Comparison of 50-mg and 100-mg sustained-release isosorbide mononitrate in the treatment of stable angina pectoris: Effects on quality-of-life indices

In a self-controlled, 6-month study, the effects of 50 mg and 100 mg of sustained-release isosorbide mononitrate (SR ISMN), administered once daily, on anginal symptoms and quality of life (QOL) were assessed in 351 patients with stable angina pectoris, QOL was assessed by means of a battery of tests based on the Medical Outcomes Study Short-Form 36 Health Survey and the Angina Pectoris Quality of Life Questionnaire, The internal consistency and reliability of the multi-item scales were estimated using Cronbach's alpha coefficient. Based on improvements in New York Heart Association (NYHA) angina classification, patients who received 100 mg daily showed greater improvement than those who received 50 mg daily; the mean difference between treatments was consistent with a significantly greater improvement of mobility and angina indices. Adverse effects, as estimated by the side-effect index, including rebound angina, at times of rest, and by patient compliance rating, differed slightly between the two treatment regimens and were even less problematic with the higher dosage than with the lower dosage, Psychological distress index and Life satisfaction scores also were significantly higher with 100 mg than with 50 mg daily. The: results of this study suggest that SR ISMN 100 mg once daily provided a better NYHA angina classification than did SR ISMN 50 mg and did not produce further adverse effects. In addition SR ISMN 100 mg improved various QOL indices more than did SR ISMN 50 mg, particularly the mobility index and certain life satisfaction scores, which are the most important indicators of QOL in this category of patients