Risk of misclassification with a non-fasting lipid profile in secondary cardiovascular prevention.

AIMS: Routinely fasting is not necessary for measuring the lipid profile according to the latest European consensus. However, LDL-C tends to be lower in the non-fasting state with risk of misclassification. The extent of misclassification in secondary cardiovascular prevention with a non-fasting lipid profile was investigated. METHODS AND RESULTS: 329 patients on lipid lowering therapy for secondary cardiovascular prevention measured a fasting and non-fasting lipid profile. Cut-off values for LDL-C, non-HDL-C and apolipoprotein B were set at <1.8mmol/l, <2.6mmol/l and <0.8g/l, respectively. Study outcomes were net misclassification with non-fasting LDL-C (calculated using the Friedewald formula), direct LDL-C, non-HDL-C and apolipoprotein B. Net misclassification <10% was considered clinically irrelevant. Mean age was 68.3±8.5years and the majority were men (79%). Non-fasting measurements resulted in lower LDL-C (-0.2±0.4mmol/l, P<0.001), direct LDL-C (-0.1±0.2mmol/l, P=0.001), non-HDL-C (-0.1±0.4mmol/l, P=0.004) and apolipoprotein B (-0.02±0.10g/l, P=0.004). 36.0% of the patients reached a fasting LDL-C target of <1.8mmol/l with a significant net misclassification of 10.7% (95% CI 6.4-15.0%) in the non-fasting state. In the non-fasting state net misclassification with direct LDL-C was 5.7% (95% CI 2.1-9.2%), 4.0% (95% CI 1.0-7.4%) with non-HDL-C and 4.1% (95% CI 1.1-9.1%) with apolipoprotein B. CONCLUSION: Use of non-fasting LDL-C as treatment target in secondary cardiovascular prevention resulted in significant misclassification with subsequent risk of undertreatment, whereas non-fasting direct LDL-C, non-HDL-C and apolipoprotein B are reliable parameters.

Inappropriate benzodiazepine use in older adults and the risk of fracture.

AIMS: The Beers criteria for prescribing in elderly are well known and used for many drug utilization studies. We investigated the clinical value of the Beers criteria for benzodiazepine use, notably the association between inappropriate use and risk of fracture. METHODS: We performed a nested case-control study within the Rotterdam Study, a population-based cohort study in 7983 elderly. The proportion of 'inappropriate' benzodiazepine use according to the Beers criteria was compared between fracture patients and controls. 'Inappropriate' use for elderly implies use of some long-acting benzodiazepines and some intermediate/short-acting ones exceeding a suggested maximum daily dose. Also, alternative criteria were applied to compare the risk of fracture. Cases were defined as persons with incident fracture between 1991 and 2002 who were current benzodiazepine users on the fracture date. Controls were matched on fracture date and were also current benzodiazepine users. RESULTS: The risk of fracture in 'inappropriate' benzodiazepine users according to the Beers criteria was not significantly different from 'appropriate' users [odds ratio (OR) 1.07, 95% confidence interval (CI) 0.72, 1.60]. However, a significantly higher risk of fracture was found in 'high dose' users and a longer duration of use (14-90 days), irrespective of the type of benzodiazepine (OR 3.45, 95% CI 1.38, 8.59). CONCLUSIONS: These findings suggest that inappropriate benzodiazepine use according to the Beers criteria is not associated with increased risk of fracture. Daily dose and longer duration of use (>14 days) is associated with higher risk of fracture, irrespective of the type of benzodiazepine prescribed.

Estrogen receptor alpha gene polymorphisms are associated with estradiol levels in postmenopausal women.

OBJECTIVE: Postmenopausal estradiol (E(2)) levels vary widely between individuals and this variation is an important determinant of diseases such as osteoporosis. It has been suggested that the estrogen receptor alpha (ESR1) gene may influence peripheral E(2) levels, but the role of common sequence variations in the ESR1 gene is unclear. METHODS: In 631 postmenopausal women and 528 men from the Rotterdam Study, a population-based, prospective cohort study of individuals aged 55 years and over, ESR1 PvuII-XbaI haplotypes were determined and correlated with plasma E2 levels. RESULTS: In women, haplotype 1 (T-A) was significantly associated with an allele-dose-dependent decrease in E(2). After adjusting for age, body mass index, years since menopause and testosterone levels, plasma E(2) levels decreased by 1.90 pmol/l per allele copy of this haplotype (P < 0.05). Extreme genotypes, representing 23 and 27% of the population, varied by 3.93 pmol/l. No association with plasma testosterone was observed. In a subset of 446 women, no association of genotype with plasma concentrations of dehydroepiandrosterone sulfate, androstenedione or estrone was seen. In men, none of the sex hormone levels was associated with the ESR1 PvuII-XbaI haplotypes. CONCLUSION: We have demonstrated a role for genetic variations in the ESR1 gene in determining post-menopausal E(2) levels in women.

ApoE gene polymorphisms, BMD, and fracture risk in elderly men and women: the Rotterdam study.

UNLABELLED: To study the association between the ApoE gene polymorphism and osteoporosis, we performed an association study in 5,857 subjects from the Rotterdam Study. We did not observe an association between the ApoE polymorphism and osteoporosis in this study, which is thus far the largest study on ApoE and osteoporosis. INTRODUCTION: The E*4 allele of the E*2, E*3, E*4 protein isoform polymorphism in the gene encoding apolipoprotein E (ApoE) has previously been associated with an increased fracture risk. We investigated the association between the ApoE polymorphism and BMD, bone loss, and incident fractures as part of the Rotterdam Study a prospective population-based cohort study of diseases in the elderly. MATERIALS AND METHODS: The study population consisted of 5,857 subjects (2,560 men; 3,297 women) for whom data on ApoE genotypes, confounding variables, and follow-up of nonvertebral fractures were available. Data on femoral neck and lumbar spine BMD were available for 4,814 participants. Genotype analyses for bone loss (defined as annualized percent change in BMD at the hip and lumbar spine) and BMD were performed using ANOVA. Fractures were analyzed using a Cox proportional-hazards model and logistic regression. All relative risks were adjusted for age and body mass index. RESULTS AND CONCLUSIONS: The genotype distribution of the study population was in Hardy-Weinberg equilibrium (p = 0.98) and did not differ by gender. At baseline, mean BMD of the lumbar spine and femoral neck did not differ between the ApoE genotypes of men and women. Bone loss (mean follow-up, 2.0 years) did not differ by ApoE genotype for women and men. During a mean follow-up of 6.6 years, 708 nonvertebral fractures (198 hip fractures and 179 wrist fractures) and 149 incident vertebral fractures occurred. No consistent differences in the distribution of alleles could be observed between subjects with or without these fractures. Our data do not support the hypothesis that the ApoE*4 risk allele is associated with BMD, increased bone loss, or an increased risk of osteoporotic fractures.

HMG-CoA reductase inhibitors and the risk of vertebral fracture.

UNLABELLED: Statins inhibit an enzyme in the mevalonate pathway and therefore may affect bone. In this first study on both symptomatic and nonsymptomatic vertebral fractures in the elderly (N = 3469), we show that long-term statin use is significantly associated with a 50% lower vertebral fracture risk. Randomized trials on statins and fractures, carried out in populations at risk for fractures, are needed. INTRODUCTION: Statins are cholesterol-lowering agents that could potentially affect bone. Previous studies on statin use and fracture risk reported contradictory results and did not include both symptomatic and nonsymptomatic vertebral fractures. MATERIALS AND METHODS: To examine the association between statin use, vertebral fractures, and lumbar spine BMD, we performed a prospective population-based cohort study in men and women (N = 3469) > or =55 years of age. These individuals had both baseline and follow-up spinal X-rays available. Statin use was obtained from detailed computerized pharmacy data, and the total number of days of exposure before second X-ray was calculated. A multivariate logistic regression model was fitted to calculate odds ratios and CIs. RESULTS: During a mean follow-up of 6.5 years, 176 incident vertebral fractures occurred. There were 508 statin users and 16 exposed cases. The adjusted relative risk for incident vertebral fracture in users of statins (compared with nonusers) was 0.58 (95% CI, 0.34-0.99). The relative risk decreased on higher cumulative use to 0.52 (95% CI, 0.28-0.97) for use for more than 365 days during the study period. Use of (the hydrophilic statin) pravastatin and use of nonstatin cholesterol-lowering drugs was not significantly associated with vertebral fracture risk. Statin use was not significantly associated with lumbar spine BMD. CONCLUSION: Statin use is associated with a lower risk of vertebral fracture. Randomized clinical trials in a population at risk for fracture are needed to examine this association.

Thiazide diuretics and the risk for hip fracture.

BACKGROUND: Since most hip fractures are related to osteoporosis, treating accelerated bone loss can be an important strategy to prevent hip fractures. Thiazides have been associated with reduced age-related bone loss by decreasing urinary calcium excretion. OBJECTIVE: To examine the association between dose and duration of thiazide diuretic use and the risk for hip fracture and to study the consequences of discontinuing use. DESIGN: Prospective population-based cohort study. SETTING: The Rotterdam Study. PARTICIPANTS: 7891 individuals 55 years of age and older. MEASUREMENTS: Hip fractures were reported by the general practitioners and verified by trained research assistants. Details of all dispensed drugs were available on a day-to-day basis. Exposure to thiazides was divided into 7 mutually exclusive categories: never use, current use for 1 to 42 days, current use for 43 to 365 days, current use for more than 365 days, discontinuation of use since 1 to 60 days, discontinuation of use since 61 to 120 days, and discontinuation of use since more than 120 days. RESULTS: 281 hip fractures occurred. Relative to nonuse, current use of thiazides for more than 365 days was statistically significantly associated with a lower risk for hip fracture (hazard ratio, 0.46 [95% CI, 0.21 to 0.96]). There was no clear dose dependency. This lower risk disappeared approximately 4 months after thiazide use was discontinued. CONCLUSIONS: Thiazide diuretics protect against hip fracture, but this protective effect disappears within 4 months after use is discontinued.