Background:
Bipolar disorder is a chronic illness that is commonly associated with comorbid substance use. The development of the Clinical Global Impressions Scale Modified for Substance Use (CGI-SU) was to produce a simple, quick and easy-to-administer assessment tool. It was used in a randomized placebo-controlled trial of N-acetylcysteine (NAC) in bipolar disorder. It was hypothesized that NAC would improve the outcomes in bipolar disorder and ultimately in comorbid substance use.
Methods:
The study focused on the CGI-SU, which is a newly developed assessment tool based on the original CGI for improvements. The new scale is intended for use in routine clinical practice to monitor improvements in a patient's comorbid substance use. It was administered to participants (n = 75) in the NAC in bipolar disorder trial. The CGI-SU scale investigates changes in six items, including ethanol, caffeine, nicotine, delta-9-tetrahydrocannabinol and two additional items depending on the participants' use of substances.
Results:
About 78.7% were using ethanol, 92% caffeine, 45.3% nicotine and 7.9% delta-9-tetrahydrocan-nabinol. These participants' use of substances permitted us to monitor the improvements of their substance use over the trial period.
Conclusions:
The simplicity and brevity of the CGI-SU make it a valuable outcome measure. It enables the monitoring of the improvements or lack of improvements made by patients with bipolar disorder and comorbid substance use in observational studies and clinical practice.
