Stratified medicine for the use of antidiabetic medication in treatment of type II diabetes and cancer: where do we go from here?

At present, the global diabetes epidemic is affecting 347 million individuals, 90% of whom are diagnosed with type II diabetes mellitus (T2DM). T2DM is commonly treated with more than one type of therapy, including oral antidiabetic drugs (OADs) and agents used in the treatment of diabetic complications. Several pharmacological classes of OADs are currently available for the treatment of T2DM, of which insulin secretagogues (i.e. sulphonylureas and meglitinides), insulin sensitizers [thiazolidinediones (TZDs)] and biguanides are the most commonly prescribed. Although many of these OADs have been used for more than half a century in the treatment of T2DM, the pharmacogenomic characteristics of these compounds have only recently been investigated, primarily in retrospective studies. Recent advances in pharmacogenomics have led to the identification of polymorphisms that affect the expression and function of drug-metabolizing enzymes and drug transporters, as well as drug targets and receptors. These polymorphisms have been shown to affect the therapeutic response to and side effects associated with OADs. The aim of this review was to provide an up-to-date summary of some of the pharmacogenomic data obtained from studies of T2DM treatment, with a focus on polymorphisms in genes affecting pharmacokinetics, pharmacodynamics and treatment outcome of the most commonly prescribed OADs. In addition, the implications of pharmacogenomics in the use of the OAD metformin in cancer will be briefly discussed. Finally, we will focus on recent advances in novel 'omics' technologies and discuss how these might aid in the personalized management of T2DM.

[Herbal medicines: when to use or not to use?]. / Pflanzliche Arzneimittel: Wann, wann nicht?

Herbal medicines are popular. It is frequently assumed that they are effective and safe. Sound knowledge of existing, or lacking, data on the efficacy and safety is required for advice and for the decision whether or not to use a particular herbal drug. Cochrane reviews are available for some herbal remedies. Most of them indicate either insufficient knowledge or weak or lacking efficacy. Numerous studies on interactions, some of which are clinically significant, for St. John's wort with conventional drugs are available. Overall, although knowledge about herbal drugs has grown in recent years, it is generally still unsatisfactory. The active recommendation to use an herbal drug is usually not advisable. However, a patient's request for a licensed herbal drug may be acceptable if there is no conventional concomitant comedication that is known or expected to interact, no contra-indication, and no other (conventional) treatment with better, or better known, benefit-risk ratio.

Analgesic drug use associated with statin prescription--a cross-sectional study in primary care settings.

BACKGROUND: To investigate whether features of muscular complaints (MC) differ between receivers of a statin prescription and non-receivers. To analyze the relationship between analgesics prescription, statin prescription and/or musculoskeletal disorders. METHODS: Cross-sectional study. Consecutive patients in offices of family practitioners were interviewed using a standardized questionnaire. Target variables: Rates of features of MC in patients with or without a statin prescription and rates of analgesic drug prescription in patients with or without statin prescription and/or musculoskeletal disorders. Odds ratios (adjusted for age, sex, and socio-economic status) were calculated using logistic regression analysis. RESULTS: 1135 patients in 26 general practitioners' offices were asked to participate, and 1031 patients agreed. Features of MC did not differ between the two groups of patients. Analgesic prescription was found to be associated with statin prescription in patients without musculoskeletal disorders (OR 2.2, CI 1.1-4.7 without statin, OR 2.5, CI 0.9-6.9 with statin) and particularly in those with musculoskeletal disorders (OR 5.2, CI 2.9-9.3 without statin, OR 9.3, CI 4.5-19.1 with statin). CONCLUSIONS: Analgesic prescriptions are probably positively associated with statin prescription. Assuming that analgesics attenuate MC, an even stronger association between MC and statin use seems likely. The results generate the hypothesis that statin use contributes to analgesic use in primary care patients.

Drug treatment for chronic systolic heart failure.

Drug treatment of chronic systolic heart failure usually includes angiotensin-converting enzyme inhibitor, or an angiotensin II receptor blocker, and a beta blocker, as prognostic benefit of these agents has been demonstrated in a large body of clinical trials. Depending on the stage of the disease and concomitant factors, an aldosterone antagonist and/or a digitalis glycoside may provide additional benefit. Most patients also receive a diuretic for symptomatic relief. Conversely, some drugs may precipitate or aggravate chronic systolic heart failure.

[Unwanted side effects of antibacterials--a diagnostic challenge]. / Unerwünschte Arzneimittelwirkungen von Antibiotika--eine differenzialdiagnostische Herausforderung.

We present three cases of rare side effects which appeared to be attributable to antibacterial drug treatment. A 57-year-old female patient was admitted to hospital due to increasing dyspnea. Computed tomography revealed interstitial lung fibrosis which was attributed to the toxic effects of nitrofurantoin (50 mg/d) that the patient used for approximately one year for recurrent urinary tract infection. She died two weeks after hospital admission due to acute respiratory failure. A 20-year-old male patient presented with most intense headache and psychomotor deceleration. Pseudotumor cerebri, which was suspected to be the underlying cause, is described as a rare side effect of minocyclin which the patient has taken for acne pustulosa (100 mg single dose). After dechallenge of minocyclin, neurological symptoms quickly subsided. A 82-year-old female patient used moxifloxacin (400 mg/d) for febrile bronchopulmonary infection for one week. During this therapy, confusion and severe dementia presented and remained for more than two months after discontinuation. The demential syndrome appears to be possibly related to the fluoroquinolone use. In summary, adverse drug effects not pertaining to the primary physician's field are especially difficult to identify. Most importantly, rare side effects must be borne in mind by the prescribing physician.

Propafenone for the prevention of atrial tachyarrhythmias after cardiac surgery: a randomized, double-blind placebo-controlled trial.

We studied the efficacy of propafenone in preventing atrial tachyarrhythmias after cardiac surgery, and the possible relationships between CYP2D6 polymorphism and the efficacy, pharmacokinetics, and tolerability of propafenone. One hundred and sixty patients were randomized (double blind) to receive propafenone (n= 78) or placebo (n= 82) for 1 week after cardiac surgery. The patients who were assigned to the propafenone group received 1 mg/kg infused in 1 h, followed by a continuous infusion at a rate of 4 mg/kg/24 h until the following morning, and subsequently 450 mg/day orally until the sixth postoperative day. Thirty-seven patients completed the trial in the propafenone group and 45 in the placebo group. The frequency of occurrence of atrial tachyarrhythmia was lower in the propafenone group than in the placebo group (29.7% vs. 53.3%, P< 0.05; relative risk, 0.56). Plasma propafenone concentrations were markedly influenced by CYP2D6 genotype-derived phenotype.

Multiple drug prescribing by general practitioners in a German region: Implications for drug interactions and patient safety.

OBJECTIVE: An increased number of drugs used by patients enhances the risk of potentially hazardous drug interactions. So far, no representative data are available about how common this problem is in German general practices. METHODS: We performed a retrospective analysis using a prescription database for a German region. The 50 general practitioners (out of 1,457) who wrote the most prescriptions during January to March 2003 were included. Data on 4,153 patients who were prescribed at least 10 drugs were analyzed for 92 predefined Drug Combinations Prone to Interact (DCPI) to a clinically relevant extent and possible contraindications. RESULTS: From 92 DCPIs, 71 occurred in the analyzed population between 1 and 275 times. The total number of DCPI cases was 1,295, which included 10% (n = 129) of contraindicated combinations. Among 4,153 analyzed patients, 822 patients (19.8%) were affected by at least 1 DCPI. In 268 patients (6.5%), multiple DCPIs occurred. The most frequently found drug pairs were digitalis/diuretics, digitalis/calcium channel blockers, and theophylline/quinolones. Among contraindicated combinations, tricyclic antidepressants, St. John's wort and antiarrhythmic drugs were most frequently involved. In about 1/3 of patients treated for chronic heart failure, pharmacotherapy appeared not to be guideline-adherent. CONCLUSION: Drug interactions, especially in polypharmacotherapy, represent a potential hazard which must be taken into account by the prescribing physician. Our study is the first to use a prescription database for the evaluation of drug prescriptions within a German region.

Valproic acid-associated sialadenosis of the parotid and submandibular glands: diagnostic and therapeutic aspects.

Sialadenosis has been defined as a non-inflammatory, parenchymatous salivary gland disease causing recurrent, bilateral swelling of the salivary glands. As an adverse drug reaction of valproic acid, sialadenosis is very rare. To our knowledge, it has been reported only once in the world literature to date. We present herein the case of a patient with valproic acid-associated sialadenosis of both the parotid and submandibular glands. This appears to be the first published case of a patient who received surgical treatment. On light and electron microscopy of all the affected salivary glands, granular sialadenosis with predominantly moderate electron-dense secretory cytoplasmatic granules was observed. No relevant degenerative alterations were seen. There was no histological evidence of peripheral neuropathy of the nerve supply, leading to disordered activity of acinar cells by loss of neurosecretory granules. Lateral parotidectomy, performed under neuromonitoring control for safety reasons, is the treatment of choice for chronic recurrent parotitis that does not respond to conservative therapy, particularly if the cosmetic deformity is unacceptable to the patient. If the submandibular glands are involved, partial removal is recommended.

Effect of acute hyperhomocysteinemia on methylation potential of erythrocytes and on DNA methylation of lymphocytes in healthy male volunteers.

Homocysteine is a precursor of S-adenosylmethionine (AdoMet) and a metabolite of S-adenosylhomocysteine (AdoHcy). The ratio of AdoMet to AdoHcy, defined as the methylation potential (MP), indicates the flow of methyl groups within the cells. Chronic elevations of total homocysteine (tHcy) in plasma correlate with increased AdoHcy concentrations, decreased MP, and impaired DNA methylation. However, the influence of acute hyperhomocysteinemia on MP is unknown. We induced acute hyperhomocysteinemia in 14 healthy volunteers by oral administration of l-homocysteine (65.1 micromol/kg body wt) in an open, randomized, placebo-controlled two-period crossover study. The kinetics of tHcy in blood and urine, MP in blood, and global DNA methylation in lymphocytes were studied systematically during 48 h. Plasma tHcy concentrations reached a peak at 34 +/- 11 min after an oral load with l-homocysteine and decreased with a half-life of 257 +/- 41 min (means +/- SD). Only 2.3% of the homocysteine dose were recovered in urine. AdoHcy concentrations and MP in whole blood and erythrocytes were not affected by the oral homocysteine load. Furthermore, global DNA methylation in lymphocytes did not change under these conditions. We found no difference between the genotypes of 5,10-methylenetetrahydrofolate reductase in response to the homocysteine load. However, AdoMet content in erythrocytes was significantly higher in the C677T carriers (CT; n = 7) compared with the CC genotype (n = 7). Although chronic elevation of tHcy has been shown to affect MP and DNA methylation, acute elevation of plasma tHcy above 20 micromol/l for 8 h is not sufficient to change MP and to induce DNA hypomethylation in lymphocytes.

[The Guideline Clearing Project COPD. Recommendations for a National Guideline]. / Das Leitlinien-Clearingverfahren COPD. Empfehlungen für eine nationale Leitlinie.

In order to promote the care of patients with COPD in Germany a national guideline clearing project was initiated jointly by autonomous corporate bodies of the German health care system. Following a systematic search of literature data bases between 1992 and 2002, 20 guidelines were identified that met the inclusion criteria and were evaluated with the German Checklist for Methodological Guideline Appraisal. Following this, a multidisciplinary expert group appointed by the German Guideline Clearinghouse (Leitlinien-Clearingstelle im Arztlichen Zentrum fur Qualitat in der Medizin, AZQ) reviewed the suitability of these guidelines for the use in the German health care system. Referring to methodological aspects, criteria were best met by the guideline of the Veteran's Health Administration/Department of Defense (US), followed by the one of the Deutsche Atemwegsliga and the Deutsche Gesellschaft fur Pneumologie. Aiming at the production respectivly a revision of a German national guideline for COPD the expert group agreed on recommendations organized in 19 chapters. Among others these strengthened the role of a precise definition of COPD based primarily on the pathogenesis, of a subtle description of all diagnostic and therapeutic tools and of a detailed description of quality assurance and quality management. The feasability of recommendations were demonstrated by examples chosen from the evaluated guidelines. Additionally the presented findings may be used as steering tools in the German Health care system.

[The German guideline clearing-project on bronchial asthma - part 2: recommendations and key topics for a national guideline on bronchial asthma]. / Das Leitlinien-Clearingverfahren Asthma bronchiale - 2. Empfehlungen zu Eckpunkten für eine nationale Leitlinie Asthma bronchiale.

BACKGROUND: In order to promote the quality of asthma management in Germany, a national asthma guidelines clearing project was initiated in 2000 by the German Guidelines Clearinghouse (Sponsors: German Medical Association (GMA), National Association of the Statutory Health Insurance Physicians (NASHIP), German Hospital Federation, Federal Association of the Statutory Sickness Funds. This Part shows the key topics which should be dealt with in a German guideline on bronchial asthma. SUMMARY POINTS: For quality promotion of bronchial asthma management in Germany, the development of a national evidence-based guideline, using the internationally accepted quality criteria for clinical practice guidelines, was recommended by an expert group of the German Guideline Clearinghouse. The experts identified and peer-reviewed 16 out of 54 guidelines, which might be useful as benchmarks and examples for a German asthma guideline. From the peer review results, the expert group identified 18 key topics for a national asthma guideline.

[Phytotherapeutic medicines. A possible source of drug interactions]. / Pflanzliche Arzneimittel. Eine mögliche Quelle von Wechselwirkungen.

Herbal drugs are popular. Coming from nature, many people are still reluctant to link them with the risk of adverse effects. Many of these products do not require a prescription. Thus, their use and any potential risks may easily escape the physician's attention. Interactions, causing either adverse effects or treatment failures, with synthetic drugs have attracted increasing interest and recent case reports (e.g. about patients suffering from transplant rejection upon using of St John's wort with subsequently insufficient cyclosporine levels) have triggered some systematic research. As of yet, however, a substantial part of knowledge is based on case reports only. In this situation, the assessment of potential risks arising from herb drug interactions is difficult. More research is needed. This review is a brief account of interactions involving garlic, ginkgo, ginseng, echinacea, and St John's wort.

Do alterations of endogenous angiotensin II levels regulate erythropoietin production in humans?

AIMS: Recent evidence suggests a potential role of angiotensin II in the physiological regulation of erythropoietin (Epo) production. While the administration of exogenous angiotensin II (AII) has been used so far to study its effects, the role of endogenous AII has remained unclear. METHODS: To alter endogenous AII in humans experimentally we used furosemide bolus injection as a short-term (study 1) and dietary salt as a long-term modulator (study 2). In an open crossover design, 12 healthy male volunteers received furosemide (F) 0.5 mg kg(-1) intravenously or placebo (P) in random order (study 1). With the same design, 12 volunteers received high-salt (HS), normal-salt (NS) and low-salt (LS) diet (study 2). Plasma renin activity (PRA) was analysed along with AII. Inulin and paraaminohippurate (PAH) clearances were used to indicate glomerular filtration rate (GFR) and renal plasma flow (RPF), respectively. RESULTS: While F stimulated AII and PRA and decreased GFR and RPF significantly, no concomitant alteration of Epo was observed [AUCEpo: placebo 5709 +/- 243 (% of baseline x h), furosemide: 5833 +/- 255 (% of baseline x h); 95% confidence interval (CI) -608.4, 856.0; P = 0.73]. F decreased GFR (from 103.6 +/- 4.0 to 90.6 +/- 4.8 ml min(-1) 1(-1) 73 m-2; 95% CI 1.1, 24.9; P < 0.05), but not RPF (study 1). Correspondingly, LS stimulated and HS decreased AII and PRA significantly. HS increased GFR and RPF. Again, Epo concentrations were not affected (AUCEpo: normal sodium 44 +/- 6.7 mIU x day ml(-1), low sodium 39 +/- 2.4 mIU x day ml(-1), high sodium 48.5 +/- 6.1 mIU x day ml(-1); normal salt/low salt 95% CI -11.9, 21.9, P = 0.54; normal salt/high salt 95% CI -14.4, 23.3, P = 0.63; study 2). CONCLUSIONS: We conclude that, at least in the physiological setting in healthy volunteers, increased concentrations of endogenous AII may not be a major factor of Epo regulation.

[The German guideline clearing-project on bronchial asthma-part 1: Methodology and results of formal appraisal]. / Das Leitlinien-Clearingverfahren Asthma bronchiale--1. Methodik und Ergebnisse der formalen Bewertung.

BACKGROUND: In order to promote quality of asthma management in Germany, a national asthma guidelines clearing project was initiated in 2000 by the German Guidelines Clearinghouse (Sponsors: German Medical Association (GMA), National Association of the Statutory Health Insurance Physicians (NASHIP), German Hospital Federation, Federal Association of the Statutory Sickness Funds. Part 1 of this article shows the methodology and the results of the appraisal, part 2 (to be published) shows the key topics which should be dealt with in a german guideline on bronchial asthma. OBJECTIVES: To identify and compare evidence-based, high-quality German- and English language asthma guidelines as benchmarks for ongoing guideline development and implementation programmes. To disseminate information about asthma guidelines developed in accordance with current methodological know-how. To identify and consent key topics for a national evidence-based guideline for Germany. METHODS: Search procedure, formal appraisal: Systematic search using literature databases (XMED, incl. Medline and Embase) and English-/German-language guideline databases (via www. leitlinien.de), published between January 1990 and March 2000. Abstract screening of the search results according to the inclusion criteria (n = 54 of a total of 502 hits). Methodological guideline evaluation of 16 guidelines using the German checklist for methodological guideline appraisal. Appraisal of guidelines' contents: Peer review of guidelines with the following inclusion criteria: Bronchial Asthma-general, German and English language, based in references published later than 1994, new guideline or actual update. Peer review was performed by a multidisciplinary focus group of EBM experts (clinical and ambulatory settings). No expert was involved in guideline production during the review period. RESULTS: Methodological appraisal: 16 out of guidelines were in accordance with the formal minimal standard with a wide range within the following domains: "description of the development process", "declaration of authors' independence", "explicit link between recommendations and the supporting evidence", "management options", "tools for implementation". The focus group recommended for future national asthma guidelines to rely on the following procedures: (1) to formulate the recommendations using standardized, clearly described consensus methods basing on evidence retrieved and selected in a systematic way (2) to prove links between recommendations and supporting evidence (3) to develop guideline versions for health care professionals as well as for consumer/patients (4) to develop guideline-based education tools (5) to ensure periodical updates of the asthma guideline (6) to consider the methodological recommendations and to give reasons for deviations from the methodological recommendations. APPRAISAL OF GUIDELINES CONTENT: None of the guidelines identified comprised information about all of the following key topics considered to be relevant for a German national guideline by the focus group: (1) intended guideline users/goals, (2) definition (3) cause of disease, (4) form of disease, (5) severity, (6) diagnosis, (7) therapeutic goals, (8) prevention, (9) pharmacotherapy, (10) non-pharmacotherapy, (11) therapy control and compliance, (12) emergency treatment, (13) rehabilitation, (14) comorbidity, (15) special aspects, (16) coordination of care, (17) quality assurance/quality management, (18) implementation. SUMMARY POINTS: For quality promotion of bronchial asthma management in Germany, the development of a national evidence-based guideline, using the internationally accepted quality criteria for clinical practice guidelines, was recommended by an expert group of the German Guideline Clearinghouse. The experts identified and peer-reviewed 16 out of 54 guidelines, which might be useful as benchmarks and examples for a German asthma guideline. From the peer review results, the expert group identified 18 key topics for a national asthma guideline.

[Medicinal drugs and automobile driving ability]. / Arzneimittel und Fahrtüchtigkeit.

When prescribing drugs, the physician is responsible to warn his patient about potential impairment of driving capability. To do this, he needs to be aware of the duration and profile of actions, notably sedative and other effects affecting vigilance, cognitive and psychomotor functions. It is advisable to keep written records about such information. Impairment of driving capability may be more pronounced when ethanol is used during the action of drugs affecting central nervous function. The majority of published studies, particularly from epidemiological work with drivers, indicate an increased risk of accidents associated with the therapeutic use of benzodiazepines or cyclic antidepressants. Epidemiological data for other drugs available so far do not allow definite conclusions. Among antihistamines for drivers, loratadine or fexofenadine are probably preferable to ceritizine or older antihistamines. Patients with diabetes who drive should be informed about the risks and self-management of hypoglycaemia.

["Off-label" prescribing of drugs in the ambulatory care of children and adolescents]. / "Off-label" Verschreibung von Arzneimitteln in der ambulanten Versorgung von Kindern und Jugendlichen1.

BACKGROUND AND OBJECTIVE: Hospitalised children receive up to 90 % of their drug prescriptions without ("unlicensed use") or outside ("off-label use") the terms of their product license. As no data are available for pediatric outpatients in Germany, we determined "off-label" use in a representative cohort of children and adolescents. PATIENTS AND METHODS: We analyzed 1.74 million prescriptions, written from January 1 st through March 31 st, 1999, to 455 661 children and adolescents aged 0 to 16 years by 6886 specialists in pediatric, general or internal medicine. All prescriptions were covered by the public health insurance, Allgemeine Ortskrankenkasse, (AOK) Baden-Wuerttemberg. License status of 1 592 006 identifiable prescriptions comprising more than 10 000 differently branded drugs was determined in 5 age groups and in different groups of the Anatomical Therapeutical Chemical Classification (ATC). As reference documents for licensing status we used the "Fachinformation" (summary of product characteristics), the "Rote" and "Gelbe" Liste, respectively. RESULTS: 13.2 %, i. e. 210 528 of the 1.59 million prescriptions, were "off-label". 75 % of these "off-label" prescriptions were due to a lack of information on pediatric use in the summary of product characteristics. The highest "off-label" fractions were found in drugs topically used in eyes and ears (78.6 %), dermatological (57.9 %), cardiovascular drugs (55.2 %), drugs für musculoskeletal (45.2 %) and urogenital disorders (48.5 %) and antidepressants (36.6 %). CONCLUSION: "Off-label" prescribing in outpatient children is less frequent than in pediatric inpatients. Considering the high absolute number of prescriptions however, 13.2 % cannot be neglected. Doctors prescribing drugs for children and adolescents should be aware of their actual licensing status because of its medical and legal consequences.