Diurnal Temperature Range and Daily Cardiovascular Mortalities Among the Elderly in Hong Kong

ABSTRACT

The authors aimed to examine the association between diurnal temperature range (DTR) and daily mortalities due to cardiovascular disease among people aged 65 years and older in Hong Kong, China. The authors used a generalized additive model to regress daily mortalities of the elderly due to cardiovascular disease on DTR and daily concentrations of air pollutants from 1997 to 2002. They also tested the effects of different lag days of DTR on mortality. Results indicate significant associations between cardiovascular mortality and DTR at lag day 1 and at lag days 0–1 to 0–5. The largest effect was at lag days 0–3 (relative risks = 1.017; 95% confidence interval = 1.003–1.031). The authors recommend that special attention be paid to the elderly population to protect them from excessive diurnal variations in temperature.

KEYWORDS:

• cardiovascular diseases
• diurnal temperature range
• elderly
• Hong Kong
• mortality

Notes

^aFor single lag days, DTR lag day 0 implies DTR on the same day as the day cardiovascular mortality occurs, while lag day n implies the nth day before the day of death; Cumulative lag days 0–2 of DTR denotes the average of DTR on the same day, 1 day before, and 2 days before death occurs.

*p-value < 0.05.

**p-value < 0.01.