Helicobacter pylori eradication and l-dopa absorption in patients with PD and motor fluctuations. Helicobacter pylori eradication in dyspeptic primary care patients: a randomized controlled trial of a pharmacy intervention.
To investigate if Helicobacter pylori (HP) eradication could make an effective and long-lasting improvement in the pharmacokinetic and clinical response to l-dopa in patients with Parkinson disease (PD) and motor fluctuations.
                In a group of 34 HP-infected, motor-fluctuating patients with PD, the short-term (1-week) and long-term (3-month) beneficial effect of HP eradication (n = 17) was investigated in a double-blind fashion in comparison with a generic antioxidant treatment (n = 17), by means of pharmacokinetic, clinical, and gastrointestinal assessments. Results were compared with placebo treatment.
                Differently from the antioxidant-treated patients, the HP-eradicated patients showed a significant increase of l-dopa absorption, which was coupled with a significant improvement of clinical disability and with a prolonged "on-time" duration, whereas gastritis/duodenitis scores significantly decreased in line with a better l-dopa pharmacokinetics.
                These data demonstrate a reversible Helicobacter pylori (HP)-induced interference with l-dopa clinical response related to the impaired drug absorption, probably due to active gastroduodenitis. Therefore, the authors suggest that HP eradication may improve the clinical status of infected patients with Parkinson disease and motor fluctuations by modifying l-dopa pharmacokinetics. To determine the effectiveness of structured adherence counseling by pharmacists on the eradication of Helicobacter pylori when using a standard drug treatment regimen.
                Randomized controlled clinical trial.
                Nonprofit group-practice health maintenance organization (HMO).
                HMO primary care providers referred 1,393 adult dyspeptic patients for carbon 14 urea breath testing (UBT).
                Those whose tests were positive for H pylori (23.3%) were provided a standard antibiotic regimen and randomly assigned to receive either usual-care counseling from a pharmacist or a longer adherence counseling session and a follow-up phone call from the pharmacist during drug treatment. All subjects were given the same 7-day course of omeprazole, bismuth subsalicylate, metronidazole, and tetracycline hydrochloride (OBMT). Dyspepsia symptoms were recorded at baseline and following therapy.
                The main outcome was eradication of H pylori as measured by UBT at 3-month follow-up. Secondary outcomes were patient satisfaction and dyspepsia symptoms at 3-month follow-up.
                Of the 333 participants randomly assigned to treatment, 90.7% completed the 3-month follow-up UBT and questionnaires. Overall eradication rate with the OBMT regimen was 80.5% with no significant difference in eradication rates between the 2 groups (P=0.98). Conclusions In this study, additional counseling by pharmacists did not affect self-reported adherence to the treatment regimen, eradication rates, or dyspepsia symptoms but did increase patient satisfaction.
There is currently a lack of evidence on the effects of screening and treating H pylori in patients with Parkinson's disease. There is limited evidence to suggest that H Pylori eradication improves the absorption of levodopa and improves motor symptoms. Results from an ongoing trial will inform the evidence base and will be incorporated in an update of this review. There is a need for well-conducted randomised controlled trials with standard outcome measures for motor symptoms and incorporating the costs of screening and treatment.