FinnGen provides genetic insights from a well-phenotyped isolated population

Population isolates such as those in Finland benefit genetic research because deleterious alleles are often concentrated on a small number of low-frequency variants (0.1% ≤ minor allele frequency < 5%). These variants survived the founding bottleneck rather than being distributed over a large number of ultrarare variants. Although this effect is well established in Mendelian genetics, its value in common disease genetics is less explored^1,2. FinnGen aims to study the genome and national health register data of 500,000 Finnish individuals. Given the relatively high median age of participants (63 years) and the substantial fraction of hospital-based recruitment, FinnGen is enriched for disease end points. Here we analyse data from 224,737 participants from FinnGen and study 15 diseases that have previously been investigated in large genome-wide association studies (GWASs). We also include meta-analyses of biobank data from Estonia and the United Kingdom. We identified 30 new associations, primarily low-frequency variants, enriched in the Finnish population. A GWAS of 1,932 diseases also identified 2,733 genome-wide significant associations (893 phenome-wide significant (PWS), P < 2.6 × 10^-11) at 2,496 (771 PWS) independent loci with 807 (247 PWS) end points. Among these, fine-mapping implicated 148 (73 PWS) coding variants associated with 83 (42 PWS) end points. Moreover, 91 (47 PWS) had an allele frequency of <5% in non-Finnish European individuals, of which 62 (32 PWS) were enriched by more than twofold in Finland. These findings demonstrate the power of bottlenecked populations to find entry points into the biology of common diseases through low-frequency, high impact variants.

CYP2C19 loss-of-function alleles and the use of omeprazole or esomeprazole increase the risk of cardiovascular outcomes in patients using clopidogrel – a real-world study

Background

Patients carrying loss-of-function (LOF) variants of CYP2C19 or using the CYP2C19-inhibitors omeprazole or esomeprazole cannot fully bioactivate clopidogrel, and thus are lacking optimal thrombosis prevention. However, clopidogrel is a relevant alternative to ticagrelor due to its lower incidence of hemorrhagic events and lower cost.

Purpose

The purpose of this study was to investigate in a real-life prospective patient cohort how loss-of-function (LOF) CYP2C19 variants and omeprazole or esomeprazole influence the incidence of cardiovascular events (cardiovascular deaths, reinfarction and strokes) in patients using clopidogrel.

Methods

A cohort of prospective patients (N=1972) with acute coronary syndrome (ACS) (N=1302) or symptomatic chronic coronary disease (N=670) were followed for 365 days. Information of purchased prescription drugs, hospital discharge, and death registry was available for all patients. The patients were retrospectively genotyped for the CYP2C19*2, CYP2C19*3, and CYP2C19*8 LOF variants.

Results

A total of 608 (30.8%) patients carried CYP2C19 LOF alleles. During the 365 days follow-up, 252 patients had a recurring ischemic vascular event, either myocardial infarction (N=189), stroke (N=24) or cardiovascular death (N=39). Vascular events were significantly more frequent among carriers of CYP2C19 LOF alleles [14.8% (95% CI 11.7–17.8] than in non-carriers [10.8% (95% CI 9.0–12.6)], p=0.016. Omeprazole or esomeprazole use was similar among the LOF allele carriers and non-carriers, but inclusion of their use in the analysis strengthened the association. Vascular events were significantly more common in a composite group of carriers of CYP2C19 LOF alleles and non-carriers who were using omeprazole or esomeprazole than in non-carriers who were not using omeprazole or esomeprazole 14.8% (95% CI 12.2–17.3) vs 9.9% (95% CI 8.0–11.9) p=0.002. There was a tendency towards lower risk of hemorrhagic complications in carriers of LOF alleles than in non-carriers (p=0.07).

Conclusions

Patients with impaired clopidogrel bioactivation due to loss-of-function CYP2C19 variants or concomitant omeprazole or esomeprazole use are at increased risk of cardiovascular events. For relevant patient care both genetics and concomitant medication should be considered both in everyday patient care and further randomised studies.

Funding Acknowledgement

Type of funding sources: None.

Use of antihypertensive medication before diagnosis of atrial fibrillation in Finland – results from the nationwide FinACAF -study

Background and aims

Long-standing arterial hypertension increases the risk of cardiovascular morbidity including atrial fibrillation (AF), coronary heart disease and renal failure. Arterial hypertension is the most common aetiologic factor associated with the development of AF and is also the most prevalent co-morbid cardiovascular disease in patients with AF. Coexisting arterial hypertension together with AF increases further the risk of stroke, heart failure and overall mortality.

The Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) -study is a nationwide retrospective register-based AF study that combines data from several Finnish health care registers. In this sub-study, we characterized the use of antihypertensive medications in patients with new-onset AF.

Methods

This sub-study included all adult new-onset AF patients of the FinACAF study from January 2007 to December 2018. Patients were excluded if they were under 18 years of age, had any oral anticoagulant purchase in the year prior to AF diagnosis, or had diagnosis of AF or warfarin purchases between the years 2004–2006.

Appropriate data such as anonymized study ID's, ICD-10 diagnoses, and drug purchases (dates, ATC-codes, amounts) were obtained from the National Prescription Register as well as the Finnish Hospital and Primary care registers. The antihypertensive medication purchases from the year preceding the AF diagnosis were analysed and identified by appropriate ATC-codes. Purchases one-month prior to the new-onset AF diagnosis were excluded from in order to avoid confounding by any medication changes due to AF diagnosis.

Results

Of 229,282 patients with new-onset AF 164,527 (71.8%) had purchased antihypertensive medication during the year prior to the AF diagnosis. The most common antihypertensive drugs used were beta blockers (n=108,510; 47.3%), ACE-inhibitors or angiotensin receptor blockers (n=104,840; 45.7%), diuretics (n=79,270; 34.6%) and selective calcium channel blockers (n=61,610; 26.9%). Diltiazem was purchased by 2,001 patients (0.9%) and verapamil by 1,508 patients (0.7%). At the beginning of the study period, beta-blockers were the most widely used antihypertensive agents, but between 2007 and 2018, RAAS-inhibitors (ACE inhibitors and ARB blockers) became the most widely used group of antihypertensive drugs (Figure 1).

Conclusion

Most Finnish new-onset AF patients had at least one pre-existing antihypertensive medication in use before the diagnosis of AF. Beta blockers were the most common antihypertensives until the latest years when RAAS-inhibitors became the most prescribed antihypertensive agents, whereas the use of diltiazem and verapamil was marginal in the treatment of hypertension before the AF diagnosis.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Helsinki and Uusimaa Hospital District research fundThe Finnish Foundation for Cardiovascular Research Figure 1. Annual use of antihypertensive medication among Finnish new-onset AF patients prior to diagnosis. Annual number of new-onset AF patients plotted for reference.

Early findings from periscope (Pan-European response to the impacts of COVID-19 and future pandemics and epidemics)

Abstract Body

The H2020/PERISCOPE project, including 32 partners from European universities & agencies, began 1st November 2020 and will last 36 months. The overarching objectives of PERISCOPE are to map and analyse the unintended impacts of the COVID-19 outbreak; develop solutions and guidance for policymakers and health authorities on how to mitigate the impact of the outbreak; enhance Europe’s preparedness for future similar events; and reflect on the future multi-level governance in the health as well as other domains affected by the outbreak. During this session we will report about early lessons learnt from the mapping and assessments of the impacts of the COVID-19 outbreak on mental health at national and subnational level in the EU with respect to individuals, communities and societies. Further, we will comment on their comparability. The aim is to explore differences between countries regarding the occurrence of mental ill health, and especially the impact on vulnerable groups, and how this is related to exposure to SARS-CoV-2, differences in policies over time, and effects on the economy. We will reflect on the short- and long-term consequences on mental health and health inequalities, report on the ongoing development of holistic policy guidelines for health authorities & other authorities, and from the analysis of multilevel governance, at local, regional and national level, memberstate – EU-level, and EU - global governance level. PERISCOPE will continue collecting data and updating a common data ”Atlas”, which would lead the consortium to engage in modelling and experiments to provide “continuous nowcasting” of the outbreak.

Disclosure

No significant relationships.

Completed suicides of citalopram users-the role of CYP genotypes and adverse drug interactions

Depression is known to be a risk factor for suicide. Currently, the most used antidepressants are selective serotonin reuptake inhibitors (SSRIs). Not all users, however, benefit from them. In such cases, treatment failure can be explained in part by genetic differences. In this study, we investigated the role of pharmacogenetic factors in citalopram-positive completed suicides (n = 349). Since citalopram is metabolized by CYP2C19 and CYP2D6 enzymes, the study population was genotyped for clinically relevant CYP2C19 and CYP2D6 polymorphisms and CYP2D6 copy number variation. To assess genetic differences between suicide cases and Finns in general, Finnish population samples (n = 855) were used as controls. Also, the role of drug interactions among suicide cases was evaluated. We found enrichment of a combined group of genetically predicted poor and ultrarapid metabolizer phenotypes (gMPs) of CYP2C19 among suicide victims compared to controls 0.356 [0.31-0.41] vs. 0.265 [0.24-0.30] (p = 0.0065). In CYP2D6 gMPs, there was no difference between cases and controls when the study population was analyzed as a whole. However, there were significantly more poor metabolizers among females who committed suicide by poisoning compared to female controls. In 8% of all drug poisoning deaths, lifetime drug-drug interaction was evaluated having a contribution to the fatal outcome. From clinical perspective, pharmacogenetic testing prior to initiation of SSRI drug could be beneficial. It may also be useful in medico-legal settings as it may elucidate obscure poisoning cases. Also, the possibility of unintentional drug interactions should be taken into account in drug poisoning deaths.

Temporal variation in coat colour (genotypes) supports major changes in the Nordic cattle population after Iron Age

Variation in coat colour genotypes of archaeological cattle samples from Finland was studied by sequencing 69 base pairs of the extension locus (melanocortin 1-receptor, MC1R) targeting both a transition and a deletion defining the three main alleles, such as dominant black (E(D) ), wild type (E(+) ) and recessive red (e). The 69-bp MC1R sequence was successfully analysed from 23 ancient (1000-1800 AD) samples. All three main alleles and genotype combinations were detected with allele frequencies of 0.26, 0.17 and 0.57 for E(D) , E(+) and e respectively. Recessive red and dominant black alleles were detected in both sexes. According to the best of our knowledge, this is the first ancient DNA study defining all three main MC1R alleles. Observed MC1R alleles are in agreement with calculated phenotype frequencies from historical sources. The division of ancient Finnish cattle population into modern Finnish breeds with settled colours was dated to the 20th century. From the existing genotyped populations in Europe (43 breeds, n = 2360), the closest match to ancient MC1R genotype frequencies was with the Norwegian native multicoloured breeds. In combined published genotype data of ancient (n = 147) and genotypes and phenotypes of modern Nordic cattle (n = 738), MC1R allele frequencies showed temporal changes similar to neutral mitochondrial DNA and Y-chromosomal haplotypes analysed earlier. All three markers indicate major change in genotypes in Nordic cattle from the Late Iron Age to the Medieval period followed by slower change through the historical periods until the present.

Ketamine coadministration attenuates morphine tolerance and leads to increased brain concentrations of both drugs in the rat

Background and Purpose

The effects of ketamine in attenuating morphine tolerance have been suggested to result from a pharmacodynamic interaction. We studied whether ketamine might increase brain morphine concentrations in acute coadministration, in morphine tolerance and morphine withdrawal.

Experimental Approach

Morphine minipumps (6 mg·day^–1) induced tolerance during 5 days in Sprague–Dawley rats, after which s.c. ketamine (10 mg·kg^–1) was administered. Tail flick, hot plate and rotarod tests were used for behavioural testing. Serum levels and whole tissue brain and liver concentrations of morphine, morphine-3-glucuronide, ketamine and norketamine were measured using HPLC-tandem mass spectrometry.

Key Results

In morphine-naïve rats, ketamine caused no antinociception whereas in morphine-tolerant rats there was significant antinociception (57% maximum possible effect in the tail flick test 90 min after administration) lasting up to 150 min. In the brain of morphine-tolerant ketamine-treated rats, the morphine, ketamine and norketamine concentrations were 2.1-, 1.4- and 3.4-fold, respectively, compared with the rats treated with morphine or ketamine only. In the liver of morphine-tolerant ketamine-treated rats, ketamine concentration was sixfold compared with morphine-naïve rats. After a 2 day morphine withdrawal period, smaller but parallel concentration changes were observed. In acute coadministration, ketamine increased the brain morphine concentration by 20%, but no increase in ketamine concentrations or increased antinociception was observed.

Conclusions and Implications

The ability of ketamine to induce antinociception in rats made tolerant to morphine may also be due to increased brain concentrations of morphine, ketamine and norketamine. The relevance of these findings needs to be assessed in humans.

Maternal and paternal genetic diversity of ancient sheep in Estonia from the Late Bronze Age to the post-medieval period and comparison with other regions in Eurasia

Sheep were among the first domesticated animals to appear in Estonia in the late Neolithic and became one of the most widespread livestock species in the region from the Late Bronze Age onwards. However, the origin and historical expansion of local sheep populations in Estonia remain poorly understood. Here, we analysed fragments of the hypervariable D-loop of mitochondrial DNA (mtDNA; 213 bp) and the Y-chromosome SRY gene (130 bp) extracted from 31 archaeological sheep bones dated from approximately 800 BC to 1700 AD. The ancient DNA data of sheep from Estonia were compared with ancient sheep from Finland as well as a set of contemporary sheep breeds from across Eurasia in order to place them in a wider phylogeographical context. The analysis shows that: (i) 24 successfully amplified and analysed mtDNA sequences of ancient sheep cluster into two haplogroups, A and B, of which B is predominant; (ii) four of the ancient mtDNA haplotypes are novel; (iii) higher mtDNA haplotype diversity occurred during the Middle Ages as compared to other periods, a fact concordant with the historical context of expanding international trade during the Middle Ages; (iv) the proportion of rarer haplotypes declined during the expansion of sheep from the Near Eastern domestication centre to the northern European region; (v) three male samples showed the presence of the characteristic northern European haplotype, SNP G-oY1 of the Y-chromosome, and represent the earliest occurrence of this haplotype. Our results provide the first insight into the genetic diversity and phylogeographical background of ancient sheep in Estonia and provide basis for further studies on the temporal fluctuations of ancient sheep populations.

Charge separation and charge recombination photophysical studies in a series of perylene–C60linear and cyclic dyads

A new donor–acceptor doubly bridged perylenediimide–fullerene dyad (PDI–C₆₀,DB-3), where the perylenediimide (PDI) acts as a donor, has been synthesized and studied by time-resolved absorption spectroscopy.

Temporal fluctuation in North East Baltic Sea region cattle population revealed by mitochondrial and Y-chromosomal DNA analyses

BACKGROUND

Ancient DNA analysis offers a way to detect changes in populations over time. To date, most studies of ancient cattle have focused on their domestication in prehistory, while only a limited number of studies have analysed later periods. Conversely, the genetic structure of modern cattle populations is well known given the undertaking of several molecular and population genetic studies.

RESULTS

Bones and teeth from ancient cattle populations from the North-East Baltic Sea region dated to the Prehistoric (Late Bronze and Iron Age, 5 samples), Medieval (14), and Post-Medieval (26) periods were investigated by sequencing 667 base pairs (bp) from the mitochondrial DNA (mtDNA) and 155 bp of intron 19 in the Y-chromosomal UTY gene. Comparison of maternal (mtDNA haplotypes) genetic diversity in ancient cattle (45 samples) with modern cattle populations in Europe and Asia (2094 samples) revealed 30 ancient mtDNA haplotypes, 24 of which were shared with modern breeds, while 6 were unique to the ancient samples. Of seven Y-chromosomal sequences determined from ancient samples, six were Y2 and one Y1 haplotype. Combined data including Swedish samples from the same periods (64 samples) was compared with the occurrence of Y-chromosomal haplotypes in modern cattle (1614 samples).

CONCLUSIONS

The diversity of haplogroups was highest in the Prehistoric samples, where many haplotypes were unique. The Medieval and Post-Medieval samples also show a high diversity with new haplotypes. Some of these haplotypes have become frequent in modern breeds in the Nordic Countries and North-Western Russia while other haplotypes have remained in only a few local breeds or seem to have been lost. A temporal shift in Y-chromosomal haplotypes from Y2 to Y1 was detected that corresponds with the appearance of new mtDNA haplotypes in the Medieval and Post-Medieval period. This suggests a replacement of the Prehistoric mtDNA and Y chromosomal haplotypes by new types of cattle.

Association between fluid balance and survival in critically ill patients

OBJECTIVE

Although the consequences of chronic fluid retention are well known, those of iatrogenic fluid retention that occurs during critical illness have not been fully determined. Therefore, we investigated the association between fluid balance and survival in a cohort of almost 16,000 individuals who survived an intensive care unit (ICU) stay in a large, urban, tertiary medical centre.

DESIGN

Longitudinal analysis of fluid balance at ICU discharge and 90-day post-ICU survival.

MEASUREMENTS

Associations between fluid balance during the ICU stay, determined from the electronic bedside record, and survival were tested using Cox proportional hazard models adjusted for severity of critical illness.

RESULTS

There were 1827 deaths in the first 90 days after ICU discharge. Compared with the lowest quartile of discharge fluid balance [median (interquartile range) -1.5 (-3.1, -0.7) L], the highest quartile [7.6 (5.7, 10.8) L] was associated with a 35% [95% confidence interval (CI) 1.13-1.61)] higher adjusted risk of death. Fluid balance was not associated with outcome amongst individuals without congestive heart failure or renal dysfunction. Amongst patients with either comorbidity, however, fluid balance was strongly associated with outcome, with the highest quartile having a 55% (95% CI 1.24-1.95) higher adjusted risk of death than the lowest quartile. Isotonic fluid balance, defined as the difference between intravenous isotonic fluid administration and urine output, was similarly associated with 90-day outcomes.

CONCLUSION

Positive fluid balance at the time of ICU discharge is associated with increased risk of death, after adjusting for markers of illness severity and chronic medical conditions, particularly in patients with underlying heart or kidney disease. Restoration of euvolaemia prior to discharge may improve survival after acute illness.

The clinical pharmacogenetics implementation consortium guideline for SLCO1B1 and simvastatin-induced myopathy: 2014 update

Simvastatin is among the most commonly used prescription medications for cholesterol reduction. A single coding single-nucleotide polymorphism, rs4149056T>C, in SLCO1B1 increases systemic exposure to simvastatin and the risk of muscle toxicity. We summarize evidence from the literature supporting this association and provide therapeutic recommendations for simvastatin based on SLCO1B1 genotype. This article is an update to the 2012 Clinical Pharmacogenetics Implementation Consortium guideline for SLCO1B1 and simvastatin-induced myopathy.

The mineralocorticoid receptor antagonist spironolactone enhances morphine antinociception

BACKGROUND

Spironolactone, a commonly used mineralocorticoid receptor antagonist, has been reported to potentiate the effect of morphine in the rat. The aim of this study was to investigate the effects of spironolactone on morphine antinociception and tissue distribution.

METHODS

The effects of spironolactone on acute morphine-induced antinociception, induction of morphine tolerance and established morphine tolerance were studied with tail-flick and hot plate tests in male Sprague-Dawley rats. Serum, brain, and liver morphine and its metabolite concentrations were quantified using high-pressure liquid chromatography-tandem mass spectrometry. Spironolactone was also administered with the peripherally acting, P-glycoprotein (P-gp) substrate loperamide to test whether spironolactone allows loperamide to pass the blood-brain barrier.

RESULTS

Spironolactone (50 mg/kg, i.p.) had no antinociceptive effects of its own, but it enhanced the antinociceptive effect of morphine in both thermal tests. Two doses of spironolactone enhanced the maximum possible effect (MPE) from 19.5% to 100% in the hot plate test 90 min after administration of 4 mg/kg morphine. Morphine concentrations in the brain were increased fourfold at 90 min by spironolactone. Spironolactone did not inhibit the formation of morphine-3-glucuronide. Acute spironolactone restored morphine antinociception in morphine-tolerant rats but did not inhibit the development of tolerance. The peripherally restricted opioid, loperamide (10 mg/kg), had no antinociceptive effects when administered alone, but co-administration with spironolactone produced a 40% MPE in the hot plate test.

CONCLUSIONS

Spironolactone has no antinociceptive effects in thermal models of pain, but it enhances the antinociceptive effects of morphine mainly by increasing morphine central nervous system concentrations, probably by inhibiting P-gp.

Mitochondrial DNA and Y-chromosomal diversity in ancient populations of domestic sheep (Ovis aries) in Finland: comparison with contemporary sheep breeds

Background

Several molecular and population genetic studies have focused on the native sheep breeds of Finland. In this work, we investigated their ancestral sheep populations from Iron Age, Medieval and Post-Medieval periods by sequencing a partial mitochondrial DNA D-loop and the 5’-promoter region of the SRY gene. We compared the maternal (mitochondrial DNA haplotypes) and paternal (SNP oY1) genetic diversity of ancient sheep in Finland with modern domestic sheep populations in Europe and Asia to study temporal changes in genetic variation and affinities between ancient and modern populations.

Results

A 523-bp mitochondrial DNA sequence was successfully amplified for 26 of 36 sheep ancient samples i.e. five, seven and 14 samples representative of Iron Age, Medieval and Post-Medieval sheep, respectively. Genetic diversity was analyzed within the cohorts. This ancient dataset was compared with present-day data consisting of 94 animals from 10 contemporary European breeds and with GenBank DNA sequence data to carry out a haplotype sharing analysis. Among the 18 ancient mitochondrial DNA haplotypes identified, 14 were present in the modern breeds. Ancient haplotypes were assigned to the highly divergent ovine haplogroups A and B, haplogroup B being the major lineage within the cohorts. Only two haplotypes were detected in the Iron Age samples, while the genetic diversity of the Medieval and Post-Medieval cohorts was higher. For three of the ancient DNA samples, Y-chromosome SRY gene sequences were amplified indicating that they originated from rams. The SRY gene of these three ancient ram samples contained SNP G-oY1, which is frequent in modern north-European sheep breeds.

Conclusions

Our study did not reveal any sign of major population replacement of native sheep in Finland since the Iron Age. Variations in the availability of archaeological remains may explain differences in genetic diversity estimates and patterns within the cohorts rather than demographic events that occurred in the past. Our ancient DNA results fit well with the genetic context of domestic sheep as determined by analyses of modern north-European sheep breeds.

A mechanistic, model-based approach to safety assessment in clinical development

Assessing the safety of pharmacotherapies is a primary goal of clinical trials in drug development. The low frequency of relevant side effects, however, often poses a significant challenge for risk assessment. Methodologies allowing robust extrapolation of safety statistics based on preclinical data and information from clinical trials with limited numbers of patients are hence needed to further improve safety and efficacy in the drug development process. Here, we present a generic systems pharmacology approach integrating prior physiological and pharmacological knowledge, preclinical data, and clinical trial results, which allows predicting adverse event rates related to drug exposure. Possible fields of application involve high-risk populations, novel drug candidates, and different dosing scenarios. As an example, the approach is applied to simvastatin and pravastatin and the prediction of myopathy rates in a population with a genotype leading to a significantly increased myopathy risk.CPT: Pharmacometrics & Systems Pharmacology (2012) 1, e13; doi:10.1038/psp.2012.14; advance online publication 7 November 2012.

The clinical pharmacogenomics implementation consortium: CPIC guideline for SLCO1B1 and simvastatin-induced myopathy

Cholesterol reduction from statin therapy has been one of the greatest public health successes in modern medicine. Simvastatin is among the most commonly used prescription medications. A non-synonymous coding single-nucleotide polymorphism (SNP), rs4149056, in SLCO1B1 markedly increases systemic exposure to simvastatin and the risk of muscle toxicity. This guideline explores the relationship between rs4149056 (c.521T>C, p.V174A) and clinical outcome for all statins. The strength of the evidence is high for myopathy with simvastatin. We limit our recommendations accordingly.

Trends in population attributable fraction of acute coronary syndrome and ischaemic stroke due to diabetes in Finland

AIMS/HYPOTHESIS

Cardiovascular disease (CVD) event rates are decreasing, but the prevalence of diabetes is increasing. The effect of these developments on the population attributable fraction (PAF) of CVD events due to diabetes is not known.

METHODS

We used country-wide healthcare registers to identify all persons aged 25-80 years treated for diabetes in Finland during 1992-2002. These data were further linked to the National Cardiovascular Disease Register to identify the first CVD events (acute coronary syndrome and ischaemic stroke) among the individuals with and without diabetes. We calculated the annual PAF of the first CVD events due to diabetes separately for men and women.

RESULTS

The number of men treated for diabetes each year almost doubled during the study period from 37,073 to 69,158 between 1992 and 2002. Among women, the number increased from 42,485 to 57,372. The annual number of first CVD events in the country declined among men with diabetes from 13,436 to 12,678 and among women with diabetes from 8,658 to 7,521 between 1992 and 2002. During the same period, the PAF due to diabetes of the first CVD events increased among men from 11.4% (95% CI 10.8, 12.0%) to 13.8% (95% CI 13.2, 14.5%) and decreased among women from 20.1% (95% CI 19.2, 21.0%) to 16.9% (95% CI 15.9, 17.8%). The trends in PAF were different between the sexes (p < 0.001 for the interaction year × sex).

CONCLUSIONS/INTERPRETATION

Despite the very large increase in the prevalence of diabetes, the PAF of the first CVD events due to diabetes decreased in women and increased only slightly in men.

Transporter pharmacogenetics and statin toxicity

Polymorphisms in transporter genes can have profound effects on statin pharmacokinetics. In particular, a common genetic variant of organic anion-transporting polypeptide 1B1 reduces the hepatic uptake of many statins, increasing the risk of statin-induced myopathy. Similarly, genetically impaired adenosine triphosphate (ATP)-binding cassette G2 transporter efflux activity results in a marked increase in systemic exposure to various statins. Importantly, the effects of these genetic polymorphisms differ depending on the specific statin that is used. This provides a rational basis for the individualization of lipid-lowering therapy.

Impact of OATP transporters on pharmacokinetics

Membrane transporters are now recognized as important determinants of the transmembrane passage of drugs. Organic anion transporting polypeptides (OATP) form a family of influx transporters expressed in various tissues important for pharmacokinetics. Of the 11 human OATP transporters, OATP1B1, OATP1B3 and OATP2B1 are expressed on the sinusoidal membrane of hepatocytes and can facilitate the liver uptake of their substrate drugs. OATP1A2 is expressed on the luminal membrane of small intestinal enterocytes and at the blood-brain barrier, potentially mediating drug transport at these sites. Several clinically used drugs have been identified as substrates of OATP transporters (e.g. many statins are substrates of OATP1B1). Some drugs may inhibit OATP transporters (e.g. cyclosporine) causing pharmacokinetic drug-drug interactions. Moreover, genetic variability in genes encoding OATP transporters can result in marked inter-individual differences in pharmacokinetics. For example, a single nucleotide polymorphism (c.521T > C, p.Val174Ala) in the SLCO1B1 gene encoding OATP1B1 decreases the ability of OATP1B1 to transport active simvastatin acid from portal circulation into the liver, resulting in markedly increased plasma concentrations of simvastatin acid and an enhanced risk of simvastatin-induced myopathy. SLCO1B1 polymorphism also affects the pharmacokinetics of many other, but not all (fluvastatin), statins and that of the antidiabetic drug repaglinide, the antihistamine fexofenadine and the endothelin A receptor antagonist atrasentan. This review compiles the current knowledge about the expression and function of human OATP transporters, their substrate and inhibitor specificities, as well as pharmacogenetics.

Acoustic and neurophysiologic observations related to lingual nerve impairment

The purpose of this study was to determine the acoustic effects of lingual nerve impairment on speech. Neurophysiologic examination and thermal quantitative sensory testing (QST) were carried out to determine if the profile, type or severity of sensory nerve impairment had effects on the degree of speech changes. The study group consisted of 5 women and 5 men with lingual nerve damage following an oral and maxillofacial surgery procedure. Time interval between the examination and the nerve damage ranged from 1 month to 20 years. Formants and fundamental frequency and duration of vowel sounds were analyzed. The patients underwent sensory tests, blink reflex and thermal QST of the lingual nerve area. The lingual nerve impairment had effects on the central acoustic features of vowel sounds. A relationship was observed between warm detection threshold values and the magnitude of second formant changes in men. It is concluded that lingual nerve impairment has gender-specific effects on speech. The variability in the acoustic changes of vowel sounds between different patients indicates individual compensatory manners of speech production following lingual nerve impairment.

Potassium channel KCNH2 K897T polymorphism and cardiac repolarization during exercise test: The Finnish Cardiovascular Study

OBJECTIVE

Cardiac repolarization is regulated, in part, by the KCNH2 gene, which encodes a rapidly activating component of the delayed rectifier potassium channel. The gene expresses a functional single nucleotide polymorphism, K897T, which changes the biophysical properties of the channel. The objective of this study was to evaluate whether this polymorphism influences two indices of repolarization--the QT interval and T-wave alternans (TWA)--during different phases of a physical exercise test.

MATERIAL AND METHODS

The cohort consisted of 1,975 patients undergoing an exercise test during which on-line electrocardiographic data were registered. Information on coronary risk factors and medication was recorded. The 2690A>C nucleotide variation in the KCNH2 gene corresponding to the K897T amino acid change was analysed after polymerase chain reaction with allele-specific TaqMan probes.

RESULTS

Among all subjects, the QTc intervals did not differ between the three genotype groups (p> or =0.31, RANOVA). Women with the CC genotype tended to have longer QT intervals during the exercise test, but the difference was statistically significant only at rest (p = 0.011, ANOVA). This difference was also detected when the analysis was adjusted for several factors influencing the QT interval. No statistically significant effects of the K897T polymorphism on TWA were observed among all subjects (p = 0.16, RANOVA), nor in men and women separately.

CONCLUSIONS

The K897T polymorphism of the KCNH2 gene may not be a major genetic determinant for the TWA, but the influence of the CC genotype on QT interval deserves further research among women.

Characterization of novel CYP2C8 haplotypes and their contribution to paclitaxel and repaglinide metabolism

Cytochrome P450 2C8 (CYP2C8) plays a major role in the metabolism of therapeutically important drugs which exhibit large interindividual differences in their pharmacokinetics. In order to evaluate any genetic influence on this variation, a CYP2C8 phenotype-genotype evaluation was carried out in Caucasians. Two novel CYP2C8 haplotypes, named B and C with frequencies of 24 and 22% in Caucasians, respectively, were identified and caused a significantly increased and reduced paclitaxel 6alpha-hydroxylation, respectively, as evident from analyses of 49 human liver samples. In healthy white subjects, CYP2C8*3 and the two novel haplotypes significantly influenced repaglinide pharmacokinetics in SLCO1B1c.521T/C heterozygous individuals: haplotype B was associated with reduced and haplotype C with increased repaglinide AUC (0-infinity). Functional studies suggested -271C>A (CYP2C8*1B) as a causative SNP in haplotype B. In conclusion, two novel common CYP2C8 haplotypes were identified and significantly associated with altered rate of CYP2C8-dependent drug metabolism in vitro and in vivo.

Different effects of SLCO1B1 polymorphism on the pharmacokinetics of atorvastatin and rosuvastatin

Thirty-two healthy volunteers with different SLCO1B1 genotypes ingested a 20 mg dose of atorvastatin and 10 mg dose of rosuvastatin with a washout period of 1 week. Subjects with the SLCO1B1 c.521CC genotype (n=4) had a 144% (P<0.001) or 61% (P=0.049) greater mean area under the plasma atorvastatin concentration-time curve from 0 to 48 h (AUC(0-48 h)) than those with the c.521TT (n=16) or c.521TC (n=12) genotype, respectively. The AUC(0-48 h) of 2-hydroxyatorvastatin was 100% greater in subjects with the c.521CC genotype than in those with the c.521TT genotype (P=0.018). Rosuvastatin AUC(0-48 h) and peak plasma concentration (Cmax) were 65% (P=0.002) and 79% (P=0.003) higher in subjects with the c.521CC genotype than in those with the c.521TT genotype. These results indicate that, unexpectedly, SLCO1B1 polymorphism has a larger effect on the AUC of atorvastatin than on the more hydrophilic rosuvastatin.

Effects of transitory lingual nerve impairment on speech: an acoustic study of sibilant sound /s/

By measuring spectral characteristics of the sibilant /s/ this study investigated whether the reduced orosensory feedback caused by lingual nerve impairment affects the acoustics and articulation of sibilants. A further goal was to examine speakers' capability to compensate for the deviant control of the delicate movements required for the proper production of /s/ by experimentally modifying the function of the tongue in a way that reduces the necessary somatosensory information in articulation. Five healthy men with no speech, language or hearing abnormalities were enrolled. They produced the sibilant /s/ in a variety of phonetic contexts in two sessions: first in normal conditions and then with local anaesthesia of the right lingual nerve. From the speech samples, the spectral characteristics of the sibilant sound (i.e. the centre of gravity, standard deviation, skewness and kurtosis) were analysed acoustically. The results showed that the reduced tactile sensation has effects on the tongue function resulting in individual and variable spectral alterations. The variation between different speakers indicates individual ability to compensate for the effects caused by the sensory dysfunction of the tongue. It seems, therefore, that the compensatory mechanisms for speech production are highly speaker-dependent.

The National Hospital Discharge Register Data on Lower Limb Amputations

AIM

To study if data on lower limb amputations and vascular operations in the National Hospital Discharge Register can be used for comparison of diabetes care between hospital districts.

METHODS

We identified diabetic persons from the National Hospital Discharge Register (1988-2002), the National Social Security Institute (since 1964) and pharmacies (since 1994). A search for lower limb amputations and vascular operations was made through the Hospital Discharge Register. An analysis of the correlation of the age and gender adjusted incidence of first major amputations and the age and gender adjusted incidence of first vascular operations for diabetics was made between 14 hospitals districts with the largest diabetic population.

RESULTS

A total of 308,447 diabetics were identified. There were 11,070 diabetics who had a lower extremity amputation and 9530 diabetics who had a vascular operation in Finland in 1988-2002. The annual number of first amputations decreased from 924 to 387 per 100,000 diabetics during the study period. There were up to three-fold differences in age and gender adjusted indexed numbers of first amputations between different hospital districts during the last follow-up period from year 2000 to 2002. There was a clear inverse correlation between the incidence of first major amputations and first vascular operations and particularly between incidence of first major amputations and infrapopliteal reconstructions.

CONCLUSION

The incidence of major amputation is declining in the diabetic population. This positive development can be explained by more active vascular operative treatment. Regional differences are wider than acceptable.