Partially hydrolyzed guar gum in the treatment of irritable bowel syndrome with constipation: effects of gender, age, and body mass index.

BACKGROUND/AIMS: Partially hydrolyzed guar gum (PHGG) relieves symptoms in constipation-predominant irritable bowel syndrome (IBS) and may have prebiotic properties. However, the correlation between the effectiveness of PHGG and patient characteristics has not been examined. We aimed to investigate the effect of PHGG in symptom relief on constipation-predominant IBS according to gender, age, and body mass index (BMI). PATIENTS AND METHODS: Sixty-eight patients with IBS entered a 2-week run-in period, followed by a 4-week study period with PHGG. Patients completed a daily questionnaire to assess the presence of abdominal pain/discomfort, swelling, and the sensation of incomplete evacuation. The number of evacuations/day, the daily need for laxatives/enemas and stool consistency-form were also evaluated. All patients also underwent a colonic transit time (CTT) evaluation. RESULTS: PHGG administration was associated with a significant improvement in symptom scores, use of laxatives/enemas, stool form/consistency and CTT. At the end of the study period and compared with baseline, the number of evacuations improved in women, patients aged ≥ 45 years and those with BMI ≥ 25 (P < 0.05 for all comparisons); abdominal bloating improved in males (P < 0.05), patients < 45 years (P < 0.01) and those with BMI < 25 (P < 0.05). A decrease in the number of perceived incomplete evacuations/day was reported in patients with a BMI ≥ 25 (P < 0.05). Reductions in laxative/enema use were recorded in females (P < 0.05), patients < 45 years (P < 0.01), and patients with BMI < 25 (P < 0.05). CONCLUSIONS: Gender, age, and BMI seem to influence the effect of PHGG supplementation in constipated IBS patients. Further studies are needed to clarify the interaction of such parameters with a fiber-enriched diet.

Proton pump inhibitors prescribing following the introduction of generic drugs.

BACKGROUND: In many countries, the introduction of generic proton pump inhibitors (PPIs) onto the pharmaceutical market increased the phenomenon of therapeutic substitution in acid-related disorders (ARDs). AIM: To investigate the treatment of ARDs in an Italian primary care setting from 2005 to 2008 by verifying: (i) dynamics of PPI prescribing; (ii) predictors of PPI switching; and (iii) healthcare resource consumption costs. METHODS: This was a retrospective cohort study of 102 general practitioners (GPs) who managed an average of 150000 inhabitants in Naples. Multilevel logistic regression was used to assess the potential predictors of both PPI switching and termination. Primary care costs were expressed as the cost of ARD management per PPI user year. RESULTS: The percentage of PPI users with ARD increased from 5·5% (2005) to 7·0% (2008) (P<0·0001), especially for dyspepsia (from 9·5% to 13·7%; P<0·0001) and chronic treatments (from 23·4% to 29·4%; P<0·0001). PPI switching rose from 13·0% to 16·7% during the period observed (P<0·0001). Calendar years, long-term treatments and gastroesophageal reflux disease were positive predictors of PPI switching. Primary care costs relating to PPI switchers increased by 61·14€ compared with nonswitchers (P<0·0001). CONCLUSIONS: The introduction of generic PPIs onto the Italian market was associated with an increasing amount of PPI prescribing related to chronic treatments, unlicensed indications (e.g. dyspespsia) and therapeutic substitutions. Growing overall costs linked to the phenomenon of PPI switching was also found. Our data support the need to assess the effects of the introduction of generic drugs on both clinical outcomes and the cost management of ARDs.