Changing prescription of low-dose aspirin into calcium carbasalate (brand name: Ascal) to prevent peptic ulcerations is not useful. Peptic ulcers are evenly distributed among users of calcium carbasalate and aspirin, for secondary prevention of myocardial infarction.
These numbers are presented in a scientific publication by researchers of the Radboud University Nijmegen Medical Centre and the Erasmus Medical Centre Rotterdam (The Netherlands), online first in Clinical Gastroenterology and Hepatology, the official clinical journal of the American Gastroenterology Association (AGA).
More than 1.1 million patients are prescribed low-dose aspirin for platelet aggregation inhibition in The Netherlands (GIP database, CVZ 2006). However, a significant number of patients on aspirin experience side effects, like bloating, nausea or even peptic ulcers. These effects can be contributed to both local and systemic pathways: 1) poor disintegration of aspirin may cause drug concentration to be higher in certain parts of the stomach leading to a direct irritating effect; 2) aspirin decreases the production of prostaglandins, that are required for gastric mucosal wall integrity. Consequently, aspirin can change the gastric environment into more sensitive for development of peptic ulcerations.
Calcium carbasalate is a salt formulation of aspirin, and therefore more soluble and less harmful to the stomach. In order to prevent local toxic effects, this seemed a useful alternative for patients that experience or have a higher risk for side effects on aspirin. However, strict comparison in a study supervised by Martijn van Oijen MSc of the department of Gastroenterology and Hepatology of the Radboud University Nijmegen Medical Centre, indicate that cardiovascular patients using calcium carbasalate develop peptic ulcers to the same amount as on aspirin.
For this purpose the Dutch IPCI (Integrated Primary Care Information) database was studied: a general practice research database containing data from approximately 500,000 electronic patient records of a group of about 150 general practitioners. All patients using low-dose aspirin (11,891) or low-dose calcium carbasalate (7,928) were selected. In these patients 115 peptic ulcers were found. After adjustment for the duration of medication use and risk factors, the risk for peptic ulcer was similar in the group using calcium carbasalate compared with aspirin.
This implicates that peptic ulcers seem to be related to systemic effects on gastric mucosal wall integrity rather than to local irritating effects in patients using low-dose aspirin.
The researchers are aware of the limitations of the observational study. Because of its protective image, physicians may prescribe calcium carbasalate preferably to patients with known gastrointestinal complaints, which may modify the results of the study. To overcome this issue, the usage of acid suppressive drugs in the study population was analyzed and found not different between users of calcium carbasalate and aspirin.