Mortality, kidney disease and cardiac procedures following acute coronary syndrome.

BACKGROUND: Cardiac interventions are underutilized in patients with chronic kidney disease (CKD) following acute coronary syndrome (ACS) partly due to nephrotoxicity concerns. METHODS: We analyzed outcomes of 4631 subjects with ACS enrolled in the Blockade of the Glycoprotein IIb/IIIa Receptor to Avoid Vascular Occlusion trial, including time to death, time to reduced renal function (50% reduction in estimated glomerular filtration rate (eGFR) or development of end-stage renal disease (ESRD)) and percent change in eGFR from baseline. RESULTS: Subjects with a lower baseline eGFR were more likely to be older, female and have diabetes, hypertension, congestive heart failure or peripheral vascular disease (all P < 0.0001); they were less likely to be taking aspirin > or = 162 mg or to have undergone a percutaneous coronary intervention (PCI) prior to enrollment (P < 0.0001). As eGFR declined, the proportion of subjects experiencing death versus reduced eGFR or ESRD qualitatively increased. In adjusted analyses, every 10 ml/min/1.73 m(2) decrease in eGFR < or = 90 was associated with a 15% increased hazard of death (HR 1.15, P = 0.01). In adjusted analyses of predictors of percent change in eGFR, catheterization (cath) with or without PCI compared to medical therapy during follow-up was not associated with significant differences in long-term eGFR (P = 0.09). CONCLUSIONS: Among CKD subjects in this study, the risk of death greatly outweighed the risk of reduced eGFR or development of ESRD following ACS and the occurrence of cath +/- PCI was not associated with significant differences in long-term renal function. The presence of CKD should not preclude potentially beneficial interventions and research should focus on reducing the high cardiovascular burden in this population.     

Prevalence of ventricular conduction blocks in the resting electrocardiogram in a general population: The Health 2000 Survey

Aims

The prevalence of eight different ventricular conduction blocks and their association with risk factors and major cardiovascular diseases were studied in a major Finnish population study.

Methods

Data, including 12-lead electrocardiograms, were collected from 6315 subjects. The prevalence of left bundle branch block (LBBB), right bundle branch block (RBBB), non-specific ventricular block, incomplete LBBB, incomplete RBBB, R–R′-pattern, left anterior hemiblock (LAHB), and left posterior hemiblock (LPHB) was calculated for both genders in three age groups. Their association with risk factors and cardiovascular diseases was studied.

Results

R–R′-pattern was the most common ventricular conduction block in all age groups (3.9%, p < 0.001 for comparison between groups), but it showed no association with cardiovascular diseases. Males had more RBBB (1.5% vs. 0.7%, p < 0.001), incomplete LBBB (1.8 vs. 0.4, p < 0.001) and non-specific ventricular block (1.1% vs. 0.1%, p < 0.001).With increasing age (< 45 years vs. > 55 years) LBBB, RBBB and LAHB (0 vs. 2.2%, 0.3 vs. 2.2%, 0.2 vs. 1.9% respectively, p-values < 0.001) became more prevalent. LBBB, RBBB and non-specific ventricular conduction block were associated with coronary heart disease (angina pectoris in 28.3, 20.3 and 22.9%, respectively) and heart failure (25.0, 10.1 and 11.4%, respectively). LBBB and RBBB were also associated with peripheral vascular disease (8.8%).

Conclusions

Ventricular conduction blocks differ in prevalence between sexes and age groups. They also show disparate association with cardiovascular diseases. These differences need to be taken into consideration in everyday clinical practice.     

Use of combined oral contraceptives alters metabolic determinants and genetic regulation of C‐reactive protein. The Cardiovascular Risk in Young Finns Study

Background. Use of combined oral contraceptives (COCs) is known to increase concentrations of C‐reactive protein (CRP), an important predictor of cardiovascular disease. The inflammatory nature of the disease is well acknowledged. The aim of this study was to find out whether the metabolic, lifestyle and genetic determinants of CRP differ between women who use COCs and those who do not use any hormonal contraceptives (non‐users). Material and methods. A total of 1,257 women (24–39 years) participated in the ongoing Cardiovascular Risk in Young Finns Study, a population based cross‐sectional follow‐up study. Use of hormonal contraceptives was determined by questionnaire. Plasma CRP and other cardiovascular risk factors were measured; five CRP gene polymorphisms were genotyped (?717A>G, ?286C>T>A, +1059G>C, +1444C>T and +1846G>A) and CRP haplotypes were constructed. Results. Multivariate regression analysis revealed that BMI and leptin were the main determinants of CRP in non‐users, whereas in COC users the main determinants were BMI, leptin and triglycerides. The median CRP and triglyceride values were significantly higher in COC users than in non‐users. The correlations between triglyceride and CRP were tested separately in different COC users in accordance with progestagen content and dosage, the analysis revealing significant association only in women using a high dosage of progestagen or cyproterone. The haplotypes of CRP gene had no significant association with CRP concentration in COC users, while independent effects on CRP were found in non‐users. Conclusion. Our study suggests that use of COCs alters the metabolic determinants and genetic regulation of CRP.     

Vitamin D status and common risk factors for bone fragility as determinants of quantitative ultrasound variables in a nationally representative population sample

Calcaneal quantitative ultrasound (QUS) can predict bone strength and fracture risk. Bone fragility has no single cause but results from a complex interplay of several etiologic or contributing factors. Vitamin D is essential for bone health even though it is still unclear how much of this vitamin is required to maintain bone strength and prevent fractures. Measurements of serum 25-hydroxyvitamin D [S-25(OH)D] have indicated a high prevalence of inadequate vitamin D status in a number of studies mostly based on selected study populations. The objective of this study was to examine the associations between S-25(OH)D, common risk factors for bone fragility, and QUS variables in a large unselected population sample.The study population consisted of 2736 men and 3299 women from a nationally representative population sample, aged 30 years or over. Information on lifestyle was elicited by means of interviews and questionnaires. Body fat mass was estimated using an impedance-meter. S-25(OH)D was measured by radioimmunoassay. Calcaneal QUS was performed on the Hologic Sahara apparatus recording broadband ultrasound attenuation (BUA) and speed of sound (SOS). The potential determinants of BUA and SOS were analysed using separate multiple linear regression models for men and women.S-25(OH)D proved to be an independent determinant of BUA (P < 0.0001 for men, P < 0.001 for women) and SOS (P < 0.0001 for men, P < 0.05 for women). BUA was also independently associated with age, height, weight, alcohol consumption, and postmenopausal status in women, and with weight, alcohol consumption, smoking and physical activity in men. All of the above variables, except for weight in women, were also found to be independent determinants of SOS in both men and women. A reverse association was found between S-25(OH)D and adiposity in spite of higher intakes of vitamin D in those with higher fat mass.In this unselected sample of men and women, vitamin D status, several lifestyle factors and physical characteristics proved to be significant determinants of BUA and SOS. Inadequate vitamin D status was common, and measures ensuring adequate intakes of vitamin D in the population thus deserve continued attention. Obesity should be taken into account in future assessments of vitamin D status in Finland as in other countries.     

Long-term follow-up of methicillin-resistant Staphylococcus aureus molecular epidemiology after emergence of clone USA300 in San Francisco jail populations

We performed a longitudinal analysis of 502 unique methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates originating from San Francisco jail inmates between 2000 and 2007. Strain USA300, first encountered in 2001, accounted for 82.1% (412/502) of MRSA infections. Non-USA300 MRSA strains were rarely found after 2005 (one isolate in 2006, three in 2007).     

Beat-to-beat oscillations in pulse pressure

We compared 5-min standard deviations (SD) and frequency domain measures of beat-to-beat pulse pressure (PP) variability with those of RR-interval, systolic (SBP) and diastolic (DBP) blood pressure variabilities, and with cross-spectral baroreflex sensitivity (BRS) in a population-based sample of 150 healthy individuals, aged 35-64 years. Beat-to-beat variability of PP was composed of similar frequency components as the other spectral variabilities, and was closely related to SBP variability. The proportion of high frequency (HF) component from overall variability was higher in PP variability than in SBP and DBP variabilities. The low frequency (LF) component and the SD of beat-to-beat PP correlated inversely with BRS (-0.48 and -0.32, respectively; P<0.001 for both). To test a hypothesis that arterial stiffening is associated with increased beat-to-beat oscillation in PP, we examined associations of beat-to-beat PP variability with risk factors of atherosclerosis, i.e. with age, gender, smoking, blood pressure, body mass index, serum lipids, glucose, insulin and homeostasis model assessment of insulin resistance. The SD of beat-to-beat PP variability correlated with age (0.21, P = 0.010), PP (0.31, P<0.001) and body mass index (0.22, P = 0.008). The LF component of PP variability correlated not only with age (0.17, P = 0.041), PP (0.27, P = 0.001) and body mass index (0.22, P = 0.007), but also with serum insulin (0.17, P = 0.042), homeostasis model assessment of insulin resistance (0.18, P = 0.031) and serum triglycerides (0.16, P = 0.048). Our findings suggest that increased beat-to-beat oscillation of PP reflects arterial stiffening and impaired baroreflex function.