A 10-Year Trend in Statin Use Among Older Adults in Australia: an Analysis Using National Pharmacy Claims Data

Statin-Associated Liver Dysfunction and Muscle Injury: epidemiology, Mechanisms, and Management Strategies

Surveillance of drug safety is an important aspect in the routine medical care. Adverse events caused by real-world drug utilization has become one of the leading causes of death and an urgent issue in the field of toxicology. Cardiovascular disease is now the leading cause of fatal diseases in most countries, especially in the elderly population who often suffer from multiple diseases and need long-term multidrug therapy. Among which, statins have been widely used to lower bad cholesterol and regress coronary plaque mainly in patients with hyperlipidemia and atherosclerotic cardiovascular diseases (ASCVD). Although the real-world benefits of statins are significant, different degrees and types of adverse drug reactions (ADR) such as liver dysfunction and muscle injury, have a great impact on the original treatment regimens as well as the quality of life. This review describes the epidemiology, mechanisms, early identification and post-intervention of statin-associated liver dysfunction and muscle injury based on the updated clinical evidence. It provides systematic and comprehensive guidance and necessary supplement for the clinical safety of statin use in cardiovascular diseases.

Patterns of Lipid Lowering Therapy Use Among Older Adults in a Managed Care Advantage Plan in the United States

Background: The prevalence of cardiovascular events is increasing. There are many new lipids lowering therapies available in recent years. Increased evidence through literature and guidelines suggests that the use of lipid lowering therapy (LLT) benefits patients who are at risk for cardiovascular events. Objective: The objective of this study was to describe the current LLT use as well as patterns of treatment modification among adults ≥ 65 years. Methods: A retrospective analysis of administrative claims data between January 2016 and May 2018 was conducted. Patients with a LLT refill and continuous enrollment during 1-year prior and 1-year follow-up were identified. The treatment episodes captured were interruption of therapy, intensity changes, dose changes, treatment augmentation, switching, and discontinuation. An analysis of treatment patterns among patients ≥75 years was also performed. Results: The study included 14,360 patients with a LLT of which 99% of patients were on statins as monotherapy or combination. Overall non-statin therapy use either as monotherapy or combination was 2.1%. There were significant differences among new initiators and existing users of therapy. Among prevalent users 57.4% had no changes in the follow-up period, 13.6% interrupted therapy, and 6.6% discontinued. Among new users, 47.9% patients had interrupted therapy, 25% had no changes, and 21.9% discontinued therapy. Conclusion: Most patients were on monotherapy and statins with low non-statin use. The new users among them were more likely to discontinue and interrupt therapy, highlighting the limitations and issues that older patients face that need to increase adherence.

Trends of hospitalisation for cardiovascular diseases among people with diabetes in Australia

OBJECTIVE

To describe trends in hospitalisation for subtypes of cardiovascular diseases among people with diabetes.

METHODS

The data sources included the Australian diabetes registry, admitted hospitalisation datasets, and death registry from 2011 to 2019. The outcomes comprised hospital admissions for: all CVD; all cerebrovascular diseases, ischaemic and haemorrhagic stroke; angina and ischaemic heart disease (AIHD); non-ST elevation myocardial infarction (NSTEMI), ST-elevation myocardial infarction (STEMI); atrial fibrillation and flutter (AFF). Data were analysed using Stata and Joinpoint regression software.Rates were standardised for age and sex. Annual percentage change (APC) was reported.

RESULTS

In type 1 diabetes, there were increases in hospitalisation for all cerebrovascular diseases (APC 4.5, 95 % CI: 1.2, 7.9) and ischaemic stroke (2.3, 95 % CI: 1.6, 3.0). There were declines in STEMI (-2.6, 95 % CI: -5.0, -0.1) and AIHD (-3.1, 95 % CI: -5.5, -0.7). In type 2 diabetes, hospitalisation for all CVD declined (-0.9, 95 % CI: -1.4, -0.3). Hospitalisation rates for ischaemic stroke increased (4.1, 95 % CI: 3.1, 5.1). There were declines in NSTEMI (-2.5, 95 % CI: -3.2, -1.8) and AIHD (-4.2, 95 % CI: -4.8, -3.5).

CONCLUSION

In type 1 and 2 diabetes, hospitalisation for ischaemic stroke increased while coronary diagnoses declined.

Temporal trends in chronic complications of diabetes by sex in community-based people with type 2 diabetes: the Fremantle Diabetes Study

BACKGROUND

Whether recent reductions in cardiovascular disease (CVD) events and mortality in type 2 diabetes apply equally to both sexes is largely unknown. The aim of this study was to characterize temporal changes in CVD events and related outcomes in community-based male and female Australian adults with type 2 diabetes or without known diabetes.

METHODS

Participants from the longitudinal observational Fremantle Diabetes Study Phases I (FDS1; n = 1291 recruited 1993-1996) and II (FDS2; n = 1509 recruited 2008-2011) and four age-, sex- and postcode-matched individuals without diabetes (FDS1 n = 5159; FDS2 n = 6036) were followed for first myocardial infarction, stroke, heart failure hospitalization, lower extremity amputation, CVD death and all-cause mortality. Five-year incidence rates (IRs) for males versus females in FDS1 and FDS2 were calculated, and IR ratios (IRRs) derived.

RESULTS

The FD1 and FDS2 participants were of mean age 64.0 and 65.4 years, respectively, and 48.7% and 51.8% were males. For type 2 diabetes, IRRs for all endpoints were 11-62% lower in FDS2 than FDS1 for both sexes. For participants without diabetes, IRRs were 8-56% lower in FDS2 versus FDS1 apart from stroke in females (non-significantly 41% higher). IRRs for males versus females across FDS phases were not significantly different for participants with type 2 diabetes or those without diabetes (P-values for male * FDS2 interaction ≥ 0.0.083 adjusted for age). For risk factors in participants with type 2 diabetes, greater improvements between FDS1 and FDS2 in smoking rates in males were offset by a greater reduction in systolic blood pressure in females.

CONCLUSIONS

The incidence of chronic complications in Australians with type 2 diabetes and without diabetes has fallen similarly in both sexes over recent decades, consistent with comparably improved overall CVD risk factor management.

Vitamin D supplementation and major cardiovascular events: D-Health randomised controlled trial

OBJECTIVE

To investigate whether supplementing older adults with monthly doses of vitamin D alters the incidence of major cardiovascular events.

DESIGN

Randomised, double blind, placebo controlled trial of monthly vitamin D (the D-Health Trial). Computer generated permuted block randomisation was used to allocate treatments.

SETTING

Australia from 2014 to 2020.

PARTICIPANTS

21 315 participants aged 60-84 years at enrolment. Exclusion criteria were self-reported hypercalcaemia, hyperparathyroidism, kidney stones, osteomalacia, sarcoidosis, taking >500 IU/day supplemental vitamin D, or unable to give consent because of language or cognitive impairment.

INTERVENTION

60 000 IU/month vitamin D₃ (n=10 662) or placebo (n=10 653) taken orally for up to five years. 16 882 participants completed the intervention period: placebo 8270 (77.6%); vitamin D 8552 (80.2%).

MAIN OUTCOME MEASURES

The main outcome for this analysis was the occurrence of a major cardiovascular event, including myocardial infarction, stroke, and coronary revascularisation, determined through linkage with administrative datasets. Each event was analysed separately as secondary outcomes. Flexible parametric survival models were used to estimate hazard ratios and 95% confidence intervals.

RESULTS

21 302 people were included in the analysis. The median intervention period was five years. 1336 participants experienced a major cardiovascular event (placebo 699 (6.6%); vitamin D 637 (6.0%)). The rate of major cardiovascular events was lower in the vitamin D group than in the placebo group (hazard ratio 0.91, 95% confidence interval 0.81 to 1.01), especially among those who were taking cardiovascular drugs at baseline (0.84, 0.74 to 0.97; P for interaction=0.12), although the P value for interaction was not significant (<0.05). Overall, the difference in standardised cause specific cumulative incidence at five years was -5.8 events per 1000 participants (95% confidence interval -12.2 to 0.5 per 1000 participants), resulting in a number needed to treat to avoid one major cardiovascular event of 172. The rate of myocardial infarction (hazard ratio 0.81, 95% confidence interval 0.67 to 0.98) and coronary revascularisation (0.89, 0.78 to 1.01) was lower in the vitamin D group, but there was no difference in the rate of stroke (0.99, 0.80 to 1.23).

CONCLUSIONS

Vitamin D supplementation might reduce the incidence of major cardiovascular events, although the absolute risk difference was small and the confidence interval was consistent with a null finding. These findings could prompt further evaluation of the role of vitamin D supplementation, particularly in people taking drugs for prevention or treatment of cardiovascular disease.

TRIAL REGISTRATION

ACTRN12613000743763.

Association between statin use and the risks of glaucoma in Australia: a 10-year cohort study

SYNOPSIS

In a cohort of middle-aged and elderly Australians, we found that long-term statin use was associated with a higher risk of glaucoma onset. As to subtypes of statins, the increased risk was only found in rosuvastatin users.

PURPOSE

To investigate the relationship between statin use and glaucoma onset in a 10-year longitudinal study.

METHODS

This nested case-control study was based on data from a large-scale cohort of Australians aged over 45 years old. Medication exposure was identified by claims records from the Pharmaceutical Benefits Scheme during the follow-up period (2009-2016). The onset of glaucoma was defined as the people with at least three claims of antiglaucoma medications. Controls matched by age, gender and cardiovascular diseases were selected from participants without prescription of antiglaucoma medications. A conditional logistic regression model was used to assess the association between statin use and glaucoma onset.

RESULTS

The proportion of statin users was higher in the case group (40.5%) than that in the control group (38.4%). After adjusting for baseline characteristics and longitudinal claims records, statin use was not associated with glaucoma onset (OR 1.04, 95% CI 0.97 to 1.11). However, an increased risk of glaucoma onset was observed in participants with a longer duration of statin use (>3 years vs <1 year: OR 1.12, 95% CI 1.04 to 1.21). With respect to specific types of statins, participants taking rosuvastatin were more likely to suffer from glaucoma (OR 1.11, 95%CI 1.01 to 1.22). The use of other statins was not significantly associated with glaucoma onset.

CONCLUSIONS

Long-term statin use was found to be associated with a higher risk of glaucoma onset in this study. Regarding specific types of statins, the increased risk of glaucoma onset was only observed in users of rosuvastatin.

Using electronic admission data to monitor temporal trends in local medication use: Experience from an Australian tertiary teaching hospital

Background and aims: Medication usage varies according to prescribing behavior, professional recommendations, and the introduction of new drugs. Local surveillance of medication usage may be useful for understanding and comparing prescribing practices by healthcare providers, particularly in countries such as Australia that are in the process of enhancing nationwide data linkage programs. We sought to investigate the utility of electronic hospital admission data to investigate local trends in medication use, to determine similarities and differences with other Australian studies, and to identify areas for targeted interventions.

Methods: We performed a retrospective longitudinal analysis using combined data from a hospital admissions administrative dataset from a large tertiary teaching hospital in Adelaide, South Australia and a hospital administrative database documenting medication usage matched for the same set of patients. All adult admissions over a 12-year period, between 1 January 2007 and 31st December 2018, were included in the study population. Medications were categorized into 21 pre-defined drug classes of interest according to the ATC code list 2021.

Results: Of the 692,522 total admissions, 300,498 (43.4%) had at least one recorded medication. The overall mean number of medications for patients that were medicated increased steadily from a mean (SD) of 5.93 (4.04) in 2007 to 7.21 (4.98) in 2018. Results varied considerably between age groups, with the older groups increasing more rapidly. Increased medication usage was partly due to increased case-complexity with the mean (SD) Charlson comorbidity index increasing from 0.97 (1.66) in 2007-to-2012 to 1.17 (1.72) in 2013-to-2018 for medicated patients. Of the 21 medication classes, 15 increased (p < 0.005), including antithrombotic agents; OR = 1.18 [1.16–1.21], proton pump inhibitors; OR = 1.14 [1.12–1.17], statins; OR = 1.12; [1.09–1.14], and renin-angiotensin system agents; OR = 1.06 [1.04–1.08], whilst 3 decreased (p < 0.005) including anti-inflammatory drugs (OR = 0.55; 99.5% CI = 0.53–0.58), cardiac glycosides (OR = 0.81; 99.5% CI = 0.78–0.86) and opioids (OR = 0.82; 99.5% CI = 0.79–0.83). The mean number of medications for all admissions increased between 2007 and 2011 and then declined until 2018 for each age group, except for the 18-to-35-year-olds.

Conclusion: Increased medication use occurred in most age groups between 2007 and 2011 before declining slightly even after accounting for increased comorbidity burden. The use of electronic hospital admission data can assist with monitoring local medication trends and the effects of initiatives to enhance the quality use of medicines in Australia.

The impact of sex on outcomes following carotid endarterectomy

BACKGROUND

Previous studies have demonstrated significant sex differences in vascular surgery outcomes. We assessed stroke or death rates following carotid endarterectomy (CEA) in women vs. men.

METHODS

The Vascular Quality Initiative (VQI) was used to identify all patients who underwent CEA between 2010-2019. Demographic, clinical, and procedural characteristics were recorded and differences between women vs. men were assessed using independent t-test and chi-square test. The primary outcomes were 30-day and 1-year stroke or death. Associations between sex and outcomes were assessed using univariate/multivariate logistic regression and Cox proportional hazards analysis.

RESULTS

52,137 women and 79,974 men underwent CEA in VQI sites during the study period. Women were younger (70.3 vs. 70.5 years, p < 0.001) and more likely to have hypertension (89.2% vs. 88.9%, p < 0.05) and diabetes (36.2% vs. 35.8%, p < 0.001), but less likely to be diagnosed with coronary artery disease (23.2% vs. 31.0%, p < 0.001). A greater proportion of men were receiving cardiovascular risk reduction medications and had symptomatic carotid stenosis (28.5% vs. 26.7%, p < 0.001). Women had shorter procedure times (113 vs. 122 minutes, p < 0.001) and were less likely to receive electroencephalography neuromonitoring (27.9% vs. 28.8%, p < 0.001), drain (35.9% vs. 37.3%, p < 0.001), and protamine (67.4% vs. 68.0%, p < 0.01). Stroke or death at 30 days (1.9% vs. 1.8%, p = 0.60) and 1 year (HR 0.98 [95% CI 0.94 - 1.01], p = 0.20) were similar between groups, which persisted in asymptomatic patients (HR 0.97 [95% CI 0.93 - 1.01], p = 0.17) and symptomatic patients (HR 0.99 [95% CI 0.93 - 1.05], p = 0.71). The similarities in 1-year stroke or death rates existed in both the US (HR 0.96 [95% CI 0.92 - 1.01], p = 0.09) and Canada (HR 1.21 [95% CI 0.47 - 3.11], p = 0.70).

CONCLUSIONS

Despite sex differences in clinical and procedural characteristics, women and men have similar 30-day and 1-year outcomes following carotid endarterectomy.

Drugs associated with cataract formation represent an unmet need in cataract research

Decreased light transmittance through the ocular lens, termed cataract, is a leading cause of low vision and blindness worldwide. Cataract causes significantly decreased quality of life, particularly in the elderly. Environmental risk factors, including aging, UV exposure, diabetes, smoking and some prescription drugs, are all contributors to cataract formation. In particular, drug-induced cataract represents a poorly-addressed source of cataract. To better understand the potential impact of prescription drugs on cataract, we analyzed publicly-available drug prescriptions data from the Australian Pharmaceutical Benefits Scheme. The data was analyzed for the 5-year period from July 2014 to June 2019. Analyses included the number of prescriptions for each drug, as well as the associated government and total prescription costs. The drugs chosen for analysis belonged to any of four broad categories—those with known, probable, possible or uncertain association with cataract in patients. The analyses revealed high prescription rates and costs for drugs in the Known category (e.g., steroids) and Possible category (e.g., psychotropic drugs). Collectively, these data provide valuable insights into specific prescription drugs that likely contribute to the increasing annual burden of new cataract cases. These data highlight the need—as well as new, stem cell-based opportunities—to elucidate molecular mechanisms of drug-induced cataract formation.

Statin Prescription Patterns and Associations with Subclinical Inflammation

Background and Objectives: Statins have been extensively utilised in atherosclerotic cardiovascular disease (ASCVD) prevention and can inhibit inflammation. However, the association between statin therapy, subclinical inflammation and associated health outcomes is poorly understood in the primary care setting. Materials and Methods: Primary care electronic health record (EHR) data from the electronic Practice-Based Research Network (ePBRN) from 2012−2019 was used to assess statin usage and adherence in South-Western Sydney (SWS), Australia. Independent determinants of elevated C-reactive protein (CRP) were determined. The relationship between baseline CRP levels and hospitalisation rates at 12 months was investigated. Results: The prevalence of lipid-lowering medications was 14.0% in all adults and 44.6% in the elderly (≥65 years). The prevalence increased from 2012 to 2019 despite a drop in statin use between 2013−2015. A total of 55% of individuals had good adherence (>80%). Hydrophilic statin use and higher intensity statin therapy were associated with elevated CRP levels. However, elevated CRP levels were not associated with all-cause or ASCVD hospitalisations after adjusting for confounders. Conclusions: The prevalence and adherence patterns associated with lipid-lowering medications highlighted the elevated ASCVD-related burden in the SWS population, especially when compared with the Australian general population. Patients in SWS may benefit from enhanced screening protocols, targeted health literacy and promotion campaigns, and timely incorporation of evidence into ASCVD clinical guidelines. This study, which used EHR data, did not support the use of CRP as an independent marker of future short-term hospitalisations.

Comparison of statins for primary prevention of cardiovascular disease and persistent physical disability in older adults

PURPOSE

Recent epidemiological evidence has suggested that use of lipid-lowering medications, particularly statins, was associated with reduced cardiovascular disease (CVD) events and persistent physical disability in healthy older adults. However, the comparative efficacy of different statins in this group remains unclear. This study aimed to compare different forms of statins in their associations with CVD and physical disability in healthy older adults.

METHODS

This post hoc analysis included data from 5981 participants aged ≥ 70 years (≥ 65 if US minorities; median age:74.0) followed for a median of 4.7 years, who had no prior CVD events or physical disability and reported using a statin at baseline. The incidence of the composite and components of major adverse cardiovascular events and persistent physical disability were compared across different statins according to their type, potency, and lipophilicity using multivariable Cox proportional-hazards models.

RESULTS

Atorvastatin was the most used statin type at baseline (37.9%), followed by simvastatin (29.6%), rosuvastatin (25.5%), and other statins (7.0%, predominantly pravastatin). In comparisons of specific statins according to type and lipophilicity (lipophilic vs. hydrophilic statin), observed differences in all outcomes were small and not statistically significant (all p values > 0.05). High-potency statin use (atorvastatin and rosuvastatin) was marginally associated with lower risk of fatal CVD events compared with low-/moderate-potency statin use (hazard ratio: 0.59; 95% confidence interval: 0.35, 1.00).

CONCLUSION

There were minimal differences in CVD outcomes and no significant difference in persistent physical disability between various forms of statins in healthy older adults. Future investigations are needed to confirm our results.

Symptom Status of Patients Undergoing Carotid Endarterectomy in Canada and United States

BACKGROUND

Previous studies have demonstrated significant geographic variations in the management of carotid artery stenosis despite standard guidelines. To further characterize these practice variations, we assessed differences in patient selection, operative technique, and outcomes for carotid endarterectomy (CEA) in Canada vs. United States.

METHODS

The Vascular Quality Initiative (VQI) was used to identify all patients who underwent CEA between 2010 and 2019 in Canada and United States. Demographic, clinical, and procedural characteristics were recorded and differences between countries were assessed using independent t-test and chi-square test. The primary outcome was the percentage of CEA performed for asymptomatic versus symptomatic disease. The secondary outcomes were 30-day and long-term stroke or death. Associations between country and outcomes were assessed using univariate/multivariate logistic regression and Cox proportional hazards analysis.

RESULTS

During the study period, 131,411 US patients and 701 Canadian patients underwent CEA in VQI sites. Patients from the US were older with more comorbidities including hypertension, diabetes, congestive heart failure, and chronic kidney disease. The use of a shunt, patch, drain, or protamine was less common in the US. Most patients had 70 - 99% stenosis, with no difference between regions. The percentage of CEA performed for asymptomatic disease was significantly higher in the US even after adjusting for demographic, clinical, and procedural characteristics (72.4% vs. 30.7%, adjusted OR 3.91 [95% CI 3.21 - 4.78], p < 0.001). Thirty-day stroke/death was low (1.8% vs. 1.9%) and 1-year stroke/death was similar between groups (HR 0.98 [95% CI 0.69 - 1.39], P = 0.89). The similarities in 1-year stroke/death persisted in asymptomatic patients (HR 0.70 [95% CI 0.37 - 1.30], P = 0.26) and symptomatic patients (HR 1.14 [95% CI 0.74 - 1.73], P = 0.56).

CONCLUSIONS

There are significant variations in CEA practice between Canada and US. In particular, most US patients are treated for asymptomatic disease, whereas most Canadian patients are treated for symptomatic disease. Furthermore, adjunctive procedures including shunting, patch use, and protamine administration are performed less commonly in the US. Despite these differences, perioperative and 1-year stroke/death rates are similar between countries. Future studies should investigate reasons for these variations and quality improvement projects are needed to standardize care.

Flavonoid-statin interactions causing myopathy and the possible significance of OATP transport, CYP450 metabolism and mevalonate synthesis

3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase inhibitors, statins, are a primary treatment for hyperlipidemic cardiovascular diseases which are a leading global cause of death. Statin therapy is life saving and discontinuation due to adverse events such as myotoxicity may lead to unfavourable outcomes. There is no known mechanism for statin-induced myotoxicity although it is theorized that it is due to inhibition of downstream products of the HMG-CoA pathway. It is known that drug-drug interactions with conventional medicines exacerbate the risk of statin-induced myotoxicity, though little attention has been paid to herb-drug interactions with complementary medicines. Flavonoids are a class of phytochemicals which can be purchased as high dose supplements. There is evidence that flavonoids can raise statin plasma levels, increasing the risk of statin-induced myopathy. This could be due to pharmacokinetic interactions involving hepatic cytochrome 450 (CYP450) metabolism and organic anion transporter (OATP) absorption. There is also the potential for flavonoids to directly and indirectly inhibit HMG-CoA reductase which could contraindicate statin-therapy. This review aims to discuss what is currently known about the potential for high dose flavonoids to interact with the hepatic CYP450 metabolism, OATP uptake of statins or their ability to interact with HMG-CoA reductase. Flavonoids of particular interest will be covered and the difficulties of examining herbal products will be discussed throughout.

Common systemic medications that every optometrist should know

Healthcare in the twenty-first century has witnessed an increased use of prescription drugs. As a member of a patient's health care team, optometrists should be aware of the pharmaceuticals taken by patients and their potential ocular complications. This paper will discuss the most prescribed medications in Australia today and their effects on the visual system. The paper will review the agents used to treat six common systemic conditions, their frequency of use, mechanism of action, clinical indications, and potential ocular manifestations. Literature has documented both positive and negative associations of systemic medications on the eye's health. Many associations documented here have shown conflicting evidence, thus warranting further investigation. Based on the frequency and severity of the ocular manifestations in the literature, recommendations for clinical care are given. Being familiar with the most common ocular side effects associated with common systemic medications aids in the correct and timely diagnosis of ocular complications to prevent permanent sequelae.

Efficacy and safety of statins in ethnic differences: a lesson for application in Indigenous Australian patient care

Although statins are effective in treating high cholesterol, adverse effects do occur with their use. Efficacy and tolerability vary among statins in different ethnic groups. Indigenous Australians have a high risk for cardiovascular and kidney diseases. Prescribing statins to Indigenous Australians with multi-morbidity requires different strategies to increase efficacy and reduce their toxicity. Previous studies have reported that Indigenous Australians are more susceptible to severe statin-induced myopathies. However, there is a lack of evidence in the underlying genetic factors in this population. This review aims to identify: inter-ethnic differences in the efficacy and safety of statins; major contributing factors accounting for any identified differences; and provide an overview of statin-induced adverse effects in Indigenous Australians.

Switching, Persistence and Adherence to Statin Therapy: a Retrospective Cohort Study Using the Australian National Pharmacy Data

BACKGROUND

Statins are widely prescribed for the primary and secondary prevention of cardiovascular disease (CVD), but their effectiveness is dependent on the level of adherence and persistence.

OBJECTIVES

This study aimed to explore the patterns of switching, adherence and persistence among the Australian general population with newly dispensed statins.

METHODS

A retrospective cohort study was conducted using a random sample of data from the Australian national prescription claims data. Switching, adherence to and persistence with statins were assessed for people starting statins from 1 January 2015 to 31 December 2019. Switching was defined as either switching to another intensity of statin, to another statin or to a non-statin agent. Non-persistence to treatment was defined as discontinuation (i.e. ≥90 days with no statin) of coverage. Adherence was measured using proportion of days covered (PDC), and patients with PDC < 0.80 were considered non-adherent. Cox proportional hazard models were used to compare discontinuation, switching and reinitiation between different statins.

RESULTS

A cohort of 141,062 people dispensed statins and followed over a median duration of 2.5 years were included. Of the cohort, 29.3% switched statin intensity, 28.4% switched statin type, 3.7% switched to ezetimibe and in 2.7%, ezetimibe was added as combination therapy during the study period. Overall, 58.8% discontinued statins based on the 90-day gap criteria, of whom 55.2% restarted. The proportion of people non-adherent was 24.0% at 6 months to 49.0% at 5 years. People on low and moderate intensity statins were more likely to discontinue compared to those on high-intensity statins (hazard ratio [HR] 1.20, 95% confidence interval [CI] 1.09-1.31), (HR 1.28, 95%CI 1.14-1.42), respectively. Compared to maintaining same statin type and intensity, switching statins, which includes up-titration (HR 0.77, 95%CI 0.70 to 0.86) was associated with less likelihood of discontinuation after reinitiation.

CONCLUSIONS

Long-term persistence and adherence to statins remains generally poor among Australians, which limits the effectiveness of these medicines and the consequent health impact they may provide for individuals (and by extension, the population impact when poor persistence and adherence is considered in the statin-taking population). Switching between statins is prevalent in one third of statin users, although any clinical benefit of the observed switching trend is unknown. This, combined with the high volume of statin prescriptions, highlights the need for better strategies to address poor persistence and adherence.

Trends in the Utilization of Lipid-Lowering Medications in Australia: An Analysis of National Pharmacy Claims Data

Lipid-lowering medications comprise standard of care in the prevention of cardiovascular disease. This study examined the trends in the utilization of statin and non-statin medications in the Australian general population between 2013 and 2019. Pharmacoepidemiological analyses were performed using pharmacy dispensing data from Australian Pharmaceutical Benefits Scheme. One-year prevalence and incidence of statin and non-statin prescribing patterns were reported, and relative variations in prescribing examined via Poisson regression modelling. The one-year prevalence of statins' prescriptions decreased between 2013-2019 by 5.5% (from 25.0%-19.5%). Females were less likely than males to be prescribed statins (rate ratio [RR]=0.90, 95% confidence interval [CI] 0.89-0.91). The one-year prevalence of ezetimibe alone, and in combination with statins, increased consistently from 2013-2019 from 1.5%-3.6% (P<0.01) and 0.1%-1.1% (P<0.01), respectively. The prevalence was higher among those aged 61-80 years (RR=1.20, 95%CI 1.10-1.21) and those aged older than 80 years (RR=1.34, 95%CI 1.22-1.47), when compared to people aged <60 years. The incidence of ezetimibe prescriptions was highest in people aged 61-80 years (RR=1.36, 95%CI 1.31-1.41) compared to those aged <60 years. The one-year prevalence of proprotein convertase subtilisin/kexin type 9 inhibitor prescriptions was highest among those aged 46-60 years (RR=1.24, 95%CI 0.97-4.97) compared to people aged <46 and >60 years. Females were less likely than males to be prescribed a proprotein convertase subtilisin/kexin type 9 inhibitor (RR=0.87, 95%CI 0.75-0.98). Statins remain the most prevalent lipid-lowering medication prescribed in Australia. The prescribing of non-statin medications remains low, but is increasing.

Statin use and discontinuation in Danes age 70 and older: a nationwide drug utilisation study

BACKGROUND AND OBJECTIVE

There is limited evidence on the clinical effects of statins in older persons. We aimed to explore statin use and discontinuation patterns in Danes age 70 and older.

DESIGN

Register-based drug utilisation study.

SETTING

Danish nationwide health registries.

SUBJECTS

All Danish persons aged ≥70 years between 2011 and 2016.

MEASUREMENTS

(1) Monthly prevalence and (2) quarterly incidence of statin use, (3) characteristics of new users, (4) total amount of statin redeemed, (5) statin discontinuation rate between 2014 and 2016 in long-term statin users and (6) factors associated with discontinuation.

RESULTS

We identified 395,279 unique older statin users between 2011 and 2016. The prevalence increased from 30% in 2011 to 33% in 2016 (23% for primary prevention and 56% for secondary prevention in 2016). The quarterly incidence fell from 11 per 1,000 persons in 2011 to 7 per 1,000 persons in 2016. The prevalence was generally stable in those 70 to 79 years. In those aged ≥80 years, the prevalence increased despite decreasing incidence. The proportion of persons initiating for primary prevention decreased from 58% in 2011 to 52% in 2016. Approximately 19% of long-term statin users discontinued therapy between 2014 and 2016. Increasing age was the strongest predictor of statin discontinuation.

CONCLUSIONS

Approximately one in three Danes age ≥ 70 years were taking statins in 2016. The characteristics of incident users shifted between 2011 and 2016, with less people age 80 and older starting on statins and fewer people starting for primary prevention.

Adherence, Persistence, and Switching Among People Prescribed Sodium Glucose Co-transporter 2 Inhibitors: A Nationwide Retrospective Cohort Study

INTRODUCTION

Non-adherence and non-persistence to diabetes medications are associated with worse clinical outcomes. In this study, we aimed to characterise the 1-year switching, adherence, and persistence patterns among people with diabetes aged 18 years and older prescribed sodium-glucose co-transporter 2 inhibitors (SGLT2is) in Australia.

METHODS

Using data from Australia's national Pharmaceutical Benefits Scheme (PBS), we identified 11,981 adults (mean age 60.9 years; 40.5% female) newly initiated on SGLT2is (5993 dapagliflozin; 5988 empagliflozin) from September 2015 to August 2017. Adherence was assessed via the proportion of days covered (PDC), persistence was defined as the continuous use of SGLT2i without a gap of ≥ 90 days, and switching was defined as the first change from dapagliflozin to empagliflozin or vice versa. Generalised linear models (GLMs) were used to compare the adherence (PDC = continuous), logistic regression models were used to compare the likelihoods of being adherent (PDC ≥ 0.80), and Cox proportional hazard models were used to compare the likelihoods of persistence and switching between people prescribed empagliflozin and dapagliflozin.

RESULTS

Overall, 65.8% (7879/11,981) of people dispensed SGLT2is were adherent (PDC ≥ 0.80) and 72.1% (8644/11,981) were persistent at 12 months. The mean PDC was 0.79 ± 0.27. The use of empagliflozin was associated with higher adherence (PDC = continuous) [odds ratio (OR) 1.04, 95% confidence interval (CI) 1.03-1.05], being adherent (OR 1.39, 95% CI 1.29-1.51), and persisting for 12 months [hazard ratio (HR) 1.14, 95% CI 1.06-1.22] compared with dapagliflozin. Only 4.3% (509/11,981) of people switched between the SGLT2i. Compared with dapagliflozin, people initiated on empagliflozin were less likely to switch [HR 0.46, 95% CI 0.38-0.55].

CONCLUSIONS

A considerable proportion of Australians prescribed SGLT2is were non-adherent or non-persistent. However, empagliflozin was associated with better adherence and persistence rates and a lower likelihood of switching compared with dapagliflozin.

Effectiveness of Statins as Primary Prevention in People With Gout: A Population-Based Cohort Study

BACKGROUND

Cardiovascular guidelines do not give firm recommendations on statin therapy in patients with gout because evidence is lacking.

AIM

To analyze the effectiveness of statin therapy in primary prevention of coronary heart disease (CHD), ischemic stroke (IS), and all-cause mortality in a population with gout.

METHODS

A retrospective cohort study (July 2006 to December 2017) based on Information System for the Development of Research in Primary Care (SIDIAP^Q), a research-quality database of electronic medical records, included primary care patients (aged 35-85 years) without previous cardiovascular disease (CVD). Participants were categorized as nonusers or new users of statins (defined as receiving statins for the first time during the study period). Index date was first statin invoicing for new users and randomly assigned to nonusers. The groups were compared for the incidence of CHD, IS, and all-cause mortality, using Cox proportional hazards modeling adjusted for propensity score.

RESULTS

Between July 2006 and December 2008, 8018 individuals were included; 736 (9.1%) were new users of statins. Median follow-up was 9.8 years. Crude incidence of CHD was 8.16 (95% confidence interval [CI]: 6.25-10.65) and 6.56 (95% CI: 5.85-7.36) events per 1000 person-years in new users and nonusers, respectively. Hazard ratios were 0.84 (95% CI: 0.60-1.19) for CHD, 0.68 (0.44-1.05) for IS, and 0.87 (0.67-1.12) for all-cause mortality. Hazard for diabetes was 1.27 (0.99-1.63).

CONCLUSIONS

Statin therapy was not associated with a clinically significant decrease in CHD. Despite higher risk of CVD in gout populations compared to general population, patients with gout from a primary prevention population with a low-to-intermediate incidence of CHD should be evaluated according to their cardiovascular risk assessment, lifestyle recommendations, and preferences, in line with recent European League Against Rheumatism recommendations.

Predictors of first-year nonadherence and discontinuation of statins among older adults: a retrospective cohort study

AIMS

The aim of this study was to examine the level of and predictors of statin nonadherence and discontinuation among older adults.

METHODS

Among 22 340 Australians aged ≥65 years who initiated statin therapy from January 2014 to December 2015, we estimated the first-year nonadherence (proportion of days covered [PDC] <0.80) and discontinuation (≥90 days without statin coverage) rates. Predictors of nonadherence and discontinuation were examined via multivariable logistic regression. Analyses were performed separately for general beneficiaries (with a higher co-payment; n = 4841) and concessional beneficiaries (with a lower co-payment; n = 17 499).

RESULTS

During the one-year follow-up, 55.1% were nonadherent (concessional 52.6%; general beneficiaries 64.2%) and 44.7% discontinued statins (concessional 43.1%; general beneficiaries 50.4%). Among concessional beneficiaries, those aged 75-84 years and ≥85 years were more likely to discontinue than people aged 65-74 years (odds ratio 1.11, 95% confidence interval 1.04-1.19 and 1.38, 1.23-1.54, respectively). Diabetes was associated with an increased likelihood of nonadherence and discontinuation, while hypertension, angina and congestive heart failure were associated with a lower likelihood of nonadherence and discontinuation. Anxiety was associated with an increased likelihood of discontinuation, but polypharmacy (concurrent use of five or more drugs) was associated with a lower likelihood of nonadherence and discontinuation. Statin initiation by a general medical practitioner was associated with both increased likelihood of nonadherence and discontinuation. Similar predictors of nonadherence and discontinuation were identified for the general beneficiaries.

CONCLUSIONS

Among older adults prescribed statins, first-year nonadherence and discontinuation are high. Specific population subgroups such as people aged ≥85 years, those with diabetes or anxiety may require additional attention to improve statin adherence.