Najlla Nassery

The state of overuse measurement: A critical review.:

Health care overuse contributes to unnecessary expenditures and patient exposure to harm. Understanding and addressing this problem requires a comprehensive set of valid metrics. This article describes and critiques the current state of overuse measurement through a review of the published and gray literature, measures clearinghouses and ongoing work by major measure developers. Our review identified 37 fully specified measures and 123 measurement development opportunities. Many services were considered overuse due to the extension of diagnostic or screening services to low-risk populations. There were more diagnostic or therapeutic overuse measures than for screening or monitoring/surveillance. Imaging services is a major focus of current measures, but opportunities exist to expand overuse measurement in medication, laboratory services. Future development of overuse measures would benefit from new empirical research and clinical guidelines focused on identifying indications or populations for which there is likely to be no or low benefit.

Identifying possible indicators of systematic overuse of health care procedures with claims data.

Background:Health care quality is frequently described with measures representing the overall performance of a health care system. Despite the growing attention to overuse of health care resources, there is little experience with aggregate measures of overuse. Objective:To identify a set of possible indicators of overuse that can be operationalized with claims data and to describe variation in these indicators across the hospital referral regions (HRRs). Design:Using an environmental scan, we identified published descriptions of overused procedures. We assessed each procedure’s feasibility for measurement with claims and developed algorithms for occurrences of procedures in patients unlikely to benefit. Using a 5% sample of Medicare claims from 2008, we calculated summary statistics to illustrate variance in the use across HRRs. Results:A total of 613 procedures were identified as overused; 20 had abundant frequency and variance to be possible measures of systematic overuse. These included 13 diagnostic tests, 2 tests for screening, 1 for monitoring, and 4 therapeutic procedures. The usage varied markedly across HRRs. For illustration, 1 HRR used computed tomography for rhinosinusitis diagnosis in 80 of 1000 beneficiaries (mean usage across HRRs was 14/1000). Among 1,451,142 beneficiaries, 14% had at least one overuse event (range, 8.4%–27%). Conclusions:We identified a set of overused procedures that may be used as measures of overuse and that demonstrate significant variance in their usage. The implication is that an index of overuse might be built from these indicators that would reveal systematic patterns of overuse within regions. Alternatively, these indicators may be valuable in the quality improvement efforts.

Systematic Overuse of Healthcare Services: A Conceptual Model

A perfect storm of factors influences the overuse of healthcare services in the USA. Considerable attention has been placed on geographic variation in utilization; however, empiric data has shown that geographic variation in utilization is not associated with overuse. While there has been renewed interest in overuse in recent years, much of the focus has been on the overuse of individual procedures. In this paper we argue that overuse should be thought of as a widespread and pervasive phenomenon that we coin as systematic overuse. While not directly observable (i.e., a latent phenomenon), we suggest that systematic overuse could be identified by tracking a portfolio of overused procedures. Such a portfolio would reflect systematic overuse if it is associated with higher healthcare costs and no health benefit (including worse health outcomes) across a healthcare system. In this report we define and conceptualize systematic overuse and illustrate how it can be identified and validated via a simple empirical example using several Choosing Wisely indicators. The concept of systematic overuse requires further development and empirical verification, and this paper provides an important first step, a conceptual framework, to that end.

An index for measuring overuse of health care resources with medicare claims

Background:Overuse can be defined as use of a service when the risk of harm exceeds its likely benefit. Yet, there has been little work with composite measures of overuse. Objective:Our goal was to create a composite measure of overuse with claims data. Design:Observational study using 5% of Medicare claims from 2008. Setting:All inpatient and outpatient settings of care, excluding nursing homes. Participants:Older Americans receiving health care services in hospitals or outpatient settings. Measures:We applied algorithms to identify specific cases of overuse across 20 previously identified procedures and used multilevel modeling techniques to examine variation in overuse across all procedures. Included in the model were patient-level factors and both procedure and regional fixed effects for the 306 hospital referral regions (HRR). These estimated regional fixed effects, representing the systematic, region variation in overuse across all measures, was then normalized compared with the overall average to generate a Z score for each HRR. The resulting “Overuse Index” was then compared with total costs, 30-day postdischarge mortality, and total mortality at the HRR level, graphically, and associations were tested using Spearman &rgr;. Results:The Overuse Index varied markedly across regions, but 23 were higher than the average (P<0.05). The Index was positively associated with total costs (&rgr;=0.28, P<0.0001). It was positively correlated with 30-day postdischarge mortality (&rgr;=0.18 P⩽0.005), and neither positively or negatively correlated with total mortality. Conclusions:This study confirms previous research hypothesizing that systematic regional variation in overuse exists and is measurable. Addition research is needed to validate index and to test its predictive and concurrent validity in panel data.

Association between serotonin denervation and resting‐state functional connectivity in mild cognitive impairment

Resting‐state functional connectivity alterations have been demonstrated in Alzheimers disease (AD) and mild cognitive impairment (MCI) before the observation of AD neuropathology, but mechanisms driving these changes are not well understood. Serotonin neurodegeneration has been observed in MCI and AD and is associated with cognitive deficits and neuropsychiatric symptoms, but the role of the serotonin system in relation to brain network dysfunction has not been a major focus of investigation. The current study investigated the relationship between serotonin transporter availability (SERT; measured using positron emission tomography) and brain network functional connectivity (measured using resting‐state functional MRI) in 20 participants with MCI and 21 healthy controls. Two SERT regions of interest were selected for the analysis: the Dorsal Raphe Nuclei (DRN) and the precuneus which represent the cell bodies of origin and a cortical target of projections of the serotonin system, respectively. Both regions show decreased SERT in MCI compared to controls and are the site of early AD pathology. Average resting‐state functional connectivity did not differ between MCI and controls. Decreased SERT in DRN was associated with lower hippocampal resting‐state connectivity in MCI participants compared to controls. Decreased SERT in the right precuneus was also associated with lower resting‐state connectivity of the retrosplenial cortex to the dorsal lateral prefrontal cortex and higher resting‐state connectivity of the retrosplenial cortex to the posterior cingulate and in patients with MCI but not in controls. These results suggest that a serotonergic mechanism may underlie changes in brain functional connectivity in MCI. Hum Brain Mapp 38:3391–3401, 2017.

Molecular imaging of serotonin degeneration in mild cognitive impairment

Neuropathological and neuroimaging studies have consistently demonstrated degeneration of monoamine systems, especially the serotonin system, in normal aging and Alzheimers disease. The evidence for degeneration of the serotonin system in mild cognitive impairment is limited. Thus, the goal of the present study was to measure the serotonin transporter in vivo in mild cognitive impairment and healthy controls. The serotonin transporter is a selective marker of serotonin terminals and of the integrity of serotonin projections to cortical, subcortical and limbic regions and is found in high concentrations in the serotonergic cell bodies of origin of these projections (raphe nuclei). Twenty-eight participants with mild cognitive impairment (age 66.6±6.9, 16 males) and 28 healthy, cognitively normal, demographically matched controls (age 66.2±7.1, 15 males) underwent magnetic resonance imaging for measurement of grey matter volumes and high-resolution positron emission tomography with well-established radiotracers for the serotonin transporter and regional cerebral blood flow. Beta-amyloid imaging was performed to evaluate, in combination with the neuropsychological testing, the likelihood of subsequent cognitive decline in the participants with mild cognitive impairment. The following hypotheses were tested: 1) the serotonin transporter would be lower in mild cognitive impairment compared to controls in cortical and limbic regions, 2) in mild cognitive impairment relative to controls, the serotonin transporter would be lower to a greater extent and observed in a more widespread pattern than lower grey matter volumes or lower regional cerebral blood flow and 3) lower cortical and limbic serotonin transporters would be correlated with greater deficits in auditory-verbal and visual-spatial memory in mild cognitive impairment, not in controls. Reduced serotonin transporter availability was observed in mild cognitive impairment compared to controls in cortical and limbic areas typically affected by Alzheimers disease pathology, as well as in sensory and motor areas, striatum and thalamus that are relatively spared in Alzheimers disease. The reduction of the serotonin transporter in mild cognitive impairment was greater than grey matter atrophy or reductions in regional cerebral blood flow compared to controls. Lower cortical serotonin transporters were associated with worse performance on tests of auditory-verbal and visual-spatial memory in mild cognitive impairment, not in controls. The serotonin system may represent an important target for prevention and treatment of MCI, particularly the post-synaptic receptors (5-HT4 and 5-HT6), which may not be as severely affected as presynaptic aspects of the serotonin system, as indicated by the observation of lower serotonin transporters in MCI relative to healthy controls.