Trends in heating fuel costs and cold weather-related hospitalizations in New York State, 1991-2009

Heating fuel costs may affect public health if susceptible populations are unable to afford adequate warmth in their residence. An ecologic correlation analysis was conducted to assess the relationship between residential heating fuel costs and hospitalizations for cold weather exposures which occurred at home in New York State during the heating seasons between November 1991 and March 2009. Total hospitalization counts, average heating oil and natural gas costs, and total heating degree days were calculated for each heating season, defined as November 1 through March 30. Total heating degree days showed a slightly decreasing trend over the study period. Home heating oil costs were relatively flat, near $1.00/gal from 1991 through 1999, but increased during the next decade to peak at over $3.00/gal before decreasing slightly in the 2008-2009 heating season. Natural gas costs also increased over the study from below $8.00/thousand cubic feet in 1991-1992 to over $16.00/thousand cubic feet in 2008-2009. Starting in 1999, the increases in heating fuel costs began to outpace increases in Per Capita Income (PCI). Since 2004, the percentage increases in heating oil and natural gas costs have been consistently higher than increases in both PCI and the Consumer Price Index (CPI for all goods) relative to 1991 costs. There was a statistically significant increase in average total hospitalizations (p=0.02) in the heating seasons after mid-1999 when compared to heating seasons before mid-1999. Crude risk ratios estimated an increase in log count hospitalizations for each dollar increase in the cost of heating oil, RR=1.30 (1.20, 1.40) and natural gas, RR=1.09 (1.06, 1.12) after controlling for heating degree days.

The primary finding showed a positive correlation between fuel costs and cold-weather related hospitalizations, after controlling for heating degree days. The study population was older and came from ZIP codes with lower average median household incomes than the overall population of New York. However, to the extent that this may have implications for heating assistance programs and other health policy development, further work would need to be done to better measure cold weather-related illnesses and home heating costs, as well as other potentially-related factors.