Cochrane Db Syst Rev
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Retinitis pigmentosa (RP) comprises a group of hereditary eye diseases characterized by progressive degeneration of retinal photoreceptors. It results in severe visual loss that may lead to legal blindness. Symptoms may become manifest during childhood or adulthood, and include poor night vision (nyctalopia) and constriction of peripheral vision (visual field loss). This field loss is progressive and usually does not reduce central vision until late in the disease course.The worldwide prevalence of RP is one in 4000, with 100,000 patients affected in the USA. At this time, there is no proven therapy for RP. ⋯ Based on the results of three RCTs, there is no clear evidence for benefit of treatment with vitamin A and/or DHA for people with RP, in terms of the mean change in visual field and ERG amplitudes at one year and the mean change in visual acuity at five years follow-up. In future RCTs, since some of the studies in this review included unplanned subgroup analysis that suggested differential effects based on previous vitamin A exposure, investigators should consider examining this issue. Future trials should take into account the changes observed in ERG amplitudes and other outcome measures from trials included in this review, in addition to previous cohort studies, when calculating sample sizes to assure adequate power to detect clinically and statistically meaningful difference between treatment arms.
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Cochrane Db Syst Rev · Dec 2013
ReviewAnticholinergic medication for non-clozapine neuroleptic-induced hypersalivation in people with schizophrenia.
Treatment of schizophrenia depends heavily on neuroleptic drugs. Hypersalivation is a common side effect when people with schizophrenia are treated with neuroleptic drugs. Hypersalivation can be an embarrassing and stigmatising problem, can affect quality of life and can result in discontinuation of neuroleptic treatment. It can also be difficult to treat. ⋯ We have been unable to locate any studies addressing the question raised in this review. Accordingly, this empty review points out an important clinical problem that needs to be investigated via well-designed and well-conducted randomised trials. Clinicians and patients are likely to continue with their current dependence on clinical judgement and personal experience. Policy makers have no trial-based evidence upon which to base guidelines for the treatment of hypersalivation induced by neuroleptics other than clozapine. They are likely to continue to rely on opinion and habit when making recommendations. Funders of studies may wish to make this important subgroup of people a priority in future research.
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Cochrane Db Syst Rev · Dec 2013
Review Meta AnalysisCombination versus sequential single agent chemotherapy for metastatic breast cancer.
Combination chemotherapy can cause greater tumour cell kill if the drug dose is not compromised, while sequential single agent chemotherapy may allow for greater dose intensity and treatment time, potentially meaning greater benefit from each single agent. In addition, sequentially using single agents might cause less toxicity and impairment of quality of life, but it is not known whether this might compromise survival time. ⋯ Sequential single agent chemotherapy has a positive effect on progression-free survival, whereas combination chemotherapy has a higher response rate and a higher risk of febrile neutropenia in metastatic breast cancer. There is no difference in overall survival time between these treatment strategies, both overall and in the subgroups analysed. In particular, there was no difference in survival according to the schema of chemotherapy (giving chemotherapy on disease progression or after a set number of cycles) or according to the line of chemotherapy (first-line versus second- or third-line). Generally this review supports the recommendations by international guidelines to use sequential monotherapy unless there is rapid disease progression.
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Cochrane Db Syst Rev · Dec 2013
ReviewBreathing exercises for dysfunctional breathing/hyperventilation syndrome in children.
Dysfunctional breathing is described as chronic or recurrent changes in breathing pattern causing respiratory and non-respiratory symptoms. It is an umbrella term that encompasses hyperventilation syndrome and vocal cord dysfunction. Dysfunctional breathing affects 10% of the general population. Symptoms include dyspnoea, chest tightness, sighing and chest pain which arise secondary to alterations in respiratory pattern and rate. Little is known about dysfunctional breathing in children. Preliminary data suggest 5.3% or more of children with asthma have dysfunctional breathing and that, unlike in adults, it is associated with poorer asthma control. It is not known what proportion of the general paediatric population is affected. Breathing training is recommended as a first-line treatment for adults with dysfunctional breathing (with or without asthma) but no similar recommendations are available for the management of children. As such, breathing retraining is adapted from adult regimens based on the age and ability of the child. ⋯ The results of this systematic review cannot inform clinical practice as no suitable trials were identified for inclusion. Therefore, it is currently unknown whether these interventions offer any added value in this patient group or whether specific types of breathing exercise demonstrate superiority over others. Given that breathing exercises are frequently used to treat dysfunctional breathing/hyperventilation syndrome, there is an urgent need for well-designed clinical trials in this area. Future trials should conform to the CONSORT statement for standards of reporting and use validated outcome measures. Trial reports should also ensure full disclosure of data for all important clinical outcomes.