Hospital Outcomes in Patients Hospitalized for COVID-19 Pneumonia: The Effect of SARS-CoV-2 Vaccination and Vitamin D Status

SARS-CoV-2 vaccination promises to improve outcomes for patients with COVID-19 pneumonia (most notably those with advanced age and at high risk for severe disease). Here, we examine serum 25-Hydroxyvitamin D (25(OH)D) status and outcomes in both old (>70 years) and young vaccinated (n = 80) and unvaccinated (n = 91) subjects, who were hospitalized due to COVID-19 pneumonia in a single center (Connolly Hospital Dublin). Outcomes included ICU admission and mortality. Serum 25(OH)D levels were categorized as D30 (<30 nmol/L), D40 (30-49.99 nmol/L) and D50 (≥50 nmol/L). In multivariate analyses, D30 was independently associated with ICU admission (OR: 6.87 (95% CI: 1.13-41.85) (p = 0.036)) and mortality (OR: 24.81 (95% CI: 1.57-392.1) (p = 0.023)) in unvaccinated patients, even after adjustment for major confounders including age, sex, obesity and pre-existing diabetes mellitus. While mortality was consistently higher in all categories of patients over 70 years of age, the highest observed mortality rate of 50%, seen in patients over 70 years with a low vitamin D state (D30), appeared to be almost completely corrected by either vaccination, or having a higher vitamin D state, i.e., mortality was 14% for vaccinated patients over 70 years with D30 and 16% for unvaccinated patients over 70 years with a 25(OH)D level greater than 30 nmol/L. We observe that high mortality from COVID-19 pneumonia occurs in older patients, especially those who are unvaccinated or have a low vitamin D state. Recent vaccination or having a high vitamin D status are both associated with reduced mortality, although these effects do not fully mitigate the mortality risk associated with advanced age.

Vitamin D Status and Mortality from SARS CoV-2: A Prospective Study of Unvaccinated Caucasian Adults

COVID-19 and a low vitamin D state share common risk factors, which might explain why vitamin D deficiency has been linked with higher COVID-19 mortality. Moreover, measures of serum vitamin D may become lower during systemic inflammatory responses, further confounding the association via reverse causality. In this prospective study (recruited over 12 months), we examined whether the association between a low vitamin D state and in-hospital mortality due to SARS-CoV-2 pneumonia in unvaccinated subjects is explained by (i) the presence of shared risk factors (e.g., obesity, advanced age) or (ii) a reduction in serum 25(OH)D due to COVID-19 (i.e., reverse causality). In this cohort of 232 (mean age = 56 years) patients (all had SARS-CoV-2 diagnosed via PCR AND required supplemental oxygen therapy), we failed to find an association between serum vitamin D and levels of CRP, or other inflammatory markers. However, the hazard ratio for mortality for subjects over 70 years of age (13.2) and for subjects with a serum 25(OH)D level less than 30 nmol·L−1 (4.6) remained significantly elevated even after adjustment for gender, obesity and the presence of diabetes mellitus. Subjects <70 years and >70 years had significantly higher mortality with a serum 25(OH)D less than 30 nmol·L−1 (11.8% and 55%), than with a serum 25(OH)D greater than 30 nmol·L−1 (2.2% and 25%). Unvaccinated Caucasian adults with a low vitamin D state have higher mortality due to SARS CoV-2 pneumonia, which is not explained by confounders and is not closely linked with elevated serum CRP.

Haplotype of receptor for advanced glycation end products is associated with arterial stiffness in essential hypertension

Background

What causes us to age has been extensively explored. The receptor for AGEs (RAGE) expression is up-regulated in atherosclerotic plaques and its activation leads to oxidative stress, cytokine and adhesion molecule formation, activation of nuclear factor-κB and cell apoptosis. We hypothesized that genetic variation in the RAGE receptor may be associated with arterial stiffness.

Methods

309 untreated hypertensive subjects were tested for genotypes of –374T&gt;A and –429T&gt;C polymorphisms with polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP). Arterial stiffness was measured as pulse wave velocity (PWV), augmentation index (AIx) and central aortic blood pressure (BP). Data was analysed using JMP Version 13 (SAS for Windows).

Results

Both polymorphisms were in Hardy-Weinberg equilibrium. The –374A A allele carriers had significantly lower aortic systolic BP (143±2 vs. 154±1, p&lt;0.001) while –429C allele carriers had lower aortic systolic BP (151±1 vs. 157±2, p&lt;0.01) compared with T carriers. –429C allele carriers had lower PWV compared to 429TT individuals (8.86±1 vs. 10.70±2.5). –374A allele carriers had lower PWV compared to 374TT individuals (9.7±1.43 vs. 10.65±2.6). Subjects with the AC haplotype had the lowest and those with the TT haplotype the highest PWV and aortic BP than any of the other haplotypes containing one or more of the at-risk alleles.

Conclusions

The combined effect of the two genotypes was additive with AA homozygotes of –374T&gt;A and C allele carriers of –429T&gt;C and the haplotype AC, associated with lowest aortic BP and arterial stiffness.

PWV & RAGE haplotypes

Funding Acknowledgement

Type of funding source: None

Regional variation in prescribing for chronic conditions among an elderly population using a pharmacy claims database

BACKGROUND

Age, gender and geographical regions are recognised factors in inequalities in prescribing for chronic diseases in the elderly.

AIM

To compare the health board regional distribution of chronic disease among the elderly and to examine variation in quality prescribing across age, gender and regions.

METHODS

Population based study of prescribing for chronic disease using a national pharmacy claims database. All individuals aged 70 years and over (n = 271,518) were eligible.

RESULTS

Over 60% of the elderly in all regions received cardiovascular related medication. The South Eastern, North Western and Western Health Boards had below average prescribing for many chronic conditions. Logistic regression identified age, gender and regional variations in prescribing of preventative therapies for CVD and diabetes.

CONCLUSION

There is a high prevalence of prescribing for chronic conditions in the elderly in Ireland, and there is evidence of gender, age and residing health board inequalities in prescribing.

Anti-depressants in primary care: analysis of treatment discontinuations

It is well known that adherence to anti-depressant therapy is often poor, but the literature describes little in the way of systematic analyses to determine co-relation between treatment discontinuation and possible contributing factors. We used a community dispensing database to review anti-depressant prescribing patterns and continuity of therapy over a period of 10 months among a population of community-based general practice patients. Some 109,228 anti-depressant prescriptions were dispensed to 24,073 patients, of whom 37.5% collected a single prescription only. Tricyclic anti-depressant prescribing declined significantly during the observation period (from 70% of prescriptions in month 1 to 66% in month 10) while that of selective serotonin reuptake inhibitors (SSRIs) increased (23% in month 1, 28% in month 10) ( p < 0.0001). Some 27% of those on tricyclics were prescribed <50% of the defined daily dose (DDD) compared with 2% of those on SSRIs. Among patients new to therapy who collected >1 prescription, adherence was poor and declined over time. The factors that influenced the extent to which patients failed to adhere to therapy included dosage level (% DDD) and age ( p <0.0001 for both), but not drug class or sex. The findings suggest that low dosage is a contributory factor in treatment discontinuation, and that contrary to common perception, SSRIs are not necessarily associated with better adherence to therapy than tricyclics. Copyright (c) 2000 John Wiley & Sons, Ltd.

A survey of patients' attitudes to clinical research

Every year hundreds of patients voluntarily participate in clinical trials across Ireland. However, little research has been done as to how patients find the experience. This survey was conducted in an attempt to ascertain clinical trial participants' views on their experience of participating in a clinical trial and to see and how clinical trial participation can be improved. One hundred and sixty-six clinical trial participants who had recently completed a global phase IV cardiovascular endpoint clinical trial were sent a 3-page questionnaire. Ninety-one (91%) respondents found the experience of participating in a clinical trial a good one with 85 (84.16%) respondents saying they would recommend participating in a clinical trial to a friend or relative and eighty-five (87.63%) respondents feeling they received better healthcare because they had participated in a clinical trial.

Prevalence of dyslipidaemia in statin-treated patients in Ireland: Irish results of the DYSlipidaemia International Study (DYSIS)

BACKGROUND

Statins are proven to reduce cardiovascular risk; however, substantial risk remains in patients on statin therapy. Persisting dyslipidaemia is likely to play a contributory role.

AIM

To assess the prevalence of persisting lipid abnormalities in patients treated with statins.

METHODS

DYSIS was a cross-sectional study of 22,063 patients in Europe and Canada. 900 Irish patients participated. All patients were ≥ 45 years and treated with statins for ≥ 3 months. Data were collected from the patients' records. ESC guidelines were used to classify risk and to define lipid levels.

RESULTS

Mean age was 66.1 years with women representing 40.7%. 78.6% were high-risk patients; that is 53.9% with cardiovascular disease (CVD), 20.1% with diabetes and 15.9% with a SCORE risk ≥ 5%. Total cholesterol was not at goal in 34.4% of all patients. LDL-C was elevated in 30.8% of all patients and in 30% at high risk. Low HDL-C was found in 34.7% of high-risk patients compared to 16.9% of patients with an ESC score <5%. In diabetics without CVD, low HDL-C and elevated TGs were found in 46 and 44.3%, respectively.

CONCLUSIONS

Despite statin therapy, a significant number of patients have persistent dyslipidaemia. While LDL-C targets are suboptimal in three out of ten patients, the prevalence of low HDL-C and high TGs in high-risk patients is greater than one in three. A more integrated approach to the treatment of patients with dyslipidaemia is warranted. Clinical trials are needed to assess the impact of therapies that raise HDL-C and lower elevated TGs.

Ventricular activation time as a marker for diastolic dysfunction in early hypertension

BACKGROUND

A standard 12-lead electrocardiogram (ECG) is performed in all hypertensive patients, primarily to detect left ventricular hypertrophy. Echocardiographic assessment of hypertensive subjects reveals that abnormalities in diastolic function occur more commonly and earlier than increased left ventricular mass. However, ECG changes associated with diastolic dysfunction (DD) remain poorly defined; we assessed the ventricular activation time (VAT) (i.e., the time for the ventricle to depolarize) as a potential marker for DD in early hypertension.

METHODS

Ninety subjects (aged 46 +/- 1.3 years; 43 men) with newly diagnosed, untreated hypertension underwent ECG and comprehensive two-dimensional echocardiography. Left ventricular DD was echocardiographically assessed using Canadian Consensus Guidelines. We compared VAT, which corresponds to the QR interval in the 12-lead ECG, with echocardiographic parameters of DD.

RESULTS

VAT was prolonged in subjects with DD (46.3 +/- 0.4 vs. 39.6 +/- 0.3 ms, P < 0.01). There was a significant correlation between VAT and tissue Doppler imaging (TDI) (early diastolic velocity) e' (r = -0.53, P < 0.0001), (ratio of early and late diastolic velocities) e'/a' (r = -0.53, P < 0.0001), transmitral Doppler (TMD) (early peak filling rate, and early deceleration peak) E/A (r = -0.32, P = 0.001), and (ratio of early diastolic mitral inflow and early diastolic velocities) E/e' (r = 0.44, P < 0.0001).

CONCLUSION

Prolongation of the VAT is associated with DD in patients with newly diagnosed untreated hypertension.

Blood pressure control determines improvement in diastolic dysfunction in early hypertension

BACKGROUND

Diastolic dysfunction is common in early hypertension. We hypothesized that improvement in diastolic dysfunction is blood pressure (BP) dependent and may occur early with treatment in newly diagnosed untreated hypertensive patients.

METHODS

Forty untreated hypertensive subjects (age 52 +/- 1.4 years, mean +/- s.e.m.) with diastolic dysfunction based on Canadian Consensus Guidelines, received either bendroflumethiazide 2.5 mg (1.25 mg for the first month), or candesartan 16 mg (8 mg for the first month). Left ventricular (LV) structure and function, early diastolic velocity (E') and systolic velocity, and systolic myocardial velocity (Sm) were assessed echocardiographically using M-mode, 2-dimensional, and tissue Doppler imaging (TDI) before and at 1 and 3 months following treatment.

RESULTS

Antihypertensive treatment reduced BP significantly at 3 months (168 +/- 2/97 +/- 1-143 +/- 2/86 +/- 1 mm Hg, P < 0.0001). Both drugs had similar and significant effects on TDI E' which increased from 7.8 +/- 0.2 to 10 +/- 0.3 cm/s (P < 0.001). The improvement in TDI E' was independent of LV mass index (LVMI) regression but was significantly related to the improvement in Sm (r = 0.73, P < 0.0001) and the fall in systolic BP (R = 0.51, P < 0.001). Normalization of diastolic function was associated with better control of BP (130 +/- 4/81 +/- 2 mm Hg vs. 149 +/- 2/88 +/- 1 mm Hg, P < 0.05). In a stepwise regression model, reduction in systolic BP (P < 0.001) and TDI Sm (P < 0.0001) emerged as independent determinants of improvement in TDI E' with no contribution from age, gender or change in relative wall thickness (RWT) (R(2) = 0.68, P < 0.0001).

CONCLUSIONS

Achieving good BP control and enhancement in systolic function determines the improvement in diastolic function in early hypertension.

EUROASPIRE (European Action on Secondary Prevention through Intervention to Reduce Events) III--a comparison of Irish and European results

The EUROASPIRE III audit was a Europe-wide study which took place in 2006/2007. The objective was to examine the control of risk factors in subjects with established cardiovascular disease. Here, we compare the Irish results to those of the other 21 European countries which participated. Control of blood cholesterol was significantly better in Irish participants, with 73% below the target of 4.5 mmol/l. Blood pressure control was less satisfactory in both Irish and European individuals, with an average of 52% of Irish participants not achieving blood pressure targets. Medication usage was high throughout, particularly anti-platelet agents, beta-blockers and, especially in Ireland, statins. Obesity figures were particularly high in Ireland and throughout Europe, with 82% Irish men and women either overweight or obese. Smoking figures in Irish women were also of concern, with 24% continuing to smoke. Cardiac rehabilitation attendance was particularly high in Ireland, with 68% attending; substantially higher than the European figure of 34%. In common with the rest of Europe, current control of body weight and blood pressure in Ireland is unsatisfactory and in need of increased consideration on the part of both patients and healthcare professionals.

Significant psychological morbidity occurs in irritable bowel syndrome: a case-control study using a pharmacy reimbursement database

BACKGROUND

Psychological problems are associated with IBS but the strength of this association is unclear.

AIM

To assess co-prescribing of antispasmodic and CNS-acting drugs through a nested case-control study.

METHODS

A national dispensing database identified patients who were first dispensed antispasmodic medicines for a continuous 3-month period or more during 2006, using 2005 as a run-in period. Each patient was matched with four control patients and excluded if they received drugs indicated for IBD.

RESULTS

Four hundred and seven patients commenced antispasmodic drugs during 2006. These patients were matched with 1628 controls. In 2005, patients subsequently prescribed antispasmodics were 2-3 times more likely to receive CNS-acting drugs than controls. In the year following commencement of IBS therapy, patients were 2-4 times more likely than controls to be prescribed CNS-acting drugs including antidepressants (35.4% vs. 9.3%), anxiolytics (27.8% vs. 8.8%), antipsychotics (9.8% vs. 3.3%) and hypno-sedatives (32.7% vs. 11.3%; P < 0.0001). The adjusted OR (95% CI) for antidepressant, anxiolytic, hypnosedative and antipsychotic prescribing in IBS patients were 3.81 (2.79-5.20), 2.84 (2.12-3.81), 2.62 (1.91-3.60) and 2.58 (1.80-3.66), respectively.

CONCLUSIONS

Patients prescribed ongoing therapy for presumed IBS are 2-4 times more likely to be prescribed CNS-acting drugs than controls, providing evidence of psychological comorbidity in IBS.

Epidemiology and economics of statin use

In 2006 the State supported the purchase of statins by some Euro 120 million for some 466,366 patients. While about 50% is for secondary prevention of heart disease a disproportionate number of women are receiving treatment for primary prevention. For proprietary agents the monthly cost was largely explained by price and dosage (mg/day) and the average varied from Euro 29.2 for rosuvastatin (11 mg), Euro 38.2 simvastatin (21 mg), Euro 39.1 atorvastatin (19 mg), Euro 42.7 pravastatin (21 mg) and Euro 31.8 for generic prava/simvastatin (21 mg). Generic substitution for pravastatin and simvastatin would save Euro 6.4m. Applying the drug prices corresponding in the United Kingdom would result in savings of some Euro 35m per annum. While the increasing use of statins is justified on cost benefit/analysis considerable savings could be made through choice of the more potent statins, a greater use of generics and a flatter dose price structure.

Adherence to clinical guidance in the prescribing of oral antithrombotic medication in patients with atrial fibrillation

BACKGROUND

Atrial fibrillation is the commonest cardiac rhythm disturbance and is an independent risk factor for stroke; however, use of oral antithrombotic therapy is reported to be suboptimal in clinical practice.

AIM

The aim of the study was to evaluate the prescribing rates of oral antithrombotic therapy in patients with atrial fibrillation to determine if prescribing patterns reflected published clinical guidance.

METHOD

Patients with atrial fibrillation, admitted to hospital over a 12-week period were identified and their antithrombotic therapy regimen was analysed using statistical methods.

RESULTS

Although 87/100 patients identified were prescribed OAT, the regimen was suboptimal in 35 patients. Patients aged 75 years and older were more likelyto be receiving suboptimal oral antithrombotic treatment compared with younger patients

CONCLUSIONS

The benefits and suitability of oral antithrombotic therapy for patients of all ages need to be more comprehensively communicated to prescribers.

Matrix metalloproteinase-9 polymorphism contributes to blood pressure and arterial stiffness in essential hypertension

Arterial stiffness is an independent predictor of cardiovascular events in a hypertensive population. Serum levels of matrix metalloproteinase (MMP)-9 are associated with arterial stiffness and predict cardiovascular risk. We investigated the role of MMP-9 polymorphism -1562C>T on blood pressure (BP) and arterial stiffness in a newly diagnosed hypertensive population. Untreated hypertensive patients (n=215, mean age 46+/-13 years) were studied. Supine BP, carotid-femoral pulse wave velocity (PWV) and augmentation index were assessed. Serum biochemistry and plasma MMP-9 concentrations were measured and genotyping performed following extraction of genomic DNA. BP, aortic PWV and serum MMP-9 levels were significantly higher in T-allele carriers of the -1562C>T polymorphism with a significant gene-dose effect (P<0.0001). In a stepwise regression model adjusting for known or likely determinants, the 1562C>T polymorphism emerged as an independent predictor of systolic BP (R(2)=0.25, P<0.0001), diastolic BP (R(2)=0.16, P<0.0001) and PWV (R(2)=0.47,P<0.0001). This is the first study to show the effect of MMP-9 polymorphism on BP and aortic stiffness in a hypertensive population. These results suggest that hypertensive patients carrying the T allele may be at increased risk of cardiovascular events.

Impact of the ATAC trial on prescribing of hormonal therapy in breast cancer

11028

Background: The arimidex, tamoxifen, alone or in combination (ATAC) trial recommended use of anastrazole over tamoxifen as initial adjuvant hormonal therapy of early breast cancer in postmenopausal women. The aim of this study was to investigate the impact of the publication of the ATAC trial in December 2004 on subsequent prescribing of hormonal therapy to Irish women =55 years old. Methods: The Irish HSE-PCRS pharmacy claims database was used to identify all women =55 years old, commenced on tamoxifen or an aromatase inhibitor as initial hormonal therapy, between July 2000 and June 2006. A segmented regression analysis of an interrupted time series was used to detect changes in the trend and level of anastrazole prescribing after publication of the ATAC trial in December 2004 and the prior updates in November 2003 and June 2002 (presented December 2001). β coefficients and 95%CI are presented where appropriate. The absolute change in anastrazole prescribing and 95%CI are also calculated for selected months. Statistical analysis was performed using SAS version 9.1. Significance at p<0.05 is assumed. Results: A cohort of 7,604 women =55 years old, commenced on initial hormonal therapy, was identified from the HSE-PCRS database, 2,206 (29%) of these women were prescribed anastrazole. In the month following publication of the final results of the ATAC trial there was a 17.6% (95% CI 10.8%, 24.5%) absolute increase in anastrazole prescribing. This represented a statistically significant increase in the level of prescribing (level change β=18.1 95% CI 11.3, 24.9 p<0.0001). There was also a significant change in anastrazole prescribing trend after presentation of the first ATAC update (slope change β=0.98 95% CI 0.59, 1.37 p<0.0001). Conclusion: The publication of the final ATAC trial data resulted in a significant increase in the prescribing of anastrazole. This is objective evidence that oncologists respond rapidly to clinical trial results. It is unclear whether the significant increase in anastrazole prescribing after the first ATAC update is an appropriate response to an interim analysis.

No significant financial relationships to disclose.

Acute haemodynamic effects of cigarette smoking in healthy young subjects

BACKGROUND

Invasive studies in middle-aged patients suggest an acute adverse haemodynamic effect of smoking.

AIMS

To study acute changes in blood pressure (BP), cardiac output, peripheral resistance and aortic compliance following cigarette smoking in healthy young subjects.

METHODS

Using a non-invasive photoplethysmographic technique we compared the effects of smoking one cigarette with sham smoking in 12 healthy volunteers (22-25 years). Data was analysed using JMP version 5.0.

RESULTS

In contrast to sham smoking there was a prompt increase in blood pressure with a maximum effect at 15 min (123 +/- 7/75 +/- 5 to 143 +/- 6/86 +/- 6 mmHg, mean +/- SEM, p < 0.01) which is attributed to a rise in cardiac output (p < 0.05) rather than changes in peripheral vascular resistance. There was also a significant (p < 0.05) increase in heart rate and a reduction in aortic compliance.

CONCLUSION

These results suggest that healthor young age do not protect from the adverse effects of smoking.

An evaluation of the effects of renal artery stenting in renovascular hypertension

Renal artery stenosis is a common cause (1-6%) of secondary hypertension. Renal artery stenting has recently been employed as an adjunct to antihypertensive medication. We evaluated 92 patients who underwent renal angiography of whom 30 were stented. There was a reduction (p < 0.01) in blood pressure immediately post renal artery stenting--systolic BP from 157 +/- 20 to 140 +/- 21 mmHg and diastolic BP from 81 +/- 13 to 72 +/- 12 mmHg was sustained at 6 months follow up (148 +/- 20/76 +/- 12 mmHg) in the outpatients' clinic. The amount of antihypertensive medication did not differ post stenting--2.7 +/- 1.2 pre vs 2.7 +/- 1.2 drugs post procedure. Renal artery stenting did not provide a 'cure' for any patient with atherosclerotic renovascular hypertension and until the results of randomized studies are known we believe use should be restricted.

An HPLC method for the determination of the free cortisol/cortisone ratio in human urine

The measurement of the urinary free cortisol-cortisone ratio has been reported to be a sensitive indicator of renal 11 beta-hydroxysteroid dehydrogenase type 2 (11 beta-HSD 2) activity. This converts biologically active cortisol to inactive cortisone. A decrease in its activity (e.g. through disease or inhibition caused by a therapeutic agent or a foodstuff) may increase cortisol levels and susceptibility towards hypertension. The method presented here uses a simple isocratic tandem column HPLC system. The method has been validated and found to be robust and reproducible. The lower limit of quantification (LLOQ) was found to be 10 ng/mL for both cortisol and cortisone. Samples of urine (n = 99) from patients, most of whom were on complex combinations of drugs, were analyzed and 92% of samples were found to give successful results with this method (cortisol and cortisone above LLOQ). The ratio ranged from 0.07 to 5.61. No interferences were noted from the drugs that the patients were taking. It was also found that a morning spot urine sample gave comparable results to 24 h collection samples, thus making sample collection much easier.

Impact of Helicobacter pylori on the management of dyspepsia in primary care

BACKGROUND

It is unclear what impact Helicobacter pylori infection has had on the management of dyspepsia in primary care and to what extent published guidelines on H. pylori are implemented in routine clinical practice.

AIM

To assess the impact of H. pylori infection on the management of dyspepsia in primary care.

METHODS

Patients referred by primary care doctors to an open-access 13-carbon urea breath test service over a 2-year period for their first urea breath test were included in the study. Individual breath results were linked with data on prescribing obtained from the General Medical Services prescription database.

RESULTS

Of 805 patients, 374 (47%) had a positive urea breath test and 431 (54%) a negative urea breath test. Of positive urea breath test patients, only 245 (64%) were prescribed eradication therapy in the 3 months after the breath test and only 43% were referred back for re-testing. In the year after the urea breath test, there was a significant fall in prescribing of antisecretory therapy which was greatest in the patients who received H. pylori therapy (P < 0.001).

CONCLUSIONS

There appears to be under and inappropriate treatment of H. pylori infection in primary care, and a low rate of re-testing after eradication, indicating that current guidelines are not well implemented in practice.

The population mortality benefits of maximizing the number of eligible patients receiving appropriate cardiology treatments in Ireland

BACKGROUND

Coronary heart disease (CHD) mortality rates have been decreasing in many industrialized countries since the 1980s. Up to half this decrease can be attributed to evidence-based medical and surgical cardiology interventions. However, recent studies suggest that modern cardiology treatment uptake levels remain disappointingly low in many patient categories.

AIM

To determine the potential for further reductions in CHD mortality in Ireland from increasing the number of eligible patients receiving cardiology treatments.

METHODS

A previously validated, cell-based IMPACT CHD mortality model was used to integrate large amounts of data describing CHD patient numbers, and the effectiveness and uptake levels of specific medical and surgical treatments. The CHD mortality reductions potentially achievable through the increased use of specific treatments were then calculated, stratified by age and gender and tested using sensitivity analyses.

RESULTS

In 2000, medical and surgical coronary disease treatments together prevented or postponed approximately 1950 CHD deaths in the adult population aged 25-84. However, increasing treatment levels to reach 80% of eligible patients might have prevented or postponed a further 2280 CHD deaths in 2000 (minimum estimate 860, maximum estimate 4000). The biggest gain was from maximizing the treatment uptake of eligible heart failure patients, followed by those receiving statins and secondary prevention therapies.

DISCUSSION

Many eligible patients are currently not receiving appropriate evidence-based treatments that would reduce CHD mortality and morbidity. Our results suggest that increasing cardiology treatment uptake in Ireland could at least double the current therapeutic reduction in CHD mortality.

Prescribing for patients with diabetes in the community drug schemes

The aim of the study was to examine the management of diabetes patients particularly in relation to secondary preventative therapies within the community drug schemes across the health board regions in Ireland. The study population was identified using two national primary care prescribing databases from the Long Term Illness (LTI) and General Medical Services (GMS) scheme for 2003. 65,593 patients were identified as having 'treated' diabetes. Logistic regression was used to predict the likelihood of receiving secondary preventative therapies by region and drug scheme using adjusted odds ratios (ORs) and 95% confidence intervals (CI). The proportion of diabetes patients in each drug scheme with Ischaemic Heart Disease (IHD) was also calculated. Prevalence of 'treated' diabetes was calculated for each health board also. Regional and scheme-based variations within each region exist in the prescribing of secondary preventative therapies after adjustment for IHD rates. Prevalence of treated diabetes varied between regions from 1.5% in the Eastern region to 2.2% in the Southern region. While the location of specialised diabetes clinics may be a contributing factor, inequalities in prescribing across regions within the drug schemes are apparent.

Collagen type-I degradation is related to arterial stiffness in hypertensive and normotensive subjects

Although arterial stiffness is an independent cardiovascular risk factor associated with both aging and hypertension, relatively little is known regarding the structural changes in the vessel wall that occur with vessel stiffening. We determined if collagen type-I metabolism is related to arterial stiffening in both hypertensive and normotensive subjects. Arterial stiffness was assessed by aortic pulse wave velocity (PWV) and augmentation index (AIx) in 46 subjects (48.7 +/- 2 years, 32 hypertensives) and related to circulating markers of collagen type-I turnover. Collagen synthesis was assessed by the measurement of carboxy-terminal peptide of procollagen type-I (PIP) and collagen degradation by the measurement of carboxy-terminal telopeptide of collagen type-I (ICTP), by quantitative immunoassay. Matrix metalloproteinase-1 (MMP-1) and the tissue inhibitor of metalloproteinase-1 (TIMP-1) were also quantified by immunoassay. The ratio of collagen type-I synthesis to degradation was negatively correlated with both PWV (P<0.05) and AIx (P<0.05), whereas plasma MMP-1 levels displayed a positive correlation with both PWV (P<0.01) and AIx (P<0.01), after adjustment for age and mean arterial pressure. The relationship between collagen type-I turnover and arterial stiffness was similar in both the normotensive and hypertensive subjects. Although circulating markers of collagen synthesis were increased in the hypertensive subjects, this was not related to arterial stiffness. Collagen type-I degradation is increased in relation to collagen type-I synthesis in subjects with stiffer arteries. Matrix metalloproteinase-1, the enzyme responsible for collagen type-I degradation, is positively related to both large elastic and muscular artery stiffness in normotensive and hypertensive subjects.

Effect of clinical trial publicity on HRT prescribing in Ireland

OBJECTIVE

To evaluate the effect of publicity surrounding the Women's Health Initiative (WHI) and Million Women (MW) studies on prescribing of all hormone replacement therapy (HRT) preparations and bisphosphonates in Ireland.

METHODS

The General Medical Services (GMS) prescription database was used to identify the study population. Prescriptions were identified for HRT and bisphosphonate preparations [using WHO Anatomical Therapeutic Chemical (ATC) classification codes] in female patients aged 45-69 years in Ireland during a 4-year study period (January 2001-December 2004). Prescription rates were calculated monthly. Prevalence and incidence of HRT use was examined.

RESULTS

There was a significant reduction in prevalence for all HRT preparations following the WHI trial (test for change in trend p<0.0001), which persisted after the MW study. The incidence of combined oestrogen/progestogen HRT declined after the WHI trial (test for change in trend p=0.004). Bisphosphonate prescribing showed a significant increase throughout the study period (p<0.0001).

CONCLUSION

The findings suggest that coverage surrounding the publication of clinical trials appears to have had a negative impact on the rate of HRT prescribing. The findings regarding the coincident increase in use of bisphosphonates may suggest that prescribers and users were less likely to regard HRT as an appropriate therapy in the management of osteoporosis for some time before guidance was issued by the regulatory authorities.

Socioeconomic influences on benzodiazepine consumption in an Irish Region

Misuse of prescription sedatives is a significant problem for addiction treatment services. The aim of this study was to examine the prescribing of diazepam in disadvantaged Irish communities, and to identify factors which may predict diazepam consumption in that population. We examined prescribing trends for those aged 16-69 years in 2002 in a region of the state-funded General Medical Services Scheme. Material deprivation was based on the 2002 Small Area Health Research Unit (SAHRU) deprivation index. The average defined daily dose (DDD) was calculated and logistic regression analysis was used to predict diazepam use by age, gender and deprivation index. Results showed that patients living in the most-deprived areas were more likely to receive diazepam than patients living in the least-deprived areas (OR = 1.21, 95% CI 1.15-1.27). Female patients living in the most-deprived areas were also more likely to receive diazepam than those living in the least-deprived areas (OR = 1.36, 95% CI 1.18-1.57). It is concluded that there is a pattern of higher diazepam prescribing in areas of greatest deprivation, where prescription sedatives play a complex role within troubled families.

Changes in prevalence of and prescribing for Ischaemic heart disease in Ireland 1990–2002

BACKGROUND

Secondary prevention therapies, such as angiotension converting enzyme (ACE) inhibitors, beta-blockers and statins, are known to reduce cardiovascular morbidity and mortality.

OBJECTIVE

The aim of the study was to examine the prevalence of coronary heart disease (CHD) and the prescribing of secondary preventive therapies in the period 1990-2002.

METHODS

The General Medical Services prescription database was used to identify the study cohort, those with CHD, in each year 1990-2002. CHD was defined in two ways: prescription of any nitrate, and co-prescription of nitrate and aspirin. In addition, co-prescription of secondary preventive agents including statins, ACE inhibitors and beta blockers were examined.

RESULTS

We found a significant increasing prevalence of CHD from 1990 to 2002 in both men and women. There was a significant increase (p < 0.0001) in the prescribing rate for beta blockers, ACE inhibitors, and for statins, buta significant decrease (p < 0.0001) for calcium channel blockers.

CONCLUSION

These trends reflect the growing evidence base on the effectiveness of secondary preventive therapies, and the implementation of the National Cardiovascular Health Strategy.

The application of prescribing indicators to a primary care prescription database in Ireland

OBJECTIVE

To develop appropriate prescribing indicators and apply these to Irish prescription data.

METHODS

A postal survey of 145 randomly selected general practitioners working within the Eastern Health Board region of the State-supported General Medical Services scheme in Ireland regarding the applicability of selected prescribing indicators was carried out. Such indicators were then applied to aggregate prescription data.

RESULTS

Prescribing indicators based on agents of questionable efficacy/poor quality prescribing and those based on good prescribing practice were thought to make suitable indicators. Low rates of prescribing were noted for indicators based on drugs of limited efficacy, e.g. cerebral and peripheral vasodilators (rate 3.1 per 1,000 prescriptions), whilst indicators based on drugs associated with good prescribing practice were associated with higher prescribing rates, e.g. the prescription of aspirin in patients receiving nitrate therapy(rate 7.13 per 1,000 patients). However, a low rate of generic prescribing (4.6%) was found amongst general practitioners in the study. The largest variability in prescribing was seen with the prescribing of peripheral and cerebral vasodilators (75th/25th centile=5.6) and the prescription of long-acting sulphonylureas (75th/25th centile=66.6).

CONCLUSIONS

Quality indicators based on aggregate prescribing provide valuable information on prescribing standards and should be developed with the close involvement of prescribers.

The influence of guidelines on the use of statins: analysis of prescribing trends 1998-2002

AIMS

To monitor statin prescribing trends over time in order to determine whether prescribers were influenced by study results and/or clinical guidelines in terms of type and dosage of statin prescribed.

METHODS

The GMS (General Medical Services) prescription database in Ireland was used to identify a cohort of patients, prescribed statins, in order to investigate prescribing trends from January 1998-December 2002. Statin prescribing rates for patients with ischaemic heart disease and diabetes were compared with rates in the general GMS population. Logistic regression analysis was used in patients with ischaemic heart disease and diabetes and adjusted odds ratios and 95% confidence intervals presented.

RESULTS

Increased statin prescribing over time was noted (test for linear trend P < 0.0001). Pravastatin was the most frequently prescribed, followed by atorvastatin; simvastatin and fluvastatin showed lower rates of prescribing. Atorvastatin showed the greatest increased rate over time. An increase in the overall dose prescribed (test for trend P < 0.01) was chiefly due to increases in pravastatin dose, but doses were still below those recommended from clinical trials. Statins were prescribed more frequently in patients with ischaemic heart disease and diabetes, 44% (95% CI 43-45%) compared with the total GMS population, 7.7% (95% CI 7.6-7.8%), by December 2002. However, statins were only prescribed to 52% (95% CI 51-53%) of ischaemic heart disease patients and 40% (95% CI 39-41%) of patients with diabetes by December 2002. Patients aged 45-64 years were more likely to receive statins, compared with those aged 65 years and older.

CONCLUSION

These findings suggest that the beneficial effects of statins shown in clinical studies may not be achieved in practice.

Initial uptake and evidence of safe prescribing practice with Buproprion (Zyban)

PURPOSE

To study the effect of safety concerns and the introduction of freely available nicotine replacement therapy (NRT) on the prescribing of Buproprion within the General Medical Services (GMS) scheme in Ireland.

METHODS

Using the state-supported GMS prescription database in Ireland, we identified 8166 patients who were prescribed Buproprion and 18,450 patients who were prescribed NRT over a 12-month-period.

RESULTS

A decline in the prescribing of Buproprion was noted which coincided with concerns regarding the safety of the drug but which preceded the introduction of NRT to the GMS. Furthermore, patients who were prescribed Buproprion were less likely to be co-prescribed potentially interacting drugs (odds ratio (OR): 0.48, 95% confidence intervals (CI): 0.42, 0.54) or drugs known to reduce seizure threshold (OR: 0.63, 95% CI: 0.6, 0.67) indicating good prescribing practice. Patients aged 65 years or more were less likely to be prescribed any form of smoking cessation therapy compared with those aged <65 years (OR: 0.23, 95% CI: 0.22-0.24) indicating that such therapy was targeted at those most likely to benefit.

CONCLUSIONS

We provide evidence that prescribers exercised caution in the prescription of Buproprion and were likely to have been influenced both by the safety concerns and the introduction of freely available NRT to the GMS population.

Prescription patterns in the elderly population--"new" versus "old" medical card holders

INTRODUCTION

In July 2001, the GMS Scheme was extended to the whole elderly population aged 70 and over, permitting access to medical care services free of charge. We undertook a study to compare prescribing patterns between those relatively affluent people referred to as "new" over 70s with those relatively deprived people referred to as "old" over 70's, over the 18 months since the introduction of the scheme. Patients who had received a prescription for antibacterials, diuretics, psycholeptics, psychoanaleptics, statins, b-blockers, antithrombolytics, antianaemic drugs and drugs for obstructive airway diseases, were identified over the 18 month period using the GMS database. We also compared the average defined daily dose (DDD) received per month for each of the therapies above.

RESULTS

All therapies directed at treatment were significantly more likely to be prescribed to the old over 70's, such as the vasodilators (OR=1.59, 1.51-1.67), peptic ulcer drugs (OR=1.37, 1.33-1.43) and the antibacterials (OR=1.37, 1.33-1.41) with the exception of those associated with cardiovascular prevention; statins (OR=0.88, 0.85-0.92), beta-blockers (OR=0.95, 0.92-0.98) and antithrombolytics (OR=0.96, 0.93-0.99). The old over 70's received more prescriptions with a higher than the average DDD per month for vasodilators, diuretics, and drugs for obstructive airway disease. This study highlights a potential inequality in prescribing in primary care, evident following a change in the health policy in Ireland. These results suggest that differences in socio-economic status (such as income) and morbidity may be associated with differences in prescribing by GPs.

Community-based study of atrial fibrillation and stroke prevention

The benefits of anticoagulation and antiplatelet agents for stroke prevention in atrial fibrillation (AF) have been established. There is little data on the use of this form of stroke prevention in patients with AF in Ireland. To determine whether adequate stroke prevention measures are taken regarding anticoagulation and aspirin use for patients in the community with chronic AF. Audit of general medical services (GMS) patients with atrial fibrillation in two Dublin general practices. A total of 70 patients with AF were identified from 2684 GMS patients in the two practices: contraindications to anticoagulation were established in 26 of these. In those for whom warfarin was indicated, 21 of 44 (47%) were not anticoagulated. In those not anticoagulated and where aspirin was not contra-indicated, 20 of 42 were not on aspirin. Our study found that almost one third of patients with AF could be anticoagulated but were not, and the alternative of aspirin was only used in just over one half of patients. This represents a lost opportunity for stroke prevention. Various approaches should be explored to remedy this.

Influence of material deprivation on prescribing patterns within a deprived population

OBJECTIVE

To study the effect of material deprivation on prescribing trends in primary care, using a locally derived deprivation score.

METHODS

A retrospective analysis of prescribing trends linked to material deprivation by district electoral division (DED) in the Eastern Region of the General Medical Services in Ireland (population of 334,031) was performed. Standardised prescribing ratios were determined for a number of drug classes, including those that could be used to identify particular diseases for 181,647 patients who were assigned a locally derived material deprivation score.

RESULTS

Prescribing rates for a number of medications including anti-asthma, nitrate and benzodiazepine medications increased, whilst the prescribing of other medications such as anti-parkinsonian and antidepressive agents decreased with increasing deprivation.

CONCLUSIONS

Our results suggest that, even within a population considered to be economically deprived, different levels of deprivation may significantly influence general practitioner prescribing patterns. Within the group of centrally active medications, the prescription of symptomatic medications increased with increasing material deprivation, whilst the prescription of disease-specific medications decreased with increasing material deprivation.

Under-prescribing of cardiovascular therapies for diabetes in primary care

OBJECTIVE

To determine the extent to which cardiovascular therapies are prescribed in primary care for those with diabetes, compared with those without diabetes.

METHODS

Population study of patients with and without diabetes identified using a national primary care prescribing database. All patients receiving a prescription for any diabetes therapy, including insulin and oral hypoglycaemic drugs, or diagnostic test kit for glucose ( n=8523) and those receiving no such therapies ( n=145,756) during a 1-year period (September 1999-August 2000) in the Eastern Regional Health Authority of Ireland were identified. In addition, a sub-set of patients receiving a nitrate prescription, a marker for ischaemic heart disease (IHD), were also identified ( n=14,826). Odds ratios and 95% confidence intervals for prescribing of cardiovascular therapies between those with diabetes and those without, adjusted for age and gender, were calculated using logistic regression.

RESULTS

The proportion of those (and 95% CES) with diabetes and IHD prescribed secondary preventative therapies was 37.3% (35.0, 39.6) for statins, 55.3% (53.0, 57.6) for angiotension converting enzyme inhibitors, 34.7% (32.5, 36.9) for beta blockers, 73.3% (71.2, 75.4) for aspirin, 4.4% (3.4, 5.4) for angiotensin-II antagonists and 2.5% (1.8, 3.2) for fibrates. The adjusted odds ratios for prescribing in those with diabetes compared with those without are 1.44 (1.30, 1.61) for statins, 3.09 (2.79, 3.42) for angiotension converting enzyme inhibitors, 0.82 (0.74, 0.91) for beta blockers, 1.23 (1.09, 1.38) for aspirin, 1.47 (1.13, 1.87) for angiotensin-II receptor blockers and 4.23 (2.88, 6.14) for lipid-lowering fibrates.

CONCLUSION

The greater rate of prescribing of cardiovascular therapies in those with diabetes relative to those without is not unexpected given the higher risk of coronary heart disease in those with diabetes. However, the proportion of patients with diabetes, particularly those with established IHD, prescribed cardiovascular therapies is considerably below that recommended in local and international guidelines.

Prescription monitoring in an Irish hospital

The prescribing of medicines is an integral part of the provision of healthcare and represents a relatively safe, effective and inexpensive mode of treatment. Hospital prescribing is of importance not alone for patients but also for the impact that it has on the prescribing of drugs in the community. We conducted a 'snap-shot' study of 1,488 hospital prescriptions and assessed such areas as legibility, generic prescribing and drug dosage. The average number of active prescriptions per patient was 5.47 for medical in-patients and 5.05 for surgical in-patients. 5% of prescriptions were deemed illegible and the rate of generic prescribing was relatively low. However the rate of compliance with the hospital formulary was good. The spectrum of drugs prescribed changed significantly from a previous study performed in 1987. Continuous review of doctors' prescribing habits will ensure the safe and economic use of medications.

Comparison of secondary prevention of heart disease in Europe: lifestyle getting worse, therapy getting better in Ireland

We compared the implementation of secondary prevention some 18 months following acute myocardial infarction or coronary artery bypass surgery in Ireland in 1994 to that in 15 European countries, including Ireland, in 2000. While there were substantial improvements in the use of statins, b-blockers and the availability of rehabilitation programmes since the early 1990s, more patients now smoke, take no exercise and are overweight. The prevalence of non-insulin dependent diabetes has increased by 70%. In comparison with other European countries, we have the highest use of aspirin and the highest prevalence of smoking in women. Despite a considerable improvement in the use of drug therapy we will not achieve the full potential of secondary prevention unless lifestyle factors, including smoking, overweight and exercise receive greater attention by patients with coronary heart disease.

Inequalities in prescribing of secondary preventative therapies for ischaemic heart disease in Ireland

The study aim is to quantify the variation in prescribing rates of secondary preventative therapies for Ischaemic Heart Disease (IHD) across regions, age and gender. Patients receiving any prescriptions for a nitrate during a one year period (September 1999-August 2000) were considered using a national primary care prescribing database. Age-sex standardised prescribing rates of four secondary preventative therapies for IHD (Ace inhibitors, beta-blockers, aspirin, statins) were calculated for each region. Wide variations between regions were observed with significantly higher variability for Ace inhibitors compared with aspirin (F-ratio=22.8, p<0.001). Men were more likely to prescribed these therapies and the elderly were less likely (except Ace inhibitors). The study suggests that access to secondary preventative therapy is not equitable across regions, gender and age in Ireland. The wide variability may be due to uncertainty in prescribing secondary preventative therapies and/or variability in clinical need between regions.

St Johns wort increases expression of P-glycoprotein: implications for drug interactions

AIMS

St John's Wort (SJW) is widely used in the treatment of depression but concerns have been raised about its potential to interact with other drugs. Co-administration with SJW has resulted in significant reductions in trough plasma concentrations of indinavir and cyclosporin [1, 2]. Induction of cytochrome P450 3A4 (CYP3A4) has been implicated as the most likely interaction mechanism. However, the magnitude of the interaction seen in clinical practice is greater than that predicted by in vitro studies suggesting additional interaction mechanisms may exist. As indinavir and cyclosporin are substrates for both CYP3A4 and the multi drug transporter P-glycoprotein we hypothesized that modulation of P-glycoprotein expression and function by SJW may contribute to the development of potentially harmful drug-drug interactions.

METHODS

Healthy volunteers were randomized to either SJW (0.15%) 600 mg three times daily for 16 days (n = 15) or placebo (n = 7). Blood samples were obtained for P-glycoprotein expression and function at baseline, 16 and 32 days post treatment. Peripheral blood lymphocytes (PBMCs) were isolated by Ficoll density gradient centrifugation, fixed and permeabilized. Cells were stained with a P-glycoprotein specific antibody, quantified by flow cytometry and median fluorescence intensity (MFI) values obtained. Vimentin and IE (nonsense antibody) were used as controls. The presence of the MDR 1 gene product was confirmed by RT-PCR. P-glycoprotein mediated drug efflux was determined as a function of rhodamine efflux in the absence and presence of ritonavir. Data are expressed as mean +/- s.d. and were subjected to nonparametric analysis.

RESULTS

P-glycoprotein expression increased 4.2 fold from baseline in subjects treated with SJW (7.0 +/- 1.9 vs 29.5 +/- 14.3 (MFI); P < 0.05). There was no effect with placebo (5.1 +/- 1.3 vs 6.0 +/- 1.9 MFI). SJW increased P-glycoprotein mediated rhodamine efflux (reduced ratio) compared with baseline (0.12 +/- 0.04 vs 0.24 +/- 0.18 P < 0.05). There was no change with placebo. Ritonavir (5 microm) inhibited P-glycoprotein mediated efflux in both groups producing greater intracellular accumulation of rhodamine. However, this effect was attenuated following treatment with SJW (23.9 +/- 15.3% vs 75.4 +/- 16.4% P < 0.05).

CONCLUSIONS

SJW increased expression and enhanced the drug efflux function of the multi drug transporter P-glycoprotein in PBMCs of healthy volunteers. This may represent a second mechanism for the drug-herb interactions seen in clinical practice and account for the discrepancies between in vitro and in vivo data. Since P-glycoprotein and CYP3A4 have distinct though overlapping substrates, patients receiving drugs, which are P-glycoprotein substrates should be warned against self-medication with SJW as clinically significant drug interactions may occur.

Pharmacoepidemiology--an Irish perspective

The Irish healthcare system is a mixture of free, state-supported and private medicine. The state-supported General Medical Services (GMS) scheme maintains a large prescription database, which has been used to conduct pharmacoepidemiological studies in Ireland. The dataset is anonymized thus maintaining patient and prescriber confidentiality. Three recent studies using this data are described, two of which outline the effect of regulatory advice and the media on prescribing patterns and one which describes the development of an index of prescribing quality which may be applied to prescription data. The GMS prescription database is presently being complemented by a database for some 0.7 million people who seek reimbursement for prescriptions from individuals or families in excess of 42 Pounds per month which together will have an important role for the continued development of pharmacoepidemiology in Ireland.

Lack of symptom benefit following presumptive Helicobacter pylori eradication therapy in primary care

BACKGROUND

Helicobacter pylori eradication regimens have failure rates under 10%, however little information is available on the effect of treatment success in reducing the subsequent prescription of anti-ulcer medications in primary care.

AIMS

To determine, using a large prescription database in eastern Ireland, the success of presumptive eradication therapy in improving symptoms of dyspepsia in primary care, as judged by a reduction in the subsequent prescription of anti-ulcer medications.

METHODS

In a cross-sectional study, we identified 3847 patients who received a prescription for eradication therapy for Helicobacter pylori, including 826 who were followed for 9-11 months. Those who subsequently received anti-ulcer medications were deemed failures to obtain symptom relief.

RESULTS

For 3847 patients with a median follow-up of 8 months, the failure rate was 49%. Of 826 patients, followed for a longer period (9-11 months), the overall failure rate was 56% (range 44-62% depending on the eradication regimen used). Age over 65 years (hazard ratio=1.57, 95% confidence interval= 1.29-1.91, P < 0.001), prior use of anti-ulcer medications (hazard ratio=1.97, 95% confidence interval=1.63-2.37, P < 0.001) and prior use of aspirin/NSAIDs (hazard ratio=1.43, 95% confidence interval=1.18-1.73, P < 0.001) all predicted failure to obtain relief of symptoms of dyspepsia from eradication therapy.

CONCLUSIONS

Such high failure rates of eradication therapy in reducing the subsequent consumption of anti-ulcer medications have both clinical and economic implications for the use of eradication therapy for Helicobacter pylori in primary care.

Effect of sildenafil on blood pressure and arterial wave reflection in treated hypertensive men

As the effects of sildenafil are in part mediated by enhancing the action of nitric oxide and nitrates given acutely markedly reduce early wave reflection, we explored the effects of a single oral dose of sildenafil citrate (50 mg) on blood pressure and arterial wave reflection in treated hypertensive men in a single-blind randomised placebo controlled crossover study. Eight men (aged 57-76 years) with well controlled hypertension and erectile dysfunction and no contraindications to the use of sildenafil, were given either sildenafil 50 mg or placebo orally, with the second drug being given 2 weeks later. Blood pressure and heart rate with an automated digital oscillometric device (Omron) HEM-705 CP) and the augmentation index, a measure of arterial wave reflection in the aorta derived using radial applanation tonometry, were measured before and at 15-min intervals for 2 h thereafter. The extent of individual maximum reductions (mm Hg) from baseline in systolic (24 +/- 10 vs. 6 +/- 8, P < 0.05) and diastolic blood pressure (8 +/- 5 vs. 3 +/- 2, P < 0.05) occurred on the sildenafil study day. On average the brachial blood pressure at 75 min following sildenafil was 17/11 mm less than on the placebo day (P < 0.01). Augmentation index was also reduced significantly at 90 min (P < 0.05) suggesting reduced vascular tone in the arteries. The area under the brachial and aortic blood pressure and augmentation index time curve (by the trapezoidal rule corrected for baseline reading) was significantly lower (P < 0.05) on the sildenafil study day. The study shows that the peripheral vasodilatory effects of sildenafil, possibly related to nitric oxide, are accompanied by a fall in systemic blood pressure and reduced arterial wave reflection.