Agreement among sources of adult influenza vaccination in the age of immunization information systems.

INTRODUCTION: Many vaccination studies rely on self-reported vaccination status, with its inherent biases. Accuracy of influenza vaccination self-report has been evaluated periodically, typically using the medical record as the gold standard. The burgeoning of electronic medical records (EMRs) and immunization information systems (IISs) and the rise of adult vaccine administration in community pharmacies suggest the need for a reevaluation of self-reported vaccination status. METHODS: Vaccination data from self-report, the state IIS, the health system EMR and other sources were compared for participants in outpatient and inpatient influenza vaccine effectiveness studies for four seasons (2016-2017 to 2019-2020). Agreement among the sources was calculated along with sensitivity and specificity. Tests for trend assessed changes in completeness of the Pennsylvania - Statewide IIS (PA-SIIS) data over time. RESULTS: With self-report as the gold standard, agreement with the local EMR, PA-SIIS, and all sources was 62%, 77% and 85%, respectively. Sensitivity of the EMR was 42% (95% CI = 41, 43) and specificity was 91% (90, 92). With PA-SIIS-as the gold standard, agreement with the local EMR and all sources was 77% and 78%, respectively. Sensitivity of all sources combined was 96% (95, 97) and specificity was (63% (62, 64). Capture of influenza vaccinations in the IIS has not consistently improved over time, with a significant increase among children (P = 0.001), no change among working-age adults and a decrease among older adults (P = 0.004). However, PA-SIIS provided the largest percentage of verified vaccines (69.3%) compared with EMR (43.3%) and other sources (12.4%). CONCLUSION: Both self-report and PA-SIIS are good estimates of actual vaccine uptake. When high accuracy data are required, such as for vaccine effectiveness studies, triangulation using multiple sources should be conducted.

Physical health and mental health functional status during and following hospitalization for an acute respiratory illness.

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 ±â€¯8.1; P = 0.017) and mental health (-5.98 ±â€¯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.

Determination of Eligibility for Influenza Research: A Clinical Informatics Approach.

BACKGROUND: A clinical informatics algorithm (CIA) was developed to systematically identify potential enrollees for a test-negative, case-control study to determine influenza vaccine effectiveness, to improve enrollment over manual records review. Further testing may enhance the CIA for increased efficiency. METHODS: The CIA generated a daily screening list by querying all medical record databases for patients admitted in the last 3 days, using specified terms and diagnosis codes located in admission notes, emergency department notes, chief complaint upon registration, or presence of a respiratory viral panel charge or laboratory result (RVP). Classification and regression tree analysis (CART) and multivariable logistic regression were used to refine the algorithm. RESULTS: Using manual records review, 204 patients (<4/day) were approached and 144 were eligible in the 2014-2015 season compared with 3531 (12/day) patients who were approached and 1136 who were eligible in the 2016-2017 season using a CIA. CART analysis identified RVP as the most important indicator from the CIA list for determining eligibility, identifying 65%-69% of the samples and predicting 1587 eligible patients. RVP was confirmed as the most significant predictor in regression analysis, with an odds ratio (OR) of 4.9 (95% confidence interval [CI], 4.0-6.0). Other significant factors were indicators in admission notes (OR, 2.3 [95% CI, 1.9-2.8]) and emergency department notes (OR, 1.8 [95% CI, 1.4-2.3]). CONCLUSIONS: This study supports the benefits of a CIA to facilitate recruitment of eligible participants in clinical research over manual records review. Logistic regression and CART identified potential eligibility screening criteria reductions to improve the CIA's efficiency.

Does influenza vaccination status change physician ordering patterns for respiratory viral panels? Inspection for selection bias.

PURPOSE: Hospitalized patients with an acute respiratory illness (ARI) were compared to determine if demographic characteristics, timing or influenza vaccination biased who received clinical respiratory viral panel (RVP) testing. METHODS: 171 enrollees in an influenza vaccine effectiveness study and a sample of non-enrollees (N = 1029) admitted to a community hospital with ARI during December 2015 through April 2016 comprised the study sample. Those who received clinical RVP testing (n = 292) were compared to those who did not by age, sex, influenza vaccination status, and period (pre-peak influenza season vs. peak/post peak influenza season), using Chi square- and t-tests, and logistic regression. RESULTS: Mean age of participants was 70 years, 58% was female and 45% had been vaccinated against influenza in the 2015-2016 season. Those with clinical RVP testing were significantly younger (67 years) than those without RVP (71 years; P < 0.001), but did not differ with respect to sex or vaccination status. The odds of clinical RVP testing were significantly (P = 0.004) related to younger age (< 65 years) (Odds ratio (OR) = 1.51; 95% CI = 1.14-2.00) and to later period (peak/post peak influenza season; OR = 2.64; 95% CI = 1.84-3.79) but were unrelated to influenza vaccination status or the interaction of time and vaccination status. CONCLUSION: RVP testing was significantly higher among younger hospitalized patients with an ARI and during the peak and post peak influenza periods than earlier in the season, but influenza vaccination status was not a significant factor. Studies that enroll based on clinical RVP testing should account for potential differences by age.

The effect of frailty on HAI response to influenza vaccine among community-dwelling adults ≥ 50 years of age.

The immune response to vaccine antigens is less robust in older adults because of changes in the aging immune system. Frailty, the multi-dimensional syndrome marked by losses in function and physiological reserve, is increasingly prevalent with advancing age. Frailty accelerates this immunosenescence but the consequence of frailty on immune response specific to influenza vaccine among older adults, is mixed. An observational, prospective study of 114 adults was conducted in the fall of 2013 to assess the association of physical frailty with immune response to standard dose influenza vaccine in community-dwelling adults ≥ 50 years of age. Participants were stratified by age (<65 years and ≥65 years), and vaccine strain (Influenza A/H1N1, A/H3N2 and B) was analyzed separately adjusting for body mass index (BMI) and baseline log2 hemagglutination inhibition (HAI) titers. Overall, immune responses were lower among those ≥65 years of age than those <65 years. Among those ≥65 years there were no significant differences between frail and non-frail individuals in seroprotection or seroconversion for any influenza strain. Frail individuals <65 years of age compared with non-frail individuals were more likely to be seroprotected and to seroconvert post vaccination. Linear regression models show the same pattern of significant differences between frail and non-frail for those <65 years but no significant differences between frailty groups for those ≥65 years. Additional research may elucidate the reasons for the differences observed between younger frail and non-frail adults.

Are plasma mineral levels related to antibody response to influenza vaccination in older adults?

INTRODUCTION: An effective immune response to vaccination may be related to nutritional status. This study examined the association of plasma mineral levels with hemagglutination inhibition (HI) titers produced in response to influenza vaccine in older adults. METHODS: Prior to (Day 0) and 21 (range = 19-28) days after receiving the 2013-14 influenza vaccine, 109 adults ages 51-81 years, provided blood samples. Serum samples were tested for HI activity against the A/H1N1 and A/H3N2 2013-2014 vaccine virus strains. Plasma minerals were collected in zinc-free tubes and assayed by inductively coupled plasma mass spectrometry. HI titers were reported as seroprotection (≥1:40) and seroconversion (≥ 4-fold rise from Day 0 (minimum HI = 1:10) to Day 21). Both HI titers and mineral values were skewed and thus log2 transformed. Magnesium (Mg), phosphorus (P), zinc (Zn), copper (Cu), iron (Fe), potassium (K) and the Cu to Zn ratio were tested. Logistic regression analyses were used to determine the associations between mineral levels and seroconversion and seroprotection of HI titers for each influenza A strain. RESULTS: Participants were 61% white, 28% male, 39% diabetic, and 81% overweight/obese with a mean age of 62.6 y. In logistic regression, Day 21 A/H1N1 seroprotection was associated with P and Zn at Day 21(P < 0.05). Seroconversion of A/H1N1 was associated with Day 21 Cu, P, and Mg (P < 0.03). Day 21 A/H3N2 seroprotection and seroconversion were associated with Day 21 P (P < 0.05). CONCLUSIONS: Phosphorus was associated with seroprotection and seroconversion to influenza A after vaccination; these associations warrant additional studies with larger, more diverse population groups.