Background: CDP-choline is used in the treatment of disorders of a cerebrovascular nature. The many years of its presence in the clinical field have caused an evolution in dosage, method of administration, and selection criteria of patients to which the treatments was given. Modalities of the clinical studies, including length of observation, severity of disturbance, and methodology of evaluation of the results were also heterogeneous. In spite of uncertainties about its efficacy due to these complexities, CDP-choline is a frequently prescribed drug for cognitive impairment in several European countries, especially when the clinical picture is predominantly one of cerebrovascular disease, hence the need for this review.
Objectives: The objective is to assess the efficacy of CDP-choline (cytidinediphosphocholine) in the treatment of cognitive, emotional, and behavioural deficits associated with chronic cerebral disorders in the elderly.
Search strategy: The trials were identified from a last updated search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 20 January 2004 using the terms CDP-choline, CDP, citicolone, cytidine diphosphate choline or diphosphocholine. This register contains records from all major health care databases and many ongoing trials databases and is updated regularly.
Selection criteria: All relevant unconfounded, double-blind, placebo-controlled, randomized trials of CDP-choline for cognitive impairment due to chronic cerebral disorders are considered for inclusion in the review.
Data collection and analysis: Two reviewers independently reviewed the included studies, extracted the data, and pooled it when appropriate and possible. The pooled odd ratios (95% CI) or the average differences (95% CI) were estimated. No intention-to-treat data were available from the studies included.
Main results: Seven of the included studies observed the subjects for a period between 20 to 30 days, one study was of 6 weeks duration, 4 studies used cycles extending over 2 and 3 months and one study observed continuous administration over 3 months. The studies were heterogeneous in dose, inclusion criteria for subjects, and outcome measures. Results are reported for the domains of attention, memory testing, behavioural rating scales, global clinical impression and tolerability. There is no significant evidence of a beneficial effect of CDP-choline on attention. There are significant beneficial effects of CDP-choline on memory function and behaviour. The drug is well tolerated.
Reviewers' conclusions: There is some evidence that CDP Choline has a positive effect on memory and behaviour in at least the short/medium term. The evidence of benefit from global impression is stronger, but is still limited by the duration of the studies. Further research with CDP-choline should focus on longer term studies in subjects who have been diagnosed with currently accepted standardised criteria, especially vascular dementia.