Abstract
BACKGROUND: Influenza is a serious respiratory illness causing thousands of hospitalizations annually. This study used the Short Form 12 (SF-12) to evaluate physical and mental health status during and post hospitalization for an acute respiratory illness (ARI). METHODS: Adults ≥18 years of age enrolled in the Hospitalized Adult Influenza Vaccine Effectiveness Network study - Pittsburgh site in the 2017-2018 and 2018-2019 influenza seasons with an ARI with cough of ≤10 days' duration were eligible. Enrollees were included regardless of respiratory pathogen identified by respiratory viral panel testing of nasopharyngeal specimens. Respondents completed the SF-12 at enrollment and 3-14 weeks later. Respondents were grouped using discriminant cluster analysis based on SF-12 individual scores and age. Linear regression was used to predict convalescent physical and mental health composite scores. RESULTS: Of 72 enrollees who completed both surveys, 35 were grouped as the high functioning group (HFG), 12 as the low functioning group (LFG) and 25 as the medium functioning group (MFG). At enrollment, the LFG more frequently reported body aches and confusion, lower pre-illness physical activity levels and other measures of physical function than the HFG (P < 0.016). At approximately 5 weeks post enrollment, the HFG reported significant decrements in most SF-12 individual scores and overall physical health (-4.26 ± 8.1; P = 0.017) and mental health (-5.98 ± 10.5; P = 0.011) composite scores. Changes in mental but not physical composite scores from enrollment to convalescence differed significantly (P = 0.016) between HFG and LFG. CONCLUSIONS: Although their enrollment and convalescent SF-12 scores were higher, HFG reported larger losses in mental function during an ARI hospitalization than groups with lower enrollment SF-12 scores.