Ambulatory-treated Clostridium difficile infection: a comparison of community-acquired vs. nosocomial infection.

The purpose of this study was to identify the clinical outcomes of ambulatory-treated Clostridium difficile infection (CDI) and risk factors associated with community-associated CDI (CA-CDI). Adult patients diagnosed with CDI in the institutional or ambulatory-care setting between 1 April 2005 and 30 April 2011, with no other CDI diagnosis in the previous 180 days, and who purchased an ambulatory, anti-CDI agent within 7 days of CDI diagnosis were included. A total of 1201 patients were included with 914 (76%) and 287 (24%) identified with CA-CDI and nosocomial CDI (N-CDI), respectively. Patients with N-CDI were more likely to have had a recurrent CDI (P = 0·043) and died from any cause (P < 0·001). Patients with CA-CDI were younger, healthier, and had fewer traditional risk factors compared to patients with N-CDI. To prevent CA-CDI, clinicians should be aware that patients at risk for CA-CDI are unique from those at risk for N-CDI.

An evaluation of the potential drug interaction between warfarin and levothyroxine.

BACKGROUND: Drug interaction references report that initiation of levothyroxine potentiates the effects of warfarin, and recommend more frequent International Normalized Ratio (INR) monitoring, but the mechanism is not well understood. OBJECTIVE: To assess the impact of levothyroxine initiation on INR response. PATIENTS/METHODS: A retrospective, self-controlled study was performed on patients aged ≥ 18 years receiving chronic warfarin therapy who were started on levothyroxine between 1 January 2006 and 30 June 2013, and who were followed for 90 days prior to and after levothyroxine initiation. The included patients had at least one elevated thyroid-stimulating hormone laboratory value in the pre-period, continuous warfarin therapy for 100 days prior to levothyroxine initiation, no purchases of medications known to interact with warfarin, no procedures requiring warfarin interruption, and no bleeding or thromboembolic event during the study period. The primary outcome was a comparison of the warfarin dose/INR ratio recorded before the initiation of levothyroxine with the ratio recorded during the post-period after two consecutive INRs with no warfarin dose change. RESULTS: One hundred and two patients were included in the primary outcome. The mean warfarin dose/INR ratios in the pre-period and post-period were equivalent (P = 0.825). Although the mean warfarin dose was numerically lower in the post-period than in the pre-period, this difference did not reach statistical significance (P = 0.068). CONCLUSION: No difference in the mean warfarin dose/INR ratio before and after initiation of levothyroxine was detected. The results suggest that there is not a clinically significant interaction between warfarin and levothyroxine, and so additional monitoring may not be necessary.

Twelve-month outcomes and predictors of very stable INR control in prevalent warfarin users.

BACKGROUND: For patients on warfarin therapy an international normalized ratio (INR) recall interval not exceeding 4 weeks has traditionally been recommended. For patients whose INR values are nearly always therapeutic, less frequent INR monitoring may be feasible. OBJECTIVE: To identify patients with stable INRs (INR values exclusively within the INR range) and comparator patients (at least one INR outside the INR range), compare occurrences of thromboembolism, bleeding and death between groups, and identify independent predictors of stable INR control. METHODS: The study was a retrospective, longitudinal cohort study using data extracted from electronic databases. Patient characteristics and risk factors were entered into multivariate logistic regression models to identify variables that independently predict stable INR status. RESULTS: There were 533 stable and 2555 comparator patients. Bleeding and thromboembolic complications were significantly lower in stable vs. comparator patients (2.1% vs. 4.1% and 0.2% vs. 1.3%, respectively; P < 0.05). Independent predictors of stable INR control were age >70 years, male gender and the absence of heart failure. Stable patients were significantly less likely to have target INR > or =3.0 or chronic diseases. CONCLUSION: A group of patients with exclusively therapeutic INR values over 12 months is identifiable. In general, these patients are older, have a target INR <3.0, and do not have heart failure and/or other chronic diseases. Our findings suggest that many patients whose INR values remain within the therapeutic range over time could be safely treated with INR recall intervals >4 weeks.

Incidence and predictors of bleeding or thrombosis after polypectomy in patients receiving and not receiving anticoagulation therapy.

BACKGROUND AND AIMS: To assess the effect of warfarin anticoagulation therapy (AC) on the incidence of colon bleeding after elective colonoscopy with polypectomy and to identify independent predictors of post-polypectomy colon bleeding. METHODS: This was a retrospective cohort analysis. Patients interrupting warfarin AC therapy for polypectomy (AC group) were matched on age (+/- 3 years) with up to two patients who underwent polypectomy but were not receiving AC (non-AC group). Data were extracted from electronic medical, pharmacy and laboratory claims and records and manual medical chart review. Incidence rates of colon bleeding requiring hospitalization, other gastrointestinal bleeding, thrombosis and death in the 30 days post-polypectomy were compared between groups. Multivariate regression techniques were used to identify independent predictors of post-polypectomy colon bleeding. RESULTS: A total of 425 AC group patients were matched to 800 non-AC group patients. Post-polypectomy colon bleeding occurred more often in AC group patients (2.6% vs. 0.2%, P = 0.005). There were no differences in the rates of other outcomes (P > 0.05). Independent predictors of colon bleeding included AC group status [adjusted odds ratio (AOR) = 11.6; 95% confidence interval (CI) = 2.3-57.3], number of polyps removed (AOR = 1.2; 95% CI = 1.1-1.4) and male gender (AOR = 9.2, 95% CI = 1.1-74.9). CONCLUSIONS: The incidence of post-polypectomy colon bleeding was higher in patients receiving AC even although warfarin was interrupted for the procedure. Independent predictors of colon bleeding were identified as: receiving AC, removal of multiple polyps and male gender. Our findings suggest that additional methods to reduce the likelihood of post-polypectomy colon bleeding in AC patients should be investigated.

Patterns of use of sildenafil among commercially insured adults in the United States: 1998-2002.

Sildenafil is increasingly being marketed to younger healthcare consumers. The purpose of this study was to profile sildenafil use in commercially insured, adult beneficiaries. Annual ambulatory prescription claims data from 1998 to 2002, for a nationwide, random sample of over 5 million life-years of commercially insured adults (aged > or =18 y), were examined retrospectively. The overall prevalence of sildenafil use increased from 0.8% (1998) to 1.4% (2002), an 84% increase. While the growth in use slowed in older males, use became more pronounced in younger males and females and decreased in older females. The fastest growing segment of users was found to be males aged 18-45 y. The proportion of users who had two or more claims for a medication that is suspected of inducing erectile dysfunction (ED) and/or a marker for a suspected ED-inducing disease decreased over the study period. Our findings suggest that use may increase among younger male and female patients and those without an underlying etiologic reason for use.

The use of 2 health-related quality-of-life measures in a sample of persons infected with human immunodeficiency virus.

The purpose of this analysis was to examine the ability of the MOS-HIV (Medical Outcomes Study-Human Immunodeficiency Virus) Health Survey and the EuroQol Group's EQ-5D questionnaire to discriminate between subjects in predefined disease-severity groups on the basis of clinical-indicator status (i.e., CD4 cell counts, HIV type 1 [HIV-1] RNA copies). This study used medical records of and instruments completed by 242 HIV-infected patients. The ability of the health-related quality-of-life instruments to discriminate between subjects stratified by disease severity was assessed by means of receiver-operating characteristic (ROC) curve analysis. The EQ-5D (P<.05) and MOS-HIV physical health summary (PHS) scores (P<.01) were able to discriminate between groups of subjects stratified by disease severity on the basis of either CD4 cell counts or HIV-1 RNA copies. These findings provide further evidence of the validity of the use of EQ-5D and the MOS-HIV questionnaire and suggest that they may be practical tools for the monitoring of health status from the HIV-infected patient's perspective.

The discriminative ability of the 12-item short form health survey (SF-12) in a sample of persons infected with HIV.

BACKGROUND: Self-reported health-related quality of life (HRQOL) assesses constructs that transcend laboratory-based clinical parameters. Corroboration of the hypothesized relationships between the 2 types of health indicators (ie, clinical and HRQOL) could provide evidence of the validity of an HRQOL measurement tool. OBJECTIVE: The purpose of this study was to evaluate the ability of scores on the mental component summary (MCS-12) and physical component summary (PCS-12) of the 12-Item Short Form Health Survey (SF-12) to discriminate between HIV-infected persons in predefined disease-severity groups based on surrogate markers. METHODS: This cross-sectional study involved the collection of clinical data (ie, CD4 cell count, viral load [HIV-1 RNA copies/mL]) from patients' medical records and HRQOL data from the SF-12 at 2 HIV specialty clinics. The ability of SF-12 summary scores to discriminate between patients stratified by disease severity (ie, CD4 cell count <200 vs > or = 200/mm3; HIV-1 RNA >55,000 vs < or = 55,000 copies/mL) was assessed by receiver operating characteristic curve analysis. RESULTS: Data were collected from 478 patients. The scores from the PCS-12 were able to discriminate between groups of patients stratified by disease severity based on CD4 cell count (P < 0.001) and HIV-1 RNA copies/mL (P < 0.01). MCS-12 scores did not discriminate between disease-severity groups. CONCLUSIONS: Although the SF-12 is a brief generic measure of HRQOL, these findings provide further evidence of the validity of the SF-12 and suggest that it may be a practical way to monitor health status from the perspective of the HIV-infected patient.

Ribozymes targeted to stearoyl-ACP delta9 desaturase mRNA produce heritable increases of stearic acid in transgenic maize leaves.

Ribozymes are RNAs that can be designed to catalyze the specific cleavage or ligation of target RNAs. We have explored the possibility of using ribozymes in maize to downregulate the expression of the stearoyl-acyl carrier protein (Delta9) desaturase gene. Based on site accessibility and catalytic activity, several ribozyme constructs were designed and transformed into regenerable maize lines. One of these constructs, a multimer hammerhead ribozyme linked to a selectable marker gene, was shown to increase leaf stearate in two of 13 maize lines. There were concomitant decreases in Delta9 desaturase mRNA and protein. The plants with the altered stearate phenotype were shown to express ribozyme RNA. The ribozyme-mediated trait was heritable, as evidenced by stearate increases in the leaves of the R1 plants derived from a high-stearate line. The increase in stearate correlated with the presence of the ribozyme gene. A catalytically inactive version of this ribozyme did not produce any significant effect in transgenic maize. This is evidence that ribozymes can be used to modulate the expression of endogenous genes in maize.

Post-transcriptional regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase by 24(S),25-oxidolanosterol.

We have examined the mechanism of regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase by 24(S),25-oxidolanosterol, a C30-sterol naturally occurring in mammalian tissues. In the absence of enzymatic demethylation to the C27-sterol, 24(S),25-epoxycholesterol, oxidolanosterol is shown to be a post-transcriptional regulator of reductase synthesis in both primary rat hepatocytes and Chinese hamster ovary cells. Under these conditions, oxidolanosterol also increases the rate of degradation of reductase protein in these cells. When demethylation is not inhibited, oxidolanosterol treatment produces transcriptional regulation of sterol-sensitive genes in Chinese hamster ovary cells. In contrast to previous findings with the oxygenated C27-sterol, 25-hydroxycholesterol, oxidolanosterol can act as a post-transcriptional regulator in cells starved for mevalonate. These findings are consistent with the hypothesis that oxidolanosterol down-regulates sterol synthesis in a fashion mechanistically distinct from that of C27-sterols.