Discussion
Our study findings reveal that a total of 39 confirmed or suspected cases of H1N1 presented to the hospital from January 2018 till December 2019. Clinical features included fever, shortness of breath, cough, chest pain, body aches and sore throat. The most commonly occurring comorbidities were hypertension, diabetes, and chronic kidney disease. Biochemical profile of these patients showed low levels of pO2 and pCO2 whereas CRP, ESR and Troponin I were raised above the normal reference values. Of the 39 participants, 30 (76.9%) survived while 09 (23.1%) did not survive. Comparison of the clinical parameters of survivors and non-survivors showed that non-survivors had significantly higher risk of renal failure, ionotropic disturbances, secondary infection, septic shock, and respiratory problems, requiring non-invasive ventilation and invasive mechanical ventilation.
In a study conducted by Ijaz M et. al, length of hospital stays had a significant impact on the survival of patients (p=0.006) with patients expiring significantly earlier than the survivors. (1)In our study, no such pattern was seen. This could be due to almost similar duration of stay in both survivors and death patients in our setup. The longer stay pertains to the patient developing hospital acquired infections and hence an increased chance of death. In another study by Kumar TCN, similar results to ours were found (p=0.254).(22)
In our study 36.67% survivors required ventilatory support while the remaining did not. All patients that died were on ventilatory support. A similar picture was seen in the study conducted in the same setup in 2017. (1) Patients requiring ventilatory support showed a significantly high mortality in other studies too (p<0.05). (23) Previously a similar study in China reported comparable results (16). Deaths were reported in 10 (14.7%) of the patients while the clinical manifestations were mainly cough in 60 (88%), respiratory problems in 31 (46%), and myalgia in 18 (27%) patients. Another study by Chudasama R, et al(17) was condcuted in 1726 patients in India. Simialr symptoms were reported amongst these patients [cough (93.9%), pyrexia (90.8%), shortness of breath (66.5%) and sore throat (59.9%)] while death was reported in 127 (24.9%) out of the total patients.
Fajardo-Dolci G, et al(18), in his study, described the comorbidities amongst patients with H1N1. Results from the study showed metabolic syndrome (40%), cardiovascular disease (21%), hypertension (20%) and diabetes mellitus (20%) as the main chronic medical conditions amongst these patients. These study findings are in line with our results where hypertension and diabetes were present in 53.8% and 28.2% of the patients respectively. Major clinical manifestations reported by Fajardo-Dolci G, et al(18)were pyrexia (84%), cough (85%), shortness of breath (75%) and muscle pain (30%). Similar findings have been documented by other research studies as well(19) (20).
A study was conducted in intensive care unit patients of H1N1 where the biochemical profile of all patients was similar to that of our study with significant differences seen in only the creatinine levels (1.9mg/dl compared to 1.14mg/dl). All other biochemical markers were in the same limits(21). CRP levels in our study were found to be higher compared to a study conducted by Ijaz M et.al while all the other biochemical parameters showed a similar trend(1).
In summary, our study has highlighted the important clinical features and its outcomes in H1N1 influenza patients in a hospital setting in Pakistan. Major clinical features were fever, shortness of breath, cough, chest pain, body aches and sore throat while most commonly occurring comorbidities were hypertension, diabetes, and chronic kidney disease. Biochemical profile of these patients showed low levels of pO2 and pCO2 whereas CRP, ESR and Troponin I were raised above the normal reference values. Non-survivors had significantly higher risk of renal failure, ionotropic disturbances, secondary infection, septic shock, and respiratory problems, requiring non-invasive ventilation and invasive mechanical ventilation.