Knox County, with its estimated 41,000 inhabitants, has the highest incidence of melanoma among all counties in Maine, a high incidence of female breast cancer, and the highest percentage of individuals reporting ever being diagnosed with cancer. It also has a high rate of arthritis, as well as hepatitis C.

On a brighter side, its citizens have a lower prevalence of heart disease, asthma and diabetes than other areas of the state. And, its mortality rate from all cancers, while high compared to the national and state percentage, is less than other counties.

The numbers are part of a landmark health care assessment that looks not just at disease rates within each county, but the health care pluses, such as low hospitalization rates for diabetes, and low emergency department visit rates for mental health and substance abuse problems, as in the case of Knox County.

This month, the three major nonprofit health care organizations in Maine issued their 262-page report, “OneMaine Community Health Needs Assessment 2010.” The $400,000 project OneMaine Health is a collaboration between Eastern Maine Healthcare Systems, MaineGeneral Health and MaineHealth, the parent company of Pen Bay Medical Center, Pen Bay Health Care organizations, Waldo County General and Miles Memorial hospitals. Costs for the assessment were split between the three nonprofits, with Eastern Maine and MaineHealth each picking up 42.5 percent and Maine General 15 percent. The assessment compiled data beginning more than a year ago, assisted by the University of Southern Maine and the company Market Decisions, Inc., of Portland.

“The three health systems that cover much of the state have done these assessments individually in the past, but there was no comparability in terms of methodology,” said Deborah Deatrick, vice president of community health for MaineHealth in Portland. “The problem was, you could not compare methods across the state. This helps develop an approach that is the same for every county. This assessment will be replicated every five years.”

Pen Bay Healthcare is working with MaineHealth to coordinate an interactive community forum on the results of the report, as well as its strategic goals to address statewide health needs, and those of Knox County, said Megan Williams, spokeswoman for Pen Bay Healthcare.

“The co-directors of the Picker Family Resource Center, Linda Zeigler and Wendelanne Augunas are aiming to hold the forum in late spring or early summer,” she said.

The report includes results of surveys returned by 7,099 Maine residents, who were asked about their health conditions and habits, and are combined with other Maine health statistics, including records of hospital admissions, and centers for disease control, labor and census data. The assessment was designed to “identify the most important health issues in the state, both overall and by county, using scientifically valid health indicators and comparative information.”

Like the rest of the state, Knox County is aging. All Maine counties contain a disproportionately elderly population, relative to other age demographics, the report said.

“Maine is currently the oldest state in the U.S., with a median age of 42.2, well above the U.S. median age of 36.5, according to the report. The counties with the highest proportion of people age 65 and older are in the north and east, with Lincoln (19 percent), Aroostook (18), Knox (18), Washington (18), Piscataquis (18), and Hancock (17) all well above the state percentage of 15 percent. All Maine counties have a greater percentage of residents 65 years and older compared to the national percentage of 12.9 percent.”

“The proportion of youths under the age of 18 is also under the national average (24 percent), both statewide (21), and per Maine county. The counties with the lowest percentage are Knox, Lincoln, and Hancock, all with 19 percent,” the report said.

Across Maine, with a population of 1.3 million, there are significant and common health issues: The smoking rate hovers at 22 percent, leveling off from previous declines, and obesity combined with a sedentary lifestyle continues to pull on health care. Hospital admission rates for strokes are high statewide, while high blood pressure and high cholesterol, asthma, diabetes, asthma and respiratory illness are chronic.

And cancer is prevalent.

“Maine continues to have among the highest age-adjusted cancer incidence and mortality rates in the U.S.,” the report said. “In 2007, Maine’s age-adjusted cancer incidence rate (515 cases per 100,000 population) was the highest in the nation. Further, while U.S. incidence rates have been declining in recent years, Maine’s rates have remained high.”

Reasons for the high rates are unclear, the report said, “but may be a reflection of improved screening rates.”

It is hard, the report admits, to specifically determine why the cancer rates are high, but behavioral risk factors, such as smoking, poor nutrition and obesity are likely some of the reasons, as well as heredity, income and other social-demographic factors.

In Knox County, the rate of individuals reporting being diagnosed with cancer is 9.6 percent, while the state percentage is 7.5 percent. The county reported 39 out of 100,000 people with melanoma, while the statewide percentage is 26 percent. And, while the rate of female breast cancer is 3.8 percent across Maine, in Knox County the rate is 5.7 percent.

“We do not currently know enough why Maine experiences such high rates of cancer incidence, even when age is controlled for,” the report said. “We recommend that the state undertake a major epidemiological and policy study to guild planning and intervention to address this issue.”

But Knox County has a lower prevalence of heart disease, 5.5 percent to the state’s 6.3 percent, as well as a lower prevalence of adult asthma, diabetes, bladder and cervical cancers, and infectious diseases, excepting hepatitis C.

Knox County residents also go to the dentist more than those in other counties, and smokes less (18 percent as opposed to the statewide 22 percent), and its babies are born healthier and more at term than elsewhere in the state.

In Maine, alcohol remains the common substance to abuse, with binge and heavy drinking rates of respective 15 and 6 percent comparable to national averages. There is a high percentage of chronic heavy drinking in Knox County, particularly among those 65 and older. And, there is a high percentage of those reporting a problem with substance abuse at some point in their lives, 7.3 percent to the 4.7 statewide figure.

Interpersonal violence rates are high, as well, and there is a high teen birth rate in the county.

Mental health and substance abuse affects the population, with close to 11 percent of state residents saying they experience 11 or more days a month in which their mental health was not good. More than 7 percent are at risk of clinical depression, and 22 percent have been diagnosed with depression at some point in their lives, and 15 percent have a current such diagnosis.

Currently, the health care industry is the largest employment sector in Maine, with approximately 84,200 positions in 2008. Nursing and residential care positions account for the majority of health care employment in Maine – much higher than the national percentage — due primarily to the high ratio of elderly patients.

The report said that while Maine compares favorably with the rest of the country in many socioeconomic measures, many of the northern counties are not doing as well in these measures as their southern counterparts.

Maine is a well-educated state.

The most economically prosperous regions are the coastal counties of York, Cumberland, Sagadahoc, Lincoln, and Hancock. These counties all have comparatively low unemployment, low poverty rates, and high educational attainment.

The number of residents living below the federal poverty line varies from county to county. However, the northern and central counties in general have greater proportions of poverty stricken populations than southern coastal counties.

The report makes a series of recommendations, including better access to health care and dental care for all citizens, improving quality of care and preventative resources, and improving mental health services and substance abuse care.