A systematic review and meta-analysis of diabetes disease management programs

Context. Despite the rapid growth of disease management programs, there are still questions about their efficacy and effectiveness for improving patient outcomes and their ability to reduce costs associated with chronic disease. ^ Objective. To determine the effectiveness of disease management programs on improving the results of HbA1c tests, lipid profiles and systolic blood pressure (SBP) readings among diabetics. These three quantitative measures are widely accepted methods of determining the quality of a patient's diabetes management and the potential for future complications. ^ Data Sources. MEDLINE and CINAHL were searched from 1950 to June 2008 using MeSH terms designed to capture all relevant studies. Scopus pearling and hand searching were also done. Only English language articles were selected. ^ Study Selection. Titles and abstracts for the 2347 articles were screened against predetermined inclusion and exclusion criteria, yielding 217 articles for full screening. After full article screening, 29 studies were selected for inclusion in the review. ^ Data Extraction. From the selected studies, data extraction included sample size, mean change over baseline, and standard deviation for each control and experimental arm. ^ Results. The pooled results show a mean HbA1c reduction of 0.64%, 95% CI (-0.83 to -0.44), mean SBP reduction of 7.39 mmHg (95% CI to -11.58 to -3.2), mean total cholesterol reduction of 5.74 mg/dL (95% CI, -10.01 to -1.43), and mean LDL cholesterol reduction of 3.74 mg/dL (95% CI, -8.34 to 0.87). Results for HbA1c, SBP and total cholesterol were statistically significant, while the results for LDL cholesterol were not. ^ Conclusions. The findings suggest that disease management programs utilizing five hallmarks of care can be effective at improving intermediate outcomes among diabetics. However, given the significant heterogeneity present, there may be fundamental differences with respect to study-specific interventions and populations that render them inappropriate for meta-analysis. ^

Systematic review of genetic risk score in coronary heart disease and other diseases

In order to better take advantage of the abundant results from large-scale genomic association studies, investigators are turning to a genetic risk score (GRS) method in order to combine the information from common modest-effect risk alleles into an efficient risk assessment statistic. The statistical properties of these GRSs are poorly understood. As a first step toward a better understanding of GRSs, a systematic analysis of recent investigations using a GRS was undertaken. GRS studies were searched in the areas of coronary heart disease (CHD), cancer, and other common diseases using bibliographic databases and by hand-searching reference lists and journals. Twenty-one independent case-control studies, cohort studies, and simulation studies (12 in CHD, 9 in other diseases) were identified. The underlying statistical assumptions of the GRS using the experience of the Framingham risk score were investigated. Improvements in the construction of a GRS guided by the concept of composite indicators are discussed. The GRS will be a promising risk assessment tool to improve prediction and diagnosis of common diseases.^

Effect of smoking on the association between periodontitis and incidence of coronary heart disease: The Atherosclerosis Risk in Communities Study

Multiple studies have shown an association between periodontitis and coronary heart disease due to the chronic inflammatory nature of periodontitis. Also, studies have indicated similar risk factors and patho-physiologic mechanisms for periodontitis and CHD. Among these factors, smoking has been the most discussed common risk factor and some studies suggested the periodontitis - CHD association to be largely a result of confounding due to smoking or inadequate adjustment for it. We conducted a secondary data analysis of the Dental ARIC Study, an ancillary study to the ARIC Study, to evaluate the effect of smoking on the periodontitis - CHD association using three periodontitis classifications namely, BGI, AAP-CDC, and Dental-ARIC classification (Beck et al 2001). We also compared these results with edentulous ARIC participants. Using Cox proportional hazard models, we found that the individuals with the most severe form of periodontitis in each of the three classifications (BGI: HR = 1.56, 95%CI: 1.15 – 2.13; AAP-CDC: HR = 1.42, 95%CI: 1.13 – 1.79; and Dental-ARIC: HR = 1.49, 95%CI: 1.22 – 1.83) were at a significantly higher risk of incident CHD in the unadjusted models; whereas only BGI-P3 showed statistically significant increased risk in the smoking adjusted models (HR = 1.43, 95%CI: 1.04 – 1.96). However none of the categories in any of the classifications showed significant association when a list of traditional CHD risk factors was introduced into the models. On the other hand, edentulous participants showed significant results when compared to the dentate ARIC participants in the crude (HR = 1.56, 95%CI: 1.34 – 1.82); smoking adjusted (HR = 1.39, 95%CI: 1.18 – 1.64) age, race and sex adjusted (HR = 1.52, 95%CI: 1.30 – 1.77); and ARIC traditional risk factors (except smoking) adjusted (HR = 1.27, 95%CI: 1.02 – 1.57) models. Also, the risk remained significantly higher even when smoking was introduced in the age, sex and race adjusted model (HR = 1.38, 95%CI: 1.17 – 1.63). Smoking did not reduce the hazard ratio by more than 8% when it was included in any of the Cox models. ^ This is the first study to include the three most recent case definitions of periodontitis simultaneously while looking at its association with incident coronary heart disease. We found smoking to be partially confounding the periodontitis and coronary heart disease association and edentulism to be significantly associated with incident CHD even after adjusting for smoking and the ARIC traditional risk factors. The difference in the three periodontitis classifications was not found to be statistical significant when they were tested for equality of the area under their ROC curves but this should not be confused with their clinical significance.^

Bisphosphonates for metastatic bone disease in lung cancer

Bisphosphonates have proven effectiveness in preventing skeletal-related events (SREs) in advanced breast cancer, prostate cancer and multiple myeloma. The purpose of this study was to assess efficacy of bisphosphonates in preventing SREs, in controlling pain, and in increasing life expectancy in lung cancer patients with bone metastases.^ We performed an electronic search in MEDLINE, EMBASE, Web of Science, and Cochrane library databases up to April 4, 2010. Hand searching and searching in clinicaltrials.gov were also performed. Two independent reviewers selected all clinical trials that included lung cancer patients with bone metastases treated with bisphosphonates. We excluded articles that involved cancers other than lung, patients without bone metastasis and treatment other than bisphosphonates. Outcome questions answered were efficacy measured as overall pain control, overall improvement in survival and reduction in skeletal-related events or SREs (fracture, cord compression, radiation or surgery to the bone, hypercalcemia of malignancy). The quality of each study was evaluated using the Cochrane Back Review group questionnaire to assess risk of bias (0-worst to 11-best). Data extraction and quality assessments were independently performed by two assessors. Meta-analyses were performed where more than one study with similar outcomes were found.^ We identified eight trials that met our inclusion criteria. Three studies evaluated zoledronic acid, three pamidronate, three clodronate and two ibandronate. Two were placebocontrol trials while two had multi-group comparisons (radiotherapy, radionucleotides, and chemotherapy) and two had different bisphosphonate as active controls. Quality scores ranged from 1-4 out of 11 suggesting high risk of bias. Studies failed to report adequate explanation of randomization procedures, concealment of randomization and blinding. Metaanalysis showed that patients treated with zoledronic acid alone had lower rates of developing SREs compared to placebo at 21 months (RR=0.80, 95% CI=0.66-0.97, p=0.02). Meta-analyses also showed increased pain control when a bisphosphonate was added to the existing treatment modality like chemotherapy or radiation (RR=1.17, 95% CI=1.03-1.34, p=0.02). However, pain control was not statistically significantly different among various bisphosphonates when other treatment modalities were not present. Despite improvement in SRE and pain control, bisphosphonates failed to show improvement in overall survival (Difference in means=109.1 days, 95% CI= -51.52 – 269.71, p=0.183).^ Adding biphosphonates to standard care improved pain control and reduced SREs. Biphosphonates did not improve overall survival. Further larger studies with higher quality are required to stengthen the evidence.^ Keywords/MeSH terms Bisphosphonates/diphosphonates: generic, chemical and trade names.^