Research Question: What is the combined effect of temperature (including both heat and cold) and air pollution on hospitalization and mortality among individuals with diabetes?
Objective 1: Assess the impact of heat and cold on diabetes-related health outcomes
Rationale: People with diabetes are particularly vulnerable to temperature extremes due to impaired thermoregulation. Diabetes is often comorbid with cardiorespiratory conditions which are also sensitive to extreme temperature. However, few studies have examined how heat and cold affect health outcomes among people with diabetes, particularly those with comorbid conditions.
Objective 2: Evaluate the synergistic effects of temperature and air pollution
Rationale: Air pollution (ozone and particulate matter) may exacerbate heat- and cold-related health impacts. Most studies treat air pollutants as confounders, with few examining their interaction with temperature. Some report heightened risks of cardiorespiratory and diabetes-related hospitalizations, but the synergistic effects of temperature and air pollution on these outcomes in people with diabetes remain largely unexplored, particularly for those with comorbid conditions.
Objective 3: Identify individual-level risk factors for heat and cold vulnerability
Rationale: Existing research primarily relies on semi-ecological designs using administrative data, often highlighting the role of advanced age. However, the lack of granular cohort data results in an oversight of individual level characteristics that shape vulnerability to temperature exposure, such as medication use, diet, and behavioral factors.
Objective 4: Explore the temporal trends of heat-related and cold-related risk
Rationale: It is unclear whether population-level resilience to heat and cold has improved over time among people with diabetes. Longitudinal evidence is needed to understand how this population is adapting to climate change.