How patients in Denmark acquire their medicines: overview, data sources and implications for pharmacoepidemiology.

The means by which patients acquire their medications differ between countries, and a knowledge of this is essential when conducting and interpreting pharmacoepidemiological studies. The aim of this paper is to provide an overview of how patients obtain medicines in Denmark, to relate these to nationwide registries available for research and to discuss the implications for research. Health services are predominantly tax-funded in Denmark, with dentistry and some medicine bought at community pharmacies being exceptions, involving partial reimbursement of charges. The paper gives an overview of prescription medicines acquired from community pharmacies (including magistral preparations), over-the-counter medicines, vaccinations and in-hospital medicine including so-called "free medicine" (in Danish: "vederlagsfri medicin"). "Free medicine" is medicines for a defined list of diseases and indications that is provided free of charge to patients in outpatient clinics. The paper also describes the content of the various Danish data sources about medicine use, summarizes their strengths and limitations, and exemplifies the ways of evaluating their completeness. An example is provided of the regional variation in the means by which medicines are acquired.

Exposure to antazoline-naphazoline eye drops during pregnancy and the risk of congenital malformations: a Danish nationwide cohort study.

PURPOSE: To investigate whether exposure to antazoline-naphazoline eye drops in the first trimester of pregnancy was associated with an increased risk of malformations in humans. METHODS: All women giving live birth between 1997 and 2011 in Denmark were included in this nationwide cohort study. All women redeeming at least one prescription of antazoline-naphazoline eye drops during the first 84 days of pregnancy were identified. Logistic regression was used to estimate the odds ratios of malformations among exposed offspring compared to non-exposed offspring. RESULTS: We identified 977 706 births between 1997 and 2011. A total of 3061 women (0.32%) were exposed to antazoline-naphazoline eye drops in the first trimester of pregnancy. The rate of congenital malformations was 3.0% (n = 93) in exposed offspring and 3.5% (n = 33 594) in unexposed offspring. First-trimester exposure to antazoline-naphazoline was not associated with major congenital malformations overall (odds ratio: 0.88, 95% confidence interval: 0.71-1.09) or with any specific major malformation. The number of redeemed prescriptions was unchanged during all trimesters of pregnancy as compared to before and after pregnancy (p < 0.05). CONCLUSION: Exposure to antazoline-naphazoline eye drops in the first trimester of pregnancy appears not to be associated with increased teratogenic risk.

Outcomes following calcium channel blocker exposures reported to a poison information center.

BACKGROUND: Calcium channel blockers (CCBs) are widely used drugs that have a narrow therapeutic index. Even minor overdoses must be treated in-hospital due to the risk of severe hypotension and bradycardia. We aimed to describe trends in CCB use and overdoses in Denmark. METHODS: Data on enquiries concerning CCBs reported to the Danish Poisons Information Center (DPIC) from January 2009 to January 2015 was coupled with data on hospitalization and mortality obtained from Danish National Registers. We obtained data on the general use of CCBs in Denmark and retrieved medical charts on fatal cases. RESULTS: From a total of 126,987 enquiries to the DPIC in 2009-2014 we identified 339 CCB unique exposures (3‰ of all). Children < 5 years accounted for 20% all exposures and these were classified as 'intake during playing' (61%) and 'medication errors' (39%). Among adults 'suicidal poisonings' (58%), and 'medication errors' (34%) were most frequent. A majority (81%) of exposures led to hospital admission. Seven patients (2%) died from the CCB exposure and all were adults with 'suicidal poisoning'. Amlodipine accounted for 95% of all CCB prescriptions, was involved in 71% of enquiries and in 29% of fatalities. Verapamil accounted for 3% of prescriptions, was involved in 13% of enquiries and 57% of fatalities. CONCLUSION: Four fifths of enquiries to the DPIC result in hospitalization and one fifth concern small children. Mortality were infrequent and occurred only in adults with suicidal exposures and with and an overrepresentation of verapamil exposures.

The prognosis following amphetamine poisoning.

AIMS: This study investigated the long-term mortality following poisoning by amphetamine or substituted amphetamines. Furthermore, we examined the social problems and somatic and psychiatric co-morbidity related to amphetamine poisoning, and their impact on the long-term survival. METHODS: We identified amphetamine poisoned patients from the Danish Poison Information Centre database and correlated their personal identification numbers with seven Danish national registries related to different social and health aspects. For each case, we sampled 100 age and gender matched controls from the background population. RESULTS: From August 2006 to December 2013 we identified 1444 patients (70% males) who experienced amphetamine poisoning; 52% of the cases were classified as mixed poisonings and the average age at first contact was 24.8 years (SD 8.6). The prevalence of psychiatric disorders, HIV, viral hepatitis, and previous prison incarceration was approximately 10 times higher than among healthy controls. After seven years 11% were deceased as opposed to 0.6% in the control group, and 64% of the patients died from unnatural causes. Male gender (HR 2.29, 95% CI (1.07-4.90)), age (HR 1.06, 95% CI (1.03-1.09)), opioid dependence (HR 2.88, 95% CI (1.42-5.85)), schizophrenia (HR 3.09,95% CI (1.63-5.86)), affective disorders (HR 2.65, 95% CI (1.44-4.90)) and HIV (HR 5.45, 95% CI (1.19-24.90)) were associated with a high mortality. Furthermore, a significant proportion of these patients experienced social and health related deterioration in the years following poisoning. CONCLUSIONS: Amphetamine poisoning is associated with a poor long-term prognosis and is complicated by additional social and health related issues.

Weekly ascorbic acid infusion in castration-resistant prostate cancer patients: a single-arm phase II trial.

BACKGROUND: Ascorbic acid (AA) has in vivo cytotoxic properties at concentrations that can only be achieved through intravenous (IV) administration in humans. Treatment with intravenous AA is widely and increasingly used in complementary medicine despite a lack of clinical evidence for the efficacy of this treatment. METHODS: This non-comparative, single-center, phase II trial included patients with chemotherapy-naïve, metastatic castration-resistant prostate cancer (mCRPC) from an outpatient clinic to evaluate the efficacy and safety of IV AA therapy. Patients received weekly infusions of AA (week 1, 5 g; week 2, 30 g; and weeks 3-12, 60 g) followed by efficacy evaluation at 12 weeks. The primary endpoint for efficacy was a 50% reduction in the prostate-specific antigen (PSA) level. The secondary endpoints included changes in health-related quality of life (HRQoL), biomarkers of bone metabolism, inflammation and bone scans. Clinicaltrials.gov identifier: NCT01080352. RESULTS: Twenty-three patients were enrolled in this study, and 20 completed the efficacy evaluation at 12 weeks. The mean baseline PSA level was 43 µg/L. No patient achieved a 50% PSA reduction; instead, a median increase in PSA of 17 µg/L was recorded at week 12. Among the secondary endpoints, no signs of disease remission were observed. In total, 53 adverse events (AEs) were recorded. Eleven were graded as "serious". Three AEs were directly related to AA, and all of which were related to fluid load. CONCLUSIONS: Infusion with 60 g of AA did not result in disease remission. This study does not support the use of intravenous AA outside clinical trials.

Birth outcomes after exposure to mebendazole and pyrvinium during pregnancy - A Danish nationwide cohort study.

Mebendazole and pyrvinium are anthelmintics used to treat infections with pinworms, a common infection in children. Other indications for treatment with mebendazole are infections with soil-transmitted helminths. These infections are rare in Denmark, but affect more than 1.5 billion people worldwide. Limited safety data of anthelmintics during pregnancy exists and the purpose of this study was to investigate the association between exposure to mebendazole or pyrvinium during pregnancy and the adverse pregnancy outcomes: congenital malformations, stillbirths, neonatal mortality and small for gestational age. The Danish Fertility Database was used to identify all births in Denmark from 1997 to 2007. Maternal exposure to anthelmintics was identified through The Danish Prescription Registry. Of 713667 births, 2567 mothers redeemed a prescription for mebendazole; 1588 for pyrvinium. Logistic regression analysis adjusted for potential confounders. We found no association between exposure to mebendazole and major congenital malformations (OR = 0.7 (CI 95% 0.5-1.1)) or other negative birth outcomes and we found no association between exposure to pyrvinium and major congenital malformations (OR = 0.8 (CI 95% 0.4-1.5)) or other negative birth outcomes. No increased risk was found of having negative birth outcomes after exposure at any trimester during pregnancy.

Long-term Compliance with Oral 5-aminosalicylic Acid Therapy and Risk of Disease Recurrence in Patients with Ulcerative Colitis: A Population-based Cohort Study.

BACKGROUND: Noncompliance to long-term medical therapy is a well-known problem among patients treated for ulcerative colitis, but studies of long-term consequences in unselected patients are lacking. The authors aimed to determine the risk of recurrence according to long-term compliance with oral 5-aminosalicylic acid among unselected patients with ulcerative colitis. METHODS: The authors conducted a 7-year follow-up study of a population-based inception cohort of 243 Danish patients with ulcerative colitis diagnosed from 2003 to 2004. Compliance was defined as consumption of ≥80% of prescribed oral 5-aminosalicylic acid. Data were collected from medical records and the Danish National Prescription Database. They performed Cox regression analysis with adjustments for demographic and clinical characteristics to examine risk of recurrence (defined by increased use of oral 5-Aminosalicylic Acid, other additional treatment, or colectomy) in compliant versus noncompliant patients. RESULTS: In total, 182 patients (75%) experienced at least 1 recurrence during follow-up. For the first year after diagnosis, risk of recurrence did not differ significantly between compliant and noncompliant patients. For 1 to 3 years (hazard ratio: 0.46, 95% CI, 0.33-0.63) and 3 to 8 years (hazard ratio: 0.42, 95% CI, 0.32-0.55) after diagnosis, risk of recurrence was significantly decreased among noncompliant patients compared with that of compliant patients. CONCLUSIONS: This unselected cohort study revealed a reverse association between compliance and recurrence of ulcerative colitis. This is unlikely to be explained by severe confounding because the authors were able to adjust for several demographic and clinical factors. Results may instead reflect that patients during recurrence-free periods through self-management choose not to take their medication.

Diclofenac/misoprostol during early pregnancy and the risk of miscarriage: a Danish nationwide cohort study.

INTRODUCTION: Misoprostol can be used in the prevention of gastric ulcer in treatment with diclofenac and is used in rheumatic diseases. Since misoprostol causes contractions of the uterus, it can also be used to induce abortions when administrated vaginally. The aim of the study was to investigate if early pregnancy exposure to oral diclofenac/misoprostol was associated with miscarriage. METHOD: We conducted a nationwide cohort study identifying all registered pregnancies in Denmark from 1997 to 2011. All births were identified using the Medical Birth Registry, and all records of induced abortion and miscarriage were from the National Hospital Register. Data on drug use were from the National Prescription Register. Cox proportional hazard regression models were used to calculate the hazard of miscarriage in women exposed to diclofenac/misoprostol in early pregnancy. RESULT: We identified 1,338,824 pregnancies (970,491 births, 142,147 miscarriages, 226,145 induced abortions). One hundred sixty-six were exposed to diclofenac/misoprostol in the early pregnancy of which 28.3 % (47) ended up in a miscarriage compared to 10.6 % among unexposed. The adjusted hazard ratio of having a miscarriage after exposure to diclofenac/misoprostol in the first trimester was 3.6 (CI 95 % 2.6-4.9). CONCLUSION: We found an increased risk of miscarriage after exposure to diclofenac/misoprostol during the early pregnancy. Women in the fertile age should not be treated with the combination of diclofenac/misoprostol if other options were available.

Systemic oxidative stress to nucleic acids is unaltered following radioiodine therapy of patients with benign nodular goiter.

BACKGROUND: Little is known about the whole body oxidative stress burden following radioactive iodine ((131)I) therapy of thyroid diseases. METHODS: We studied 17 patients with benign nodular goiter treated with (131)I therapy. The targeted thyroid dose was 50 Gy in 11 patients pretreated with 0.1 mg of recombinant human TSH (rhTSH). In 6 patients, the applied thyroid dose was 100 Gy without rhTSH prestimulation. Well-established biomarkers of oxidative stress to RNA (8-oxo-7,8-dihydroguanosine; 8-oxoGuo) and DNA (8-oxo-7,8-dihydro-2'-deoxyguanosine; 8-oxodG) were measured in freshly voided morning urine (normalized against the creatinine concentration) at baseline, and 7 and 21 days after rhTSH (not followed by (131)I), and 7 and 21 days after (131)I therapy, respectively. RESULTS: The baseline urinary excretions of 8-oxoGuo and 8-oxodG were 2.20 ± 0.84 and 1.63 ± 0.70 nmol/mmol creatinine, respectively. We found no significant changes in the excretion of any of the metabolites, neither after rhTSH stimulation alone nor after (131)I therapy. Also, no significant differences were found between the rhTSH group (low dose, median (131)I: 152 MBq) and the non-rhTSH group (high dose, median (131)I: 419 MBq; 8-oxoGuo: p = 0.66, 8-oxodG: p = 0.71). CONCLUSION: Systemic oxidative stress, as detected by nucleic acids metabolites in the urine, is not increased after thyroid stimulation with 0.1 mg of rhTSH, or after (131)I therapy. Our method cannot quantify the oxidative stress induced locally in the thyroid gland, but the study supports that (131)I therapy of benign nodular goiter carries no or only a minute risk of developing subsequent malignancies. It remains to be explored whether our findings also apply to hyperthyroid disorders.

Exposure to topical chloramphenicol during pregnancy and the risk of congenital malformations: a Danish nationwide cohort study.

PURPOSE: To investigate whether exposure to topical chloramphenicol in the first trimester of pregnancy is associated with congenital malformations. METHODS: The authors conducted a nationwide cohort study including all women giving live birth between 1997 and 2011 in Denmark. All women redeeming at least one prescription of chloramphenicol eye drops or eye ointment during the first 84 days of pregnancy were identified. Logistic regression was used to estimate the odds ratios of malformations among exposed women compared to non-exposed women. RESULTS: 966 372 births between 1997 and 2011 were included. A total of 6024 women were exposed to topical chloramphenicol in the first trimester. The rate of congenital malformations was 3.50% among offspring of exposed mothers and 3.49% among unexposed. Exposure to topical chloramphenicol in the first trimester was not associated with major congenital malformations (adjusted odds ratio = 1.06, 95% CI 0.91-1.22) or specific major malformations. The number of redeemed prescriptions decreased significantly during pregnancy as compared to before and after pregnancy (p < 0.0001). CONCLUSION: In this study, we found no association between dispensing of chloramphenicol eye drops or eye ointment in the first trimester of pregnancy and major congenital malformations. This is in accordance with a previous study analysing the risk of systemic chloramphenicol.

Elimination of ascorbic acid after high-dose infusion in prostate cancer patients: a pharmacokinetic evaluation.

Treatment with high-dose intravenous (IV) ascorbic acid (AA) is used in complementary and alternative medicine for various conditions including cancer. Cytotoxicity to cancer cell lines has been observed with millimolar concentrations of AA. Little is known about the pharmacokinetics of high-dose IV AA. The purpose of this study was to assess the basic kinetic variables in human beings over a relevant AA dosing interval for proper design of future clinical trials. Ten patients with metastatic prostate cancer were treated for 4 weeks with fixed AA doses of 5, 30 and 60 g. AA was measured consecutively in plasma and indicated first-order elimination kinetics throughout the dosing range with supra-physiological concentrations. The target dose of 60 g AA IV produced a peak plasma AA concentration of 20.3 mM. Elimination half-life was 1.87 hr (mean, S.D. ± 0.40), volume of distribution 0.19 L/kg (S.D. ±0.05) and clearance rate 6.02 L/hr (100 mL/min). No differences in pharmacokinetic parameters were observed between weeks/doses. A relatively fast first-order elimination with half-life of about 2 hr makes it impossible to maintain AA concentrations in the potential cytotoxic range after infusion stop in prostate cancer patients with normal kidney function. We propose a regimen with a bolus loading followed by a maintenance infusion based on the calculated clearance.

Urinary markers of nucleic acid oxidation and cancer in type 2 diabetes.

AIMS/HYPOTHESIS: We investigated whether urinary markers of nucleic acid oxidation are associated with an increased risk of cancer in type 2 diabetes patients. METHODS: Urine samples from 1381 newly diagnosed diabetes patients were assayed for the oxidatively modified guanine nucleosides 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo). Cox proportional hazards regression was used to examine the relationship between the urinary markers and cancer incidence. RESULTS: The crude analyses showed an association between overall cancer and urinary excretion of the RNA oxidation marker 8-oxoGuo (unadjusted hazard ratio for cancer per natural log increase in 8-oxoGuo 1.35 [95% CI, 1.01-1.81]), however, in the adjusted analyses, no significant associations between 8-oxodG or 8-oxoGuo and overall cancer were found. For site-specific cancers 8-oxodG was associated with breast cancer in the crude analyses (unadjusted hazard ratio for breast cancer per natural log increase in 8-oxodG was 2.37 [95% CI, 1.07-5.26]), although the association was attenuated in the adjusted analyses (sex- and age-adjusted hazard ratio 2.15 [95% CI, 0.92-5.02] and multivariate adjusted hazard ratio1.98 [95% CI, 0.95-4.10]). CONCLUSIONS: Urinary excretion of the nucleic acid oxidation markers 8-oxodG and 8-oxoGuo at the time of diagnosis was not associated with cancer overall in type 2 diabetes patients. For site-specific cancers, risk elevations were seen for breast cancer (8-oxodG). These findings should be examined in future and larger studies.

Diurnal variation of urinary markers of nucleic acid oxidation.

AIMS: Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo) are biomarkers of oxidative stress with clinical potential in a variety of diseases. As part of their clinical validation, this study aimed to investigate whether the urinary excretion of 8-oxodG and 8-oxoGuo undergoes diurnal variation and to evaluate the validity of 6-hour sampling as well as creatinine corrected spot urine sampling. METHODS: A total of 23 healthy study subjects collecting their 24-h urine in four fractions covering 6 hours each. Urinary 8-oxodG and 8-oxoGuo levels were quantified using a modified version of UPLC-MS/MS. RESULTS: No significant difference in excretion levels between the 12-h diurnal and 12-h nocturnal state or between the four 6-h periods during the day was found for either biomarker. A strong linear relationship between the excretion levels in each of the 6-h periods and the 24-h excretion level was shown for both biomarkers. Creatinine correction of the 6-h levels reduced the biological variation of the excretion levels and weakened the linear relationship with the uncorrected 24-h excretion level for both biomarkers. The correlations were strengthened when the 24-h excretion level was expressed per kg body weight. CONCLUSION: The results showed that 8-oxodG and 8-oxoGuo did not undergo diurnal variation in the study population overall and hence that the time of sampling is not crucial. Furthermore, 6-h sampling can be used as a substitute for 24-h sampling, and creatinine corrected sampling may be rational due to the reduction in biological variation of the biomarkers and the reasonable correlation with body weight-adjusted 24-h levels.

First-trimester exposure to methylphenidate: a population-based cohort study.

OBJECTIVE: The use of methylphenidate to treat attention-deficit/hyperactivity disorder has risen dramatically in Western countries, and it is increasingly used by adults, including women of childbearing age. Very little is known about potential hazards of in utero exposure to methylphenidate. We conducted this study to estimate the risk of major congenital malformations following first-trimester in utero exposure to methylphenidate. METHOD: Data from 2005 to 2012 were extracted from the Danish National Patient Register, the Danish National Prescription Registry, the Medical Birth Registry, and the Danish Civil Registration System. Exposure was defined as having redeemed 1 or more prescriptions for methylphenidate within a time window defined as 14 days before the beginning of the first trimester up to the end of the first trimester. Each exposed subject was propensity score-matched to 10 unexposed subjects with respect to maternal age, smoking status, body mass index, length of education, calendar year of completion of pregnancy, and concomitant use of antipsychotics, antidepressants, anxiolytics, and nonsteroidal anti-inflammatory drugs. RESULTS: We included 222 exposed and 2,220 unexposed pregnancies in the analysis. There was no statistically significant increase in major malformations (point prevalence ratio = 0.8; 95% CI, 0.3-1.8) or cardiac malformations (point prevalence ratio = 0.9; 95% CI, 0.2-3.0). Sensitivity analyses using different definitions of exposure or previous users of methylphenidate as the unexposed comparison cohort yielded comparable results. CONCLUSIONS: First-trimester in utero exposure to methylphenidate does not appear to be associated with a substantially (ie, more than 2-fold) increased overall risk of major congenital malformations.

Association between urinary markers of nucleic acid oxidation and mortality in type 2 diabetes: a population-based cohort study.

OBJECTIVE: We recently showed that RNA oxidation, estimated by urinary excretion of 8-oxo-7,8-dihydroguanosine (8-oxoGuo), independently predicted mortality in a cohort of 1,381 treatment-naive patients with newly diagnosed type 2 diabetes. In the present investigation, we analyzed urine collected 6 years after the diagnosis to assess the association between urinary markers of nucleic acid oxidation and mortality in patients with established and treated diabetes. RESEARCH DESIGN AND METHODS: We used data from the 970 patients who attended the screening for diabetes complications 6 years after the diagnosis. Cox proportional hazards regression was used to examine the relationship between urinary markers of DNA oxidation (8-oxo-7,8-dihydro-2'-deoxyguanosine [8-oxodG] [n = 938]) and RNA oxidation (8-oxoGuo [n = 936]) and mortality. RESULTS: During a median of 9.8 years of follow-up, 654 patients died. Urinary 8-oxoGuo assessed 6 years after the diagnosis was significantly associated with mortality. The multivariate-adjusted hazard ratios for all-cause and diabetes-related mortality of patients with 8-oxoGuo levels in the highest quartile compared with those in the lowest quartile were 1.86 (95% CI 1.34-2.58) and 1.72 (1.11-2.66), respectively. Conversely, 8-oxodG was not associated with mortality. In addition, we found an association between changes in 8-oxoGuo from diagnosis to 6-year follow-up and mortality, with increased risk in patients with an increase and decreased risk in patients with a decrease in 8-oxoGuo. CONCLUSIONS: The RNA oxidation marker 8-oxoGuo is an independent predictor of mortality in patients with established and treated type 2 diabetes, and changes in 8-oxoGuo during the first 6 years after diagnosis are associated with mortality.

Effect of specific ADRB1/ADRB2/AGT genotype combinations on the association between survival and carvedilol treatment in chronic heart failure: a substudy of the ECHOS trial.

OBJECTIVES: The aim of the present study was to determine whether carvedilol-treated chronic heart failure patients have a different prognosis when stratified for a specific combination of a gain-of-function genotype of the adrenergic ß-1 receptor gene (ADRB1) (Arg389-homozygous), two gain-of-function genotypes of the angiotensinogen gene (AGT) (Thr174-homozygous and Thr235-homozygous), and a downregulated genotype of the adrenergic ß-2 receptor gene (ADRB2) (Gln27-carrier). METHODS: Genotyping of 618 patients was carried out using the Sequenoms MassARRAY genotyping system. Outcome was all-cause mortality and statistics were calculated using a multivariable Cox proportional hazards model. Internal validation was performed using the bootstrap procedure. RESULTS: Eighty-seven of the 618 patients included in the study were treated with carvedilol. There was a significant interaction between the outcome of carvedilol treatment and the combination of the gain-of-function ADRB1 genotype (Arg389-homozygous) and the gain-of-function AGT genotype (Thr174-homozygous) (P(interaction)=0.003; hazard ratio 2.19, 95% confidence interval 1.26-3.78, P=0.005). There was also a significant interaction when the downregulated ADRB2 genotype (Gln27-carrier) was added to the ADRB1/AGT combination (P(interaction)=0.0005; hazard ratio 2.67, 95% confidence interval 1.51-4.72, P=0.0007). Two hundred and four patients were treated with metoprolol. There was no interaction between metoprolol treatment and the specific genotype combinations as there was no difference in the overall survival. The validity of the results was supported by the bootstrap procedure. CONCLUSION: We found a doubling of the hazard of mortality in carvedilol-treated patients with the combination of the gain-of-function ADRB1 genotype (Arg389-homozygous), the gain-of-function AGT genotype (Thr174-homozygous), and the downregulated ADRB2 genotype (Gln27-carrier). This might be valuable when stratifying chronic heart failure patients to the right ß-blocker therapy.

Effect of the Arg389Gly ß1-adrenoceptor polymorphism on plasma renin activity and heart rate, and the genotype-dependent response to metoprolol treatment.

1. A gene-drug interaction has been indicated between ß1-adrenoceptor-selective beta-blockers and the Arg389Gly polymorphism (rs1801253) in the adrenergic beta-1 receptor gene (ADRB1). In the present study, we investigated the effect of the ADRB1 Arg389Gly polymorphism on plasma renin activity (PRA) and heart rate (HR), as well as genotype-dependent responses to metoprolol and exercise. 2. Twenty-nine healthy male subjects participated in two treatment periods (placebo and 200 mg/day metoprolol). A 15 min submaximal exercise test was performed after each treatment period and PRA and HR were measured before and after exercise. 3. Before exercise, median PRA was lower in Gly/Gly subjects than in Arg/Arg subjects after both placebo (P = 0.030) and metoprolol (P = 0.020) treatment. After placebo, the exercise-induced increase in PRA was greater in Gly/Gly than Arg/Gly and Arg/Arg subjects (P = 0.033). The linear association between log(PRA) and log(metoprolol concentration) varied significantly between genotypes (P = 0.024). In Gly/Gly subjects, PRA decreased significantly with metoprolol concentration before (P = 0.025) and after exercise (P < 0.001), whereas in Arg/Gly and Arg/Arg subjects metoprolol concentration had no effect on PRA. The effect of metoprolol concentration on PRA in Gly/Gly subjects was enhanced by exercise (P = 0.044). No significant differences in HR were seen between genotype groups. 4. Resting PRA was lower in Gly/Gly than Arg/Arg subjects and the effect of exercise and metoprolol concentration on PRA was stronger in Gly/Gly subjects than with the other two genotypes. Thus, Gly/Gly heart failure patients may require lower doses of metoprolol than other patients to block neurohumoral hyperactivity.

Urinary markers of nucleic acid oxidation and long-term mortality of newly diagnosed type 2 diabetic patients.

OBJECTIVE: We analyzed data from a cohort of 1,381 newly diagnosed type 2 diabetic patients to test the hypothesis that urinary markers of nucleic acid oxidation are independent predictors of mortality. RESEARCH DESIGN AND METHODS: We examined the relationship between urinary excretion of markers of DNA oxidation (8-oxo-7,8-dihydro-2'-deoxyguanosine [8-oxodG]) and RNA oxidation (8-oxo-7,8-dihydroguanosine [8-oxoGuo]) and long-term mortality using Cox proportional hazards regression. RESULTS: After multivariate adjustment, the hazard ratios for all-cause and diabetes-related mortality of patients with 8-oxoGuo levels in the highest quartile compared with those in the lowest quartile were 1.44 (1.12-1.85) and 1.54 (1.13-2.10), respectively. Conversely, no significant associations between 8-oxodG and mortality were found in the adjusted analyses. CONCLUSIONS: Urinary excretion of the RNA oxidation marker 8-oxoGuo measured shortly after diagnosis of type 2 diabetes predicts long-term mortality independently of conventional risk factors. This finding suggests that 8-oxoGuo could serve as a new clinical biomarker in diabetes.

Long-term effects of Irbesartan treatment and smoking on nucleic acid oxidation in patients with type 2 diabetes and microalbuminuria: an Irbesartan in patients with type 2 diabetes and Microalbuminuria (IRMA 2) substudy.

OBJECTIVE: We tested whether long-term treatment with the angiotensin II receptor antagonist irbesartan reduces nucleic acid oxidation in patients with type 2 diabetes and microalbuminuria. RESEARCH DESIGN AND METHODS: The Irbesartan in Patients With Type 2 Diabetes and Microalbuminuria (IRMA 2) study was a 2-year multicenter randomized double-blind trial comparing irbesartan (150 and 300 mg once daily) with placebo. We studied a subgroup of 50 patients where urine samples were available for analysis of albumin and the oxidatively modified guanine nucleosides 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo). RESULTS: During the 2-year trial, no significant differences in 8-oxodG and 8-oxoGuo excretions between placebo and irbesartan treatment were seen. 8-oxodG and albumin excretion decreased with time (P = 0.0004 and P < 0.0001, respectively), whereas treatment-related differences were shown for albumin excretion (P = 0.0008) only, as previously reported. Important secondary findings were significant associations between changes in 8-oxodG excretion and changes in albumin excretion and glycated hemoglobin (HbA(1c)). During the study period, 8-oxodG excretion decreased by 3 and 26% in smokers and nonsmokers, respectively (P = 0.015), and urinary albumin excretion decreased 22% in smokers and 58% in nonsmokers (P = 0.011). CONCLUSIONS: Irbesartan treatment was not significantly more effective than placebo in reducing nucleic acid oxidation. The results indicate that DNA oxidation in diabetes patients is reduced by various components in the treatment of diabetes where glycemic control seems to be important and addition of angiotensin II receptor antagonists does not lead to any substantial additional reduction. Furthermore, the reductions in DNA oxidation and albumin excretion seem to be counteracted by smoking.