Andrew Coco, MD Jeff Martin, MD FMEC November 1, 2013

 A 58-year-old Maryland woman breaks her ankle, develops a blood clot and, unable to find a doctor to monitor her blood-thinning drug, winds up in an emergency room 30 times in six months.  A 55-year-old Mississippi man with severe hypertension and kidney disease is repeatedly hospitalized for worsening heart and kidney failure; doctors don't know that his utilities have been disconnected, leaving him without air conditioning or a refrigerator in the sweltering summer heat.

Illustration by Alex Nabaum/For The Washington Post and KHN

 These patients are among the 1 percent whose ranks no one wants to join: the costly cohort battling multiple chronic illnesses who consumed 21 percent of the nearly $1.3 trillion Americans spent on health care in 2010, at a cost of nearly $88,000 per person.  Agency for Healthcare Research and Quality.

 Patients with frequent ED visits are often portrayed as unscrupulous, uninsured, and unnecessarily clogging EDs by presenting with primary care complaints better treated elsewhere.  Abelson R. Uninsured put a strain on hospitals. The New York Times. December 8,  Quinines S. Saving the ER for real emergencies: costly "frequent fliers" are being encouraged to visit clinics in LA. Los Angeles Times. January 22, 2007.

 Widely held assumptions about the patient population who frequently visits EDs, and their reasons for visiting, have not been, for the most part, supported by research on the topic.  Although the practicing provider may regularly encounter the stereotypical frequent ED user, this snapshot may not accurately reflect the true nature of frequent ED use

 About 79.7% of adults visited the emergency room due to lack of access to other providers, significantly more than the 66.0% who visited due to seriousness of the medical problem.  The most common reasons for the last emergency room visit were: only a hospital could help (54.5%), the doctor's office was not open (48.0%), or there was no other place to go (46.3%).

 Uninsured adults were more likely to visit the emergency room because they had no other place to go at the time of the last visit (61.6%), compared with adults having private insurance (38.9%) or those with public health plan coverage (48.5%)  Uninsured adults were significantly less likely to visit the emergency room because the doctor’s office was not open at the time of their last visit (30.9%) than adults with private insurance (49.9%) or those with public health plan coverage (59.7%)

 Frequent ED use occurs even in a coordinated health care system that provides ready access to outpatient care. Frequent ED users are characterized by traits that represent high levels of psychosocial and medical needs.  On a societal level, our findings support recent research suggesting that improved health outcomes may be realized through increasing expenditures for social services such as housing subsidies and income supplements  Doran KM et al. National VNA ED study. Ann Emerg Med. Feb 2013

 Are frequent visitors coming to the ED due to lack of primary care access, for convenience, or because of lack of social services?  The objective of this study is to inform policy development, from a national perspective, directed at frequent ED users and to highlight potential challenges in attending to their healthcare needs.

 Data for this study was compiled from the National Hospital Ambulatory Medical Care Survey (NHAMCS). The survey is administered by the National Center for Health Statistics (NCHS) for the CDC. It is designed to meet the need for objective, reliable information about ambulatory medical care services in hospital outpatient and emergency departments in the United States.

 Using a 4-stage probability sample design, NHAMCS collects a nationally representative sample of all visits emergency departments excluding federal hospitals.  NHAMCS data is collected by hospital staff members and monitored by field representatives.  Visit information is collected during a randomly assigned 4-week reporting period. The basic sampling unit used throughout the survey is the visit, not the patient.

 This paper utilizes the statistical theory of using a multiplicity estimator to create estimates about patients from encounter, or visit, data. Multiplicity occurs when the same observation unit (e.g. the patient) can be counted multiple times among the selection units (e.g. the patient visits).

 Based on statistical techniques developed at the National Center for Healthcare Statistics, it is possible to re-weight standard provider- based medical encounter data to yield patient estimates using a multiplicity estimator and appropriate network information obtained in the survey to account for multiple visits by the patient to the same emergency department

 139,502 ED visits over the 4 year period  Representing 397,165,016 visits nationally  84,630 visits (61%) had information on number visits in past 12 months.  5,131 visits represented those patients with 6 or more visits in the past 12 months – the top 1% of utilizers.

 abdominal pain  headache  spondylosis; intervertebral disc  superficial injury; contusion  non specific chest pain  sprains and strains  other respiratory infection  urinary tract infections  COPD  other nervous system disorders

 Contusion  sprains/strains  other respiratory infection  abdominal pain  non specific chest pain  other injuries/conditions  open wounds of extremities  skin and subcutaneous infection  spondylosis, intervetebral disc  open wounds of head, neck trunk

 Ambulatory care-sensitive conditions are conditions for which good outpatient care can potentially prevent the need for hospitalization, or for which early intervention can prevent complications of more severe disease.  Developed by AHRQ as one of their quality indicators.

 Bacterial pneumonia  Dehydration  Urinary tract infections  Perforated appendix  Low birth weight  Angina without procedure  Congestive heart failure  Hypertension  Adult asthma  Chronic obstructive pulmonary disease  Uncontrolled diabetes  Diabetes, short-term complications  Diabetes, long-term complications  Lower extremity amputations among patients with diabetes

 13 % of patients with 6 or more visits in the past year had an ambulatory sensitive condition compared to 9% with less frequent visits. P <.001  When controlled for all other significant variables in regression model, frequent ED visitors were 30% more likely to have an ambulatory care sensitive condition.

 Visit data, not patient data.  39% of visits did not have information on number of visits in past year so sensitivity analysis needed to show comparability with rest of database.

 Frequent ED use is probably multi-factorial  Higher rate of ambulatory care sensitive conditions could indicate primary care access issue  Higher rate of pain diagnoses and uninsured could support some of the assumptions of convenience use  Higher rate of homelessness and lack of transportation could indicate social service deficiencies.

Learning Institute Sessions Give Data Users First-Hand Experience This year’s Learning Institute featured 16 hands- on session, and 5 lecture sessions on NCHS surveys and resources. Both beginner and advanced sessions were available for the National Ambulatory Medical Care Survey (NAMCS), the National Hospital Ambulatory Medical Care Survey (NHAMCS), and the National Health Interview Survey (NHIS).