Leptin plasma concentrations increase during antidepressant treatment with amitriptyline and mirtazapine, but not paroxetine and venlafaxine: leptin resistance mediated by antihistaminergic activity?

Treatment with several psychopharmacological agents has been associated with increased leptin plasma concentrations. We measured leptin plasma concentrations in 76 adult depressed patients after a 6-day washout phase and again after 35 days of treatment with amitriptyline or paroxetine, as well as in 73 depressed patients after 28 days of treatment with either mirtazapine or venlafaxine. Leptin plasma concentrations increased during treatment with amitriptyline and mirtazapine, even after controlling for increased body mass index and irrespective of response to treatment [14.5 (13.8) vs 20.3 (18.7) ng/mL, and 12.2 (15.8) vs 14.4 (16.5) ng/mL in the 2 cohorts, respectively]. In contrast, paroxetine and venlafaxine treatment was not associated with changes in leptin plasma concentrations [14.8 (12.0) vs 13.6 (10.6); 15.9 (17.3) vs 13.5 (14.6) ng/mL] nor with weight gain. We conclude that treatment with amitriptyline or mirtazapine is associated with an increase in leptin secretion beyond change in weight. Thus, high leptin levels apparently are ineffective in the control of weight gain, indicating leptin resistance. Leptin resistance may be mediated by an antihistaminergic effect on hypothalamic nuclei integrating signals relevant for energy balance.

Antidepressant treatment with mirtazapine, but not venlafaxine, lowers cortisol concentrations in saliva: a randomised open trial.

Lowering the concentrations of free cortisol in depressed patients may be an important prerequisite to prevent glucocorticoid-related sequelae of depression. We tested the hypothesis that the hypothalamus-pituitary-adrenal (HPA) system-dampening effects of venlafaxine and mirtazapine differ. We compared the course of morning (08.00h) and afternoon saliva cortisol (16.00h) in 42 mirtazapine- and 45 venlafaxine-treated depressed patients during a 1-week wash-out and a 4-week treatment period in a randomised open trial. Mirtazapine lowered afternoon cortisol from week 1 to 4. In contrast, during the course of the entire treatment period, venlafaxine did not attenuate saliva cortisol concentrations. Treatment effects of mirtazapine on cortisol concentrations did not differ in remitters and non-remitters to treatment. High baseline cortisol concentrations, on the other hand, were related to an unfavourable course during venlafaxine treatment and patients remitting during venlafaxine treatment had significantly lower afternoon cortisol concentrations in saliva, when compared to non-remitting patients. Thus, mirtazapine and venlafaxine show different effects on HPA system activity as measured by saliva cortisol. This may be of relevance with regard to physical sequelae of depression.

Resistin and adiponectin in major depression: the association with free cortisol and effects of antidepressant treatment.

Major depression is associated with an increased risk for myocardial infarction. Adipokines have been shown to link obesity with metabolic disturbances. Based on this finding the present study was designed to investigate the effect of antidepressive treatment with either amitriptyline or paroxetine on circulating concentrations of resistin and adiponectin in depressed patients, and to establish, whether these adipokines are associated with the activation of the hypothalamic-pituitary-adrenal (HPA)-system. Thirty-seven depressed in-patients were treated in a double-blind, randomized protocol with either amitriptyline or paroxetine over a period of five weeks. After six drug free days blood was drawn on day 1 and again 36 days after antidepressive treatment for the measurement of resistin and adiponectin, fasting glucose and insulin concentrations. For quantification of free cortisol levels saliva was obtained daily at 0800 hours during weeks 1 and 5. While resistin concentrations decreased in patients remitting under amitriptyline and paroxetine (p<0.03), no changes were observed in non-remitters. At baseline, though not during treatment, circulating resistin concentrations correlated positively with free cortisol levels and with BMI (p<0.01). Adiponectin levels, however, did not change during treatment and were not associated with free cortisol concentrations but were instead positively related to QUICKI (p<0.03). In conclusion, the present data revealed resistin but not adiponectin to be related to free cortisol concentrations and to decline in remitters to antidepressive treatment.

Metabolic changes in elderly patients with major depression: evidence for increased accumulation of visceral fat at follow-up.

The accumulation of visceral fat is promoted by a specific endocrine syndrome, which is similarly found in major depression. The aim of this study was to investigate whether visceral fat depots increase in depressed patients during a follow-up period explaining the increased risk for cardiovascular disorders. Intraabdominal fat was measured in 29 depressed patients and 17 controls by computer tomography at the level of lumbar vertebra 4. In patients fat measurements were done initially during a major depressive episode and again after a follow-up period of 14 months; in controls the mean time interval between measurements was 28 months. In both groups, saliva was taken at 800 h over a period of seven days prior to each CT for the estimation of free cortisol. In patients only, an oral glucose tolerance test was also carried out. Compared to controls hyper- and normocortisolemic depressed patients showed a larger accumulation of visceral fat mass over time (hypercort.:132.0 +/- 45 vs. 144.7 +/- 47 cm(2), p = 0.07; normocort.: 115.5 +/- 53 vs. 135.0 +/- 51 cm(2), p = 0.002; controls: 130.1 +/- 66 vs. 137.3 +/- 76 cm(2), p = 0.4), despite similar weight gain (hypercort.: 2.1 +/- 5 kg, normocort.: 1.7 +/- 5 kg and controls: 2.3 +/- 4 kg). Further, normocortisolemic patients showed a trend for an higher percentile increase in visceral fat accumulation than controls (23.9 +/- 27 vs. 5.8 +/- 28%, p = 0.07). At follow-up, free cortisol concentrations were still above normal in patients who had been hypercortisolemic at first assessment (35.0 +/- 8 vs. 28.8 +/- 18 nmol/l, p = 0.1). Fasting and 2 h glucose concentrations were higher in hypercortisolemic compared to normocortisolemic patients at the index examination (6.2 +/- 1.1 vs. 5.0 +/- 0.05 mmol/l, p = 0.02; 11.5 +/- 2.7 vs. 7.8 +/- 1.9 mmol/l, p = 0.01). The larger proportion of visceral fat accumulation in patients may constitute a link for explaining the increased cardiovascular mortality in patients suffering from major depression.

Effect of ambulatory blood pressure measurement on sleep in patients with a major depressive episode.

BACKGROUND: To assess the effects of ambulatory blood pressure measurement (ABPM) upon sleep in mentally depressed patients with near absence of deep (stage 3 and 4) sleep. METHODS: Twelve depressed patients aged 50.5+/-13.5 (21-item Hamilton Depression Rating Scale: 23.8+/-5.1) were studied on three consecutive nights in the sleep laboratory. In a random order, blood pressure was measured with a portable device over 24 h on either day 2 or 3. Polysomnographic data were analysed according to the criteria of Rechtschaffen and Kales. RESULTS: Compared to the control night, there was a significant increase of awakenings during the ABPM night. However, total sleeping time as well as sleep efficiency remained unchanged. Percentage of nocturnal decrease in both systolic and diastolic blood pressure was unrelated to the number of arousals. CONCLUSION: In depressed patients with severe disturbances of sleep architecture, ABPM did not lead to a prolongation of time awake or decrease in sleep efficiency.

Serum lipoproteins improve after successful pharmacologic antidepressant treatment: a randomized open-label prospective trial.

OBJECTIVE: Despite reports of lower plasma cholesterol in depressed patients, major depressive disorder has been shown to increase cardiovascular risk. Our objective was to study the composition of lipoproteins in depressed patients and controls and to examine the effects of pharmacologic treatment and treatment response on lipoprotein composition. METHOD: Lipoprotein composition was analyzed in 65 adult inpatients at a university psychiatric hospital in Germany with DSM-IV major depressive disorder and 33 healthy controls (recruited via newspaper and radio ads) matched for age and sex. After the cross-sectional study phase, the patients were randomized in an open-label prospective trial to treatment with either mirtazapine or venlafaxine. Lipoproteins were reanalyzed after 4 weeks of treatment. Main outcome measures were total cholesterol, the low-density lipoprotein (LDL) to high-density lipoprotein (HDL) cholesterol ratio, and the LDL triglycerides to apolipoprotein B ratio. Secondary outcome measures were total triglycerides, HDL and LDL cholesterol levels, and apolipoproteins A1 and B levels. Comparisons were made between the 2 drug groups and between remitters and nonremitters as measured by the 21-item Hamilton Depression Rating Scale. The study was conducted from April 2003 through December 2007. RESULTS: Total cholesterol at baseline was lower in patients than in controls (mean ± SD = 4.99 ± 0.98 mmol/L vs 5.63 ± 1.01 mmol/L; P = .003), with significantly lower HDL cholesterol (P < .001) and LDL cholesterol (P = .03) in patients. However, the ratio of LDL triglycerides to apolipoprotein B, an index of size and atherogenic potential of LDL particles, was higher in depressed subjects (mean ± SD = 0.46 ± 0.14 mmol/g vs 0.38 ± 0.09 mmol/g; P = .002). Irrespective of treatment allocation, we found significant improvement of cardiovascular risk parameters in remitters but found deterioration in nonresponders. The LDL cholesterol mean change from baseline (remitters vs partial responders vs nonresponders) was -0.06 mmol/L versus +0.39 mmol/L versus +0.56 mmol/L (P = .014); the mean change in LDL/HDL cholesterol ratio was -0.50 versus +0.14 versus +0.80 (P = .002); and the mean change in the LDL triglycerides per apolipoprotein B ratio was -0.01 versus -0.01 versus +0.08 (P = .045). No drug-specific changes in lipid concentrations during treatment were observed except for total cholesterol (venlafaxine group mean = -0.02 mmol/L and mirtazapine group mean = +0.37 mmol/L; P = .033). CONCLUSIONS: In depressed patients, lipoprotein structure is changed toward LDL particles with a higher atherogenic potential. Remission from depression is associated with an improvement of the LDL/HDL cholesterol ratio, shifting lipoproteins toward a less atherogenic composition. Our findings should be confirmed in a larger study, as they have relevance for both researchers and clinicians. TRIAL REGISTRATION: German Clinical Trial Registry Identifier: DRKS00000008.

Improved insulin sensitivity in 80 nondiabetic patients with MDD after clinical remission in a double-blind, randomized trial of amitriptyline and paroxetine.

OBJECTIVE: There is substantial evidence that depression constitutes a risk factor for type 2 diabetes mellitus. A recent study has shown that high salivary cortisol levels are associated with decreased insulin sensitivity in unmedicated, depressed patients. Further, antidepressive treatment might have differential effects on hypothalamus-pituitary-adrenal (HPA) system activity. Therefore, the aim of the present study was to examine whether insulin sensitivity improves during anti-depressive treatment in depressed patients with declining HPA system activity. METHOD: Eighty inpatients with an episode of major depressive disorder (DSM-IV criteria) were treated in a double-blind, randomized protocol with either amitriptyline or paroxetine over a period of 5 weeks. After 6 drug-free days, an oral glucose tolerance test was performed on day 1 and again 35 days after antidepressive treatment. For quantification of free cortisol levels, saliva was obtained daily at 8:00 a.m. during weeks -1 (washout) and 5. The study was conducted from May 2005 to December 2005. RESULTS: The insulin sensitivity index(Matsuda) increased in only those patients who remitted from major depressive disorder as a result of treatment with either antidepressant (F = 7.0, df = 1,74; p < .01), while correcting for body mass index. Further, cortisol concentrations declined in remitters and responders to amitriptyline (F = 2.1, df = 1,70; p < .05), but not in any other subgroup. CONCLUSION: Successful antidepressive treatment with either a selective serotonin reuptake inhibitor or a tricyclic substance increases the sensitivity to insulin in nondiabetic depressed patients. The herein presented longitudinal data do not exclude the HPA system as a major contributor to insulin resistance in depressed patients, but underscore the assumption of additional factors.

Activity of the hypothalamus-pituitary-adrenal system and oral glucose tolerance in depressed patients.

We hypothesized that the activity of the hypothalamus-pituitary-adrenal system in depressed patients is related to oral glucose tolerance. In 70 moderately depressed inpatients, we measured morning saliva cortisol for 6 days and assessed oral glucose tolerance. We found glucose concentrations to be positively associated with mean morning cortisol concentrations (F3,236 = 2.86, p < 0.05). Also, the ISI, a measure of insulin receptor sensitivity, was negatively associated with mean morning cortisol concentrations (r = -0.25, p < 0.04). These findings support the hypothesis that hypercortisolemia may lead to disturbed glucose utilization in depressed patients.

Hypercortisolemic depression is associated with increased intra-abdominal fat.

OBJECTIVE: Similar to patients with a metabolic syndrome, patients with major depression are at increased risk of developing cardiovascular disorders. Interestingly, both disorders share a specific endocrine syndrome that promotes the accumulation of visceral fat, which again is considered a marker of increased cardiovascular morbidity and mortality. METHODS: Intra-abdominal fat was measured in 22 postmenopausal depressed women and 23 age-matched healthy women by computer tomography at the level of lumbar vertebrae 1 (L1) and 4 (L4). Saliva was taken in patients and control subjects at 08:00 hours over a period of 7 drug-free days for the measurement of free cortisol. In patients only we performed an oral glucose tolerance test. RESULTS: Compared with control subjects, depressed patients with elevated free cortisol concentrations showed similar visceral fat depots at L1 (113.0 +/- 41.6 vs. 94.3 +/- 53.2 cm(2)). Hypercortisolemic depressed patients also showed greater fat depots in this area (74.5 +/- 55.5 cm(2), p =.04) than the normocortisolemic patients. However, a comparison of all patients with control subjects revealed no difference in fat accumulation at either L1 or L4. Finally, glucose concentrations during the glucose tolerance test were higher in hypercortisolemic than in normocortisolemic patients, whereas their insulin levels showed only a tendency toward being increased. CONCLUSIONS: Hypercortisolemic depressed patients suffer from resistance to insulin and increased visceral fat. The fact that hypercortisolemia reverses depression-related fat loss, particularly in the visceral area, might partially explain why major depression can be considered a risk factor for cardiovascular disorders.

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.