Effectiveness and safety of nutritional supplements in the treatment of hereditary retinal dystrophies: a systematic review.

The hereditary retinal dystrophies (HRDs) are a group of genetically determined disorders that result in loss of the visual function. There is a lack of standard pharmacological treatments or widely accepted nutritional recommendations. The objective of this review is to summarise the scientific evidence on the effectiveness and safety of nutritional supplements for the treatment of HRDs. We conducted a scientific literature search on Medline and PreMedline, EMBASE, SCI-EXPANDED, SSCI, and The Cochrane Library up to August 2014. Experimental, quasi-experimental and controlled observational studies were selected. Eight studies were ultimately included, seven on retinitis pigmentosa (RP) and one on Best disease. Vitamin A, vitamin E, docosahexaenoic acid (DHA), lutein and ß-carotene were assessed. A 15 000 IU daily dose of vitamin A was reported to have shown a small protective effect on the progression of RP, as was the use of the carotenoids lutein and ß-carotene. Different DHA doses has no effect on RP or Best disease. No supplement showed severe adverse effects in the selected studies although strong evidence of toxicity exists for high doses of vitamin A and ß-carotene in certain populations. The selected studies concluded that there may be a small beneficial effect of vitamin A, lutein and ß-carotene on the progression of RP. The limited evidence available indicates some well-designed additional studies on combined supplements strategies may achieve more robust conclusions. Moreover, the scarcity of evidence available on the treatment of HRD other than RP with nutritional supplements supports the need for further research efforts.

Efficiency of pragmatic search strategies to update clinical guidelines recommendations.

BACKGROUND: A major challenge in updating clinical guidelines is to efficiently identify new, relevant evidence. We evaluated the efficiency and feasibility of two new approaches: the development of restrictive search strategies using PubMed Clinical Queries for MEDLINE and the use of the PLUS (McMaster Premium Literature Service) database. METHODS: We evaluated a random sample of recommendations from a national guideline development program and identified the references that would potentially trigger an update (key references) using an exhaustive approach. We designed restrictive search strategies using the minimum number of Medical Subject Headings (MeSH) terms and text words required from the original exhaustive search strategies and applying broad and narrow filters. We developed PLUS search strategies, matching Medical Subject Headings (MeSH) and Systematized Nomenclature of Medicine (SNOMED) terms with guideline topics. We compared the number of key references retrieved by these approaches with those retrieved by the exhaustive approach. RESULTS: The restrictive approach retrieved 68.1 % fewer references than the exhaustive approach (12,486 versus 39,136), and identified 89.9 % (62/69) of key references and 88 % (22/25) of recommendation updates. The use of PLUS retrieved 88.5 % fewer references than the exhaustive approach (4,486 versus 39,136) and identified substantially fewer key references (18/69, 26.1 %) and fewer recommendation updates (10/25, 40 %). CONCLUSIONS: The proposed restrictive approach is a highly efficient and feasible method to identify new evidence that triggers a recommendation update. Searching only in the PLUS database proved to be a suboptimal approach and suggests the need for topic-specific tailoring.

Patient involvement in health research: a contribution to a systematic review on the effectiveness of treatments for degenerative ataxias.

This study aims to incorporate patients' perspective in the design of a systematic review of scientific literature on the effectiveness of degenerative ataxias (DA) treatments. 53 patients with DA from different regions of Spain were consulted using the Delphi method, with three rounds via e-mail. In the first round, obtained information was on treatments used and relevant self-perceived health problems related to DA. The following two rounds were used to prioritize and achieve a consensus on the answers. The participation rate was 100% for all rounds. The most relevant self-perceived health problems were limitations in activities of daily living (ADL), visual and auditory problems and diminished self-esteem. The bibliographic search for the systematic review was enriched by these patient contributions. No study offered information on treatment effectiveness for the following problems prioritized by patients: ADL, social relationships, disease acceptance and quality of life. Thus some of the self-perceived DA-related health problems identified by the patients have never been investigated and should be considered to improve future research projects which should be adapted to meet patients' needs. Effective participation of patients can extend the value of systematic reviews to ensure they respond to both clinicians' information needs and patients' expectations.

Obesity and health related quality of life in the general adult population of the Canary Islands.

PURPOSE: To explore the relationship between excess weight and health related quality of life (HRQL) in the general population by means of the EuroQol-5D questionnaire. METHODS: The relationship between excess weight and HRQL was explored by the 2004 Canary Islands Health Survey. Survey participants from 16 years of age and older were classified according to their body mass index (BMI). The relationship between excess weight and the dichotomized EuroQol-5D was examined by multiple logistic regression analysis, adjusting by socio-demographic variables, smoking status, alcohol consumption, and self-reported disease status. RESULTS: People with excess weight were older, less educated, and had more associated diseases than the population without excess weight. Excess weight and HRQL are inversely correlated. Severely obese participants showed EuroQol-5D index scores significantly lower than those of normal weight participants (0.65 vs. 0.87). The adjusted odds ratio for the lower HRQL is 3.17 for severely obese people compared to normal weight people. CONCLUSIONS: Excess weight has a negative impact on HRQL, even for people without chronic diseases. A better understanding of the relationships between excess weight, its associated comorbidities, and HRQL may have important implications for the design and assessment of prevention and treatment strategies.