[Polypharmacy in psychiatric patients as an alternative to limited mental health resources]

INTRODUCTION

Polypharmacy with psychoactive drugs is an increasingly common and debatable contemporary practice in clinical psychiatry more probably based on experience than evidence. The objective of this study was to evaluate the prevalence and estimators of polypharmacy in psychiatric patients living in an area with very limited mental health resources.

METHOD

All patients (n = 352) with mental disorders receiving psychotropic medication living in La Gomera were studied through an audit of case records and a second phase confirmation strategy through personal interviews.

RESULTS

The mean number of psychoactive drugs prescribed was 2.22 +/- 0.70 (range: 1-6). The rate of polypharmacy was 67 %, with 34.1 % of patients receiving two drugs, 20.5 % receiving three drugs and 12.5 % of the patients receiving four or more psychotropic drugs at the same time. Multiple regression analysis shows that none of the variables considered (age, sex, marital status, educational level, work activity and diagnosis) had predictive value in regards to the number of psychotropic drug used. Benzodiazepines were the most prevalent drugs in single drug therapy, while antidepressants and antipsychotics were the most used in combination with other treatment. A questionably very high degree of same-class polypharmacy was observed, while multiclass, adjunctive and augmentation polypharmacy seems to be more appropriate.

CONCLUSION

The psychiatric clinical practice needs to develop indicators for an appropriate polypharmacy of mental disorders. More research is still needed to identify patients at risk of polypharmacy in order to develop interventions that minimize the risks associated to this treatment alternative.

Prescribed daily doses and 'risk factors' associated with the use of benzodiazepines in primary care

OBJECTIVE

To assess the extent, characteristics and determinants of benzodiazepine prescription in outpatient Primary Health Care.

METHODS

A clinical audit of a stratified random sample of Primary Health Care Centres in the seven islands and 1.6 million inhabitants region of 'Canarias' in Spain was carried out. From those centres, a random sample of 1045 clinical records was reviewed and information on diagnosis, prescription and prescribed dosages was collected in a structured questionnaire. A multivariate logistic regression analysis was performed in order to determine the 'risk factors' for the use of benzodiazepines.

RESULTS

Benzodiazepine prescription was recorded in 23.4% of all clinical records; 87.7% of these were for benzodiazepines classified as anxiolytics (N05B) and 12.3% for hypnotics (N05C2). Benzodiazepine prescription was more common for women, elderly, widowed, divorced, low educational background, housewives and retired people. Using multivariate logistic regression, the probability of benzodiazepine prescription was found to be closely related to age, gender and employment status, but not with educational level. Prescribed Daily Doses were lower than Defined Daily Doses (DDD) in 77.1% of all anxiolytic prescriptions, but were in agreement with DDD in 90% of hypnotic prescriptions. The duration of treatment recorded in the clinical records was 25+/-21 months, with a range of 1 and 144 months. General Practitioners were responsible for 67% of all benzodiazepine prescription. Anxiolytics were prescribed as a single daily dose in 57% of the cases, and only 'at supper' in 48.6%.

CONCLUSION

In the general population attending Primary Health Care Centres of the Canary Islands Health System the prescription of benzodiazepines is higher for women and the elderly, and the most common use is chronic, with a duration of over 2 years in most cases. Anxiolytics are prescribed in doses which are much lower than those used as DDD and were used only 'at night' in almost half of the cases. This could represent an overlapping of the indications with hypnotics, and explain part of the huge difference in the use of anxiolytics in Spain compared with other figures in Europe. This fact must also be taken into account when making inferences of benzodiazepine use from sales statistics, which are very imprecise measures of drug use.

Evaluation of a triple-lumen central venous heparin-coated catheter versus a catheter coated with chlorhexidine and silver sulfadiazine in critically ill patients

OBJECTIVE

To compare the incidence of catheter colonization and catheter-related bloodstream infections between heparin-coated catheters and those coated with a synergistic combination of chlorhexidine and silver sulfadiazine.

DESIGN

Randomized, controlled clinical trial.

SETTING

A 20-bed medical-surgical intensive care unit.

PATIENTS

A total of 180 patients requiring the insertion of a trilumen central venous catheter. INTERVENTIONS. Patients were randomized to receive either a trilumen heparin or chlorhexidine and silver sulfadiazine-coated catheter.

MEASUREMENTS

Catheter colonization was defined by a semiquantitative catheter tip culture yielding 15 or more colony-forming units or quantitative culture of 1,000 or more colony-forming units/ml. Catheter-related bloodstream infection as the isolation of the same microorganism from a peripheral blood culture and catheter tip.

RESULTS

A total of 260 catheters were cultured. Out of 132 heparin-coated catheters, 29 were colonized and out of 128 chlorhexidine and silver sulfadiazine-coated catheters, 13 were colonized ( p=0.03), relative risk RR=2.16 (1.18-3.97). This represents an incidence of 23.5 and 11.5 episodes of catheter colonization per 1,000 catheter-days, respectively ( p=0.0059), RR=2.04 (1.05-3.84). Microorganisms isolated in catheter colonization from heparin-coated catheters were gram-positive cocci 23, gram-negative bacilli 7, and Candida spp 4. In chlorhexidine and silver sulfadiazine-coated catheters were gram-positive cocci 6 and gram-negative bacilli 11 ( p=0.009). The incidence of catheter-related bloodstream infections per 1,000 catheter-days was 3.24 in heparin-coated catheters and 2.6 in chlorhexidine and silver sulfadiazine-coated catheters ( p=0.79), RR=1.22 (0.27-5.43).

CONCLUSIONS

In critically ill patients the use of trilumen central venous catheters coated with chlorhexidine and silver sulfadiazine reduced the risk of catheter colonization due to prevention of gram-positive cocci and Candida spp.

Thermoluminescence response of calcic bentonite subjected to conditions of high nuclear waste underground storage

Bentonite is regarded as a backfilling material for underground storage facilities of highly radioactive nuclear waste built on granite formations. In these facilities, bentonite will be subjected to a gradient of temperature and dose rate, achieving a very high integrated dose and, therefore, changes in its structure and physical properties may take place. Two experiments to discriminate between the thermal and the irradiation effect were performed. In the first (named BIC 2A), samples were subjected to temperature while in the second (named BIC-2B) the combined effect of temperature and irradiation was studied. The experimental conditions were: a thermal gradient between 130 degrees C and 90 degrees C, a maximum dose rate of 3.5 kGy.h(-1) and a gradient of the integrated dose between 1.75 MGy and 10 MGy. Both experiments lasted a total of 124 days. An irradiation source of 60Co with an activity close to 300,000 Ci, and bentonite samples of 200 mm in length and 50 mm in diameter were used. After the experiment, the samples were ground and two fractions were obtained: a fine fraction (<2 microm) enriched in montmorillonite clay mineral and a coarse fraction (>80 microm). The results are described of thermoluminescence analyses on the two fractions obtained which showed that the coarse fraction can be 100 times more sensitive to radiation than the fine fraction. On the other hand, the heated and irradiated samples showed a thermoluminescence response around 50 times greater than the samples that were only heated. In addition to this, the temperature and dose rate conditions are relevant parameters in the generation and stabilisation of radiation induced defects. Finally, the response of samples heated and irradiated for two months was quite similar to that obtained on samples heated and irradiated for four months, indicating a saturation phenomenon.

The Severity of Dependence Scale (SDS) as screening test for benzodiazepine dependence: SDS validation study

AIMS

To assess the validity of the Severity of Dependence Scale (SDS) as a screening test to detect benzodiazepine dependence in regular benzodiazepine users.

METHOD

One hundred regular benzodiazepine users, recruited from neurotic benzodiazepine users attending the Mental Health Outpatient Services of the Canary Islands Health Service, were administered the SDS and responses were compared with the Composite International Diagnostic Interview (CIDI) diagnosis of benzodiazepine dependence. Receiver Operating Characteristic (ROC) analysis was used to determine which cut-off score on SDS allowed the best trade-off between sensitivity and specificity.

RESULTS

SDS was shown to have high diagnostic utility, and a score higher than six on the scale appears to be an appropriate threshold for problematic benzodiazepine use. The SDS had a specificity of 94.2% and a sensitivity of 97.9%, and the area under the curve was of 0.991.

CONCLUSION

The SDS was found to be a valid brief self-report questionnaire for the assessment of benzodiazepine dependence in patients using benzodiazepines.

[In vitro activity of piperacillin-tazobactam against Klebsiella pneumoniae clinical isolates, producers or not of extended spectrum beta-lactamases]

The aim of this study was to determine the in vitro activity of piperacillin-tazobactam against 81 clinical isolates of Klebsiella pneumoniae. The clinical specimens were processed according to standard microbiological procedures and 81 K. pneumoniae isolates were identified using MicroScan Panels following the manufacturer's recommendations. A double disk diffusion method was applied to detect extended spectrum betalactamases (ESBL) (43 isolates were positive and 38 were negative). Minimum inhibitory concentrations (MIC) were determined by an agar dilution technique using Mueller-Hinton. The following antibiotics were studied: piperacillin with 4 mg/l of tazobactam, amoxicillin-clavulanic acid in a 2:1 proportion, cefotaxime, ceftriaxone, cefepime, imipenem and meropenem. The MIC(90) were 16/4 mg/l for piperacillin-tazobactam, 16/8 for amoxicillin-clavulanic acid, 16 for ceftriaxone, 16 for cefotaxime, 4 for cefepime, 0.25 for imipenem and 0.032 for meropenem in ESBL-positive strains. In ESBL-negative strains the MIC90 were as follows: 4/4 mg/l for piperacillin-tazobactam, 8/4 for amoxicillin-clavulanic acid, 0.064 for ceftriaxone, 0.125 for cefotaxime, 0.125 for cefepime, 0.125 for imipenem and 0.016 for meropenem. All betalactams showed excellent in vitro activity against ESBL non-producer K. pneumoniae. Moreover, piperacillin-tazobactam and both carbapenems showed good in vitro activity against EBSL-producer K. pneumoniae.

In vitro activity of clinafloxacin against fluoroquinolone resistant Spanish clinical isolates

The in vitro activity of clinafloxacin against 162 ciprofloxacin-resistant clinical isolates was determined. Isolates were selected when their MIC to ciprofloxacin was 2 mg/l (intermediate) or > 2 mg/l (resistant). The following strains were tested: 61 Escherichia coli, 12 Klebsiella pneumoniae, 7 Proteus mirabilis, 21 Serratia marcescens, 4 Enterobacter cloacae, 21 Pseudomonas aeruginosa, 21 Staphylococcus. aureus (resistant to methicillin) and 15 Enterococcus spp. Clinafloxacin, ciprofloxacin, ofloxacin and norfloxacin activities were evaluated by agar dilution using Müeller-Hinton agar according to NCCLS recommendations. Of the 162 isolates, 16 (9.8%) were intermediate and 146 (90.1%) resistant to ciprofloxacin. 95 of the 162 strains (58.6%) were susceptible, 27 (16.7%) intermediately susceptible, and 40 strains (24.7%) were resistant to clinafloxacin. The percentage susceptible to clinafloxacin was 65.6% for E. coli, 75% for K. pneumoniae, 71.4% for P. mirabilis, 28.6% for S. marcescens, 75% for E. cloacae, 33.3% for P. aeruginosa, 90.5% for S. aureus and 40% for Enterococcus spp. Clinafloxacin was active against 58.6% of the ciprofloxacin-resistant clinical isolates tested. It was particularly active against S. aureus strains resistant to both ciprofloxacin and methicillin.

[Corynebacterium jeikeium septicemia]

An adult male with non-Hodgkin lymphoma, who had been admitted to the hospital for more than one month and had received previous antibiotic therapy, developed Corynebacterium jeikeium septicemia. The organism was isolated in four blood cultures and it was multirresistant, being only sensitive to vancomycin, ciprofloxacin, norfloxacin and rifampin. The patient improved clinically and was bacteriologically cured with intravenous vancomycin therapy.