CHRT Report Shows Patterns of Health Practice Vary Across Michigan

October 4, 2010 | Publication

A report released today by the Center for Healthcare Research & Transformation (CHRT) on the use of health care services in Michigan shows a high degree of variation in the use of certain tests and procedures—including back surgery, Cesarean section, hysterectomy, and angioplasty—among different regions throughout the state. The “Thumb”/Saginaw area had among the highest use rates for all procedures studied. The use of medication for pediatric attention-deficit/hyperactivity disorder (ADHD) also varied widely from region to region, with the Grosse Pointe, Grand Haven, and Kalamazoo areas having the highest reported rates in the study.

CHRTBook: Health Care Variation in Michigan compares the state’s Blue Cross commercially insured population to the Medicare population, and looks at changes within the commercial population in overall use and geographic variation over the past 10 years. It was modeled after the groundbreaking Dartmouth Atlas of Health Care study.

“Geographic variation has been well-documented nationally and was a significant topic of discussion during the debate on health reform,” said Marianne Udow Phillips, director, Center for Healthcare Research & Transformation. “Developing a better understanding of variation in the use of health care services could support state and national efforts to improve quality and contain costs in the health care system.”

The report depicts an improving picture in some key areas, showing notable reductions in overall use for some procedures often considered to be “over-utilized.” For example, while rates of coronary angiography and angioplasty procedures have increased nationally, they have decreased for Michigan’s Blue Cross commercial population. This improvement may be the result of a statewide cardiovascular quality collaborative, launched in 1996 by Blue Cross and hospitals throughout the state to improve safety and outcomes for patients undergoing angioplasty.

Highlights of findings in CHRTBook: Health Care Variation in Michigan include:

  • Blue Cross Blue Shield of Michigan use trends are better than national trends for high-cost interventional cardiac procedures. This may indicate that more heart patients are being successfully treated with medical options over interventional options.
  • In the Blue Cross Blue Shield of Michigan commercial population, hospital admission rates for conditions where all or part of the hospitalization could have been prevented (known as “ambulatory care sensitive conditions”) significantly decreased from an average of 71 admissions per 10,000 members in 1997, to an average of 36 admissions per 10,000 members in 2008.
  • The data show a direct correlation between diagnostic and interventional procedures. For example, areas with high rates of CT scans for low back pain also had high rates of back surgery.
  • Michigan, like the rest of the nation, is seeing a significant, unexplained increase in C-section rates. Every area in the state has increased its C-section rates over the last 10 years. More than one-third (34 percent) of all births covered by Blue Cross Blue Shield of Michigan were delivered by Cesarean section in 2008, a marked increase over 1997’s 22.9 percent. (The U.S. Department of Health and Human Services’ Healthy People 2010 goal was that no more than 12 percent of births should be from C-section.)
  • As in the 1997 Dartmouth Atlas study, there is considerable geographic variation in ADHD drug use rates for children in Michigan. There is no evidence to explain this variation.

“This study shows that we can make a difference on health care cost and quality through innovations such as the cardiovascular collaborative initiative,” says Thomas L. Simmer, MD, senior vice president and chief medical officer, Blue Cross Blue Shield of Michigan. “We’ll use the information in the report to further these collaborations for continuous improvement.”

“The variation we see in this report does not seem to be explained by health status or other relevant differences among the populations studied,” said Udow-Phillips. “This points to the need for further studies and more collaboration between payers and providers, both to determine optimal use rates—as in the case of ADHD drugs—and to better understand the drivers behind the variation we see in the use of these procedures and to reduce unexplained variation.”