Changes in weight during treatment for depression

Endocrine disruptors and obesity

The increasing incidence of obesity is a serious global public health challenge. Although the obesity epidemic is largely fueled by poor nutrition and lack of exercise, certain chemicals have been shown to potentially have a role in its aetiology. A substantial body of evidence suggests that a subclass of endocrine-disrupting chemicals (EDCs), which interfere with endocrine signalling, can disrupt hormonally regulated metabolic processes, especially if exposure occurs during early development. These chemicals, so-called 'obesogens' might predispose some individuals to gain weight despite their efforts to limit caloric intake and increase levels of physical activity. This Review discusses the role of EDCs in the obesity epidemic, the latest research on the obesogen concept, epidemiological and experimental findings on obesogens, and their modes of action. The research reviewed here provides knowledge that health scientists can use to inform their research and decision-making processes.

Amitriptyline versus placebo for major depressive disorder

BACKGROUND

Amitriptyline is a tricyclic antidepressant that was synthesised in 1960 and introduced as early as 1961 in the USA, but is still regularly used. It has also been frequently used as an active comparator in trials on newer antidepressants and can therefore be called a 'benchmark' antidepressant. However, its efficacy and safety compared to placebo in the treatment of major depression has not been assessed in a systematic review and meta-analysis.

OBJECTIVES

To assess the effects of amitriptyline compared to placebo or no treatment for major depressive disorder in adults.

SEARCH METHODS

We searched the Cochrane Depression, Anxiety and Neurosis Group's Specialised Register (CCDANCTR-Studies and CCDANCTR-References) to August 2012. This register contains relevant randomised controlled trials from: The Cochrane Library (all years), EMBASE (1974 to date), MEDLINE (1950 to date) and PsycINFO (1967 to date). The reference lists of reports of all included studies were screened and manufacturers of amitriptyline contacted for details of additional studies.

SELECTION CRITERIA

All randomised controlled trials (RCTs) comparing amitriptyline with placebo or no treatment in patients with major depressive disorder as diagnosed by operationalised criteria.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. For dichotomous data, we calculated the odds ratio (OR) with 95% confidence intervals (CI). We analysed continuous data using standardised mean differences (with 95% CI). We used a random-effects model throughout.

MAIN RESULTS

The review includes 39 trials with a total of 3509 participants. Study duration ranged between three and 12 weeks. Amitriptyline was significantly more effective than placebo in achieving acute response (18 RCTs, n = 1987, OR 2.67, 95% CI 2.21 to 3.23). Significantly fewer participants allocated to amitriptyline than to placebo withdrew from trials due to inefficacy of treatment (19 RCTs, n = 2017, OR 0.20, 95% CI 0.14 to 0.28), but more amitriptyline-treated participants withdrew due to side effects (19 RCTs, n = 2174, OR 4.15, 95% CI 2.71 to 6.35). Amitriptyline also caused more anticholinergic side effects, tachycardia, dizziness, nervousness, sedation, tremor, dyspepsia, sedation, sexual dysfunction and weight gain. In subgroup and meta-regression analyses the results of the primary outcome were robust towards publication year (1971 to 1997), mean participant age at baseline, mean amitriptyline dose, study duration in weeks, pharmaceutical sponsor, inpatient versus outpatient setting and two-arm versus three-arm design. However, higher severity at baseline was associated with higher superiority of amitriptyline (P = 0.02), while higher responder rates in the placebo groups were associated with lower superiority of amitriptyline (P = 0.05). The results of the primary outcome were rather homogeneous, reflecting comparability of the trials. However, methods of randomisation, allocation concealment and blinding were usually poorly reported. Not all studies used intention-to-treat analyses and in many of them standard deviations were not reported and often had to be imputed. Funnel plots suggested a possible publication bias, but the trim and fill method did not change the overall effect size much (seven adjusted studies, OR 2.64, 95% CI 2.24 to 3.10).

AUTHORS' CONCLUSIONS

Amitriptyline is an efficacious antidepressant drug. It is, however, also associated with a number of side effects. Degree of placebo response and severity of depression at baseline may moderate drug-placebo efficacy differences.

The association between conventional antidepressants and the metabolic syndrome: a review of the evidence and clinical implications

Major depressive disorder is a prevalent recurrent medical syndrome associated with inter-episodic dysfunction. The metabolic syndrome is comprised of several established risk factors for cardiovascular disease (i.e. abdominal obesity, dyslipidaemia, dysglycaemia and hypertension). The criterion items of the metabolic syndrome collectively represent a multi-dimensional risk factor for cardiovascular disease and type 2 diabetes mellitus. Extant evidence indicates that both major depressive disorder and the metabolic syndrome, albeit distinct, often co-occur and are possibly subserved by overlapping pathophysiology and causative mechanisms. Conventional antidepressants exert variable effects on constituent elements of the metabolic syndrome, inviting the need for careful consideration prior to treatment selection and sequencing. Initiating and maintaining antidepressant therapy should include routine surveillance for clinical and/or biochemical evidence suggestive of the metabolic syndrome.

Antidepressivos e alterações no peso corporal

A depressão é uma doença que pode levar a mudanças no peso, influenciadas por fatores específicos da doença, como alterações no apetite e na atividade física, ou pelos antidepressivos. Este artigo objetiva analisar os estudos que descrevem os efeitos dos antidepressivos em alterações do peso corporal. Realizou-se uma pesquisa nas bases de dados Medline, Lilacs e Cochrane, utilizando as palavras chaves " antidepressivo" e " peso" . Foram selecionados os estudos que analisaram o tema em pacientes depressivos, priorizando-se aqueles relacionados às drogas mais utilizadas nos serviços de saúde no Brasil. A análise dos estudos indicou que a mudança de peso atribuída ao tratamento com antidepressivos apresenta resultados ainda controversos, sendo influenciada por fatores como o tempo de uso e a dosagem do medicamento, estudos com poder limitado, entre outros. Assim, estudos com maior poder, tendo como foco a ação das drogas antidepressivas nas alterações do peso corporal em pacientes depressivos, ainda são necessários.

Anxiety and depressive disorders in college youth

Fear and anxiety are common experiences throughout childhood and adolescence. Anxiety disorders, along with depression and dysthymia, are characterized as internalizing disorders; they stand in distinction from the externalizing disorders representing such conditions as oppositional-defiant disorder and conduct disorder. Clinicians evaluating anxiety disorders in college youth face the task of differentiating normal, transient, developmentally appropriate expression of anxiety from pathologic states of anxiety. The developmental course of anxiety and depression, its appropriateness, and its boundaries are areas of research and interest. A wide clinical perspective is necessary to effectively engage the assessment process. The treatment of anxiety and depression in youth is ideally multi-modal, involving medication, psychotherapy, and psychosocial interventions. This article focuses on assessment and treatment of anxiety and depression. These are presented separately, although areas of overlap often are encountered in practice.

Amitriptyline v. the rest: still the leading antidepressant after 40 years of randomised controlled trials

BACKGROUND

Tricyclic antidepressants have similar efficacy and slightly lower tolerability than selective serotonin reuptake inhibitors (SSRIs). However, there are no systematic reviews assessing amitriptyline, the reference tricyclic drug, v. other tricyclics and SSRIs directly.

AIMS

To review the tolerability and efficacy of amitriptyline in the management of depression.

METHOD

A systematic review of randomised controlled trials (RCTs) comparing amitriptyline with other tricyclics/heterocyclics or with an SSRI.

RESULTS

We reviewed 186 RCTs. The overall estimate of the efficacy of amitriptyline revealed a standardised mean difference of 0.147 (95% CI 0.05-0.243), significantly favouring amitriptyline. The overall OR for dropping out was 0.99 (95% CI 0.91-1.08) and that for side-effects was 0.62 (95% CI 0.54-0.70), favouring the control drugs. With drop-outs included as treatment failures, the estimate of the effectiveness of amitriptyline v. tricyclics/heterocyclics and SSRIs showed a 2.5% difference in the proportion of responders in favour of amitriptyline (number needed to treat 40, CI 21-694; OR 1.12 (95% CI 1.01-1.24)).

CONCLUSIONS

Amitriptyline is less well tolerated than tricyclics/heterocyclics and SSRIs, but slightly more patients treated on it recover than on alternative antidepressants.

Weight outcomes among antidepressant users in nursing facilities

OBJECTIVES

Depression is a common and treatable condition among nursing facility residents, with low body weight being a frequent concomitant concern. A common prescribing dictum is that older tricyclic antidepressants (TCAs) enhance appetite and may facilitate weight gain, while newer selective serotonin reuptake inhibitors (SSRIs) cause anorexia and resultant weight loss in older adults. Evidence is lacking on whether the small weight changes noted during short-term antidepressant efficacy trials translate into larger weight changes during prolonged treatment periods. Our main objective was to compare weight outcomes at 6 months among users of three different antidepressant groups with a control group of non-antidepressant users. A secondary objective was to determine whether antidepressant selection was associated with weight pattern before drug initiation, to capture possible prescribing bias that would affect study inferences.

DESIGN

Retrospective cohort design using the Minimum Data Set--Plus (MDS+).

SETTING

Kansas nursing facilities.

PARTICIPANTS

1,157 antidepressant users age 65 and older who started an antidepressant after admission and remained on the same single agent for at least 6 months, and 4,852 persons meeting the same inclusion/exclusion criteria but not receiving an antidepressant.

MEASUREMENTS

Antidepressant use was identified by drug code data and divided into four groups for analysis: TCAs, SSRIs, others, and none. (Amitriptyline and trazodone were excluded because of frequent use for nondepression purposes.) Rates of clinically important loss and gain (assigned for a 10% change from baseline weight or presence of the significant loss or gain markers on the 6-month MDS assessment) and mean weight changes were compared across the four groups. Regression models were used to control for age, gender, baseline weight, confounding comorbidity, and functional variables related to eating. Previous weight patterns (loss, gain, neither, or unknown) before antidepressant initiation were compared across drug groups.

RESULTS

Clinically important weight loss and gain occurred at 6 months in 14.8% and 14.4% of the sample, respectively. In unadjusted analyses, an increased likelihood of loss was found for users of SSRIs (Odds Ratio 1.57; CI 1.30, 1.90) and others (OR 1.89; CI 1.18, 3.03), compared with none. In logistic models accounting for potential confounding factors, however, SSRI use showed a modest association with gain (OR 1.31, CI 1.01, 1.70) and a trend toward a similarly modest association with loss (OR 1.28; CI 0.995, 1.64). TCA use was not associated with weight gain. When weight was examined as a continuous variable, all groups demonstrated a broad range of both loss and gain with mean-unadjusted weight changes < 3 pounds. Pairwise comparisons of adjusted differences in weight change at 6 months for SSRIs (mean loss of 1.6 pounds) and TCAs (mean gain of 0.4 pounds) were of marginal importance (P = .046) given the large sample size. No evidence was found for prescribing bias based on prior weight pattern.

CONCLUSIONS

TCAs do not facilitate weight gain more than other antidepressant groups and SSRIs are not associated disproportionately with weight loss when other important clinical variables are accounted for. Small but statistically significant differences in mean weight changes between groups are largely a reflection of large sample size rather than clinically important differences. Clinicians may wish to reconsider the widely held notions that TCAs facilitate weight gain and that SSRIs place depressed older nursing facility residents at disproportionate risk for weight loss.

Bodyweight change as an adverse effect of drug treatment. Mechanisms and management

A number of drugs are capable of changing bodyweight as an adverse effect of their therapeutic action. Bodyweight gain is more of a problem than bodyweight loss. As bodyweight gain during drug treatment for any kind of disease may be the reflection of improvement of the disease itself, we will try to separate these effects from those due to drug-induced alterations of the mechanisms regulating bodyweight. Bodyweight gain may jeopardise patient compliance to the prescribed regimen and it may pose health risks. The body mass index (BMI) is determined by dividing bodyweight in kilograms by height in metres squared. A BMI of > or = 27 kg/m2 warrants therapeutic action; nutritional counselling and programmed physical exercise can be used as a basis. In general, if basic therapeutic measures are unsuccessful at controlling bodyweight gain then a change of drug might help. Finally, an anoretic drug may serve to support dietary measures. However, safety and efficacy has been demonstrated for only a few anorectic drugs when used as an adjunct to caloric restriction in the treatment of drug-induced obesity. Bodyweight is determined by complex mechanisms regulating energy balance. A number of neurotransmitter systems acting in several hypothalamic nuclei are pivotal to the regulation of body fat stores. Most drugs that are capable of changing bodyweight interfere with these neurotransmitter systems. The increment is dependent on the type and dose of the drug concerned. Some antidepressant drugs induce bodyweight gain, which may amount to 20 kg over several months of treatment. Monoamine oxidase inhibitors appear to cause less bodyweight change than tricyclic antidepressants. Selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors cause bodyweight loss instead of bodyweight gain. Lithium may cause large increases in bodyweight. Generally speaking, the bodyweight change induced by antipsychotics is more often of clinical significance than the bodyweight change associated with the use of antidepressants. Again, the changes of bodyweight are dependent upon the type and dose of the antipsychotic drug involved. Although almost all antipsychotics induce bodyweight gain, molindone and loxapine appear to induce bodyweight loss. Anticonvulsants, especially valproic acid (sodium valproate) and carbamazepine, induce bodyweight gain in a considerable percentage of patients. Treatment with corticosteroids is associated with dose-dependent bodyweight gain in many patients. Corticosteroid-induced obesity aggravates other corticosteroid-associated health risks. Insulin therapy in diabetic patients usually increases bodyweight. Finally, sulphonurea derivatives, antineoplastic agents used for the treatment of breast cancer and several drugs used in migraine prophylaxis may cause bodyweight gain as well.

Drugs that cause weight gain

Among drugs which cause weight gain, the tricyclic antidepressant medications are a drug class producing persistent and problematic body weight gain in many treated patients. Major depressive illness is often associated with reductions in appetite and body weight, and treatment with antidepressants effectively restores mood, appetite and weight. However, a frequent complaint of patients treated with tricyclic drugs is of excessive and unwanted weight gain, often times resulting in medication noncompliance. The incidence of weight gain during acute and chronic treatment with different, frequently prescribed antidepressant drugs will be reviewed, as will the possible mechanisms by which such drugs alter caloric intake and expenditure, contributing to drug-induced weight gain.

Changes in the frequency distribution pattern of body weight in patients with major depression

To compare the frequency distribution of body weight of the depressed patients with that of a standard group and to evaluate the change in distribution during treatment, body weight was measured in 106 depressed inpatients with major depressive disorder as defined by DSM-III criteria both on admission and on discharge. The body weight distribution in the depressed patients skewed towards a high frequency of lower weights on admission but shifted to the normal pattern on discharge. In women, this tendency was more obvious and was statistically significant. The body weight distribution in the depressed patients with melancholia maintained high frequencies of lower body weight on discharge, while that in those without melancholia did not, suggesting that there could be a difference in the pattern of body weight distributions between those with endogenous and nonendogenous depression. Three tricyclic antidepressants examined (imipramine, clomipramine and desipramine) did not seem to have the side effect of pathological weight gain in the frequency distribution pattern.

Changes in appetite and weight during the pharmacological treatment of patients with panic disorder

Antidepressants reportedly increase appetite, carbohydrate craving and weight in some patients with depression and panic disorder. This paper presents the results of changes in appetite and weight in patients with panic disorder treated with imipramine, diazepam or placebo in a double-blind prospective study. Forty-four patients with panic disorder were randomly assigned imipramine, diazepam and placebo. The investigators monitored weight and the patients rated their appetite and cravings during the eight week study. No significant increases in weight or appetite were found in the patients with panic disorder patients.

Contrasts between symptoms of summer depression and winter depression

Epidemiological studies and studies of clinical populations suggest that there are primarily two opposite patterns of seasonally recurring depressions: summer depression and winter depression. In addition, there is preliminary evidence that the two seasonal types of depression may have opposite types of vegetative symptoms. In the present study, we prospectively monitored symptoms of depression in 30 patients with recurrent summer depression and 30 sex-matched patients with recurrent winter depression and compared the symptom profiles of the two groups. Consistent with predictions based on the earlier reports, we found that winter depressives were more likely to have atypical vegetative symptoms, with increased appetite, carbohydrate craving, weight gain and hypersomnia, and that summer depressives were more likely to have endogenous vegetative symptoms, with decreased appetite and insomnia. A cluster analysis performed on the patients' symptom profiles without reference to season of occurrence of their episodes separated 78% of the summer depressives and winter depressives from each other on the basis of their symptoms (chi 2 = 19.29, P less than 0.001).

Imipramine and weight gain during the treatment of recurrent depression

Weight change was examined in 128 depressed outpatients treated successfully with an average dose of 215 mg imipramine and then continued on that treatment regimen for 5 additional months, an average duration of over 33 weeks. More than half the patients experienced a change in weight of 5% or less and only 13.3% experienced a gain of greater than 10%. While males and females did not differ in their pattern of change during acute treatment, females experienced a greater percent change (P less than 0.06) and change in body mass index (P = 0.05) during continuation treatment. The clinical implications of these findings are discussed, especially with respect to the extreme group.

Depression, antidepressants, and body weight change

The excessive weight gain observed during treatment of depression with antidepressant medications is caused in part, at least in some persons, by reductions in resting metabolic rate. Such problematic weight gain appears unrelated to clinical recovery, weight change during the depressive episode, prior weight, or other related factors. Preliminary results suggest that increased energy efficiency (of about 16-24%) during treatment with tricyclic antidepressants could promote weight gain even in the absence of a change in caloric intake. This is not a property of all antidepressants, as demonstrated by the increase in metabolic rate and associated weight loss observed during treatment with the monocyclic antidepressant compound fluvoxamine. Should these serotonergic compounds continue to be effective antidepressants, they may be better accepted by patients, and their use help avoid medication noncompliance. In considering energy balance and weight change, our focus has been drawn to altered metabolic rate. Continuing studies do not suggest an effect of antidepressants on appetite, particularly the presence of "carbohydrate craving," either during treatment or during a depressive episode. Certainly, a notable preference for highly palatable foods (rich in fats and carbohydrates) occurs during the depressive episode, but not during treatment. These foods cannot be labeled carbohydrates.

Perception of appetite and weight change during treatment for depression

As part of the Pittsburgh Appetite Test, 50 depressed outpatients reported their perceptions of appetite and weight change prior to and during chronic treatment with imipramine and psychotherapy. At the end of 4 months, as a group, patients were significantly more conscious of what they were eating, and reported a significant change in the frequency of regular meal consumption. No group changes were noted in frequency of snacking or late night eating, although weight change during treatment and obesity status modified these responses. Clinical response was unrelated to eating behavior. Perception of weight change varied with treatment: a 5 pound weight gain became highly problematic during recovery compared to the depressive episode. The interaction of these factors and antidepressant-induced weight gain are discussed.

Antidepressant-induced weight gain: a comparison study of four medications

Body weight change was monitored in 73 hospitalized depressed patients treated with one of four antidepressants for 1 month. After a 2-week medication-free period, patients were randomly assigned to treatment with amitriptyline, nortriptyline, desipramine, or zimelidine. By the end of 1 month, treatment with all three tricyclic compounds promoted weight gain, with the greatest increase observed during amitriptyline treatment; less weight was gained by patients treated with nortriptyline and desipramine. In contrast, most patients treated with zimelidine showed no weight gain and, in many cases, demonstrated weight loss. Weight change during treatment was not associated with age, sex, severity of depression, obesity, weight loss during depression, or clinical response.

[Clinical study of 105 cases of isolated weight loss in internal medicine]

We arbitrarily define "isolated weight loss" as the loss of at least 10 p. 100 of body weight over less than one year, without any single cause being disclosed by questioning, physical examination and such paraclinical examinations as blood electrolytes, blood count and differential, routine dipstick urinalysis and X-ray of the chest. Among the 105 patients we studied, the causes of isolated weight loss were: (1) psychic disorders (chiefly depression) in 60 p. 100 of the cases; (2) a variety of organic diseases in 29 p. 100, including gastrointestinal diseases (8 p. 100), cardiovascular and respiratory diseases (6 p. 100), Horton's disease (4 p. 100), Portuguese amyloidosis (1 p. 100), unexplained inflammatory syndrome (1 p. 100), endocrine disease (hyperthyroidism, 4 p. 100) and intoxication with medicines, alcohol or heroin (5 p. 100); (3) no definite cause could be found in 11 p. 100 of the cases. We suggest a diagnostic approach involving a limited number of examinations, viz.: erythrocyte sedimentation rate, measurement of transaminases, gamma GT and alkaline phosphatase enzymes, abdominal ultrasonography and ultra-sensitive TSH assay. We consider it important to switch from useless paraclinical tests to the detection and management of psychic disorders. Weight loss is a frequent motive of consultation, but its diagnostic value is often misunderstood. The purpose of this study was to provide data for the artiological diagnosis of isolated weight loss--a relatively frequent problem in internal medicine.

Carbohydrate craving and increased appetite associated with antidepressant therapy

The symptom of carbohydrate craving and increased appetite (CHH) was studied in 180 outpatients receiving antidepressant treatment. One hundred and fifty-eight of these patients had a DSM-III diagnosis of panic disorder and 17, major depression. The incidence of CHH was similar in both diagnostic groups. Thus, antidepressant treatment is associated with CHH in patients with diagnoses, other than depression. Desipramine was least likely to induce CHH compared to imipramine, amitriptyline and doxepin. Most patients who developed CHH on imipramine no longer experienced this side effect when switched to desipramine. CHH was not more frequent among women and not associated with antidepressant dosage or treatment response. Histamine H-1 receptor blockade may be an important factor in the etiology of CHH.

Antihistaminic drugs increase feeding, while histidine suppresses feeding in rats

The present studies tested the hypothesis that histamine blockade stimulates appetite, while increases in histamine levels suppress appetite. Results show that the classical antihistamines cyproheptadine and promethazine both produced significant and long-lasting increases in food intake. Pronounced appetite stimulation was also seen following the administration of doxepin, the most potent antihistamine among the antidepressants. In contrast, administration of the histamine precursor histidine produced a profound suppression in food intake. The results thus suggest that an inverse relationship may exist between histamine and food intake.

Imipramine treatment and preference for sweets

Antidepressant-induced changes in food preference were investigated in a group of 40 depressed patients before and during treatment with imipramine. As part of a validated survey, the Pittsburgh Appetite Test, self-reported food preference was categorized by both nutrient and hedonic properties to define individual response. After 4 months of treatment, 14 patients (35%) expressed a clear desire for high-carbohydrate/high-fat foods with a sweet taste. Within this group, eight patients already preferred these foods while medication-free, while six subjects demonstrated a change in preference to these foods during treatment. The other 26 patients (65%) showed no consistent changes in food preference. These results suggest that while approximately one-third of imipramine-treated patients report a preference for sweets, only 15% actually developed this preference during treatment.

Antidepressants and weight gain

Weight gain is an often reported, but incompletely understood, side effect of many antidepressant medications. We will discuss the literature with respect to the following issues: weight gain as a pharmacological effect of antidepressants or as an effect of recovery from depression; the incidence of antidepressant-induced weight gain and possible reasons for individual variability in its occurrence; possible mechanisms of antidepressant-induced weight gain; and options for clinical management. Further elucidation of these issues may contribute to our understanding of the neurobiology of affective disorders and appetitive mechanisms.

Effects of chronic amitriptyline and desipramine on food intake and body weight in rats

Long-term treatment with tricyclic antidepressant drugs (TCAs) can induce excessive body weight gain in a significant proportion of patients. Such weight gains, which appear to be largely independent of clinical improvement, are in many cases severe enough to interfere with continuation of treatment. In efforts to model this effect in experimental animals, seven experiments were performed in which two commonly used TCAs, amitriptyline and desipramine, were administered chronically to rats. Despite manipulations of drug dosages (2.5 mg-17 mg/kg), route of administration (intraperitoneal, subcutaneous, oral; daily injections vs. continuous release from osmotic pumps), diet composition and palatability (regular Purina Chow pellets or powder with or without added high fat and high carbohydrate sources; high vs. low protein diets) and animal sex and housing conditions (single vs. group housing), chronic TCA treatment was never observed to increase daily food intake or rates of body weight gain. Desipramine treatment invariably caused decreased food intake and weight loss. Amitriptyline treatment either caused no change in food intake and body weight or slightly reduced levels in comparison to vehicle-treated controls. However, both amitriptyline- and desipramine-treated rats showed a potentiation of acute caloric intake after a single systemic injection of the glucoprivic agent 2-deoxy-D-glucose. These results are considered against the background of human clinical observations. Possible reasons for the differences between human and animal data are discussed.

Appetite and food preference in depression: effects of imipramine treatment

A nutritional survey, the Pittsburgh Appetite Test (PAT), was developed to study potential changes in appetite and food preference reported by patients during a depressive episode and during antidepressant treatment. We examined a group of 50 depressed outpatients who were drug-free for 2 weeks prior to treatment with imipramine and psychotherapy for 4 months. A significant increase in the desire for "sweets" (carbohydrate--fat-rich foods) was observed during a depressive episode, compared to periods when patients recalled feeling well (retrospective data). During imipramine treatment, no further changes were observed in preference for either "sweets" or carbohydrates when compared to the medication-free period. Alterations in patient self-reports of appetite and body weight change were noted during imipramine treatment.

Salivation and depression: a role for appetitive factors

A decrease in salivary flow rate (SFR) is associated with depressive illness although the mechanisms underlying this association are unknown. Appetitive factors are known to influence SFR, but are not adequately considered in the studies of salivation and depression. Diminished SFR in depressive illness may be more closely related to the appetite disturbances commonly associated with depressive illness than to mood disorder or depressive illness per se. The implications for considering SFR as a physiological correlate of depressive illness are discussed in light of this possibility.

Chronic imipramine treatment and weight gain

A study of weight change in subjects treated with imipramine was performed on recurrent depressive outpatients. The patients (n = 52) were treated with imipramine (200-250 mg/day) and psychotherapy for 16 weeks. Each individual was weighed upon entry to the study (drug-free) and then weekly thereafter for 16 weeks. Of the 44 women (85%) and 8 men (15%) in the study, 60% of the total group had a weight gain or loss less than 5 pounds (mean = 1.1 pounds) over this time. A weight gain of 6-10 pounds was observed in 19% of subjects, while 9% of the group gained 11-15 pounds. Only 6% (3 subjects) gained more than 15 pounds. Three subjects (6%) lost 6-10 pounds. No correlations were observed between a change in weight and the subject's age, sex, prior weight, or response to medication.

Qualitative analysis of feeding behaviour through dietary selection of nutrients

Studies of brain mechanisms controlling food intake and feeding behaviour have often neglected interactions between total food (energy) intake and qualitative aspects of the dietary intake. Generally, experimental animals are presented with a single diet of fixed nutritional composition. Thus, if as a result of a given treatment, an animal has an increased or decreased appetite for a specific nutrient, then this could manifest itself as an increase or decrease in intake from the sole diet offered. As selection of food is a characteristic behaviour of all animals, and their ability to monitor intake of specific nutrients is well known, then, giving experimental animals a choice of dietary constituents could result in a wider understanding of central mechanisms governing food intake. Exploiting the ability of rats to select dietary protein and carbohydrate has suggested that brain 5-hydroxytryptamine (5-HT) is involved in the regulation of protein/carbohydrate intake. Evidence from human studies suggests that appetite disturbances which occur in obese and mood-disturbed individuals may be linked to an impaired functioning of the brain 5-HT system.

Chronic amitriptyline potentiates feeding induced by intrahypothalamic norepinephrine injections

Feeding responses to microinjections of 37 nmol norepinephrine (NE) into the medial hypothalamus of rats were assessed before and after chronic amitriptyline treatment (AMI, 10 mg/kg twice daily for 21 days). AMI-treated rats showed a 55% increase in NE-induced feeding over their pre-treatment baseline. Control rats which received daily vehicle injections showed only a non-significant 3% increase on retests. These results are consistent with recent evidence suggesting that chronic AMI may enhance the responsivity of postsynaptic alpha adrenoceptors. The data also suggest that altered hypothalamic NE mechanisms may contribute to the enhanced appetite changes reported by patients undergoing long-term AMI treatment.