Abstract
Background
In the United States, it is recommended that healthcare providers offer influenza vaccination by October, if possible. However, if the vaccine’s effectiveness soon begins to wane, ...the optimal time for vaccination may be somewhat later. We examined whether the effectiveness of influenza vaccine wanes during the influenza season with increasing time since vaccination.
Methods
We identified persons who were vaccinated with inactivated influenza vaccine from 1 September 2010 to 31 March 2017 and who were subsequently tested for influenza and respiratory syncytial virus (RSV) by a polymerase chain reaction test. Test-confirmed influenza was the primary outcome and days-since-vaccination was the predictor of interest in conditional logistic regression. Models were adjusted for age and conditioned on calendar day and geographic area. RSV was used as a negative-control outcome.
Results
Compared with persons vaccinated 14 to 41 days prior to being tested, persons vaccinated 42 to 69 days prior to being tested had 1.32 (95% confidence interval CI, 1.11 to 1.55) times the odds of testing positive for any influenza. The odds ratio (OR) increased linearly by approximately 16% for each additional 28 days since vaccination. The OR was 2.06 (95% CI, 1.69 to 2.51) for persons vaccinated 154 or more days prior to being tested. No evidence of waning was found for RSV.
Conclusions
Our results suggest that effectiveness of inactivated influenza vaccine wanes during the course of a single season. These results may lead to reconsideration of the optimal timing of seasonal influenza vaccination.
Vaccine effectiveness appears to decrease with time since vaccination. The odds of influenza in remote vaccinees vs recent vaccinees increased by about 16% per 28 days. Influenza vaccination may be more effective if received closer to the start of the influenza season.
To determine whether participation in early cardiac rehabilitation (CR) after heart transplant (HTx) affects long-term survival.
A retrospective review was conducted in 201 patients who underwent HTx ...at Mayo Clinic between June 1, 2000, and July 31, 2013. Patients were excluded with multiorgan transplant, no CR data, and follow-up less than 90 days after HTx. Demographic and exercise data at baseline before HTx were collected. Post-HTx exercise capacity, biopsy, CR data, and medications were collected at 1 through 5 and 10 years.
Overall survival at 1, 5, and 10 years was 98%, 88%, and 82%, respectively; 29 patients died. Number of CR sessions attended in the first 90 days after HTx predicted survival in multivariate regression, controlling for baseline post-HTx 6-minute walk test (6MWT) results and rejection episodes (hazard ratio, 0.90; 95% CI, 0.82-0.97; P=.007). Additional univariate predictors of survival included pre-HTx 6MWT results, weight at HTx, and body mass index and systolic blood pressure at CR enrollment. Pre-HTx 6MWT results, body mass index, and post-HTx were associated with improvement in peak oxygen consumption.
This report demonstrates, for the first time, an association between CR and long-term survival in patients after HTx. Further work should clarify the most beneficial aspects of CR.
We examined the effectiveness of maternal vaccination against SARS-CoV-2 infection in 30,311 infants born at Kaiser Permanente Northern California from December 15, 2020, to May 31, 2022. Using Cox ...regression, the effectiveness of ≥2 doses of COVID-19 vaccine received during pregnancy was 84% (95% confidence interval CI: 66, 93), 62% (CI: 39, 77) and 56% (CI: 34,71) during months 0-2, 0-4 and 0- 6 of a child's life, respectively, in the Delta variant period. In the Omicron variant period, the effectiveness of maternal vaccination in these three age intervals was 21% (CI: -21,48), 14% (CI: -9,32) and 13% (CI: -3,26), respectively. Over the entire study period, the incidence of hospitalization for COVID-19 was lower during the first 6 months of life among infants of vaccinated mothers compared with infants of unvaccinated mothers (21/100,000 person-years vs. 100/100,000 person-years). Maternal vaccination was protective, but protection was lower during Omicron than during Delta. Protection during both periods decreased as infants aged.
Racial disparities exist in outcomes after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.
To evaluate the contribution of race/ethnicity in SARS-CoV-2 testing, infection, and ...outcomes.
Retrospective cohort study (1 February 2020 to 31 May 2020).
Integrated health care delivery system in Northern California.
Adult health plan members.
Age, sex, neighborhood deprivation index, comorbid conditions, acute physiology indices, and race/ethnicity; SARS-CoV-2 testing and incidence of positive test results; and hospitalization, illness severity, and mortality.
Among 3 481 716 eligible members, 42.0% were White, 6.4% African American, 19.9% Hispanic, and 18.6% Asian; 13.0% were of other or unknown race. Of eligible members, 91 212 (2.6%) were tested for SARS-CoV-2 infection and 3686 had positive results (overall incidence, 105.9 per 100 000 persons; by racial group, White, 55.1; African American, 123.1; Hispanic, 219.6; Asian, 111.7; other/unknown, 79.3). African American persons had the highest unadjusted testing and mortality rates, White persons had the lowest testing rates, and those with other or unknown race had the lowest mortality rates. Compared with White persons, adjusted testing rates among non-White persons were marginally higher, but infection rates were significantly higher; adjusted odds ratios aORs for African American persons, Hispanic persons, Asian persons, and persons of other/unknown race were 2.01 (95% CI, 1.75 to 2.31), 3.93 (CI, 3.59 to 4.30), 2.19 (CI, 1.98 to 2.42), and 1.57 (CI, 1.38 to 1.78), respectively. Geographic analyses showed that infections clustered in areas with higher proportions of non-White persons. Compared with White persons, adjusted hospitalization rates for African American persons, Hispanic persons, Asian persons, and persons of other/unknown race were 1.47 (CI, 1.03 to 2.09), 1.42 (CI, 1.11 to 1.82), 1.47 (CI, 1.13 to 1.92), and 1.03 (CI, 0.72 to 1.46), respectively. Adjusted analyses showed no racial differences in inpatient mortality or total mortality during the study period. For testing, comorbid conditions made the greatest relative contribution to model explanatory power (77.9%); race only accounted for 8.1%. Likelihood of infection was largely due to race (80.3%). For other outcomes, age was most important; race only contributed 4.5% for hospitalization, 12.8% for admission illness severity, 2.3% for in-hospital death, and 0.4% for any death.
The study involved an insured population in a highly integrated health system.
Race was the most important predictor of SARS-CoV-2 infection. After infection, race was associated with increased hospitalization risk but not mortality.
The Permanente Medical Group, Inc.
Parental refusal and delay of childhood vaccines has increased in recent years and is believed to cluster in some communities. Such clusters could pose public health risks and barriers to achieving ...immunization quality benchmarks. Our aims were to (1) describe geographic clusters of underimmunization and vaccine refusal, (2) compare clusters of underimmunization with different vaccines, and (3) evaluate whether vaccine refusal clusters may pose barriers to achieving high immunization rates.
We analyzed electronic health records among children born between 2000 and 2011 with membership in Kaiser Permanente Northern California. The study population included 154,424 children in 13 counties with continuous membership from birth to 36 months of age. We used spatial scan statistics to identify clusters of underimmunization (having missed 1 or more vaccines by 36 months of age) and vaccine refusal (based on International Classification of Diseases, Ninth Revision, Clinical Modification codes).
We identified 5 statistically significant clusters of underimmunization among children who turned 36 months old during 2010-2012. The underimmunization rate within clusters ranged from 18% to 23%, and the rate outside them was 11%. Children in the most statistically significant cluster had 1.58 (P < .001) times the rate of underimmunization as others. Underimmunization with measles, mumps, rubella vaccine and varicella vaccines clustered in similar geographic areas. Vaccine refusal also clustered, with rates of 5.5% to 13.5% within clusters, compared with 2.6% outside them.
Underimmunization and vaccine refusal cluster geographically. Spatial scan statistics may be a useful tool to identify locations with challenges to achieving high immunization rates, which deserve focused intervention.
Substantial data have established a sedentary lifestyle as a major modifiable risk factor for coronary heart disease (CHD). Increased levels of physical activity, exercise training, and overall ...cardiorespiratory fitness have provided protection in the primary and secondary prevention of CHD. This review surveys data from observational studies supporting the benefits of physical activity, exercise training, and overall cardiorespiratory fitness in primary prevention. Clearly, cardiac rehabilitation/secondary prevention (CRSP) programs have been greatly underused by patients with CHD. We review the benefits of CRSP programs on CHD risk factors, psychological factors, and overall CHD morbidity and mortality. These data support the routine referral of patients with CHD to CRSP programs. Patients should be vigorously encouraged to attend these programs.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) antibody measurements can be used to estimate the proportion of a population exposed or infected and may be ...informative about the risk of future infection. Previous estimates of the duration of antibody responses vary.
We present 6 months of data from a longitudinal seroprevalence study of 3276 UK healthcare workers (HCWs). Serial measurements of SARS-CoV-2 anti-nucleocapsid and anti-spike IgG were obtained. Interval censored survival analysis was used to investigate the duration of detectable responses. Additionally, Bayesian mixed linear models were used to investigate anti-nucleocapsid waning.
Anti-spike IgG levels remained stably detected after a positive result, for example, in 94% (95% credibility interval CrI 91-96%) of HCWs at 180 days. Anti-nucleocapsid IgG levels rose to a peak at 24 (95% CrI 19-31) days post first polymerase chain reaction (PCR)-positive test, before beginning to fall. Considering 452 anti-nucleocapsid seropositive HCWs over a median of 121 days from their maximum positive IgG titer, the mean estimated antibody half-life was 85 (95% CrI 81-90) days. Higher maximum observed anti-nucleocapsid titers were associated with longer estimated antibody half-lives. Increasing age, Asian ethnicity, and prior self-reported symptoms were independently associated with higher maximum anti-nucleocapsid levels and increasing age and a positive PCR test undertaken for symptoms with longer anti-nucleocapsid half-lives.
SARS-CoV-2 anti-nucleocapsid antibodies wane within months and fall faster in younger adults and those without symptoms. However, anti-spike IgG remains stably detected. Ongoing longitudinal studies are required to track the long-term duration of antibody levels and their association with immunity to SARS-CoV-2 reinfection.
Pneumococcal pneumonia is concentrated among the elderly. Using a decision analytic model, we projected the future incidence of pneumococcal pneumonia and associated healthcare utilization and costs ...accounting for an aging US population. Between 2004 and 2040, as the population increases by 38%, pneumococcal pneumonia hospitalizations will increase by 96% (from 401 000 to 790 000), because population growth is fastest in older age groups experiencing the highest rates of pneumococcal disease. Absent intervention, the total cost of pneumococcal pneumonia will increase by $2.5 billion annually, and the demand for healthcare services for pneumococcal pneumonia, especially inpatient capacity, will double in coming decades.
•Included over 5 million members of Kaiser Permanente Northern California.•Determined direct health care costs for all of these individuals from 2003 to 2015.•Used residential Normalized Difference ...Vegetation Index (NDVI) satellite data to determine the green cover of each individual.•Conducted log-linear gamma generalized linear regression to determine the association between green cover and health care costs.•Living in areas of high green cover was inversely associated with total direct health care costs.
Prior studies have shown higher green cover levels are associated with beneficial health outcomes. We sought to determine if residential green cover was also associated with direct healthcare costs.
We linked residential Normalized Difference Vegetation Index (NDVI) satellite data for 5,189,303 members of Kaiser Permanente Northern California (KPNC) to direct individual healthcare costs for 2003–2015. Using generalized linear regression to adjust for confounding, we examined the association between direct healthcare costs and green cover within250, 500, and 1000 meters (m) of an individual’s residence. Costs were determined from an internal cost accounting system that captures administrative and patient care costs for each clinical encounter. Sensitivity analyses included adjustments for comorbidity and an alternative measure of green cover, tree canopy.
We observed a significant inverse association between higher levels of residential green cover and lower direct healthcare costs. The relative rate of total cost for the highest compared to the lowest decile of NDVI was 0.92 (95% CI 0.90–0.93) for the 500 m buffer. The association was robust to adjustment from a broad array of confounders, found at each buffer size, and largely driven by hospitalization, and emergency department visits. Individuals in the top decile of residential green cover had adjusted healthcare costs of $374.04 (95% CI $307.31-$439.41) per person per year less than individuals living in the bottom or least green decile. Sensitivity analyses including tree canopy cover as the green space measure yielded similar findings. Analyses that included adjustment for comorbidity were consistent with the hypothesis that green cover reduces healthcare costs by improving health status.
Green cover was associated with lower direct healthcare costs, raising the possibility that residential greening can have a significant healthcare cost impact across the population.
Delirium is a common, serious, and potentially preventable problem for older adults, associated with adverse outcomes. Coupled with its preventable nature, these adverse sequelae make delirium a ...significant public health concern; understanding its economic costs is important for policy makers and health care leaders to prioritize care.
To evaluate current 1-year health care costs attributable to postoperative delirium in older patients undergoing elective surgery.
This prospective cohort study included 497 patients from the Successful Aging after Elective Surgery (SAGES) study, an ongoing cohort study of older adults undergoing major elective surgery. Patients were enrolled from June 18, 2010, to August 8, 2013. Eligible patients were 70 years or older, English-speaking, able to communicate verbally, and scheduled to undergo major surgery at 1 of 2 Harvard-affiliated hospitals with an anticipated length of stay of at least 3 days. Eligible surgical procedures included total hip or knee replacement; lumbar, cervical, or sacral laminectomy; lower extremity arterial bypass surgery; open abdominal aortic aneurysm repair; and open or laparoscopic colectomy. Data were analyzed from October 15, 2019, to September 15, 2020.
Major elective surgery and hospitalization.
Cumulative and period-specific costs (index hospitalization, 30-day, 90-day, and 1-year follow-up) were examined using Medicare claims and extensive clinical data. Total inflation-adjusted health care costs were determined using data from Medicare administrative claims files for the 2010 to 2014 period. Delirium was rated using the Confusion Assessment Method. We also examined whether increasing delirium severity was associated with higher cumulative and period-specific costs. Delirium severity was measured with the Confusion Assessment Method-Severity long form. Regression models were used to determine costs associated with delirium after adjusting for patient demographic and clinical characteristics.
Of the 566 patients who were eligible for the study, a total of 497 patients (mean SD age, 76.8 5.1 years; 281 women 57%; 461 White participants 93%) were enrolled after exclusion criteria were applied. During the index hospitalization, 122 patients (25%) developed postoperative delirium, whereas 375 (75%) did not. Patients with delirium had significantly higher unadjusted health care costs than patients without delirium (mean SD cost, $146 358 $140 469 vs $94 609 $80 648). After adjusting for relevant confounders, the cumulative health care costs attributable to delirium were $44 291 (95% CI, $34 554-$56 673) per patient per year, with the majority of costs coming from the first 90 days: index hospitalization ($20 327), subsequent rehospitalizations ($27 797), and postacute rehabilitation stays ($2803). Health care costs increased directly and significantly with level of delirium severity (none-mild, $83 534; moderate, $99 756; severe, $140 008), suggesting an exposure-response relationship. The adjusted mean cumulative costs attributable to severe delirium were $56 474 (95% CI, $40 927-$77 440) per patient per year. Extrapolating nationally, the health care costs attributable to postoperative delirium were estimated at $32.9 billion (95% CI, $25.7 billion-$42.2 billion) per year.
These findings suggest that the economic outcomes of delirium and severe delirium after elective surgery are substantial, rivaling costs associated with cardiovascular disease and diabetes. These results highlight the need for policy imperatives to address delirium as a large-scale public health issue.