• Hypertension is the single largest contributor to cardiovascular disease and death. While adequate control of hypertension reduces risk of disease, many patients have uncontrolled hypertension. This is often due to medication non-adherence. Left undetected, patients are prescribed additional medications, and referred to multiple specialists for investigations - leading to increased healthcare costs. Hence, detecting non-adherence to antihypertensive medications is important. However, patient history, patient recall, or questionnaires, are often inaccurate. Most recently, urine measurements of antihypertensive drug levels, using mass spectrometry, has been established as the gold standard to assess medication adherence. The one-time urine test for medication adherence is ideal: It's convenient, non-invasive, economical, and can be easily performed in a clinic setting. By improving blood pressure control, this will lead to reductions in healthcare visits, avoidance of catastrophic cardiovascular events. Ultimately, this translates to significant economic savings for both patients with hypertension and the healthcare system.
• Therefore, the investigators hypothesize that the implementation of urine adherence testing coupled with targeted counselling will improve the adherence and blood pressure control in hypertension. To do this, the investigators aim to (1) evaluate for medication adherence in 312 participants with recent stroke and hypertension; (2) evaluate for medication non-adherence in participants with uncontrolled hypertension; and (3) assess if detection of non-adherence can improve hypertension control.

• The investigators plan to achieve these aims in three steps. First, the investigators retrospectively assess medication adherence in 200 participants admitted for recent stroke using urine biospecimens collected. Second, the investigators will prospectively recruit 100 participants with poorly controlled hypertension and assess for medication adherence. Finally, participants detected with non-adherence will be counselled. These participants will be reassessed for improvements in both medication adherence and blood pressure.

Inclusion Criteria:

1. Age of 21 - 80 years
2. Systolic blood pressure of ≥140 mmHg or average systolic blood pressure ≥135 mmHg, or diastolic blood pressure ≥90 mmHg or average diastolic blood pressure ≥85 mmHg, on at least two measurements
3. Currently taking 2 or more hypertension medications
4. Able to provide informed consent.

Exclusion Criteria:

• Significant kidney impairment with eGFR of less than 45mL/min/1.73m2 or on dialysis
• Known history of chronic liver disease