of malaise and the reduction in activity during the convalescent period that follows surgery in humans. Fatigue has been assumed to reflect the degree of surgical trauma and to be a consequence of muscle weakness caused by physiological sequelae of the trauma. The evidence is inconsistent with this reductionist view. Instead we propose a theory that postoperative fatigue is based on an emotional and motivational change that has the function of ensuring inactivity so as to preserve homeostasis in vital systems in response to injury while preserving the physical capacity to respond to new challenge. This response, triggered by the patient's perception of the surgical stimulus, is prolonged by the influence of staff and patient expectations, which, in turn, reflect cultural beliefs in the necessity of convalescence. This theory can be tested by manipulation of clinical practice at pharmacological and psychological levels.

Depression, psychotropic medication, and risk of myocardial infarction. Prospective data from the Baltimore ECA follow-up

BACKGROUND

There is suggestive evidence that depression increases risk of myocardial infarction (MI), but there are no prospective studies in which the measure of depression corresponds to clinical criteria. This study examines prospectively whether a major depressive episode increases the risk of incident MI and evaluates the role of psychotropic medication use in this relationship.

METHODS AND RESULTS

The study is based on a follow-up of the Baltimore cohort of the Epidemiologic Catchment Area Study, a survey of psychiatric disorders in the general population. A history of major depressive episode, dysphoria (2 weeks of sadness), and psychotropic medication use were assessed in 1981, and self-reported MI was assessed in 1994. Sixty-four MIs were reported among 1551 respondents free of heart trouble in 1981. Compared with respondents with no history of dysphoria, the odds ratio for MI associated with a history of dysphoria was 2.07 (95% CI, 1.16 to 3.71), and the odds ratio associated with a history of major depressive episode was 4.54 (95% CI, 1.65 to 12.44), independent of coronary risk factors. In multivariate models, use of barbiturates, meprobamates, phenothiazines, and lithium was associated with an increased risk of MI, whereas use of tricyclic antidepressants and benzodiazepines was not. Among individuals with no history of dysphoria, only lithium use was significantly associated with MI.

CONCLUSIONS

These data suggest that a history of dysphoria and a major depressive episode increase the risk of MI. The association between psychotropic medication use and MI is probably a reflection of the primary relationship between depression and MI.

Serum cholesterol levels in patients with generalized anxiety disorder (GAD) and with GAD and comorbid major depression

OBJECTIVE

To investigate risk for cardiovascular disease in patients with GAD, as well as the effects of comorbid major depression (MD).

METHOD

Predrug-trial serum cholesterol and triglyceride levels were assessed in 38 patients with pure GAD and compared with those of 21 patients with mixed GAD and comorbid (MD).

RESULTS

Significantly higher cholesterol and triglyceride levels were found in the GAD group.

CONCLUSION

Increased noradrenergic activity may be responsible for elevations in lipid levels in patients with pure GAD.