Hyper- and hypocortisolism in bipolar disorder - A beneficial influence of lithium on the HPA-axis?

BACKGROUND: A hyperactive hypothalamic-pituitary-adrenal axis (HPA-axis) is a well-known phenomenon in bipolar disorder (BD). However, hypocortisolism has also been described and found associated with depression, low quality of life and cardiovascular risk factors in BD patients. Although the pathophysiology related to hypocortisolism in BD is largely unknown, hypocortisolism is associated with chronic stress exposure and after inducing an initial rise in cortisol long-term stress may result in a transition to hypocortisolism. BD patients are throughout life often exposed to chronic stress. We therefore hypothesized that higher age would be associated with lower HPA-axis activity especially among patients without previous mood stabilizing treatment. METHODS: This cross-sectional study consisted of 159 bipolar outpatients and 258 controls. A low-dose-dexamethasone-suppression-test (DST) was used to measure HPA-axis activity. RESULTS: Patients with BD showed a negative association between post DST cortisol and age (-3.0 nmol/l per year; p=0.007). This association gradually increased in subgroups that were naïve to lithium (-7.7 nmol/l per year; p=0.001) and "all mood stabilizers" (-11.4 nmol/l per year; p=0.004). Patients exhibiting hypercortisolism were characterized by younger age and female gender, whereas patients exhibiting hypocortisolism were characterized by long disease duration without prophylactic lithium treatment as well as absence of current lithium medication. LIMITATIONS: Cross sectional study design. CONCLUSIONS: There was a negative association between HPA-axis activity and age in BD, rendering BD patients at risk for developing hypocortisolism. This association was most pronounced among patients without previous or current lithium prophylaxis.

Association between gastrointestinal symptoms and affectivity in patients with bipolar disorder.

AIM: To study if anxiety, depression and experience of stress are associated with gastrointestinal (GI) symptoms in patients with bipolar disorder. METHODS: A total of 136 patients with bipolar disorder (mean age 49.9 years; 61% women) and 136 controls from the general population (mean age 51.0 years; 60% women) were included in the study. GI symptoms were assessed with The Gastrointestinal Symptom Rating Scale-irritable bowel syndrome (GSRS-IBS), level of anxiety and depression with The Hospital Anxiety and Depression Scale (HADS) and stress-proneness with Perceived Stress Questionnaire. Over a ten year period, all visits in primary care were retrospectively recorded in order to identify functional GI disorders. RESULTS: In subjects with low total HADS-score, there were no significant differences in GI-symptoms between patients and controls (GSRS-IBS 7.0 vs 6.5, P = 0.513). In the patients with bipolar disorder there were significant correlations between all GSRS and HADS subscores for all symptom clusters except for "constipation" and "reflux". Factors associated to GI symptoms in the patient group were female sex (adjusted OR = 2.37, 95%CI: 1.07-5.24) and high HADS-Depression score (adjusted OR = 3.64, 95%CI: 1.07-12.4). These patients had also significantly more visits for IBS than patients with low HADS-Depression scores (29% vs 8%, P = 0.008). However, there was no significant differences in consulting behaviour for functional GI disorders between patients and controls (25% vs 17%, P = 0.108). CONCLUSION: Female patients and patients with high HADS depression score reported significantly more GI symptoms, whereas patients with low HADS scores did not differ from control subjects.

Relative hypocortisolism is associated with obesity and the metabolic syndrome in recurrent affective disorders.

BACKGROUND: Cardiovascular disease (CVD) is one of the main causes of excess deaths in affective disorders. Affective disorders are associated with increased frequencies of CVD risk-factors such as obesity, dyslipidemia, and metabolic syndrome. Stress-induced chronic cortisol excess has been suggested to promote obesity and metabolic syndrome. Chronic stress with frequent or persisting hypothalamic-pituitary-adrenal-axis (HPA-axis) hyperactivity may, over time, lead to a state of low HPA-axis activity, also denoted hypocortisolism. A low-dose weight-adjusted dexamethasone-suppression-test (DST) is considered to be a sensitive measure of hypocortisolism. METHODS: 245 patients with recurrent depression or bipolar disorder and 258 controls participated in a low-dose DST and were also examined with regard to metabolic status. RESULTS: Patients with hypocortisolism (low post-DST cortisol) compared with patients without hypocortisolism (normal or high post-DST cortisol) exhibited increased odds ratios (OR) for obesity (OR=4.0), overweight (OR=4.0), large waist (OR=2.7), high LDL (OR=4.2), low HDL (OR=2.4), high LDL/HDL ratio (OR=3.3), high TC/HDL ratio (OR=3.4) and metabolic syndrome (OR=2.0). A similar pattern but less pronounced was also found in the control sample. LIMITATIONS: The cross sectional study design and absence of analyses addressing lifestyle factors. CONCLUSIONS: Our findings suggest that a substantial portion of the metabolic disorders and cardiovascular risk factors seen in recurrent affective disorders are found among individuals exhibiting hypocortisolism. This might indicate that long-term stress is a central contributor to metabolic abnormalities and CVD mortality in recurrent affective disorders.

Hypothalamus-Pituitary-Adrenal Axis Hypersuppression Is Associated with Gastrointestinal Symptoms in Major Depression.

BACKGROUND/AIMS: Gastrointestinal symptoms and hypothalamus-pituitary-adrenal (HPA) axis dysfunction are frequently observed in patients with major depression. The primary aim of the study was to investigate the relationship between HPA-axis function and self-perceived functional gastrointestinal symptoms in major depression. METHODS: Patients with major depression (n = 73) and controls representative of the general population (n = 146) underwent a weight adjusted very low dose dexamethasone suppression test (DST). Patients and controls completed the gastrointestinal symptom rating scale-iritable bowel syndrome (GSRS-IBS) and the hospital anxiety depression scale. Medical records of the patients were screened over a ten year period for functional gastrointestinal disorder and pain conditions. RESULTS: Patients with high GSRS-IBS scores (above median) exhibited HPA-axis hypersuppression more often than controls (defined by the lowest 10% cutoff of the post-DST cortisol values among controls, adjusted OR 7.25, CI 1.97-26.7) whereas patients with low GSRS-IBS scores did not differ from controls concerning their post-DST cortisol values. Patients who had consulted primary care for functional gastrointestinal disorder (P = 0.039), lumbago (P = 0.006) and chronic multifocal pain (P = 0.057) also exhibited an increased frequency of hypersuppression. CONCLUSIONS: HPA-axis hypersuppression is associated with functional gastrointestinal symptoms in patients with major depression.

Relative hypo- and hypercortisolism are both associated with depression and lower quality of life in bipolar disorder: a cross-sectional study.

BACKGROUND: Depression in unipolar and bipolar disorders is associated with hypothalamic-pituitary-adrenal-axis (HPA-axis) hyperactivity. Also, unipolar disorder has recently been shown to exhibit HPA-axis hypoactivity. We studied for the first time how HPA-axis hypo- and hyperactivity relate to depression and disease burden in bipolar disorder. We were interested in studying hypocortisolism; characterized by increased HPA-axis negative feedback sensitivity and lower basal cortisol levels together with the opposite HPA-axis regulatory pattern of hypercortisolism. METHODS: This cross-sectional study includes 145 type 1 and 2 bipolar outpatients and 145 matched controls. A dexamethasone-suppression-test (DST) measures the negative feedback sensitivity and a weight-adjusted very-low-dose DST was employed, which is sensitive in identifying hypocortisolism and hypercortisolism. The 25th and 75th percentiles of control post-DST values were used as cut-offs identifying patients exhibiting relative hypo-, and hypercortisolism. Self-report questionnaires were employed: Beck-Depression-Inventory (BDI), Montgomery-Åsberg-Depression-Rating-Scale (MADRS-S), World-Health-Organization-Quality-of-Life-Assessment-100 and Global-Assessment-of-Functioning. RESULTS: Patients exhibiting relative hypocortisolism expectedly exhibited lowered basal cortisol levels (p = 0.046). Patients exhibiting relative hypercortisolism expectedly exhibited elevated basal levels (p<0.001). Patients exhibiting relative hypocortisolism showed 1.9-2.0 (BDI, p = 0.017, MADRS-S, p = 0.37) and 6.0 (p<0.001) times increased frequencies of depression and low overall life quality compared with patients exhibiting mid post-DST values (eucortisolism). Adjusted Odds Ratios (OR:s) for depression ranged from 3.8-4.1 (BDI, p = 0.006, MADRS-S, p = 0.011) and was 23.4 (p<0.001) for life quality. Patients exhibiting relative hypercortisolism showed 1.9-2.4 (BDI, p = 0.017, MADRS-S, p = 0.003) and 4.7 (p<0.001) times higher frequencies of depression and low overall life quality compared with patients exhibiting eucortisolism. Adjusted OR:s for depression ranged from 2.2-2.7 (BDI, p = 0.068, MADRS-S, p = 0.045) and was 6.3 (p = 0.008) for life quality. LIMITATIONS: The cross-sectional design and lack of pre-established reference values of the DST employed. CONCLUSIONS: Relative hypocortisolism and relative hypercortisolism were associated with depression and lower life quality, providing novel insights into the detrimental role of stress in bipolar disorder.

Shorter telomere length is linked to brain atrophy and white matter hyperintensities.

BACKGROUND: leukocyte telomere length (TL) is considered a marker of biological aging. Several studies have investigated the link between leukocyte TL and aging-associated functional attributes of the brain, but no prior study has investigated whether TL can be linked to brain atrophy and white matter hyperintensities (WMHs); two prominent structural manifestations of brain aging. METHODS: we investigated whether leukocyte TL was related to brain atrophy and WMHs in a sample of 102 non-demented individuals aged 64-75 years. RESULTS: shorter TL was related to greater degree of subcortical atrophy (ß = -0.217, P = 0.034), but not to cortical atrophy. Furthermore, TL was 371 bp shorter (P = 0.041) in participants exhibiting subcortical WMHs, and 552 bp shorter (P = 0.009) in older participants exhibiting periventricular WMHs. CONCLUSION: this study provides the first evidence of leukocyte TL being associated with cerebral subcortical atrophy and WMHs, lending further support to the concept of TL as a marker of biological aging, and in particular that of the aging brain.

Longer leukocyte telomere length is associated with smaller hippocampal volume among non-demented APOE ε3/ε3 subjects.

Telomere length shortens with cellular division, and leukocyte telomere length is used as a marker for systemic telomere length. The hippocampus hosts adult neurogenesis and is an important structure for episodic memory, and carriers of the apolipoprotein E ε4 allele exhibit higher hippocampal atrophy rates and differing telomere dynamics compared with non-carriers. The authors investigated whether leukocyte telomere length was associated with hippocampal volume in 57 cognitively intact subjects (29 ε3/ε3 carriers; 28 ε4 carriers) aged 49-79 yr. Leukocyte telomere length correlated inversely with left (r(s) = -0.465; p = 0.011), right (r(s) = -0.414; p = 0.025), and total hippocampus volume (r(s) = -0.519; p = 0.004) among APOE ε3/ε3 carriers, but not among ε4 carriers. However, the ε4 carriers fit with the general correlation pattern exhibited by the ε3/ε3 carriers, as ε4 carriers on average had longer telomeres and smaller hippocampi compared with ε3/ε3 carriers. The relationship observed can be interpreted as long telomeres representing a history of relatively low cellular proliferation, reflected in smaller hippocampal volumes. The results support the potential of leukocyte telomere length being used as a biomarker for tapping functional and structural processes of the aging brain.

Short telomeres in depression and the general population are associated with a hypocortisolemic state.

BACKGROUND: The hypothalamic-pituitary-adrenal (HPA) axis plays a central role in stress regulation, and leukocyte telomere length (TL) has been suggested to represent a cumulative measure of stress. Depression is intimately related with stress and frequently exhibits a dysregulated HPA axis. We aimed to study the relationships between TL and biological and psychological facets of stress in recurrent major depressive disorder and controls. METHODS: Leukocyte TL was measured in 91 subjects with recurrent major depressive disorder and 451 control subjects. Stress was assessed from both a biological perspective, by assessing HPA axis function with a weight-adjusted very-low-dose dexamethasone suppression test (DST), and a psychological perspective, with self-report questionnaires. RESULTS: TL was shorter among patients compared with control subjects (277 base pairs, p = .001). Overall, short TL was associated with a hypocortisolemic state (low post-DST cortisol and high percentage of cortisol reduction after the DST) among both patients and control subjects but more pronounced among patients. This state, which was overrepresented among patients, was characterized by high familial loading of affective disorders among patients (p = .001) and high C-reactive protein levels among control subjects (p = .040). TL was also inversely associated with stress measured with the Perceived Stress Questionnaire (r(s) = -.258, p = .003). CONCLUSIONS: Short TL is associated with depression and hypocortisolism. Because hypocortisolism has been shown to develop from chronic stress exposure, our findings corroborate the concept of TL as a cumulative measure of stress and provide novel insights into the detrimental role of stress in depressive illness and the general population.

APOE ε4 is associated with longer telomeres, and longer telomeres among ε4 carriers predicts worse episodic memory.

Both leukocyte telomere length and the apolipoprotein ε4 allele have been associated with mortality, cardiovascular disease, cognition, and dementia. The authors investigated whether leukocyte telomere length was associated with APOE genotype or cognitive abilities in the context of APOE genotype. The setting for this cross-sectional study was 427 nondemented individuals aged 41-81 yr. The authors found that ε4 carriers overall exhibited significantly longer telomeres compared with non-carriers (difference of 268 bp, p = 0.001). This difference was greatest at the lower limit of the age span and nonsignificant at the upper limit, which translated into a significantly higher telomere attrition rate (p = 0.049) among ε4 carriers (37 bp/years) compared with non-carriers (21 bp/year). Further, longer telomeres among ε4 carriers significantly predicted worse performance on episodic memory tasks. No significant associations were found on tasks tapping semantic and visuospatial ability, or among ε3/ε3 carriers. In conclusion, APOE ε4 carriers had longer telomeres compared with non-carriers, but higher rate of attrition. Among them, longer telomeres predicted worse performance on episodic memory tasks. These observations suggest that the ε4 allele is associated with abnormal cell turnover of functional and possibly clinical significance.

The relationship between the val158met catechol-O-methyltransferase (COMT) polymorphism and irritable bowel syndrome.

BACKGROUND: The catechol-O-methyltransferase (COMT) enzyme has a key function in the degradation of catecholamines and a functional polymorphism is val158met. The val/val genotype results in a three to fourfold higher enzymatic activity compared with the met/met genotype, with the val/met genotype exhibiting intermediate activity. Since pain syndromes as well as anxiety and depression are associated to low and high COMT activity respectively and these conditions are all associated with irritable bowel syndrome (IBS) we wanted for the first time to explore the relationship between the polymorphism and IBS. METHODOLOGY/PRINCIPAL FINDINGS: 867 subjects (445 women) representative of the general population and 70 consecutively sampled patients with IBS (61 women) were genotyped for the val158met polymorphism and the IBS patients filled out the Hospital-Anxiety-and-Depression-Scale (HADS) questionnaire, and an IBS symptom diary. RESULTS: There was a significantly higher occurrence of the val/val genotype in patients compared with controls (30% vs 20%; Chi(2) (1) 3.98; p = 0.046) and a trend toward a lower occurrence of the val/met genotype in IBS patients compared with controls (39% vs 49%; Chi(2) (1) 2.89; p = 0.089). Within the IBS patients the val/val carriers exhibited significantly increased bowel frequency (2.6 vs 1.8 stools per day; Chi(2) (1) 5.3; p = 0.03) and a smaller proportion of stools with incomplete defecation (41% vs 68%; Chi(2) (1) 4.3; p = 0.04) compared with the rest (val/met+met/met carriers). The val/val carriers also showed a trend for a smaller proportion of hard stools (0% vs 15%; Chi(2) (1) 3.2; p = 0.08) and a higher frequency of postprandial defecation (26% vs 21%; Chi(2) (1) 3.0; p = 0.08). CONCLUSIONS/SIGNIFICANCE: In this study we found an association between the val/val genotype of the val158met COMT gene and IBS as well as to specific IBS related bowel pattern in IBS patients.