Long-term secondary prevention and outcome following acute coronary syndrome: real-world results from the Swedish Primary Care Cardiovascular Database

AIMS

Most studies of treatment adherence after acute coronary syndrome (ACS) are based on prescribed drugs and lack long-term follow-up or consecutive data on risk factor control. We studied the long-term treatment adherence, risk factor control, and its association to recurrent ACS and death.

METHODS AND RESULTS

We retrospectively included 3765 patients (mean age 75 years, 40% women) with incident ACS from 1 January 2006 until 31 December 2010 from the Swedish Primary Care Cardiovascular Database of Skaraborg. All patients were followed until 31 December 2014 or death. We recorded blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), recurrent ACS, and death. We used data on dispensed drugs to calculate the proportion of days covered for secondary prevention medications. Cox regressions were used to analyse the association of achieved BP and LDL-C to recurrent ACS and death. The median follow-up time was 4.8 years. The proportion of patients that reached BP of <140/90 mm Hg was 58% at Year 1 and 66% at Year 8. 65% of the patients reached LDL-C of <2.5 mmol/L at Year 1 and 56% at Year 8; however, adherence to statins varied from 43% to 60%. Only 62% of the patients had yearly measured BP, and only 28% yearly measured LDL-C. Systolic BP was not associated with a higher risk of recurrent ACS or death. Low-density lipoprotein cholesterol of 3.0 mmol/L was associated with a higher risk of recurrent ACS {hazard ratio [HR] 1.19 [95% confidence interval (CI) 1.00-1.40]} and death HR [1.26 (95% CI 1.08-1.47)] compared with an LDL-C of 1.8 mmol/L.

CONCLUSION

This observational long-term real-world study demonstrates low drug adherence and potential for improvement of risk factors after ACS. Furthermore, the study confirms that uncontrolled LDL-C is associated with adverse outcome even in this older population.

Long-term risk-factor control and secondary prevention are insufficient after first TIA: Results from QregPV

INTRODUCTION

Long-term risk-factor control and secondary prevention are not well characterized in patients with a first transient ischemic attack (TIA). With baseline levels as reference, we compared primary-care data on blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), smoking, and use of antihypertensives, statins and antiplatelet treatment/oral anticoagulation (APT/OAC) during 5 years after a first TIA.

PATIENTS AND METHODS

Patients in QregPV, a Swedish primary-care register for the Region of Västra Götaland, with a first TIA discharge diagnosis from wards proficient in stroke care 2010 to 2012 were identified and followed up to 5 years. BP, LDL-C, smoking, use of antihypertensives, statins, APT/OAC, and achievement of target levels were calculated. We used logistic mixed-effect models to analyze the effect of follow-up over time on risk-factor control and secondary prevention treatment.

RESULTS

We identified 942 patients without prior cerebrovascular disease who had a first TIA. Compared to baseline, the first year of follow-up was associated with improvements in concomitant attainment of BP <140/90 mmHg, LDL-C < 2.6 mmol/L and non-smoking, which rose from 20% to 33% (OR 2.08, 95% CI 1.38-3.13), but then stagnated in years 2-5. In the first year of follow-up, 47% of patients had complete secondary prevention treatment (antihypertensives, APT/OAC and statin), but continued follow-up was associated with a yearly decrease in secondary prevention treatment (OR 0.94, 95% CI 0.94-0.98).

CONCLUSION

Risk-factor control was inadequate, leaving considerable potential for improved secondary prevention treatment after a first TIA in Swedish patients followed up to 5 years.

The effect of statins on mortality and cardiovascular disease in primary care hypertensive patients without other cardiovascular disease or diabetes

AIMS

Studies in primary healthcare (PHC) assessing the effect of primary prevention with statins on mortality and cardiovascular disease (CVD) are scarce. This study aimed to estimate the effect of statins on all-cause mortality, cardiovascular mortality, myocardial infarction (MI), and stroke in individuals in PHC with hypertension without CVD or diabetes.

METHODS AND RESULTS

Using the Swedish PHC quality assurance register QregPV, the study included 13 193 individuals with hypertension without CVD or diabetes, who had filled a first statin prescription between 2010 and 2016, and 13 193 matched controls without a filled statin prescription at the index date. Controls were matched on sex and propensity score using clinical data and data from national registers on comorbidities, prescriptions, and socioeconomic status. The effect of statins was estimated in Cox regression models. During a median of 4.2 years of follow-up, 395 individuals in the statin group vs. 475 in the control group died, 197 vs. 232 died of cardiovascular disease, 171 vs. 191 had an MI, and 161 vs. 181 had a stroke. The treatment effect of statins was significant for all-cause mortality [hazard ratio (HR) 0.83, 95% confidence interval (CI) 0.74-0.93] and cardiovascular mortality (HR 0.85, 95% CI 0.72-0.998). Overall, no significant treatment effect of statins was seen for MI (HR 0.89, 95% CI 0.74-1.07), but there was a significant interaction with sex (P = 0.008) with decreased risk of MI for women but not for men (HR 0.66, 95% CI 0.49-0.88 vs. HR 1.09, 95% CI 0.86-1.38).

CONCLUSION

Primary prevention with statins in PHC was associated with reduced risk of all-cause mortality, cardiovascular mortality, and in women, lower risk of MI.

Hypertension: sex-related differences in drug treatment, prevalence and blood pressure control in primary care

Antihypertensive treatment is equally beneficial for reducing cardiovascular risk in both men and women. Despite this, the drug treatment, prevalence and control of hypertension differ between men and women. Men and women respond differently, particularly with respect to the risk of adverse events, to many antihypertensive drugs. Certain antihypertensive drugs may also be especially beneficial in the setting of certain comorbidities - of both cardiovascular and extracardiac nature - which also differ between men and women. Furthermore, hypertension in pregnancy can pose a considerable therapeutic challenge for women and their physicians in primary care. In addition, data from population-based studies and from real-world data are inconsistent regarding whether men or women attain hypertension-related goals to a higher degree. In population-based studies, women with hypertension have higher rates of treatment and controlled blood pressure than men, whereas real-world, primary-care data instead show better blood pressure control in men. Men and women are also treated with different antihypertensive drugs: women use more thiazide diuretics and men use more angiotensin-enzyme inhibitors and calcium-channel blockers. This narrative review explores these sex-related differences with guidance from current literature. It also features original data from a large, Swedish primary-care register, which showed that blood pressure control was better in women than men until they reached their late sixties, after which the situation was reversed. This age-related decrease in blood pressure control in women was not, however, accompanied by a proportional increase in use of antihypertensive drugs and female sex was a significant predictor of less intensive antihypertensive treatment.

The Value of Exercise Electrocardiography in Outpatients with Stable Chest Pain and Low Pre-Test Probability of Significant Coronary Artery Disease

The role of exercise electrocardiography (ECG) in the investigation of stable chest pain has been questioned. The American Heart Association guidelines suggest the use of exercise ECG in patients with stable chest pain and low pre-test probability (PTP) of significant coronary artery disease, while the European Society of Cardiology Guidelines does not. This retrospective observational study aimed to assess the usefulness of exercise ECG in the low-PTP population with stable chest pain. We reviewed the medical records for all outpatient exercise ECGs conducted because of stable chest pain at the Department of Medicine and Emergency, Sahlgrenska University Hospital, Mölndal, Sweden, during 2016-2018. The identified patients were categorized in low-, intermediate-, or high-risk pre-test probability of significant coronary artery disease. All low-PTP patients were followed for one year post investigation for the incidence of acute coronary syndrome and all-cause mortality. Thus, 505 patients (mean age 60 years, 56% women) with low PTP were included in the study. Only four patients (0.6%) experienced incident myocardial infarction (three patients) or all-cause mortality (one patient). The negative predictive value of exercise ECG was 99.7%, and the positive predictive value was 28.6%. In this low-PTP population, exercise ECG yields a good negative predictive value and a poor positive predictive value.

Prediabetes and incident heart failure in hypertensive patients: Results from the Swedish Primary Care Cardiovascular Database

BACKGROUNDS AND AIMS

The cardiovascular risk conferred by concomitant prediabetes in hypertension is unclear. We aimed to examine the impact of prediabetes on incident heart failure (HF) and all-cause mortality, and to describe time in therapeutic blood pressure range (TTR) in a hypertensive real-world primary care population.

METHODS AND RESULTS

In this retrospective cohort study, 9628 hypertensive individuals with a fasting plasma glucose (FPG) in 2006-2010 but no diabetes, cardiovascular or renal disease were followed to 2016; median follow-up was 9 years. Prediabetes was defined as FPG 5.6-6.9 mmol/L, and in a secondary analysis as 6.1-6.9 mmol/L. Study outcomes were HF and all-cause mortality. Hazard ratios (HR) were compared for prediabetes with normoglycemia using Cox regression. All blood pressure values from 2001 to the index date (first FPG in 2006-2010) were used to calculate TTR. At baseline, 51.4% had prediabetes. The multivariable-adjusted HR (95% confidence intervals) was 0.86 (0.67-1.09) for HF and 1.06 (0.90-1.26) for all-cause mortality. For FPG defined as 6.1-6.9 mmol/L, the multivariable-adjusted HR were 1.05 (0.80-1.39) and 1.42 (1.19-1.70), respectively. The prediabetic group had a lower TTR (p < 0.05).

CONCLUSIONS

Prediabetes was not independently associated with incident HF in hypertensive patients without diabetes, cardiovascular or renal disease. However, prediabetes was associated with all-cause mortality when defined as FPG 6.1-6.9 mmol/L (but not as 5.6-6.9 mmol/L). TTR was lower in the prediabetic group, suggesting room for improved blood pressure to reduce incident heart failure in prediabetes.

Long-term risk factor control after acute coronary syndrome; results from the Swedish primary care cardiovascular database

Background

Most secondary prevention studies after acute coronary syndrome (ACS) have relatively short follow-up time, and less is known about long-term risk factor control in patients after ACS.

Purpose

We aimed to study and describe the long-term risk factor control, treatment adherence and outcome after ACS.

Methods

We identified 3765 patients (mean age 75 years, 40% women) with an incident ACS between 2006 and 2010 in the Swedish Primary Care Cardiovascular Database. All participants were followed from index ACS until 31 December 2014 or death. We annually recorded blood pressure, low density lipoprotein cholesterol (LDL-C), dispensed prescription of drugs, recurrent ACS, and death. Data were collected from electronic medical records at the primary care centres, the Swedish Prescribed Drug Register, the Swedish Patient Register, and the Cause of Death Register. We calculated annually proportion of days covered (PDC) for secondary prevention medication. PDC value of ≥80% was considered cut off for medication adherence.

Results

The median follow-up time was 4.8 years (min 1.8 and max 8.0). 1890 new ACS-events were recorded during the follow up; the annual incidence of recurrent ACS was 17.3%, 12.9%, 8.9%, 8.0%, 7.6%, 6.5%, 5.2%, and 5.0% (for year 1 to year 8 respectively). 1859 (49.4%) patients died during the follow up. The annual incidence of death was 19.9%, 7.9%, 7.1%, 8.3%, 7.9%, 8.2%, 6.7%, and 6.4% (for year 1 to year 8 respectively). The annual proportion of patients that achieved the blood pressure target &lt;140/90 mm Hg was 57.8%, 60.9%, 62.7%, 63.3%, 64.9%, 63.1%, 62.4%, and 66.1% (for year 1 to year 8 respectively). The annual mean number of antihypertensive medications for each patient was 1.5, 1.3, 1.3, 1.3, 1.4, 1.4, 1.4, and 1.5 (for year 1 to year 8 respectively). The annual proportion of patients that achieved LDL-C &lt;1.8 mmol/L was 23.1%, 21.7%, 19.8%, 18.2%, 15.7%, 19.6%, 18.3%, and 16.7% (for year 1 to year 8 respectively). The annual proportion of patients in treatment with statins was 55.3%, 57.5%, 58.7%, 59.2%, 63.0%, 63.7%, 64.1%, and 67.7% (for year 1 to year 8 respectively). The annual proportion of patients in treatment with acetylsalicylic acid was 79.6%, 76.4%, 76.2%, 78.9%, 78.3%, 79.2%, and 80.8% % (for year 1 to year 8 respectively). The annual proportion of patients in treatment with P2Y12-inhibitors was 24.3%, 7.2%, 5.4%, 6.0%, 7.2%, 8.1%, 7.9% and 8.2% (for year 1 to year 8 respectively).

Conclusion

This retrospective long-term real-world study from primary care demonstrates a large potential for improvement of risk factor control in patients after ACS. More specific, this study demonstrates underutilized treatment with antihypertensive medication and statins, while adherence to antiplatelet therapy was found to be high.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Astra Zeneca

Socioeconomic status affects achievement of blood pressure target in hypertension: contemporary results from the Swedish primary care cardiovascular database

OBJECTIVE

To assess the relation between socioeconomic status and achievement of target blood pressure in hypertension.

DESIGN

Retrospective longitudinal cohort study between 2001 and 2014.

SETTING

Primary health care in Skaraborg, Sweden.

SUBJECTS

48,254 patients all older than 30 years, and 53.3% women, with diagnosed hypertension.

MAIN OUTCOME MEASURES

Proportion of patients who achieved a blood pressure target <140/90 mmHg in relation to the country of birth, personal disposable income, and educational level.

RESULTS

Patients had a lower likelihood of achieving the blood pressure target if they were born in a Nordic country outside Sweden [risk ratio 0.92; 95% confidence interval (CI) 0.88-0.97], or born in Europe outside the Nordic countries (risk ratio 0.87; 95% CI 0.82-0.92), compared to those born in Sweden. Patients in the lowest income quantile had a lower likelihood to achieve blood pressure target, as compared to the highest quantile (risk ratio 0.93; 95% CI 0.90-0.96). Educational level was not associated with outcome. Women but not men in the lowest income quantile were less likely to achieve the blood pressure target. There was no sex difference in achieved blood pressure target with respect to the country of birth or educational level.

CONCLUSION

In this real-world population of primary care patients with hypertension in Sweden, being born in a foreign European country and having a lower income were factors associated with poorer blood pressure control.KEY POINTSThe association between socioeconomic status and achieving blood pressure targets in hypertension has been ambiguous.•In this study of 48,254 patients with hypertension, lower income was associated with a reduced likelihood to achieve blood pressure control.•Being born in a foreign European country is associated with a lower likelihood to achieve blood pressure control.•We found no association between educational level and achieved blood pressure control.

Trends in blood pressure, blood lipids, and smoking from 259 753 patients with hypertension in a Swedish primary care register: results from QregPV

AIMS

To describe 8-year trends in blood pressure (BP) control, blood lipid control, and smoking habits in patients with hypertension from QregPV, a primary care register in the Region of Västra Götaland, Sweden.

METHODS AND RESULTS

QregPV features clinical data on BP, low-density lipoprotein cholesterol (LDL-C), and smoking habits in 392 277 patients with hypertension or coronary heart disease or diabetes mellitus or any combination of the three diagnoses. Data from routine clinical practice have been automatically reported on a monthly basis to QregPV from all primary care centres in Västra Götaland (population 1.67 million) since 2010. Additional data on diagnoses, dispensed drugs and socioeconomic factors were acquired through linkage to regional and national registers. We identified 259 753 patients with hypertension, but without coronary heart disease and diabetes mellitus, in QregPV. From 2010 to 2017, the proportion of patients with BP <140/90 mmHg increased from 38.9% to 49.1%, while the proportion of patients with LDL-C <2.6 mmol/L increased from 19.7% to 21.1% and smoking decreased from 15.7% to 12.3%. However, in 2017, only 10.0% of all patients with hypertension had attained target levels of BP <140/90 mmHg, LDL-C < 2.6 mmol/L while being also non-smokers. The remaining 90.0% were still exposed to at least one uncontrolled, modifiable risk factor for cardiovascular disease.

CONCLUSIONS

These regionwide data from eight consecutive years in 259 753 patients with hypertension demonstrate a large potential for risk factor improvement. An increased use of statins and antihypertensive drugs should, in addition to lifestyle modifications, decrease the risk of cardiovascular disease in these patients.

Blood pressure levels and risk of haemorrhagic stroke in patients with atrial fibrillation and anticoagulants: results from a primary care cohort with hypertension

Background

Haemorrhagic stroke (HS) is a serious condition that kills and debilitates many of those afflicted by it. Hypertension and oral anticoagulation (OAC) are independent risk factors for HS. Many patients with atrial fibrillation (AF) have hypertension and OAC. The concomitance of hypertension and OAC confers an even higher risk of haemorrhagic stroke, but less is known about the association between specific blood pressure levels and the risk of HS in patients with AF and OAC.

Purpose

To assess the risk of haemorrhagic stroke at different systolic blood pressure (SBP) levels in a primary care population with hypertension, AF and OAC.

Methods

We identified 3972 patients with hypertension, AF and OAC in a primary care database in southern Sweden. We followed patients from Jan 1, 2006 until a first event of HS, death, cessation of OAC or Dec 31, 2016. HS was defined as ICD-10 diagnosis codes: I60, I61, and I62. We analysed the association between SBP levels and HS by dividing SBP into five categories: &lt;130, 130–139, 140–159, 160–179 and ≥180 mmHg. We also fitted a spline curve to visualise the relationship between SBP and HS. Hazard ratios (HR) were calculated for the SBP categories with a Cox proportional hazards model. The 130–139 group was used as a reference in the model. We identified age, sex, previous stroke, platelet inhibitor treatment, alcohol abuse and smoking as possible confounders with a directed acyclic graph and included them as co-variates in the model.

Results

We identified 51 cases of HS during follow-up. In the categorical analysis of SBP, point estimates of HRs for HS increased gradually from the lowest SBP category to the 160–179 category. Only the 160–179 category had a significantly different HR (3.76, CI 1.56–9.04) than the reference 130–139 category, however. See Table 1. No other co-variates were significantly associated with HS. The spline curve, Figure 1, illustrates a significantly increased HR for HS in the 140–175 SBP range.

Conclusions

In this real-world primary care cohort with hypertension, AF and OAC, we found that SBP in the 160–179 mmHg range was significantly associated with an increased risk of haemorrhagic stroke. Our findings emphasise the importance of blood pressure control in this patient category.

Figure 1. Continuous and categorical SBP & HS risk

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The study was financed by grants from the Swedish state under the agreement between the Swedish government and the country councils, the ALF-agreement.

Relation Between Lipid Profile and New-Onset Atrial Fibrillation in Patients With Systemic Hypertension (From the Swedish Primary Care Cardiovascular Database [SPCCD])

The relation between dyslipidemia and atrial fibrillation (AF) development is still controversial. To assess the impact of lipid profile on new-onset AF, we followed 51,020 primary-care hypertensive patients without AF at baseline. After a mean follow-up time of 3.5 years, AF occurred in 2,389 participants (4.7%). We evaluated the association between total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, and new-onset AF. In a Poisson regression model fully adjusted for common risk factors of AF, we found that 1.0 mmol/l (39 mg/dl) increase in total cholesterol was associated with 19% lower risk of new-onset AF (95% confidence interval [CI] 9% to 28%), and 1.0 mmol/l (39 mg/dl) increase in low-density lipoprotein cholesterol was associated with 16% lower risk of new-onset AF (95% CI 3% to 27%). Gender-specific Poisson regression analyses revealed that increase in total cholesterol by 1.0 mmol/l (39 mg/dl) was found to be associated with lower risk of new-onset AF with 21% in men (95% CI 8% to 32%), and 18% in women (95% CI 1% to 31%). There was no association between high-density lipoprotein cholesterol or triglycerides and new-onset AF, neither in the whole population with respect to separate gender. In conclusion, in a large hypertensive population we found an inverse association between total cholesterol and new-onset AF for both men and women. Our results confirm previous reports of a dyslipidemia paradox, and extend these observations to the hypertensive population.

Primary aldosteronism and thyroid disorders in atrial fibrillation: A Swedish nationwide case–control study

Background

Atrial fibrillation is associated with hyperthyroidism. Patients with primary aldosteronism have an increased prevalence of atrial fibrillation. However, the prevalence of primary aldosteronism in the atrial fibrillation population is unknown.

Aim

This nationwide case–control study aimed to compare the prevalence of primary aldosteronism and thyroid disorders in patients with atrial fibrillation with that of age- and sex-matched controls.

Methods

We identified all atrial fibrillation cases in Sweden between 1987 and 2013 ( n = 713,569) by using the Swedish National Patient Register. A control cohort without atrial fibrillation was randomly selected from the Swedish Total Population Register with a case to control ratio of 1:2. This control cohort was matched for age, sex and place of birth ( n = 1,393,953).

Results

The prevalence of primary aldosteronism in December 2013 was 0.056% in the atrial fibrillation cohort and 0.024% in controls. At the same time, the prevalence of hypothyroidism was 5.9% in the atrial fibrillation cohort and 3.7% in controls. The prevalence of hyperthyroidism was 2.3% in the atrial fibrillation cohort and 0.8% in controls.

Conclusion

This study shows, for the first time, a doubled prevalence of primary aldosteronism in a large cohort of patients with atrial fibrillation compared with the general population. There is also an increased prevalence of hypo- and hyper-thyroidism in patients with atrial fibrillation compared with the general population.

Aldosterone to Renin Ratio as a Screening Instrument for Primary Aldosteronism in a Middle-Aged Population with Atrial Fibrillation

Atrial fibrillation seems to be overrepresented among patients with primary aldosteronism. The aim of this study was to determine the usefulness of aldosterone to renin ratio as a screening instrument for primary aldosteronism in an atrial fibrillation population with relatively low cardiovascular risk profile. A total of 149 patients <65 years and with history of AF were screened for primary aldosteronism using aldosterone to renin ratio. Pathologically increased aldosterone to renin ratio (>65 pmol/mIU) was found in 15 participants (10.1%). Further investigation of the positive screened participants and confirmatory saline infusion test resulted in a diagnosis of primary aldosteronism in four individuals out of 149 (2.6%). Three out of the four individuals with primary aldosteronism had previously been diagnosed with hypertension, but only one out of the four had uncontrolled blood pressure, that is, >140/90 mmHg. All participants had normal potassium levels. Individuals with increased aldosterone to renin ratio had significantly higher mean systolic and diastolic blood pressure in comparison to participants with normal aldosterone to renin ratio (136 vs. 126 mmHg, p=0.02 and 84 vs. 78 mmHg, p=0.02). These findings suggest that assessment of aldosterone to renin ratio can be useful for identification of underlying primary aldosteronism in patients with diagnosed atrial fibrillation and hypertension in spite of well controlled blood pressure and normokalemia.

Antihypertensive effect of low-frequency transcutaneous electrical nerve stimulation (TENS) in comparison with drug treatment

Hypertension is a major risk factor for vascular disease, yet blood pressure (BP) control is unsatisfactory low, partly due to side-effects. Transcutaneous electrical nerve stimulation (TENS) is well tolerated and studies have demonstrated BP reduction. In this study, we compared the BP lowering effect of 2.5 mg felodipin once daily with 30 min of bidaily low-frequency TENS in 32 adult hypertensive subjects (mean office BP 152.7/90.0 mmHg) in a randomized, crossover design. Office BP and 24-h ambulatory BP monitoring (ABPM) were performed at baseline and at the end of each 4-week treatment and washout period. Felodipin reduced office BP by 10/6 mmHg (p <0.001 respectively) and after washout BP rose to a level still significantly lower than at baseline. TENS reduced office BP by 5/1.5 mmHg (p <0.01, ns). After TENS washout, BP was further reduced and significantly lower than at baseline, but at levels similar to BP after felodipin washout and therefore reasonably caused by factors other than the treatment per se. ABPM revealed a significant systolic reduction of 3 mmHg by felodipin, but no significant changes were noted after TENS. We conclude that our study does not present any solid evidence of BP reduction of TENS.