Grant: Summer Program in Aging

Extreme heatwaves in Canada are occurring more frequently and lasting longer. In 2021, a record heat event in British Columbia killed 619 people, most over age 60. Alberta's 2023 wildfires burned about 2.2 million hectares. These extremes are especially risky for the one in twelve Canadians living with heart disease, especially older adults who take several medicines that make heat harder to handle. Many heart medications can reduce the body's ability to stay safe in extremely hot or cold weather. Water pills can cause dehydration. Beta blockers can limit the heart's rate increase when overheated. Some medications reduce sweating or interfere with the body's ability to sense and respond to temperature changes. Doctors know that single medicines can increase the risk, but there is no simple way to calculate the total risk when a person takes several of these medicines at the same time. This matters because many older adults with heart disease use five to seven medicines. This project will create and test a Thermoregulatory Medication Burden Score. In simple terms, this score combines the effects of multiple medications on heat and cold tolerance. Using Alberta heart disease data linked to pharmacy records and local weather from 2004 to 2019, I will identify which drug combinations create the most vulnerability, develop a weighted score that reflects their combined effects, and test whether people with higher scores face more hospital visits during heat waves and cold snaps. I will also validate the score across diverse patient groups. By converting complex medication lists into a clear score, this project will enable clinicians and public health teams to target the right interventions at the right time. The goal is earlier counselling, safer medication plans, and faster support during alerts, so older Canadians with heart disease face less risk when extreme weather strikes.