RESUMEN
Objectives: The environmental effect in heart failure (HF) patients is well established. However, the data is limited from low-to middle-income countries like India. This study determined the impact of environment on acute decompensated HF (ADHF) admissions and mortality in India. Methods: Retrospectively, the data of all HF patients admitted between April 2017 and March 2019 was accessed through electronic hospital records. Simultaneously, the environmental-related data was collected from the central pollution control board. Results: The study included 4561 patients of ADHF. The peak of monthly ADHF events (admission and mortality) was observed during the chilly month (January) while the lowest rates were observed in summer months (MayeJune). The most significant factor correlating inversely with the monthly ADHF admission (r ¼ 0.78, p ¼ 0.003) and mortality (r ¼ 0.65, p ¼ 0.004) was the maximum air temperature, and it was found to be the independent predictor for both ADHF mortality [t ¼ 2.78, b ¼ 0.84; 95%CI(-6.0 to 0.6), p ¼ 0.021] and admission [t ¼ 4.83, b ¼ 0.91; 95%CI(-19.8 to 6.9), p ¼ 0.001]. The above correlation was better seen in the elderly subset and male gender. Humidity and the air pollution attributes did not have a significant correlation with ADHF admission or mortality. Conclusion: In conclusion, even in low-to middle-income country like India, a periodic effect of season was demonstrated for ADHF mortality and admission, with a peak in ADHF events noted during winter months especially in the regions having extremes of seasons. Air pollution could not affect the ADHF outcome for which further studies are needed
RESUMEN
Background: Psoralen with ultraviolet A is an effective photochemotherapeutic modality. A subtype of this, PUVAsol, uses sunlight as the natural source of ultraviolet A. The amount of sunlight received and the consequent ultraviolet A exposure vary according to the month in the year, time of the day and geographical location of a place. Aim: The aim of this study is to determine irradiance of ultraviolet A in ambient sunlight and optimum exposure time for PUVAsol. Materials and Methods: This was an observational study carried out at Postgraduate Institute of Medical Education and Research, Chandigarh (30.7333°N, 76.7794°E), India using a photometer. Ultraviolet A irradiance was recorded at a fixed place at 10 AM, once weekly for a period of 12 months. Results: The irradiance of peak ultraviolet A was found to be 3.1 mW/cm2 in June 2016 while irradiance of 0.64 mW/cm2 was recorded in January 2017. The exposure time needed for therapeutic dose of 2 J/cm2 was 11 min 6 s in June 2016 while exposure time for achieving therapeutic dose of 2 J/cm2 was 52 min 5 s in January 2017. The duration of exposure was found to be significantly longer in the winter months. Limitation: The limitation of the study is not determining ultraviolet B radiation and infrared exposure. Other limitation of this study is that the irradiance was measured only at 10 am. This data cannot be used to determine irradiance at different time points in the day as the patient may expose himself/herself to sunlight anytime depending on his/her convenience. Conclusions: The study demonstrates the mean exposure time required for a given therapeutic dose of ultraviolet A in different months. The wide variation in ultraviolet A irradiance in natural sunlight over the year in different months also suggests that exposure times for PUVAsol should be based on the season and geographical location at the site of therapy and not based on uniform guidelines.