Unmet need in the hyperlipidaemia population with high risk of cardiovascular disease: a targeted literature review of observational studies

Background

The aim of this study was to examine recommended target levels of low-density lipoprotein cholesterol (LDL-C) for hyperlipidaemia patients at high risk (i.e., with two or more risk factors or coronary heart disease or its risk equivalents) for cardiovascular disease (CVD); to determine LDL-C targets recommended by guidelines, and to examine the proportions of patients who do not achieve targeted LDL-C levels in real-world studies.

Methods

Electronic databases were searched: Medline, Medline In-Process, Embase, BIOSIS, and the Cochrane Library (1 January 2005 to 31 December 2013). Guideline searches were limited to publications in the last 5 years. There were no geographical or language restrictions.

Results

Seventeen guidelines and 42 observational studies that reported on high-risk hyperlipidaemia patients were identified. The National Cholesterol Education Program–Adult Treatment Panel III’s LDL-C target levels were the most common guidelines used for patients with very high hyperlipidaemia. However, between 68 and 96 % of patients in the studies did not achieve an LDL-C goal <70 mg/dL, except in one study conducted in China (16.9 %). In high-risk patients, 61.8 to 93.8 % did not achieve a target of <100 mg/dL. Regarding common comorbidities, patients with concomitant CVD or diabetes were least likely to reach their target LDL-C goals.

Conclusion

In patients with high risk for CVD, the majority of patients do not attain recommended LDL-C goals, highlighting worldwide suboptimal hyperlipidaemia management and missed opportunities for reduction of the patients CVD risk. Lipid-modifying management strategies need to be intensified.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-016-0241-3) contains supplementary material, which is available to authorized users.

Interventions for preventing tobacco smoking in public places

BACKGROUND

Environmental tobacco smoke is a health hazard. Reducing exposure to tobacco smoke in public places is a widespread public health goal. There is, however, considerable variation in the extent to which this goal has been achieved in different settings and societies. There is therefore a need to identify effective strategies for reducing tobacco consumption in public places.

OBJECTIVES

To evaluate the effectiveness of interventions to reduce tobacco consumption in public places.

SEARCH STRATEGY

We searched the Tobacco Addiction Review Group trials register, Medline, EMBASE, HEALTHSTAR, PAIS, and CDP File (National Centre for Chronic Disease Prevention and Health Promotion, CDC) "Smoking and Health database". We handsearched a key journal and abstracts from international conferences on tobacco. We checked the bibliographies of identified studies and reviews for additional references.

SELECTION CRITERIA

We considered randomized and controlled trials, controlled before and after studies and interrupted time series, and uncontrolled before and after studies. We considered strategies aimed at populations, including education campaigns, written material, non-smoking and warning signs, and comprehensive strategies. We also considered strategies aimed at individual smokers.

DATA COLLECTION AND ANALYSIS

Information relating to the characteristics and content of all kinds of interventions, participants, outcomes and methods of the study was abstracted by one reviewer and checked by two others. Studies were combined using qualitative narrative synthesis.

MAIN RESULTS

Eleven of 22 studies reporting information about interventions to reduce smoking in public places met all the inclusion criteria. All included studies were uncontrolled before and after studies. The most effective strategies used comprehensive, multicomponent approaches to implement policies banning smoking within institutions. Less comprehensive strategies, such as posted warnings and educational material had a moderate effect. Five studies showed that prompting individual smokers had an immediate effect, but such strategies are unlikely to be acceptable as a public health intervention.

REVIEWER'S CONCLUSIONS

Carefully planned and resourced, multicomponent strategies effectively reduced smoking within public places. Less comprehensive strategies were less effective. All the studies used relatively weak experimental designs. Most studies were done in the USA, and there is a need to identify ways in which these strategies can be adopted and used in countries with different attitudes to tobacco use. Future studies should also consider the use of more rigorous experimental designs.

Controversy of oral contraceptives and risk of rheumatoid arthritis: meta-analysis of conflicting studies and review of conflicting meta-analyses with special emphasis on analysis of heterogeneity

The authors analyze the heterogeneity present in the combined results of past observational studies that investigated the association between oral contraceptive use and rheumatoid arthritis. The authors also evaluate discrepancies among meta-analyses that focus on the same relation. Of the 15 initially reviewed studies, 10 were selected for this meta-analysis, which also includes a qualitative summary of study characteristics and a critical appraisal of study quality. The authors used the direct method to combine the study results when there was no evidence of heterogeneity and the DerSimonian-Laird method when heterogeneity was present. Using a meta-regression to assess the sources of heterogeneity, the authors weighted summary estimates by sample size and undertook a sensitivity analysis. There was a strong indication of heterogeneity when combining all studies (x2 = 29.34, p = 0.00060) with the source of controls explaining most of the heterogeneity. The most important factor in explaining the differences among the overall summary estimates given by the meta-analyses is that different effect estimates had been selected for the same studies. There is no conclusive evidence of a protective effect of oral contraceptives on the risk of developing rheumatoid arthritis. Consensus is needed on how meta-analyses of observational studies should be conducted.