The effects of ambient temperature variation on respiratory hospitalizations in summer,New York State

Abstract

Objective: A time-series study was used to assess the effect of temperature variation during summer on respiratory disease in New York State.

Methods: Daily respiratory admissions were linked with various meteorological indicators including daily and weekly temperature variation from June–August, 1991–2004. Two-stage Bayesian hierarchical models were used to first compute percent excess risks at the region level while controlling for air pollutants and time-varying variables using Poisson generalized additive models, and then to pool statewide estimates together after controlling for regional confounders.

Results: This study found that the daily temperature range between maximum and minimum temperature was associated with a 0·27–0·38% increased risk of admission. Minimum temperature (TMIN) above the previous 6-day average was associated with a 0·93% higher risk of respiratory morbidity. Multiday temperature ranges within 5 and 7 days were associated with 0·49 and 0·73% increases in admissions, respectively.

Conclusions: We concluded that daily and multiday temperature variation may increase respiratory hospitalizations with a larger risk associated with TMIN.     

广州市气象因素对手足口病发病的短期效应研究

有研究表明,手足口病在潮湿季节有病例增加的趋势[1].广州市近年来手足口病流行,并有夏秋季高发的特点[2].本研究使用分布滞后非线性模型(DLNM)探索气象对手足口病发病的影响[3].     

Does rain really cause pain? A systematic review of the associations between weather factors and severity of pain in people with rheumatoid arthritis

Objective: To examine the association between weather and pain in rheumatoid arthritis (RA). Methods: Systematic review of longitudinal observational studies (up to September 2009) with data on the association between weather variables and severity of pain in RA. The methodological quality was rated independently by the two authors according to an adapted Newcastle–Ottawa Scale. We analyzed the data on an aggregated (group) level with a meta‐analysis of correlations between pain and weather, and at an individual level as the proportion of patients for whom pain was significantly affected by the weather. Results: Nine studies were included. Many different weather variables have been studied, but only three (temperature, relative humidity and atmospheric pressure) have been studied extensively. Overall group level analyses show that associations between pain and these three variables are close to zero. Individual analyses from two studies indicate that pain reporting in a minority (<25%) of RA patients is influenced by temperature, relative humidity or atmospheric pressure. We were not able to relate the findings to methodological quality or other aspects of the studies. Conclusion: The studies to date do not show any consistent group effect of weather conditions on pain in people with RA. There is, however, evidence suggesting that pain in some individuals is more affected by the weather than in others, and that patients react in different ways to the weather. Thus, the hypothesis that weather changes might significantly influence pain reporting in clinical care and research in some patients with RA cannot be rejected.     

What measure of temperature is the best predictor of mortality?

Hot and cold temperatures significantly increase mortality rates around the world, but which measure of temperature is the best predictor of mortality is not known. We used mortality data from 107 US cities for the years 1987-2000 and examined the association between temperature and mortality using Poisson regression and modelled a non-linear temperature effect and a non-linear lag structure. We examined mean, minimum and maximum temperature with and without humidity, and apparent temperature and the Humidex. The best measure was defined as that with the minimum cross-validated residual. We found large differences in the best temperature measure between age groups, seasons and cities, and there was no one temperature measure that was superior to the others. The strong correlation between different measures of temperature means that, on average, they have the same predictive ability. The best temperature measure for new studies can be chosen based on practical concerns, such as choosing the measure with the least amount of missing data.     

Local daily temperatures,thermal seasons,and suicide rates in Finland from 1974 to 2010

Objectives

Suicide peaks in late spring and October are still seen in Finland among many countries. Weather factors have been suggested as explanations for these peaks, although with inconsistent results. Since the exact timing of these peaks varies each year, the length of daylight and changes in it seem inadequate as an explanation. We hypothesized that ambient temperature and the timing of thermal seasons might associate with suicide rate.

Methods

Suicide rates from three areas across Finland (N = 10,802) were analyzed with Poisson regression in six different models against variables calculated from the local ambient daily temperature, diurnal temperature range, and the duration from the onset of thermal seasons. Separate models for men and women were constructed.

Results

The temperature change over 5 days associated with the suicide rate of men in Helsinki region, or in other words, the lower the suicide rate was, the higher the temperature decrease had been. For women, the results were more inconsistent.

Conclusions

Our study is in line with some earlier studies which imply that impairment of thermoregulation might exist among suicide victims.     

Climatic influences on cardiovascular diseases

Classical risk factors only partially account for variations in cardiovascular disease incidence; therefore, also other so far unknown features, among which meteorological factors, may influence heart diseases (mainly coronary heart diseases, but also heart failure, arrhythmias, aortic dissection and stroke) rates. The most studied phenomenon is ambient temperature. The relation between mortality, as well as cardiovascular diseases incidence, and temperature appears graphically as a ‘‘U’’ shape. Exposure to cold, heat and heat waves is associated with an increased risk of acute coronary syndromes. Other climatic variables, such as humidity, atmospheric pressure, sunlight hours, wind strength and direction and rain/snow precipitations have been hypothesized as related to fatal and non-fatal cardiovascular diseases incidence. Main limitation of these studies is the unavailability of data on individual exposure to weather parameters. Effects of weather may vary depending on other factors, such as population disease profile and age structure. Climatic stress may increase direct and indirect risks to human health via different, complex pathophysiological pathways and exogenous and endogenous mechanisms. These data have attracted growing interest because of the recent earth’s climate change, with consequent increasing ambient temperatures and climatic fluctuations. This review evaluates the evidence base for cardiac health consequences of climate conditions, and it also explores potential further implications.     

湖北省洪涝灾区的气象因素与钩体病发病关系的研究

目的　探讨洪涝灾区的气象因素与钩端螺旋体病 (钩体病 )发病关系 ,控制洪涝灾区钩体病流行。方法选择仙桃市、枝江县作为调查点 ,调查 6～ 10月平均降雨量、年平均降雨量、6～ 10月平均气温、年平均气温和钩体病发病率。结果　仙桃市、枝江县 8月份钩体病发病数占总发病数的 75 .74% ,仙桃市 8月份降雨量与钩体病发病率呈显著性相关 ,相关系数为r =0 .72 (P <0 .0 1) ,其余因子与钩体发病率均无显著相关性。结论　仙桃市的钩体发病率与当地 8月份的降雨量有一定的相关性。