A combined role of calcium channel blockers and angiotensin receptor blockers in stroke prevention

Long-Term Drug Therapy Following Carotid Endarterectomy Aimed at Reducing Major Adverse Cardiovascular Events

BACKGROUND

Timely carotid endarterectomy (CEA) reduces the risk of future stroke. This benefit is maximized with lifelong drug therapy aimed at reducing further major adverse cardiovascular events (MACEs), including stroke. Studies suggest that around half discontinue these drugs within 12 months. To assess if this is the case following CEA, we considered the MACE-reducing drugs prescribed several years later and compared this with the drugs they were prescribed at CEA.

METHODS

The electronic primary care records of 347 post-CEA patients a mean of 108 (range 43-185) months after surgery were interrogated. The prescriptions of generic MACE-reducing drugs (antithrombotic, lipid-lowering, antihypertension and diabetes) of the 187 alive were compared with their prescriptions at CEA and with the last prescription of the 160 who had died before the late review. The post-CEA incidence of further MACE in survivors was determined.

RESULTS

At late review, fewer of the post-CEA patients alive were taking antiplatelet drugs (143, 76% vs. 170, 91% P < 0.01), but more were fully anticoagulated (37v4 P < 0.01) when compared with prescriptions at CEA. Overall, there was no change in antithrombotic drug prescription rates (167, 89% vs. 172, 92%). Lipid-regulating drugs were well prescribed both at late review and at CEA (173, 93% vs. 169, 90%). The number prescribed antihypertension drugs was significantly higher at late review than at CEA (166, 89% vs. 67, 35% P < 0.01). The number treated for diabetes was similar (64, 34% vs. 42, 23%). There was no difference in the numbers of any of the MACE-reducing drugs prescribed between those who had survived to late review and those who had not. At late review, of those alive, there were 22 (12%) new strokes, and 24 (14%) had developed new or worsening ischemic cardiac symptoms.

CONCLUSIONS

We found a higher than expected prescription rate of MACE-reducing drugs many years after CEA. This finding may be due, in part, to the nationalized health service in the United Kingdom.

Role of phosphodiesterase 1 in the pathophysiology of diseases and potential therapeutic opportunities

Cyclic nucleotide phosphodiesterases (PDEs) are superfamily of enzymes that regulate the spatial and temporal relationship of second messenger signaling in the cellular system. Among the 11 different families of PDEs, phosphodiesterase 1 (PDE1) sub-family of enzymes hydrolyze both 3',5'-cyclic adenosine monophosphate (cAMP) and 3',5'-cyclic guanosine monophosphate (cGMP) in a mutually competitive manner. The catalytic activity of PDE1 is stimulated by their binding to Ca²⁺/calmodulin (CaM), resulting in the integration of Ca²⁺ and cyclic nucleotide-mediated signaling in various diseases. The PDE1 family includes three subtypes, PDE1A, PDE1B and PDE1C, which differ for their relative affinities for cAMP and cGMP. These isoforms are differentially expressed throughout the body, including the cardiovascular, central nervous system and other organs. Thus, PDE1 enzymes play a critical role in the pathophysiology of diseases through the fundamental regulation of cAMP and cGMP signaling. This comprehensive review provides the current research on PDE1 and its potential utility as a therapeutic target in diseases including the cardiovascular, pulmonary, metabolic, neurocognitive, renal, cancers and possibly others.

From hypertension to stroke: mechanisms and potential prevention strategies

Stroke is a major cause of disability and death worldwide. Prevention aimed at risk factors of stroke is the most effective strategy to curb the stroke pandemic. Hypertension is one of the most important risk factors for stroke. Despite the substantial evidence of the benefits of lowering blood pressure, conventional treatment does not normalize the burden of major cardiovascular events in patients with hypertension. Fully understanding the factors involved in the hypertension-induced stroke helps to develop new strategies for stroke prevention. Antihypertensive therapies selected should have positive blood pressure-independent effects on stroke risk. This review summarizes the factors involved in the hypertension-induced stroke, such as oxidative stress, inflammation, and arterial baroreflex dysfunction, and potential strategies for its prevention, therefore, provides clues for clinicians.

Adherence and persistence of single-pill ARB/CCB combination therapy compared to multiple-pill ARB/CCB regimens

OBJECTIVE

To evaluate the impact of angiotensin receptor blocker (ARBs)/dihydropyridine calcium channel blockers (CCBs) single-pill combination (SPC) on adherence to antihypertensive treatment in comparison to free combination of ARBs and CCBs.

RESEARCH DESIGN AND METHODS

A retrospective data analysis was performed using pharmacy claims data from a national pharmacy benefit management company. The study included patients who were newly initiated on ARB/CCB treatment between 01/01/2007 and 08/31/2008, aged ≥ 18 years, and continuously enrolled in the same health plan for 12 months prior to and 13 months after starting ARB/CCB treatment. Outcome variables were persistence, defined as time to discontinuation of therapy, and adherence, defined as proportion of days covered (PDC)  ≥ 0.80. Propensity score weighting was used to balance the characteristics of the two groups.

RESULTS

The final sample contained 2312 patients in the free-combination group and 2213 patients in the SPC group. Patients in the SPC group and the free-combination group were different in age, gender, type of insurance, history of antihypertensive therapy and co-morbidities. These differences were largely normalized after propensity score adjustment. Multivariate logistic model regression showed that patients in the SPC group had a 90% greater odds of being adherent to index therapy compared to patients in the free-combination group (odds ratio [OR] 1.90, 95% confidence interval [CI] 1.75-2.08, p< 0.001). A Cox proportional hazards model showed that patients in the SPC group were less likely to discontinue ARB/CCB SPC therapy compared to patients in the free-combination group (hazard ratio [HR] 0.66, 95% CI 0.63-0.70, p < 0.001). In both models, higher copayment (copayment $50 and above) was associated with worse persistence and adherence in comparison to patients who had a lower copayment ($0-$5): HR = 1.23, p < 0.001 and OR = 0.67, p < 0.001.

CONCLUSION

Patients using SPC ARB/CCB therapy were more likely to be persistent and adherent to treatment compared to patients taking free-combination therapy.