Long-term persistence and adherence to blood pressure lowering agents among older Australians

Reinitiation and Subsequent Discontinuation of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers among New and Prevalent Users Aged 65 Years or More with Peripheral Arterial Disease

Angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin-receptor blockers (ARBs) are recommended in the treatment of arterial hypertension in patients with peripheral arterial disease (PAD). The aims of our study were: (a) to analyse the extent of reinitiation and subsequent discontinuation in older hypertensive PAD patients non-persistent with ACEIs/ARBs; (b) to determine patient and medication factors associated with reinitiation and subsequent discontinuation; and (c) to compare these factors between prevalent and new users. The analysis of reinitiation was performed on a sample of 1642 non-persistent patients aged ≥65 years with PAD newly diagnosed in 2012. Patients reinitiating ACEIs/ARBs were used for the analysis of subsequent discontinuation identified according to the treatment gap period of at least 6 months without any prescription of ACEI/ARB. In the group of non-persistent patients, 875 (53.3%) patients reinitiated ACEIs/ARBs during a follow-up (24.8 months on average). Within this group, subsequent discontinuation was identified in 414 (47.3%) patients. Being a new user was associated with subsequent discontinuation, but not with reinitiation. Myocardial infarction during non-persistence and after reinitiation was associated with reinitiation and lower likelihood of subsequent discontinuation, respectively. Being a prevalent or a new user is associated with the use of medication also after initial discontinuation.

A predictive model for identifying low medication adherence among older adults with hypertension: A classification and regression tree model

Various individual characteristics may affect medication adherence; however, few studies have investigated the effect of interrelationships among these various individual characteristics on medication adherence. This cross-sectional study explored the interrelationships among risk factors for medication adherence and established a predictive model of low medication adherence among older adults with hypertension. Convenience sampling was used to recruit 300 older adults with hypertension. The following parameters were recorded: demographic and disease characteristics, health beliefs, self-efficacy, social support, and medication adherence of antihypertensive drugs. Classification and regression tree (CART) analysis was performed to develop a predictive model of low medication adherence. The CART model revealed that health belief, disease duration, self-efficacy, and social support interacted to contribute to various pathways of low medication adherence. The predicted accuracy of the model was validated with a low misclassification rate of 26%. The proposed classification model can help identify risk cases with low medication adherence. Suitable health education programs based on these risk factors to manage and improve medication adherence for older adults with hypertension could be considered.

The extent of polypharmacy and use of 'fall risk increasing drugs' in the oldest old admitted to a regional New South Wales hospital

OBJECTIVE(S)

Polypharmacy is associated with significant morbidity including cognitive decline and falls. We sought to quantify the extent of polypharmacy and use of medications associated with fall risk in the very old admitted to a regional NSW hospital.

METHODS

Cross-sectional study of patients aged over 80 years admitted to a regional NSW hospital from September to October 2019. Demographic data and medication usage on admission were collected. Polypharmacy was defined as regular use of five or more medications.

RESULTS

A total of 401 patients were included: mean age was 87.2 (±4.6) years and 56.9% were female. Of the participations, 82.9% experienced polypharmacy, and the mean number of medications was 8.2 (±4.2). Of the patients, 91.6% utilised medications associated with risk of falls. There was no association between age and number of preadmission regular medications.

CONCLUSION

Polypharmacy is extremely common prior to acute hospitalisation for regional older individuals. This highlights the importance of medication rationalisation to reduce medication-related harm.

Dynamics of switching, adherence, and persistence of dipeptidyl peptidase-4 inhibitors use: A nationwide cohort study

AIMS

To characterise the patterns of switching, adherence, and persistence among adults aged ≥18 years with diabetes prescribed dipeptidyl peptidase-4 inhibitors (DPP-4is) in Australia.

METHODS

The analysis included 15,915 adults newly prescribed DPP-4is (sitagliptin = 9576; vildagliptin = 1130; saxagliptin = 1126; linagliptin = 3560; and alogliptin = 523). Multivariable logistic regression model was used to compare the non-adherence (proportion of days covered [PDC] <0.80) rates whereas Cox proportional hazards regression models were used to compare switching and non-persistence (≥90-day gap) among different DPP4-is over 12-months.

RESULTS

Overall, 36.0% (5722/15,915) of DPP-4i users were non-adherent and 30.0% (4775/15,915) were non-persistent at 12-months. Compared to sitagliptin, vildagliptin, linagliptin, and alogliptin were not associated with higher non-adherence and non-persistence. However, saxagliptin was associated with a higher likelihood of being non-adherent (odds ratio 1.41, 95% confidence interval [CI] 1.23-1.60) or non-persistent (hazard ratio 1.27, 95% CI 1.15-1.42) compared to sitagliptin. Just 3.2% of people switched between different DPP-4is. Compared to sitagliptin, people initiated on vildagliptin, saxagliptin, alogliptin, and linagliptin were more likely to switch.

CONCLUSIONS

We found no significant differences in the adherence and persistence rates between alogliptin, vildagliptin or linagliptin and sitagliptin. However, saxagliptin was associated with higher non-adherence and non-persistence compared to sitagliptin. Switching was lowest amongst users of sitagliptin.

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.