Low antimicrobial resistance in general practice patients in Rotterdam, the city with the largest proportion of immigrants in the Netherlands.

Antimicrobial resistance (AMR) is an increasing problem. The prevalence of antimicrobial resistance in general practice patients is expected to be relatively high in Rotterdam, the Dutch city with the largest proportion non-Western immigrants. The aim of this study was to assess the prevalence of antibiotic-resistant uropathogens (Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis) in general practices in Rotterdam, and to find a possible association between the prevalence of antibiotic-resistant E. coli and age, gender, and socioeconomic status (SES). A retrospective analysis was performed of urine samples from general practice patients in 2016. The prevalence of AMR in uropathogens was compared with national resistance data, as was the prevalence of highly and multidrug resistant and extended spectrum ß-lactamase (ESBL) producing E. coli and K. pneumoniae. Univariate logistic regression was used to study associations between antibiotic-resistant E. coli and age, gender, and SES area score. No clinically relevant differences were observed in the prevalence of antibiotic-resistant uropathogens in Rotterdam compared with the national prevalence. For E. coli and K. pneumoniae, the prevalence was 3.6% for ESBL production (both pathogens together), while the prevalence ranged between 4.2%-5.0% for high resistance and between 1.2%-3.3% for multidrug resistance. Ciprofloxacin-resistant E. coli was significantly associated with higher age. Although Rotterdam has a high percentage of non-western immigrants and a low SES, AMR is low among general practice patients. This indicates that adherence to national guidelines in general practice enables maintenance of low AMR, even in high-risk populations.

The rs13064411 polymorphism in the WDR52 gene, associated with PCSK9 levels, modifies statin-induced changes in serum total and LDL cholesterol levels.

OBJECTIVE: Recently, the minor allele of the rs13064411A>G polymorphism in the WD repeat domain 52 (WDR52) gene was associated with increased statin-induced proprotein convertase subtilisin/kexin type 9 (PCSK9) levels and with LDL cholesterol response to statins. PCSK9 promotes LDL receptor degradation, leading to increased serum LDL cholesterol. We investigated whether the polymorphism was associated with cholesterol response to statins. METHODS: We identified 1105 current, 322 past, and 4831 never statin users during follow-up in the prospective population-based Rotterdam Study. The mean delta total, LDL, and HDL cholesterol levels between current and no current statin users with the same number of minor alleles were analyzed using random-effect repeated measurements. We adjusted for age, sex, number of cholesterol measurements, and follow-up time. RESULTS: Compared with no users with the same genotype, current statin users carrying a minor allele showed a statistically significantly lower delta total and LDL cholesterol compared with reference homozygous major allele carriers [total: Δ=0.551 mmol/l (AG+GG) vs. Δ=0.732 mmol/l (AA), Pinteraction: 5.2×10(-7); LDL: Δ=0.566 mmol/l (AG+GG) vs. Δ=0.720 mmol/l (AA), Pinteraction: 1.8×10(-5)]. The effect was stronger in women (Pinteraction: 2.0×10(-5) for LDL cholesterol, 8.0×10(-6) for total cholesterol) and in high-dose users (defined daily doses>1.00) (Pinteraction: 7.0×10(-5) for LDL cholesterol, Pinteraction: 0.081 for total cholesterol). The polymorphism was not associated with HDL cholesterol in current statin users, or with total, LDL and HDL cholesterol in never statin users. CONCLUSION: The minor G allele of the rs13064411 polymorphism, associated with statin-induced PCSK9-levels, was associated with a decreased LDL-lowering and total cholesterol-lowering response to statins.

Thiazide-associated hyponatremia: a population-based study.

BACKGROUND: Hyponatremia is one of the most common adverse reactions to thiazide diuretics. In the present study, we analyzed differences in thiazide-associated hyponatremia between men and women and between different categories of age, body mass index (BMI), daily thiazide dose, and estimated glomerular filtration rate. STUDY DESIGN: Population-based cohort study. SETTING & PARTICIPANTS: 13,325 individuals 45 years and older living in a suburb of Rotterdam, as part of the Rotterdam Study. PREDICTOR: Exposure to thiazide diuretics. OUTCOMES: The association between thiazide exposure and hyponatremia (defined as sodium level ≤135 mmol/L; mild hyponatremia, 130-≤135 mmol/L; moderate, >125-<130 mmol/L; and severe, ≤125 mmol/L) was studied in a period covering more than 10 years using Cox proportional hazard regression analyses. RESULTS: 718 participants used thiazides at baseline, and 2,738 participants started on thiazide therapy during follow-up. 522 participants developed hyponatremia, of whom 32.4% were exposed to thiazide diuretics at the time of hyponatremia. Thiazide exposure was associated with an almost 5 times higher risk of hyponatremia than no exposure (HR, 4.95; 95% CI, 4.12-5.96). The risk of mild hyponatremia was more than 4.5 times higher in thiazide-exposed individuals; risks of moderate and severe hyponatremia were both 8 times higher in individuals exposed to thiazides. Age and BMI (but not sex [P = 0.8] or estimated glomerular filtration rate [P = 0.2]) significantly modified this risk of thiazide-associated hyponatremia (P < 0.05). LIMITATIONS: Some cases of severe hyponatremia may have been missed if patients were admitted to the hospital without assessment of serum sodium in the general practitioner's laboratory. Nonproportionality of hazards in the first period was explained as possible "depletion of susceptibles" in this closed cohort. CONCLUSIONS: Thiazide use is associated with a substantially increased risk of hyponatremia. Age and BMI significantly influenced the thiazide-associated risk of hyponatremia.

Screening for type 2 diabetes in a high-risk population: study design and feasibility of a population-based randomized controlled trial.

BACKGROUND: We describe the design and present the results of the first year of a population-based study of screening for type 2 diabetes in individuals at high risk of developing the disease. High risk is defined as having abdominal obesity. METHODS: Between 2006 and 2007, 79,142 inhabitants of two Dutch municipalities aged 40-74 years were approached to participate in screening. Eligible participants had a self-reported waist circumference of ≥ 80 cm for women and ≥ 94 cm for men, and no known pre-existing diabetes. Of the respondents (n = 20,578; response rate 26%), 16,135 were abdominally obese. In total, 10,609 individuals gave written informed consent for participation and were randomized into either the screening (n = 5305) or the control arm (n = 5304). Participants in the screening arm were invited to have their fasting plasma glucose (FPG) measured and were referred to their general practitioner (GP) if it was ≥ 6.1 mmol/L. In addition, blood lipids were determined in the screening arm, because abdominal obesity is often associated with cardiovascular risk factors. Participants in both arms received written healthy lifestyle information. Between-group differences were analyzed with Chi-square tests and logistic regression (categorical variables) and unpaired t-tests (continuous variables). RESULTS: The screening attendance rate was 84.1%. Attending screening was associated with age at randomization (OR = 1.03, 95% CI 1.02-1.04), being married (OR = 1.57, 95% CI 1.33-1.83) and not-smoking currently (OR = 0.52, 95% CI 0.44-0.62). Of the individuals screened, 5.6% had hyperglycemia, and a further 11.6% had an estimated absolute cardiovascular disease risk of 5% or higher, according to the Systematic Coronary Risk Evaluation risk model. These participants were referred to their GP. CONCLUSIONS: Self-reported home-assessed waist circumference could feasibly detect persons at high risk of hyperglycemia or cardiovascular disease. Continuation of the large-scale RCT is warranted to test the hypothesis that targeted population-based screening for type 2 diabetes leads to a significant reduction in cardiovascular morbidity and mortality. TRIAL REGISTRATION: ISRCTN75983009.

Prostate-specific antigen-based prostate cancer screening: reduction of prostate cancer mortality after correction for nonattendance and contamination in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer.

BACKGROUND: Large randomized screening trials provide an estimation of the effect of screening at a population-based level. The effect of screening for individuals, however, is diluted by nonattendance and contamination in the trial arms. OBJECTIVE: To determine the prostate cancer (PCa) mortality reduction from screening after adjustment for nonattendance and contamination. DESIGN, SETTING, AND PARTICIPANTS: A total of 34,833 men in the core age group, 55-69 yr, were randomized to a screening or control arm in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer (ERSPC). Prostate-specific antigen (PSA) testing was offered to all men in the screening arm at 4-yr intervals. A prostate biopsy was offered to men with an elevated PSA. The primary end point was PCa-specific mortality. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Nonattendance was defined as nonparticipation in the screening arm. Contamination in the control arm was defined as receiving asymptomatic PSA testing or a prostate biopsy in the absence of symptoms. Relative risks (RRs) were calculated with an intention to screen (ITS) analysis and after correction for nonattendance and contamination using a method that preserves the benefits obtained by randomization. RESULTS AND LIMITATIONS: The ITS analysis resulted in an RR of 0.68 (95% confidence interval [CI], 0.53-0.89) in favor of screening at a median follow-up of 13 yr. Correction for both nonattendance and contamination resulted in an RR of 0.49 (95% CI, 0.27-0.87) in favor of screening. CONCLUSIONS: PCa screening as conducted in the Rotterdam section of the ERSPC can reduce the risk of dying from PCa up to 51% for an individual man choosing to be screened repeatedly compared with a man who was not screened. This benefit of screening should be balanced against the harms of overdiagnosis and subsequent overtreatment. TRIAL REGISTRATION: ISRCTN49127736.

Thiazides and the risk of hypokalemia in the general population.

OBJECTIVES: Hypokalemia is a frequent adverse reaction to thiazide diuretics, but is often asymptomatic. However, even asymptomatic hypokalemia may contribute to chronic disabilities and mortality. The aim of this study was to assess the risk of thiazide-induced hypokalemia in men and women in the general population. METHODS: Within the Rotterdam study, which is a population-based cohort study, the association between thiazide exposure and hypokalemia (serum potassium level <3.5 mmol/l; moderate to severe ≤3.0 mmol/l) was studied using Cox proportional-hazard regression analysis over a 10-year period, with thiazide use as a time-varying exposure. RESULTS: During follow-up, 507 cases of hypokalemia occurred in 13, 328 patients. Thiazide use was associated with an 11 times higher risk of hypokalemia than no use [relative risk (RR) 11.18, 95% confidence interval (CI) 8.95, 13.96] after adjustment for sex, age, and use of a renin-angiotensin system (RAS) inhibitor or separate potassium-sparing diuretic. In users of a thiazide in combination with triamterene, the risk was still six times higher (RR 5.93, 95% CI 4.65, 7.55) than in nonusers. The risk of thiazide-induced hypokalemia was significantly higher in men than in women and changed significantly with age and dosage. The risk of moderate to severe hypokalemia was almost five times higher in thiazide users (RR 4.80, 95% CI 2.61, 8.84) than in nonusers. CONCLUSION: The risk of thiazide-induced hypokalemia is high, and more than twice as high in men as in women. Hypokalemia risk is influenced by age and dosage, and is still increased if used in combination with triamterene.

Genetic variation in the PPARA gene is associated with simvastatin-mediated cholesterol reduction in the Rotterdam Study.

AIM: Recently, minor alleles of two strongly linked polymorphisms in the PPARA gene, rs4253728 G>A and rs4823613 A>G, were related to decreased CYP3A4 expression and activity. We studied whether they were associated with the cholesterol-lowering effect of simvastatin. MATERIALS & METHODS: We identified 123 incident users with cholesterol measurements before and after starting statin therapy in a prospective population-based cohort study. Associations between PPARA polymorphisms and change in total and low-density lipoprotein (LDL)-cholesterol levels were analyzed using linear regression. RESULTS: The minor G allele of the rs4823613 A>G polymorphism was associated with a 0.258 mmol/l (95% CI: -0.470 to -0.046) and a 0.294 mmol/l (95% CI: -0.495 to -0.093) larger reduction in total and LDL-cholesterol, respectively, after starting simvastatin therapy. Results were similar for the rs4253728 G>A polymorphism. CONCLUSION: The minor alleles of the PPARA rs4253728 and rs4823613 polymorphisms are associated with a better total and LDL-cholesterol-lowering response to simvastatin, possibly through influence on CYP3A4.

Feasibility study of adjustment for contamination and non-compliance in a prostate cancer screening trial.

BACKGROUND: The use of PSA as a screening test has become increasingly prevalent in the general population and therefore also in the control arm of the European Randomized study of Screening for Prostate Cancer (ERSPC). We present a feasibility study and impact simulation of a secondary analysis, which imitates a situation where all participants in the study are managed according to their random assignment. METHODS: The results of the Rotterdam section of the ERSPC were adjusted for contamination and non-compliance according to Cuzick et al. [Stat Med 1997; 16:1017-1029]. Endpoints of this analysis were simulated reductions in prostate cancer mortality. RESULTS: Of the men allocated to the screen arm, 27.1% were non-compliant. In the control arm 30.7% had their PSA-level measured by a general practitioner (GP) (i.e., contamination). For a scenario in which the intention-to-screen analysis was assumed to give a decrease in the mortality in the men randomized to screening of 6.7%, the secondary analysis resulted in a decrease of 16.1% for those actually screened. CONCLUSION: Although the definition of contamination as "PSA ever tested" gives an indication of the proportion of contamination, it will be important to differentiate the screening use of PSA from its diagnostic use. For the rest, adjustment for non-compliance and contamination was shown to be feasible in this prostate cancer screening trial. It can therefore be used to carry out a secondary analysis on the definitive outcome of the ERSPC and will provide accurate information for those men who are in fact screened.

Effective PSA contamination in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer.

The extent of effective prostate-specific antigen (PSA) contamination in the Rotterdam section of the ongoing European Randomized Study of Screening for Prostate Cancer (ERSPC) trial was evaluated and defined as when opportunistic PSA testing of >/= 3.0 ng/ml was followed by biopsy, similar to the regular procedure within the trial. Records of participants aged 55-74 years at entry were linked to the regional database of the general practitioner (GP) laboratory to obtain PSA tests requested by GPs in the period 1 July 1997 to 31 May 2000 (2.9 years), and to the national pathology database to quantify the number of biopsies. All men randomized were included, only those with prostate cancer screen-detected or clinically diagnosed before July 1997 were omitted from the analyses. 2,895 out of the 14,349 men (20.2%) in the control arm and 1,981 out of the 14,052 men (14.1%) in the screening arm were PSA-tested, at an average annual rate of 73 and 52 per 1,000 person-years, respectively. These rates were higher than those recorded at the national and regional levels, 33 and 38 per 1,000 person-years, respectively. Opportunistic PSA testing in the control arm reached a peak within the first months of randomization, after which it decreased to around 70 per 1,000 person-years. An opposite pattern was observed in the screening arm, where participants already had received the scheduled screening within the trial. The proportion of men in the control arm with PSA >/= 3.0 ng/ml followed by biopsy and prostate cancer was 7-8% and 3%, respectively (3% and 0.4-0.6% in the screening arm), over the whole study period. Over a 4-year rescreening interval, the average PSA and effective contamination amount were approximately 28% and 10%, respectively. PSA testing in the control arm in the Rotterdam ERSPC section is high, but was not followed by a substantial increase in prostate biopsies. Although the reasons for ordering PSA test or indicating biopsy are unknown, effective PSA contamination in the Rotterdam ERSPC section is low and not likely to jeopardize the power of the trial.