Clinical Pharmacology of Antihypertensive Therapy

Association of Thiazide Use in Patients with Hypertension with Overall Fracture Risk: A Population-Based Cohort Study

Thiazide diuretics have long been widely used as antihypertensive agents. In addition to reducing blood pressure, thiazides also control calcium homeostasis and increase bone density. We hypothesized that the use of thiazides in patients with hypertension would reduce overall fracture risk. We used the Taiwan National Health Insurance Research Database to find patients with a hypertension diagnosis who accepted antihypertensive treatment from 2000 to 2017. The patients were further classified into thiazide users and nonthiazide users. Multivariable Cox regression analysis and Kaplan-Meier survival analysis were performed to estimate the adjusted hazard ratios (aHRs) and cumulative probability of fractures. After 1:1 propensity score matching by sex, age, urbanization level of place of residence, income, comorbidities, and medications, there were 18,483 paired thiazide users and non-users, respectively. The incidence densities of fractures (per 1000 person-months) were 1.82 (95% CI: 1.76-1.89) and 1.99 (95% CI: 1.92-2.06) in the thiazide and nonthiazide groups, respectively. The results indicated a lower hazard ratio for fractures in thiazide users (aHR = 0.93, 95% CI: 0.88-0.98). Kaplan-Meier survival analysis revealed a significantly lower cumulative incidence of fractures in the thiazide group (log-rank test; p = 0.0012). In conclusion, our results reveal that thiazide use can reduce fracture risk. When antihypertensive agents are being considered, thiazide may be a better choice if the patient is at heightened risk of fracture.

Perindopril increases the swallowing reflex by inhibiting substance P degradation and tyrosine hydroxylase activation in a rat model of dysphagia

Patients with hypertension have a high risk of ischemic stroke and subsequent stroke-associated pneumonia. Stroke-associated pneumonia is most likely to develop in patients with dysphagia. The present study was designed to compare the ameliorative effects of different treatments in rat model of dysphagia. Spontaneously hypertensive rats were treated with bilateral common carotid artery occlusion (BCAO) to induce chronic cerebral hypoperfusion causing disorders of the swallowing reflex. Angiotensin-converting enzyme (ACE) inhibitors (perindopril, imidapril and enalapril), an angiotensin II type 1-receptor blocker (losartan), a vasodilator (hydralazine) and an indirect dopamine agonist (amantadine) were dissolved in drinking water and administered to the rats for six weeks. The blood pressure, the swallowing reflex under anesthesia, the substance P content in the striatum and the tyrosine hydroxylase (TH) expression in the substantial nigra were measured. Compared to the vehicle control, the decrease in the swallowing reflex induced by BCAO was attenuated significantly by enalapril, imidapril and perindopril, but only slightly by losartan. Hydralazine had no effect on the swallowing reflex. Amantadine significantly attenuated the decreased swallowing reflex but increased the blood pressure. Cerebral hypoperfusion for six weeks decreased the TH expression and substance P level. Perindopril improved both the TH expressions and substance P level, but imidapril, enalapril and amantadine only improved the substance P level. The present findings indicate that perindopril could be useful for preventing dysphagia in the chronic stage of stroke by attenuating the decrease in TH expression and the decrease in the substance P level.