The Effect of Influenza Vaccination for the Elderly on Hospitalization and Mortality: An Observational Study With a Regression Discontinuity Design.

Background: Observational studies using traditional research designs suggest that influenza vaccination reduces hospitalizations and mortality among elderly persons. Accordingly, health authorities in some countries prioritize vaccination of this population. Nevertheless, questions remain about this policy's effectiveness given the potential for bias and confounding in observational data. Objective: To determine the effectiveness of the influenza vaccine in reducing hospitalizations and mortality among elderly persons by using an observational research design that reduces the possibility of bias and confounding. Design: A regression discontinuity design was applied to the sharp change in vaccination rate at age 65 years that resulted from an age-based vaccination policy in the United Kingdom. In this design, comparisons were limited to individuals who were near the age-65 threshold and were thus plausibly similar along most dimensions except vaccination rate. Setting: England and Wales. Participants: Adults aged 55 to 75 years residing in the study area during 2000 to 2014. Intervention: Seasonal influenza vaccine. Measurements: Hospitalization and mortality rates by month of age. Results: The data included 170 million episodes of care and 7.6 million deaths. Turning 65 was associated with a statistically and clinically significant increase in rate of seasonal influenza vaccination. However, no evidence indicated that vaccination reduced hospitalizations or mortality among elderly persons. The estimates were precise enough to rule out results from many previous studies. Limitation: The study relied on observational data, and its focus was limited to individuals near age 65 years. Conclusion: Current vaccination strategies prioritizing elderly persons may be less effective than believed at reducing serious morbidity and mortality in this population, which suggests that supplementary strategies may be necessary. Primary Funding Source: National Institute on Aging.

The Economic Consequences of Hospital Admissions.

We use an event study approach to examine the economic consequences of hospital admissions for adults in two datasets: survey data from the Health and Retirement Study, and hospitalization data linked to credit reports. For non-elderly adults with health insurance, hospital admissions increase out-of-pocket medical spending, unpaid medical bills, and bankruptcy, and reduce earnings, income, access to credit, and consumer borrowing. The earnings decline is substantial compared to the out-of-pocket spending increase, and is minimally insured prior to age-eligibility for Social Security Retirement Income. Relative to the insured non-elderly, the uninsured non-elderly experience much larger increases in unpaid medical bills and bankruptcy rates following a hospital admission. Hospital admissions trigger fewer than 5 percent of all bankruptcies in our sample.

The Economic Consequences of Hospital Admissions.

We use an event study approach to examine the economic consequences of hospital admissions for adults in two datasets: survey data from the Health and Retirement Study, and hospitalization data linked to credit reports. For non-elderly adults with health insurance, hospital admissions increase out-of-pocket medical spending, unpaid medical bills and bankruptcy, and reduce earnings, income, access to credit and consumer borrowing. The earnings decline is substantial compared to the out-of-pocket spending increase, and is minimally insured prior to age-eligibility for Social Security Retirement Income. Relative to the insured non-elderly, the uninsured non-elderly experience much larger increases in unpaid medical bills and bankruptcy rates following a hospital admission. Hospital admissions trigger less than 5 percent of all bankruptcies.

The Mechanisms of Alcohol Control.

A substantial economics literature documents that tighter alcohol controls reduce alcohol-related harms, but far less is known about mechanisms. We use the universe of Canadian mortality records to document that Canada's Minimum Legal Drinking Age (MLDA) significantly reduces mortality rates of young men but has much smaller effects on women. Using drinking data that are far more detailed than in prior work, we document that the MLDA substantially reduces 'extreme' drinking among men but not women. Our results suggest that alcohol control efforts targeting young adults should focus on reducing extreme drinking behavior.

The Minimum Legal Drinking Age and Crime.

We use variation from the minimum legal drinking age to estimate the causal effect of access to alcohol on crime. Using a census of arrests in California and a regression discontinuity design, we find that individuals just over age 21 are 5.9% more likely to be arrested than individuals just under 21. This increase is mostly due to assaults, alcohol-related offenses, and nuisance crimes. These results suggest that policies that restrict access to alcohol have the potential to substantially reduce crime.

Confirmation of the cellular targets of benomyl and rapamycin using next-generation sequencing of resistant mutants in S. cerevisiae.

Investigating the mechanisms of action (MOAs) of bioactive compounds and the deconvolution of their cellular targets is an important and challenging undertaking. Drug resistance in model organisms such as S. cerevisiae has long been a means for discovering drug targets and MOAs. Strains are selected for resistance to a drug of interest, and the resistance mutations can often be mapped to the drug's molecular target using classical genetic techniques. Here we demonstrate the use of next generation sequencing (NGS) to identify mutations that confer resistance to two well-characterized drugs, benomyl and rapamycin. Applying NGS to pools of drug-resistant mutants, we develop a simple system for ranking single nucleotide polymorphisms (SNPs) based on their prevalence in the pool, and for ranking genes based on the number of SNPs that they contain. We clearly identified the known targets of benomyl (TUB2) and rapamycin (FPR1) as the highest-ranking genes under this system. The highest-ranking SNPs corresponded to specific amino acid changes that are known to confer resistance to these drugs. We also found that by screening in a pdr1Δ null background strain that lacks a transcription factor regulating the expression of drug efflux pumps, and by pre-screening mutants in a panel of unrelated anti-fungal agents, we were able to mitigate against the selection of multi-drug resistance (MDR) mutants. We call our approach "Mutagenesis to Uncover Targets by deep Sequencing", or "MUTseq", and show through this proof-of-concept study its potential utility in characterizing MOAs and targets of novel compounds.

The minimum legal drinking age and public health.

The Amethyst Initiative, signed by more than 100 college presidents and other higher education officials calls for a reexamination of the minimum legal drinking age in the United States. A central argument of the initiative is that the U.S. minimum legal drinking age policy results in more dangerous drinking than would occur if the legal drinking age were lower. A companion organization called Choose Responsibility explicitly proposes "a series of changes that will allow 18-20 year-olds to purchase, possess and consume alcoholic beverages." Does the age-21 drinking limit in the United States reduce alcohol consumption by young adults and its harms, or as the signatories of the Amethyst Initiative contend, is it "not working"? In this paper, we summarize a large and compelling body of empirical evidence which shows that one of the central claims of the signatories of the Amethyst Initiative is incorrect: setting the minimum legal drinking age at 21 clearly reduces alcohol consumption and its major harms. We use a panel fixed effects approach and a regression discontinuity approach to estimate the effects of the minimum legal drinking age on mortality, and we also discuss what is known about the relationship between the minimum legal drinking age and other adverse outcomes such as nonfatal injury and crime. We document the effect of the minimum legal drinking age on alcohol consumption and estimate the costs of adverse alcohol-related events on a per-drink basis. Finally we consider implications for the correct choice of a minimum legal drinking age.

DOES MEDICARE SAVE LIVES?

Health insurance characteristics shift at age 65 as most people become eligible for Medicare. We measure the impacts of these changes on patients who are admitted to hospitals through emergency departments for conditions with similar admission rates on weekdays and weekends. The age profiles of admissions and comorbidities for these patients are smooth at age 65, suggesting that the severity of illness is similar on either side of the Medicare threshold. In contrast, the number of procedures performed in hospitals and total list charges exhibit small but statistically significant discontinuities, implying that patients over 65 receive more services. We estimate a nearly 1-percentage-point drop in 7-day mortality for patients at age 65, equivalent to a 20% reduction in deaths for this severely ill patient group. The mortality gap persists for at least 9 months after admission.

The War on Drugs: Methamphetamine, Public Health, and Crime.

In mid-1995, a government effort to reduce the supply of methamphetamine precursors successfully disrupted the methamphetamine market and interrupted a trajectory of increasing usage. The price of methamphetamine tripled and purity declined from 90 percent to 20 percent. Simultaneously, amphetaminerelated hospital and treatment admissions dropped 50 percent and 35 percent, respectively. Methamphetamine use among arrestees declined 55 percent. Although felony methamphetamine arrests fell 50 percent, there is no evidence of substantial reductions in property or violent crime. The impact was largely temporary. The price returned to its original level within four months; purity, hospital admissions, treatment admissions, and arrests approached preintervention levels within eighteen months. (JEL I12, K42).

The Effect of Alcohol Consumption on Mortality: Regression Discontinuity Evidence from the Minimum Drinking Age.

We estimate the effect of alcohol consumption on mortality using the minimum drinking age in a regression discontinuity design. We find large and immediate increases in drinking at age 21, including a 21 percent increase in recent drinking days. We also find a discrete 9 percent increase in the mortality rate at age 21, primarily due to motor vehicle accidents, alcohol-related deaths, and suicides. We estimate a 10 percent increase in the number of drinking days for young adults results in a 4.3 percent increase in mortality. Our results suggest policies that reduce drinking among young adults can have substantial public health benefits. (JEL I12, I18).

The Impact of Nearly Universal Insurance Coverage on Health Care Utilization: Evidence from Medicare.

The onset of Medicare eligibility at age 65 leads to sharp changes in the health insurance coverage of the U.S. population. These changes lead to increases in the use of medical services, with a pattern of gains across socioeconomic groups that varies by type of service. While routine doctor visits increase more for groups that previously lacked insurance, hospital admissions for relatively expensive procedures like bypass surgery and joint replacement increase more for previously insured groups that are more likely to have supplementary coverage after 65, reflecting the relative generosity of their combined insurance package under Medicare.

The incremental inpatient costs associated with marijuana comorbidity.

In this paper we examine the incremental cost of marijuana comorbidity for alcohol, mood and thought diagnoses in hospital settings. We use data from the 1993-2000 National Hospital Discharge Survey to examine the effect on length of stay and the 1995-2000 Florida Hospital Discharge Data to examine charges. General linear modeling (GLM) and propensity score methods are employed to deal with concerns stemming from the distribution of the dependent variables and statistically significant differences in the baseline characteristics of marijuana users versus non-users. Marijuana comorbidity is associated with longer length of stays and higher charges for patients suffering from a primary diagnosis of an alcohol problem. We also find higher average charges for patients suffering from mood disorders, though the finding is not robust across all model specifications. We do not find any significant effects for thought disorders. Findings from this study suggest that a marijuana comorbidity increases the cost of treating patients with alcohol problems and mood disorder diagnoses, implying that there may be real health consequences associated with marijuana abuse and dependence and more work considering this possibility is warranted.

Welfare leavers' use of Medicaid transitional medical assistance in California, 1993-1997.

Using administrative and survey data, we estimate participation rates in Transitional Medical Assistance (TMA) for the period 1993-97 by California welfare leavers during their first six months post-welfare. We find that although many welfare leavers were eligible for TMA (35% to 47% of exiters), only 26% of eligible people were enrolled in the TMA program. Another 14% were covered by non-TMA Medicaid for the entire six months. Most TMA-eligible exiters had Medicaid coverage (all of it non-TMA) for less than six months (49%) or no Medicaid coverage at all (11%). Supplementary analyses using data from the National Survey of America's Families indicate that if fully implemented, TMA could have substantially reduced uninsurance among welfare leavers.