Hamid Sharif Nia
1, Yiong Huak Chan
2, Erika Sivarajan Froelicher
3, Saeed Pahlevan Sharif
4, Ameneh Yaghoobzadeh
5, Azar Jafari
6, Amir Hossein Goudarzian
7*, Roghiyeh Pourkia
8, Ali Akbar Haghdoost
9, Farhad Arefinia
10, Roghieh Nazari
11 Department of Medical-Surgical Nursing, School of Nursing and Midwifery Amol, Mazandaran University of Medical Sciences, Sari, Iran
2 Biostatistics Unit, Yong Loo Lin School of Medicine, National University Health System, Singapore
3 Department of Physiological Nursing, Department of Epidemiology & Biostatistics, University of California San Francisco, California, USA
4 Taylor’s Business School, Taylor’s University Malaysia, Subang Jaya, Malaysia
5 Department of Nursing, Tehran University of Medical Sciences, Tehran, Iran
6 Department of Nursing, Mazandaran University of Medical Sciences, Sari, Iran
7 Faculty of Nursing, Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
8 Department of Cardiology, Cardiovascular Research Center, Babol University of Medical Sciences, Babol, Iran
9 Modeling in Health Research Center, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran
10 School of Nursing and Midwifery Amol, Mazandaran University of Medical Sciences, Sari, Iran
Abstract
Background: Meteorological parameters and seasonal changes can play an important role in the occurrence of acute coronary syndrome (ACS). However, there is almost no evidence on a national level to suggest the associations between these variables and ACS in Iran. We aim to identify the meteorological parameters and seasonal changes in relationship to ACS. Methods: This retrospective cross-sectional study was conducted between 03/19/2015 to 03/18/2016 and used documents and records of patients with ACS in Mazandaran ProvinceHeart Center, Iran. The following definitive diagnostic criteria for ACS were used: (1) existence of cardiac enzymes (CK or CK-MB) above the normal range; (2) Greater than 1 mm ST-segment elevation or depression; (3) abnormal Q waves; and (4) manifestation of troponin enzyme in the blood. Data were collected daily, such as temperature (Celsius) changes, wind speed and its direction, rainfall, daily evaporation rate; number of sunny days, and relative humidity were provided by the Meteorological Organization of Iran. Results: A sample of 2,054 patients with ACS were recruited. The results indicated the highest ACS events from March to May. Generally, wind speed (18 PM) [IRR = 1.051 (95% CI: 1.019 to1.083), P=0.001], daily evaporation [IRR = 1.039 (95% CI: 1.003 to 1.077), P=0.032], daily maximum (P<0.001) and minimum (P=0.003) relative humidity was positively correlated withACS events. Also, negatively correlated variables were daily relative humidity (18 PM) [IRR =0.985 (95% CI: 0.978 to 0.992), P<0.001], and daily minimum temperature [IRR = 0.942 (95%CI: 0.927 to 0.958), P<0.001]. Conclusion: Climate changes were found to be significantly associated with ACS; especially from cold weather to hot weather in March, April and May. Further research is needed to fully understand the specific conditions and cold exposures.