Fenfluramine challenge test predicts outcome in pharmacological treatment of patients with functional gastrointestinal disorder

Bulking agents, antispasmodic and antidepressant medication for the treatment of irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is a common health problem, often presenting in primary care as well as in internal medicine and gastroenterology outpatient clinics. Therapeutic options are dominated by drug therapies but there is uncertainty about their effectiveness.

OBJECTIVES

The primary objective of this review was to evaluate the efficacy of bulking agents, antispasmodic and antidepressant medication for the treatment of IBS.

SEARCH STRATEGY

A computer assisted search of MEDLINE, EMBASE, PsychInfo and the Cochrane Library was performed for the years 1966-2001; local and national databases were searched in 10 European countries.

SELECTION CRITERIA

Randomised trials comparing bulking agents, antispasmodic or antidepressant medications with a placebo, in IBS patients over 12 years of age. Only studies published as a full paper were included. No language criterion was applied.

DATA COLLECTION AND ANALYSIS

The search identified 687 studies, 66 of which fulfilled all eligibility criteria. After removal of cross-over studies that did not report separately on the first phase, data from 40 studies remained for analysis. Relative risk (RR), risk difference (RD) and standardized mean difference (SMD) along with 95% confidence intervals were calculated for all subgroups. The number needed to treat (NNT) was also calculated where appropriate.

MAIN RESULTS

Forty-one study reports from 40 studies, comprising 78 comparisons, were analysed. These included 11 reports on bulking agents, 6 on antidepressants, and 24 on spasmolytics.BULKING AGENTS: Three studies comprising 159 patients reported a dichotomous outcome for relief of abdominal pain. The pooled RR using a random effects model was 1.22 (95% CI 0.86 - 1.73). Three studies comprising 128 patients reported a continuous outcome for relief of abdominal pain. Using the random effects model, the SMD was 0.68 (95% CI -0.86 - 2.33). Nine studies comprising 482 patients reported a dichotomous outcome for global assessment of improvement. The pooled RR was 1.09 (95% CI 0.78 - 1.50). Five studies comprising 253 patients reported a dichotomous outcome for improvement of symptom score. The pooled RR using a random effects model was 0.93 (95% CI 0.56 - 1.54). Two studies comprising 70 patients reported a continuous outcome for improvement of symptom score; the SMD using a fixed effects model was -0.44 (95% CI -1.20 - 0.31). SPASMOLYTIC AGENTS: Eleven studies comprising 1260 patients reported a dichotomous outcome for relief of abdominal pain. The pooled RR using a random effects model was 1.34 (95% CI 1.13 - 1.59; RD=0.17, 95% CI 0.06 -0.28; NNT=6, 95% CI 4 - 15). Seven studies comprising 467 patients reported a continuous outcome for relief of abdominal pain. Using a fixed effects model the pooled SMD was -0.65 (95% CI -0.94 to -0.35). Sixteen studies comprising 1236 patients reported a dichotomous outcome for global assessment of improvement. The pooled RR using a random effects model was 1.42 (95% CI 1.17 - 1.72; RD=0.20, 95% CI 0.09 -0.30; NNT=5, 95% CI 3 - 11). One study comprising 34 patients reported a dichotomous variable for improvement of symptom score. The RR was 1.33 (95% CI 0.96 - 1.85). Three studies reported a continuous outcome for improvement of symptom score; two studies comprising 66 patients could be pooled. Using a fixed effects model, the SMD was -0.37 (95% CI -0.85 - 0.12). ANTIDEPRESSANTS: Two studies comprising 81 patients reported a dichotomous outcome for relief of abdominal pain. Using the random effects model, the pooled RR was 0.83 (95% CI 0.33 - 2.12). Two studies comprising 101 patients reported a continuous outcome for relief of abdominal pain. The SMD using a random effects model was -0.53 (95% CI -2.29 - 1.23). Four studies comprising 241 patients reported a dichotomous variable for global assessment of improvement. The pooled RR was 1.16 (95% CI 0.78 - 1.73).

AUTHORS' CONCLUSIONS

The evidence for efficacy of drug therapies for IBS is weak. Although there is evidence of benefit for antispasmodic drugs for abdominal pain and global assessment of symptoms; it is unclear whether anti-spasmodic subgroups are individually effective. There is no clear evidence of benefit for antidepressants or bulking agents. The physician should be aware that global assessment is a construct containing various dimensions. For each individual, these will have a different weighting and treatment should be aimed at the most debilitating symptom. Stool problems are by definition part of the IBS symptom complex. Bulking agents may improve constipation and can be used empirically, but should be evaluated at an early stage for individual benefit. Future research should pay attention to study methodology and the use of valid outcome measures.

Gender, aggression and serotonergic function are associated with response to sertraline for behavioral disturbances in Alzheimer's disease

BACKGROUND

Indications for serotonergic medications in the treatment of behavioral disorders associated with Alzheimer's disease (AD) remain to be established.

METHOD

Sertraline (100 mg OD) was evaluated in a double-blind, randomized, placebo-controlled cross-over study in 22 nondepressed patients with severe probable AD and significant behavioral disturbance. Each subject was given a fenfluramine challenge to evaluate central serotonergic tone.

RESULTS

Eight of 21 (38%) completers responded to sertraline. Drug responsive behaviors included aggression/agitation, irritability and aberrant motor behavior. Low aggression, female gender and large prolactin increase were associated with a better response. There was a trend for decreased aggression during sertraline versus placebo (p = 0.08).

CONCLUSION

Aggression, gender and serotonergic function were associated with sertraline response. Larger randomized controlled trials are needed to clarify the profile of responders.

Personality traits predict treatment outcome with an antidepressant in patients with functional gastrointestinal disorder

BACKGROUND

We investigated the relationship between personality traits and response to treatment with the tetracyclic antidepressant mianserin or placebo in patients with functional gastrointestinal disorder (FGD) without psychopathology.

METHODS

Forty-eight patients completed the Buss-Durkee Hostility Inventory, Neuroticism Extroversion Openness -Personality Inventory (NEO-PI), and Eysenck Personality Questionnaire (EPQ), neuroticism + lie subscales, before they were consecutively allocated to a 7-week double-blind treatment study with mianserin or placebo. Treatment response to pain and target symptoms were recorded daily with the Visual Analogue Scale and Clinical Global Improvement Scale at every visit.

RESULTS

A low level of neuroticism and little concealed aggressiveness predicted treatment outcome with the antidepressant drug mianserin in non-psychiatric patients with FGD. Inversely, moderate to high neuroticism and marked concealed aggressiveness predicted poor response to treatment. These findings were most prominent in women. Personality traits were better predictors of treatment outcome than serotonergic sensitivity assessed with the fenfluramine test.

CONCLUSION

Assessment of the personality traits negativism, irritability, aggression, and neuroticism may predict response to drug treatment of FGD even when serotonergic sensitivity is controlled for. If confirmed in future studies, the findings point towards a more differential psychopharmacologic treatment of FGD.