en عمومى General پژوهشي Research <div style="text-align: justify;"><span style="font-size:12pt"><span new="" roman="" style="font-family:" times=""><strong>Background</strong><strong>:</strong> Climate change and its consequences affect all aspects of human life, and with increasing of these consequences, short-term and long-term impacts are also intensified. One of the most important issues affected by climate change is public health. Tehran as a densely populated metropolis with a semi-arid climate; is located at the tip of the arrow is facing the risks caused by climate change.</span></span><br> <span style="font-size:12pt"><span new="" roman="" style="font-family:" times=""><strong>Materials and Methods:</strong> This study analyzed ERA5 reanalysis data (1988-2022), validated using statistical indices. Trends were evaluated with the non-parametric Mann-Kendall test. Warm Spell Duration Index (WSDI) and Cold Spell Duration Index (CSDI) assessed thermal waves. Correlation between temperature, hospital visits, and population (2014-2022) was also examined.</span></span><br> <span style="font-size:12pt"><span new="" roman="" style="font-family:" times=""><strong>Results:</strong> Tehran experienced a significant long-term temperature increase over 34 years, particularly in spring, winter, and July. Heatwave frequency increased, while cold waves decreased. Average temperatures during extreme events also rose. Temperature and hospital visits showed a 0.61 correlation. Population, hospital visits, and annual average temperature increased by 4.98%, 16.42%, and 2.11% respectively.</span></span><br> <span style="font-size:12pt"><span new="" roman="" style="font-family:" times=""><strong>Discussion:</strong> Hotter conditions and rising temperatures directly influence public health. The disproportionate growth in disease occurrence compared to population highlights the critical impact of extreme temperature events on hospital visit rates, emphasizing the escalating health burden from observed climate change.</span></span><br> <span style="font-size:12pt"><span new="" roman="" style="font-family:" times=""><strong>Conclusion:</strong> This research confirms a shift towards hotter conditions and a rising temperature trend in Tehran. The significant correlation between temperature and hospital visits, alongside disproportionate disease growth, strongly suggests that extreme temperature events and rising temperatures are key drivers for increased hospital visit.</span></span></div> Health, Global Warming, Climate Change, Heat Wave. 0 0 http://hdq.uswr.ac.ir/browse.php?a_code=A-10-642-1&slc_lang=en&sid=1 Aida Deyrmajaei aida.deyrmajaei@khu.ac.ir No Kharazmi University, Tehran, Iran. Mehry Akbary mehryakbary@khu.ac.ir Yes Kharazmi University, Tehran, Iran. Zahra Hejazizadeh hedjazizadeh@yahoo.com No Kharazmi University, Tehran, Iran. Mohammad Saligheh Salighe1338@gmail.com No Kharazmi University, Tehran, Iran.