Original Article Published on 14 Mar, 2024

Determinants of Hospital Length of Stay in Respiratory Infections: Insights from Cheras, Malaysia

Respiratory Infection and Admission Determinants
Vol. 19 No. 1 : 2024 (245-256)

Balakrishnan KG Balakrishnan KG
Abd Manaf MR Abd Manaf MR
Hassan MR Hassan MR
Musa KI Musa KI
Mohamad Jamil AR Mohamad Jamil AR
Satariah Ali UK Satariah Ali UK
Periyasamy P Periyasamy P
Jamal R Jamal R
Mohd Nadzir MS Mohd Nadzir MS

Abstract
Respiratory virus infections pose a significant public health concern, contributing to increase morbidity and mortality rates. This study investigated the determinants of hospital length of stay (LOS) for patients with Influenza-like illness (ILI) and Severe Acute Respiratory Infection (SARI). A quantitative study was conducted in Cheras, Kuala Lumpur, Malaysia, from 1 September 2022 until 28 February 2023. Demographic data, viral infection status (influenza A, influenza B, and COVID-19), and environmental factors (temperature, humidity, wind speed, and particulate matter levels) were collected for 632 patients. The data were analysed using ordinal logistic regression in Statistical Package for Social Sciences (SPSS) version 22.0. The results revealed that older age and higher body mass index (BMI) were associated with longer hospital stays, highlighting their significance as risk factors during respiratory outbreaks. Unexpectedly, patients tested positive for the investigated viruses experienced shorter LOS, indicating potential comorbidities or co-infections. Environmental factors played a critical role, with temperature, humidity, and wind speed significantly influencing LOS. These findings provided valuable insights for healthcare resource allocation during epidemics and underscored the need for comprehensive diagnostic tools and further research to enhance prediction accuracy.
Keywords : Health management, public health, respiratory infection,
Abstrak
Jangkitan virus pernafasan menimbulkan kebimbangan kesihatan awam yang ketara, menyumbang kepada peningkatan kadar morbiditi dan kematian. Kajian ini mengkaji faktor-faktor yang mempengaruhi tempoh tinggal di hospital (LOS) bagi pesakit yang didiagnosis dengan "Influenza-like illness" (ILI) dan "Severe Acute Respiratory Infection" (SARI). Kajian kuantitatif telah dijalankan di Cheras, Kuala Lumpur, Malaysia, dari 1 September 2022 hingga 28 Februari 2023. Data tentang demografi, status jangkitan virus (khususnya influenza A, influenza B, dan COVID-19), serta parameter persekitaran seperti suhu, kelembapan, kelajuan angin, dan paras zarah, telah dikumpulkan untuk 632 individu. Data dianalisis menggunakan regresi logistik ordinal dalam Statistical Package for Social Sciences (SPSS) versi 22.0. Penemuan menunjukkan korelasi antara usia lanjut dan indeks jisim badan (BMI) yang tinggi dengan tempoh kemasukan ke hospital yang panjang, menekankan kepentingannya sebagai faktor risiko dalam konteks wabak pernafasan. Tanpa diduga, pesakit yang diuji positif untuk virus yang disiasat mempunyai LOS yang lebih pendek, menunjukkan kehadiran keadaan perubatan lain atau jangkitan serentak. Parameter persekitaran, seperti suhu, kelembapan dan kelajuan angin, mempunyai kesan yang besar pada LOS. Penemuan ini menawarkan pandangan yang berguna untuk memperuntukkan sumber penjagaan kesihatan semasa wabak dan menekankan kepentingan teknik diagnostik yang komprehensif dan penyelidikan tambahan untuk meningkatkan ketepatan ramalan.
Kata Kunci : Jangkitan pernafasan, kesihatan awam, pengurusan kesihatan,

Correspondance Address
Mohd Rohaizat Hassan / Kamarul Imran Musa. Department of Public Health Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia (UKM), Jalan Ya’acob Latiff, Bandar Tun Razak, Cheras, Kuala Lumpur, Malaysia / Department of Community Medicine, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia. Tel: +6012-6343303 / +6013-9302002 Email: rohaizat@ppukm.ukm.edu.my / drkamarul@usm.my

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Shaman, J., Kohn, M. 2009. Absolute humidity modulates influenza survival, transmission, and seasonality. Proc Natl Acad Sci 106(9): 3243-8.

Simonsen, L., Spreeuwenberg, P., Lustig, R., Taylor, R.J., Fleming, D.M., Kroneman, M., Van Kerkhove, M.D., Mounts, A.W., Paget, W.J. 2013. Global mortality estimates for the 2009 influenza pandemic from the GLaMOR Project: A modeling study. PLoS Med 10(11): e1001558.

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Zhao, X., Gang, X., He, G., Li, Z., Lv, Y., Han, Q., Wang, G. 2020. Obesity increases the severity and mortality of influenza and COVID-19: A systematic review and meta-analysis. Front Endocrinol 11(December).

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Correspondance Address

Centre for Disease Control and Prevention (CDC). 2022. Influenza (flu). https://www.cdc.gov/flu/about/disease/spread.htm [15 August 2022].

Chen, W., Zhang, X., Zhao, W., Yang, L., Wang, Z., Bi, H. 2022. Environmental factors and spatiotemporal distribution characteristics of the global outbreaks of the highly pathogenic avian influenza H5N1. Environ Sci Pollut Res 29(29): 44175-85.

Darwish, A., Rahhal, Y., Jafar, A. 2020. A comparative study on predicting influenza outbreaks using different feature spaces: Application of influenza-like illness data from early warning alert and response system in Syria. BMC Res Notes 13(1): 33.

Giurgea, L.T., Cervantes-Medina, A., Walters, K.A., Scherler, K., Han, A., Czajkowski, L.M., Baus, H.A., Hunsberger, S., Klein, S.L., Kash, J.C., Taubenberger, J.K., Memoli, M.J. 2022. Sex differences in Influenza: The challenge study experience. J Infect Dis 225(4): 715-22.

Grunberg, M., Sno, R., Adhin, M.R. 2021. Epidemiology of respiratory viruses in patients with severe acute respiratory infections and influenza-like illness in Suriname. Influenza Other Resp Viruses 15(1): 72-80.

Hashim, J.H., Adman, M.A., Hashim, Z., Mohd Radi, M.F., Kwan, S.C. 2021. COVID-19 Epidemic in Malaysia: Epidemic progression, challenges, and response. Front Public Heal 9(May): 1-19.

Hernandez-Vargas, E.A., Wilk, E., Canini, L., Toapanta, F.R., Binder, S.C., Uvarovskii, A., Ross, T.M., Guzmán, C.A., Perelson, A.S., Meyer-Hermann, M. 2014. Effects of aging on influenza virus infection dynamics. J Virol 88(8): 4123-31.

Iuliano, A.D., Roguski, K.M., Chang, H.H., Muscatello, D.J., Palekar, R., Tempia, S., Cohen, C., Gran, J. M., Schanzer, D., Cowling, B.J., et al. 2018. Estimates of global seasonal influenza-associated respiratory mortality: A modelling study. Lancet 391(10127): 1285-300.

Long, J.S., Freese, J. 2014. Regression models for categorical deependent variables using stata. Third Edition. College Station: Stata Press.

Maccioni, L., Weber, S., Elgizouli, M., Stoehlker, A.S., Geist, I., Peter, H.H., Vach, W., Nieters, A. 2018. Obesity and risk of respiratory tract infections: Results of an infection-diary based cohort study. BMC Public Health 18(1): 271.

Neidich, S.D., Green, W.D., Rebeles, J., Karlsson, E.A., Schultz-Cherry, S., Noah, T.L., Chakladar, S., Hudgens, M.G., Weir, S.S., Beck, M.A. 2017. Increased risk of influenza among vaccinated adults who are obese. Int J Obes 41(9): 1324-30.

Oong, X.Y., Ng, K.T., Lam, T.T.Y., Pang, Y.K., Chan, K.G., Hanafi, N.S., Kamarulzaman, A., Tee, K.K. 2015. Epidemiological and evolutionary dynamics of influenza B viruses in Malaysia, 2012-2014. PLoS One 10(8): e0136254.

Paynter, S. 2015. Humidity and respiratory virus transmission in tropical and temperate settings. Epidemiol. Infect. 143(6): 1110-8.

Pica, N., Bouvier, N.M. 2012. Environmental factors affecting the transmission of respiratory viruses. Curr Opin Virol 2(1): 90-5.

Rahman, M.M. 1969. Identification of genotypes of influenza A virus in Malaysia. Pakistan J Med Sci 30(5): 1068-71.

Rahman, M.M. 2013. Influenza and respiratory syncytial viral infections in Malaysia: Demographic and clinical perspective. Pak J Med Sci 30(1): 161-5.

Reswell, J.W., Creswell, J.D. 2017. Research design: Qualitative, quantitative, and mixed methods approaches. Thousand Oaks: Sage Publications.

Saha, S., Chadha, M., Shu, Y. 2016. Divergent seasonal patterns of influenza types A and B across latitude gradient in Tropical Asia. Influenza Other Respi Viruses 10(3): 176-84.

Sam, I.C., Su, Y.C.F., Chan, Y.F., Nor’E, S.S., Hassan, A., Jafar, F.L., Joseph, U., Halpin, R.A., Ghedin, E., Hooi, P.S., Fourment, M., Hassan, H., AbuBakar, S., Wentworth, D.E., Smith, G.J.D. 2015. Evolution of Influenza B Virus in Kuala Lumpur, Malaysia, between 1995 and 2008. J Virol 89(18): 9689-92.

Sam, I.C.J. 2015. The burden of human influenza in Malaysia. Med J Malaysia 70(3): 127-30.

Shaman, J., Kohn, M. 2009. Absolute humidity modulates influenza survival, transmission, and seasonality. Proc Natl Acad Sci 106(9): 3243-8.

Simonsen, L., Spreeuwenberg, P., Lustig, R., Taylor, R.J., Fleming, D.M., Kroneman, M., Van Kerkhove, M.D., Mounts, A.W., Paget, W.J. 2013. Global mortality estimates for the 2009 influenza pandemic from the GLaMOR Project: A modeling study. PLoS Med 10(11): e1001558.

Stone, K., Zwiggelaar, R., Jones, P., Mac Parthaláin, N. 2022. A systematic review of the prediction of hospital length of stay: Towards a unified framework. PLOS Digit Health 1(4): e0000017.

Tang, J.W., Lam, T.T., Zaraket, H., Lipkin, W.I., Drews, S.J., Hatchette, T.F., Heraud, J.M., Koopmans, M.P., INSPIRE investigators. 2017. Global epidemiology of non-influenza RNA respiratory viruses: Data gaps and a growing need for surveillance. Lancet Infect Dis 17(10): e320-6.

Turner, D., Wailoo, A., Nicholson, K., Cooper, N., Sutton, A., Abrams, K. 2003. Systematic review and economic decision modelling for the prevention and treatment of influenza A and B. Health Technol Assess 7(35): iii-iv, xi-xiii, 1-170.

Venkatramanan, S., Sadilek, A., Fadikar, A., Barrett, C.L., Biggerstaff, M., Chen, J., Dotiwalla, X., Eastham, P., Gipson, B., Higdon, D., Kucuktunc, O., Lieber, A., Lewis, B.L., Reynolds, Z., Vullikanti, A.K., Wang, L., Marathe, M. 2021. Forecasting influenza activity using machine-learned mobility map. Nat Commun 12(1): 726.

World Heahlt Organization. 2020. World Life Expectancy. https://www.worldlifeexpectancy.com/country-health-profile/malaysia [1 August 2022].

Zhao, X., Gang, X., He, G., Li, Z., Lv, Y., Han, Q., Wang, G. 2020. Obesity increases the severity and mortality of influenza and COVID-19: A systematic review and meta-analysis. Front Endocrinol 11(December).

Zhao, Y., Richardson, B., Takle, E., Chai, L., Schmitt, D., Xin, H. 2019. Airborne transmission may have played a role in the spread of 2015 highly pathogenic avian influenza outbreaks in the United States. Sci Rep 9(1): 11755.



Centre for Disease Control and Prevention (CDC). 2022. Influenza (flu). https://www.cdc.gov/flu/about/disease/spread.htm [15 August 2022].

Chen, W., Zhang, X., Zhao, W., Yang, L., Wang, Z., Bi, H. 2022. Environmental factors and spatiotemporal distribution characteristics of the global outbreaks of the highly pathogenic avian influenza H5N1. Environ Sci Pollut Res 29(29): 44175-85.

Darwish, A., Rahhal, Y., Jafar, A. 2020. A comparative study on predicting influenza outbreaks using different feature spaces: Application of influenza-like illness data from early warning alert and response system in Syria. BMC Res Notes 13(1): 33.

Giurgea, L.T., Cervantes-Medina, A., Walters, K.A., Scherler, K., Han, A., Czajkowski, L.M., Baus, H.A., Hunsberger, S., Klein, S.L., Kash, J.C., Taubenberger, J.K., Memoli, M.J. 2022. Sex differences in Influenza: The challenge study experience. J Infect Dis 225(4): 715-22.

Grunberg, M., Sno, R., Adhin, M.R. 2021. Epidemiology of respiratory viruses in patients with severe acute respiratory infections and influenza-like illness in Suriname. Influenza Other Resp Viruses 15(1): 72-80.

Hashim, J.H., Adman, M.A., Hashim, Z., Mohd Radi, M.F., Kwan, S.C. 2021. COVID-19 Epidemic in Malaysia: Epidemic progression, challenges, and response. Front Public Heal 9(May): 1-19.

Hernandez-Vargas, E.A., Wilk, E., Canini, L., Toapanta, F.R., Binder, S.C., Uvarovskii, A., Ross, T.M., Guzmán, C.A., Perelson, A.S., Meyer-Hermann, M. 2014. Effects of aging on influenza virus infection dynamics. J Virol 88(8): 4123-31.

Iuliano, A.D., Roguski, K.M., Chang, H.H., Muscatello, D.J., Palekar, R., Tempia, S., Cohen, C., Gran, J. M., Schanzer, D., Cowling, B.J., et al. 2018. Estimates of global seasonal influenza-associated respiratory mortality: A modelling study. Lancet 391(10127): 1285-300.

Long, J.S., Freese, J. 2014. Regression models for categorical deependent variables using stata. Third Edition. College Station: Stata Press.

Maccioni, L., Weber, S., Elgizouli, M., Stoehlker, A.S., Geist, I., Peter, H.H., Vach, W., Nieters, A. 2018. Obesity and risk of respiratory tract infections: Results of an infection-diary based cohort study. BMC Public Health 18(1): 271.

Neidich, S.D., Green, W.D., Rebeles, J., Karlsson, E.A., Schultz-Cherry, S., Noah, T.L., Chakladar, S., Hudgens, M.G., Weir, S.S., Beck, M.A. 2017. Increased risk of influenza among vaccinated adults who are obese. Int J Obes 41(9): 1324-30.

Oong, X.Y., Ng, K.T., Lam, T.T.Y., Pang, Y.K., Chan, K.G., Hanafi, N.S., Kamarulzaman, A., Tee, K.K. 2015. Epidemiological and evolutionary dynamics of influenza B viruses in Malaysia, 2012-2014. PLoS One 10(8): e0136254.

Paynter, S. 2015. Humidity and respiratory virus transmission in tropical and temperate settings. Epidemiol. Infect. 143(6): 1110-8.

Pica, N., Bouvier, N.M. 2012. Environmental factors affecting the transmission of respiratory viruses. Curr Opin Virol 2(1): 90-5.

Rahman, M.M. 1969. Identification of genotypes of influenza A virus in Malaysia. Pakistan J Med Sci 30(5): 1068-71.

Rahman, M.M. 2013. Influenza and respiratory syncytial viral infections in Malaysia: Demographic and clinical perspective. Pak J Med Sci 30(1): 161-5.

Reswell, J.W., Creswell, J.D. 2017. Research design: Qualitative, quantitative, and mixed methods approaches. Thousand Oaks: Sage Publications.

Saha, S., Chadha, M., Shu, Y. 2016. Divergent seasonal patterns of influenza types A and B across latitude gradient in Tropical Asia. Influenza Other Respi Viruses 10(3): 176-84.

Sam, I.C., Su, Y.C.F., Chan, Y.F., Nor’E, S.S., Hassan, A., Jafar, F.L., Joseph, U., Halpin, R.A., Ghedin, E., Hooi, P.S., Fourment, M., Hassan, H., AbuBakar, S., Wentworth, D.E., Smith, G.J.D. 2015. Evolution of Influenza B Virus in Kuala Lumpur, Malaysia, between 1995 and 2008. J Virol 89(18): 9689-92.

Sam, I.C.J. 2015. The burden of human influenza in Malaysia. Med J Malaysia 70(3): 127-30.

Shaman, J., Kohn, M. 2009. Absolute humidity modulates influenza survival, transmission, and seasonality. Proc Natl Acad Sci 106(9): 3243-8.

Simonsen, L., Spreeuwenberg, P., Lustig, R., Taylor, R.J., Fleming, D.M., Kroneman, M., Van Kerkhove, M.D., Mounts, A.W., Paget, W.J. 2013. Global mortality estimates for the 2009 influenza pandemic from the GLaMOR Project: A modeling study. PLoS Med 10(11): e1001558.

Stone, K., Zwiggelaar, R., Jones, P., Mac Parthaláin, N. 2022. A systematic review of the prediction of hospital length of stay: Towards a unified framework. PLOS Digit Health 1(4): e0000017.

Tang, J.W., Lam, T.T., Zaraket, H., Lipkin, W.I., Drews, S.J., Hatchette, T.F., Heraud, J.M., Koopmans, M.P., INSPIRE investigators. 2017. Global epidemiology of non-influenza RNA respiratory viruses: Data gaps and a growing need for surveillance. Lancet Infect Dis 17(10): e320-6.

Turner, D., Wailoo, A., Nicholson, K., Cooper, N., Sutton, A., Abrams, K. 2003. Systematic review and economic decision modelling for the prevention and treatment of influenza A and B. Health Technol Assess 7(35): iii-iv, xi-xiii, 1-170.

Venkatramanan, S., Sadilek, A., Fadikar, A., Barrett, C.L., Biggerstaff, M., Chen, J., Dotiwalla, X., Eastham, P., Gipson, B., Higdon, D., Kucuktunc, O., Lieber, A., Lewis, B.L., Reynolds, Z., Vullikanti, A.K., Wang, L., Marathe, M. 2021. Forecasting influenza activity using machine-learned mobility map. Nat Commun 12(1): 726.

World Heahlt Organization. 2020. World Life Expectancy. https://www.worldlifeexpectancy.com/country-health-profile/malaysia [1 August 2022].

Zhao, X., Gang, X., He, G., Li, Z., Lv, Y., Han, Q., Wang, G. 2020. Obesity increases the severity and mortality of influenza and COVID-19: A systematic review and meta-analysis. Front Endocrinol 11(December).

Zhao, Y., Richardson, B., Takle, E., Chai, L., Schmitt, D., Xin, H. 2019. Airborne transmission may have played a role in the spread of 2015 highly pathogenic avian influenza outbreaks in the United States. Sci Rep 9(1): 11755.