The role of meteorologic factors and air pollution on the frequency of pediatric epistaxis

The role of meteorologic factors and air pollution on the frequency of pediatric epistaxis

M. Volkan Akdoğan, MD; Evren Hızal, MD; Mustafa Semiz, PhD; Özgül Topal, MD;Hakan Akkaş, MD; Aydın Kabataş, MSc; Selim S. Erbek, MD

Abstract

Fluctuations in atmospheric temperature, humidity,and air pollution are associated with the incidenceof epistaxis. To date, no study in the literature hasevaluated the effect of air pollution and meteorologicconditions on the pediatric population. We aimed toevaluate the effect of meteorologic factors and air pollu-tion on the frequency of epistaxis in children. Childrenpresenting to an outpatient clinical setting at a tertiarycare hospital during a 5-year period (July 1, 2009, toJune 30, 2014) and diagnosed with epistaxis formedthe study population. Daily temperature and humidityparameters and average daily atmospheric water va-por pressure, average daily concentration of particulatematter <10 µm in diameter, and sulfur dioxide read-ings were obtained. The distribution of daily parame-ters was analyzed. Of the 1,559 children with the pri-mary diagnosis of epistaxis, data from 1,330 childrenwere analyzed after excluding patients with coexistingpathologies. Positive correlations were found betweenthe frequency of epistaxis and both the average dailytemperature and the difference between the maximumand minimum daily temperature. There was a negativecorrelation between the epistaxis frequency and the av-erage daily humidity, the difference between the maxi-mum and minimum daily humidity, the average dailyconcentration of particulate matter, and the sulfur di-oxide levels. Our findings suggest that epistaxis in chil-dren is related to high temperatures and low humidity.

IntroductionEpistaxis is common in children. Thirty percent ofchildren younger than 5 years, 56% of those 6 to 10years old, and 64% aged 11 to 15 years have at least onenosebleed attack.1Epistaxis is classified as anterior or posterior basedon the primary bleeding site. Most childhood epistaxisis spontaneous anterior and self-limiting in nature.2 Inmost children, epistaxis originates from the Little area,which is located at the anterior region of the nasal sep-tum, where several terminal vessels anastomose witheach other forming a plexus (Kiesselbach plexus) underthe nasal mucosa.3Atmospheric conditions may be linked with the ratesof epistaxis. Fluctuations in temperature and humidityare associated with nasal mucosal changes in the Littlearea and are known to affect the incidence of epistax-is.3,4 Most studies in the literature suggest that epistaxisoccurs more frequently in the winter months becauseof an increased prevalence of upper respiratory tractinfections and mucosal dryness caused by low humidity.Low atmospheric temperature has been linked withincreased rates of epistaxis in some recent studies,4-11whereas other reports suggest a relationship with hightemperature.12,13 Bray et al reported no meteorologicfactors or seasonal preponderance of epistaxis.14Patient groups in these previous studies consistedof adult or mixed populations of adult and pediatricpatients. Epistaxis in adults, however, is considered adifferent condition than epistaxis in children, with anti-coagulant use and hypertension being common factorsin adults. Further, posterior epistaxis is more commonin adults than in children.15Air pollution has significant negative effects on health.Exposure to high concentrations of pollutants may re-sult in an increased frequency of epistaxis. Only a fewstudies in the literature have investigated the effect ofatmospheric pollutant concentrations on the frequencyof epistaxis.16,17 Air pollution shows seasonal variationsand is associated with meteorologic factors. The effect of air pollution on rates of epistaxis may be due to a directeffect of pollutants on the nasal mucosa or a secondaryeffect that is mediated by other factors such as an increasein blood pressure.16To our knowledge, no study in the literature hasevaluated the effect of air pollution and meteorologicconditions on the incidence of epistaxis in the pediatricpopulation. Thus, we aimed to evaluate the effect of me-teorologic conditions and air pollution on the frequencyof epistaxis in children Patients and methodsEthical considerations. This study was approved byBaskent University Institutional Review Board (Proj-ect no: KA 15/240) and supported by Baskent Univer-sity Research Fund.Study design. The patient files of children <16 yearsold who were seen in an outpatient clinic setting ata tertiary care hospital during a 5-year period (July1, 2009, to June 30, 2014) and diagnosed as epistaxiswith the R04.0 code according to The InternationalClassification of Diseases, 10th Revision (ICD-10), wereretrospectively reviewed.R04.0 was the primary diagnosis code for all patients.Cases of postoperative epistaxis and patients with majornasal trauma, intranasal mass, or foreign body were ex-cluded. In addition, patients who had a bleeding disorder,systemic disease such as hepatic or renal insufficiency,hereditary hemorrhagic telangiectasia, and those whohad a history of anticoagulant or antiplatelet drug usewere excluded from the study.The meteorologic data were provided by the TurkishState Meteorological Service. Air pollution parameterswere obtained from the Konya Metropolitan Munic-ipality website (http://www.konya.bel.tr/havakalitesi.php). Average daily temperature (TAV)(0C), daily max-imum (TMAX) and minimum (TMIN) temperature (0C),the difference between the maximum and minimum daily temperature (TDIF)(0C), average dai-ly relative humidity (HUMAV)(%), dailymaximum (HUMMAX) and minimum(HUMMIN) humidity (%), the differencebetween the maximum and minimumdaily relative humidity (HUMDIF)(%),average daily atmospheric pressure (PATM)(hPa), average daily atmospheric watervapor pressure (PWV)(hPa), average dailyconcentration of particulate matter <10µm in diameter (PM10)(µm/m3), and sul-fur dioxide (SO2)(µm/m3) readings wereobtained for 1,826 days (between July 1,2009, and June 30, 2014).Seasonal and monthly distributionsof daily parameters were analyzed. For seasonal distribution, each year was divided into fourconventional seasons as summer (June 1 to August31), autumn (September 1 to November 30), winter(December 1 to February 28/29), and spring (March1 to May 31).Statistical analysis. All analyses were performedusing the Statistical Package for the Social Sciences forWindows version 15.0. Mean and standard deviationwere used for continuous variables and frequency, andpercentages were used for categorical variables explain-ing descriptive statistics. The K-dependent Friedmantest was used for monthly and seasonal comparison ofparameters. The Pearson correlation coefficient wasused for detecting the relationship between parameters,and the Spearman correlation coefficient was usedfor detecting the relationship between the SO2 levelsand other parameters. For graphics, all values werenormalized and standardized. A p value of <0.05 wasconsidered statistically significant. ResultsA total of 1,559 patients had a primary diagnosis of ep-istaxis. After patients with coexisting pathologies wereexcluded, 1,330 subjects remained. The mean age ofthe patients was 92.5 ± 44.62 months (range: 9 to 192months). A total of 782 patients (58.8%) were boys and548 (41.2%) were girls.Standardized and normalized frequency of cases andmonthly temperature parameters during the 5-year studyperiod are shown in figure 1. July had the highest dailyadmission frequency (1.45/day) followed by August(1.28/day), September (0.99/day), and June (0.96/day).Lowest daily admission frequency was obtained inNovember (0.47/day), February (0.45/day), December(0.4/day), and January (0.38/day).The coldest month of the year was January, with amean daily temperature of 2.56°C, followed by December(3.67°C), February (4.12°C), and March (7.8°C). The hottest month was July, with a mean daily temperatureof 25.39°C, followed by August (24.52°C), June (21.5°C),and September (20.34°C).Lowest monthly relative humidity was in August(33.13%), followed by July (35.87%), September(39.48%), and June (46.87%). The presentation rates werealso highest in these months. Relative humidity was thehighest in January (78.19%), December (75%), Novem-ber (68.19%), and February (65.51%). The relationshipbetween the humidity parameters and presentation ratesis shown in figure 2.The standardized values of atmospheric pressure andwater vapor pressure parameters and frequency of epi-staxis are shown in figure 3. Atmospheric pressure washigher in winter months, whereas water vapor pressurewas higher in summer months.Air pollution values were higher for the winter andlower for the summer months. The relationship between the air pollution parameters and frequencyof epistaxis is shown in figure 4.A positive correlation was observedbetween the frequency of epistaxis andboth the average daily temperature andthe difference between the maximum andminimum daily temperature. The correla-tion was negative between the epistaxisfrequency and the average daily humidity,the difference between the maximum andminimum daily humidity, PM10, and SO2levels (p < 0.05).When the mean daily temperature wasdivided into 10°C bands and average dailyrelative humidity was divided into 20%bands, the frequency of epistaxis was foundto increase with low humidity and hightemperature (figures 5 and 6). In terms of all variables calculated, statistical analysisrevealed a significant difference in epistaxisfrequency between the seasons (p < 0.01),with the incidence being highest in sum-mer and lowest in winter. In the summerseason, the average daily temperature andthe difference between the maximum andminimum temperature was the highest,and the daily humidity and the differencebetween the maximum and minimumhumidity was lowest. DiscussionEpistaxis appears to have a bimodal agedistribution. The peak ages of incidenceare <18 years and >50 years. Nosebleedstend to be more severe in the older popu-lation, whereas those in children and ad-olescents are more often minor and self-limited.18In adults, various underlying conditions such asallergic rhinitis, chronic sinusitis, coagulopathy, al-cohol abuse, substance abuse, antihemostatic agentuse (anticoagulant and/or antiplatelet medications),renal diseases, hereditary hemorrhagic telengiectasia,hematologic malignancies, and cardiovascular diseasesincluding hypertension and congestive heart failure areassociated with the incidence of epistaxis.4,18 Meteoro-logic factors and air pollution may not only affect theincidence of epistaxis but also are associated with at leastsome of those comorbidities such as hypertension.19,20The incidence of the comorbidities that are associatedwith epistaxis also increases with age. Thus, it is difficultto distinguish the real effect of atmospheric conditionson epistaxis in a population that consists of both childrenand adults. Etiologic factors in pediatric epistaxis arenot clearly understood. To our knowledge, the effect of atmospheric conditions and air pollution on childhoodepistaxis has not been adequately studied.In our study, we analyzed all patients presentingwith epistaxis and excluded patients with coexistingpathologies. Our study population consisted exclusivelyof pediatric patients. Epistaxis is often bothersome andalarming for both parents and children so that parentsmay be more sensitive in seeking medical care, andtherefore the presentation rates may differ from thoseof adults. Childhood may be the more appropriate time to inves-tigate the effect of atmospheric conditions on epistaxis,since most of the coexisting risk factors for epistaxisin adults that may also be affected by atmosphericconditions do not exist in children. Moreover, childrenare physiologically and metabolically less effective atadapting to changes in ambient humidity and otherweather-related exposures and are more sensitive toclimate changes compared with adults..21Results of the studies in the literature have shownvariable effects of climatic conditions on the frequencyof epistaxis. Sowerby et al found a negative correlationbetween the rate of epistaxis and temperature and nocorrelation between the epistaxis rate and humidityin a cold climate.5 Muhammad et al found that lowtemperature and humidity increase the incidence ofepistaxis in a climate that has mostly rainy seasons. 6 In a climate similar to that of our region, Kemal and Sendetermined a positive correlation between the rates of epi-staxis and temperature, and a negative correlation betweenrates of epistaxis and humidity, air pressure, and rainfall.13Other studies have not found a correlation between theambient temperature and epistaxis presentation rate.14Increased incidence of upper respiratory tract infections inwinter months has been suggested as the underlying reasonfor increased epistaxis admissions during the winter.7

In our study, the difference between the maximum andminimum daily temperatures was highest in summer(12.77°C) and lowest in winter (8.1°C). Adaptation ofnasal mucosa to fluctuations in daily temperature mightlead to nasal dryness and crusting in children and maypredispose to bleeding.Particulate matter (PM) is the term for a complexmixture of organic and inorganic solid particles andliquid droplets found in the air. Particles <10 μm canpenetrate farther into the lung and are considered moreirritant. SO2 is typically produced from the burning ofcoal and other sulfur-containing fossil fuels. Gasolineand diesel motor vehicles produce carbon monoxide(CO), nitrogen dioxide (NO2), and PM. Ozone (O3)is produced as a byproduct of these pollutants and isconsidered a long-range pollutant that is highly irritantto respiratory epithelium.17,22We found a negative correlation between rates ofepistaxis and PM10 and SO2 levels. One possibility forthe negative correlation may be that PM10 and SO2 levelsalone are not completely representative of air pollution.Another explanation may be that the duration and levelof exposure to these air pollutants in chil-dren is not high. Meteorologic conditionscan alter the intensity and the effects of airpollution. Bray et al and Zemek et al re-ported that the level of O3, which is anotherindicator of air pollution, is higher duringsummer, whereas the levels of most pol-lutants increase during cold weathers.17,22O3 levels are often higher in warmerweather because heat and sunlight increaseO3 formation. Children are at higher riskfrom O3 exposure because they spend moretime outdoors in warmer weather.23 O3 lev-els were not routinely measured in Konya,where our institution is located. However,a passive sampling method can infer the O3levels, which measured higher in summerthan in winter for a 15-day period.2 Szyszkowicz et al found that high PM10 and O3 levelsincreased the risk of epistaxis, and the associationbetween the epistaxis and the air pollution levels wasstronger in older individuals and in women.16 Brayet al also detected a relationship between PM10 andO3 levels and epistaxis, with no association foundbetween NO2, CO, and SO2 levels and the frequencyof epistaxis.17 Positive correlation between the airpollution and the epistaxis rates as shown in thosestudies may be the result of an indirect effect ofair pollution on blood pressure and coagulationparameters.16,25Our findings suggest that the frequency of epistaxisin children is greater in the summer and with low hu-midity. The incidence of posterior epistaxis or epistaxisassociated with systemic conditions might be differentor not show a seasonal variation pattern. High rates ofepistaxis in the winter, as reported in the literature,might be a result of coexisting risk factors other thanthe low temperature or air pollution alone. Culturaland traditional factors and factors not directly relatedto atmospheric conditions, such as digital trauma,Staphylococcus aureus colonization, or undeterminedcoexisting pathologies also may vary in differentpopulations and therefore may affect the frequency ofepistaxis in children.

Conclusion

Atmospheric conditions and air pollution affect thefrequency of epistaxis in children. Multicentric, popu-lation-based prospective studies covering different cli-matic conditions are needed to detect the exact effectof environmental factors on epistaxis rates.

References

1. Pertuson B. Epistaxis in childhood. Rhinology 1979;17(2):83-90.

2. Davies K, Batra K, Mehanna R, Keogh I. Pediatric epistaxis:epidemiology, management & impact on quality of life. Int JPediatr Otorhinolaryngol 2014;78(8):1294-7.

3. Qureishi A, Burton MJ. Interventions for recurrent idiopathicepistaxis (nosebleeds) in children. Cochrane Database Syst Rev2012;9:CD004461.

4. Purkey MR, Seeskin Z, Chandra R. Seasonal variation andpredictors of epistaxis. Laryngoscope 2014;124(9):2028-33.

5. Sowerby LJ, DeSerres JJ, Rudmik L, Wright ED. Role of season,temperature and humidity on the incidence of epistaxis inAlberta, Canada. J Otolaryngol Head Neck Surg 2014;43:10.

6. Muhammad R, Khan F, ul Abrar S, et al. Effect of temperatureand humidity on epistaxis in Hazara division. J Ayub Med CollAbbottabad 2013;25(3-4):61-3.

7. Reddy VM, Judd O, Khalil H. Investigation of the influence ofambient temperature, atmospheric pressure and water vapourpressure on epistaxis admission rate. Rhinology 2010;48(3):348-51.

8. Walker TW, Macfarlane TV, McGarry GW. The epidemiology andchronobiology of epistaxis: An investigation of Scottish hospitaladmissions 1995-2004. Clin Otolaryngol 2007;32(5):361-5.

9. Danielides V, Kontogiannis N, Bartzokas A, et al. The influenceofmeteorological factors on the frequency of epistaxis. ClinOtolaryngol Allied Sci 2002;27(2):84-8.

10. Tomkinson A, Bremmer-Smith A, Craven C, Roblin DG.Hospital epistaxis admission rate and ambient temperature. ClinOtolaryngol Allied Sci 1995;20(3):239-40.

11. Nunez DA, McClymont LG, Evans RA. Epistaxis: A study ofthe relationship with weather. Clin Otolaryngol Allied Sci1990;15(1):49-51.

12. Murata S, Maesaka A, Miyazaki T, et al. Statistical analysis ofepistaxis. Nihon Jibiinkoka Gakkai Kaiho 1978;81(7):655-64.

13. Kemal O, Sen E. Does the weather really affect epistaxis? B-ENT2014;10(3):199-202.

14. Bray D, Giddings CE, Monnery P, et al. Epistaxis: Are temperatureand seasonal variations true factors in incidence? J Laryngol Otol2005;119(9):724-6.

15. Kubba H. Childhood epistaxis. Clin Otolaryngol 2006;31(3):212-3.

16. Szyszkowicz M, Shutt R, Kousha T, Rowe BH. Air pollution andemergency department visits for epistaxis. Clin Otolaryngol2014;39(6):345-51.

17. Bray D, Monnery P, Toma AG. Airborne environmental pollutantconcentration and hospital epistaxis presentation: A 5-yearreview. Clin Otolaryngol Allied Sci 2004;29(6):655-8.

18. Manes RP. Evaluating and managing the patient with nosebleeds.Med Clin North Am 2010;94(5):903-12.

19. Brennan PJ, Greenberg G, Miall WE, Thompson SG. Seasonalvariation in arterial blood pressure. Br Med J (Clin Res Ed)1982;285(6346):919-23.

20. de Paula Santos U, Braga AL, Giorgi DM, et al. Effects of airpollution on blood pressure and heart rate variability: A panelstudy of vehicular traffic controllers in the city of São Paulo,Brazil. Eur Heart J 2005;26(2):193-200.

21. Gao J, Sun Y, Lu Y, Li L. Impact of ambient humidity on childhealth: A systematic review. PLoS One 2014;9(12):e112508.

22. Zemek R, Szyszkowicz M, Rowe BH. Air pollution and emergencydepartment visits for otitis media: A case-crossover study inEdmonton, Canada. Environ Health Perspect 2010;118(11):1631-6.

23. United States Environmental Protection Agency. Air Quality Index:A guide to air quality and your health. http://www.airnow.gov/index.cfm?action=aqi_brochure.index. Accessed July 7, 2018.

24. Republic of Turkey Ministry of Environment and UrbanPlanning. Konya Clean Air Action Plan (2013-2019).(KonyaTemiz Hava Eylem Plani 2013-2019). https://docplayer.biz.tr/9238070-Konya-temiz-hava-eylem-plani-2013-2019.html.Accessed July 7, 2018.

25. Seaton A, MacNee W, Donaldson K, Godden K. Particulate airpollution and acute health effects. Lancet 1995;345(8943):176-8.