Effects of Blood Pressure Lowering With Different Antihypertensive Agents on Cognitive Function and Plasma Brain-derived Neurotrophic Factor Levels: A Comparative Study

Brain-Derived Neurotrophic Factor (BDNF) Concentration Levels in Cerebrospinal Fluid and Plasma in Patients With Glioblastoma: A Prospective, Observational, Controlled Study

Objective Glioblastomas (GBMs) are among the most frequent and most malignant of untreatable brain tumors. A GBM marker could accelerate diagnosis and facilitate therapeutic monitoring. This prospective, observational, controlled study compared brain-derived neurotrophic factor (BDNF) levels in cerebrospinal fluid (CSF) and plasma between patients with GBM and a control group. Materials and methods Patients in the observational group underwent elective GBM resection (n=24, 55.8%). Control patients (n=19, 44.2%) had elective brain surgery for an unrelated, non-neoplastic, non-traumatic pathology. We measured BDNF levels in tumors, CSF, and plasma with enzyme-linked immunosorbent assay (ELISA). Peripheral blood and CSF samples were collected before surgery, and tumors were sampled intraoperatively. We analyzed correlations between BDNF levels and patient sex, age, seizures, smoking, diabetes mellitus (DM), and the use of selected antiepileptic drug (AED) and antihypertensive drug groups. Results The mean CSF BDNF concentration was significantly lower in patients with GBM (6.5 pg/mL) than in controls (11.48 pg/mL) (p=0.002). Similarly, the mean plasma BDNF concentration was significantly lower in patients with GBM (288.59 pg/mL) than in controls (574.06 pg/mL) (p=0.0005). None of the examined factors influenced CSF, plasma, or tumor tissue BDNF concentrations (p>0.05). Conclusion Plasma and CSF BDNF levels were significantly lower in adults with GBM than in controls. Thus, CSF and plasma BDNF levels may aid in GBM diagnoses. Further prospective studies are required.

Adherence to Treatment, Arterial Stiffness and Cognitive Function in Irbesartan- Treated Newly Diagnosed Hypertensive Patients

OBJECTIVE

Non-adherence to antihypertensive agents leads to reduced blood pressure (BP) control. Data supporting the correlation of adherence with arterial stiffness (AS) are few. Furthermore, the causal relationship between AS and cognitive dysfunction (CO/DY) has not been clearly established. It is suggested that angiotensin II receptor blockers (ARBs) exhibit the lowest discontinuation rate among antihypertensive drugs.

DESIGN AND METHODS

We followed up with patients receiving monotherapy with irbesartan. CO/DY was assessed with the Mini-Mental State Examination (MΜSE) and other tests.

RESULTS

Patients [n=77; mean age: 56±11 years; 39 men (50.6%)] were followed-up for 16.1±10.9 months. At the end of follow up, significant reductions were observed in mean peripheral systolic BP (135±117 vs 153±11 mmHg; p<0.005), mean peripheral diastolic BP (85±11 vs 95±10 mmHg; p<0.005), mean central systolic BP (130±11 vs 142±12 mmHg; p<0.005) as well as in mean central diastolic BP (85±8 vs 95±97 mmHg; p<0.005). AS indices [carotid-femoral pulse wave velocity and augmentation index] also improved significantly: 7.7±1.4 vs 8.2±1.4 m/sec (p<0.005), and 29.1±8.3 vs 32.3±9.1 (p<0.005), respectively. At the end of the study, a significant improvement was observed in the MMSE test (29.7±0.7 vs. 29.2±0.9; p<0.02), as well as a significant reduction in 24h urine albumin (94±82 vs. 204±112 mg/24h, p<0.005). The level of adherence was high in 60/77 (77.9%), medium in 9/77 (11.6%) and low in 8/77 (10.38%) patients.

CONCLUSION

Hypertensive patients receiving mono-therapy with an ARB showed reduced AS, cognitive improvement, significant reductions in BP (peripheral and central) and decreased 24h urinary albumin excretion.

Drug interactions with dementia-related pathophysiological pathways worsen or prevent dementia

Many risk factors are known to induce or precipitate dementia. Drugs acting via different mechanisms can modulate cognitive performance and exert either beneficial or deleterious effects on cognition through functional or neuropathological mechanisms. This review discusses the association between several classes of drugs and cognitive impairment and dementia risk. These drugs can be divided into drugs targeting CNS disorders (e.g., anticholinergic drugs, antiepileptics, antipsychotics, benzodiazepines, and opioids) and drugs targeting non‐CNS disorders (e.g., antidiabetics, antihypertensives, proton pump inhibitors, and statins). Furthermore, we sought to highlight the pharmacological mechanisms underlying their possible detrimental or beneficial effects on cognition. Anticholinergic and antiepileptic drugs were excluded from this review because their effects on cognition are well known. Studies investigating benzodiazepines have revealed an increased risk of dementia. Conclusions on dementia risk or cognitive impairment regarding opioids and antipsychotic drugs are difficult to draw. These different classes appear to impair cognition not by a single clear mechanism of action specific to each class but by several relatively interdependent and interconnected mechanisms (e.g., impaired neurotransmission, neuroinflammation, neuronal death, oxidative stress, or interactions with dementia‐related pathways). The dementia risk initially associated with the use of proton pump inhibitors might have been overestimated. In contrast, statins, antihypertensive medications, and antidiabetics could potentially decrease the risk of dementia and cognitive impairment by acting in ways opposite to the mechanisms cited above.

Linked Articles

This article is part of a themed section on Therapeutics for Dementia and Alzheimer's Disease: New Directions for Precision Medicine. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.18/issuetoc