Trends in coronary mortality and community services, associated with occupational structure in New York State, 1980-96. (Research Report).

Study objective: Examine the association between county occupational structure, services availability, prevalence of risk factors, and coronary mortality rates by sex, for 1980-96, in New York state.

Design: New York's 62 counties were classified into three occupational structure categories; counties with the lowest percentages of the labour force in managerial, professional, and technical occupations were classified in category I, counties with the highest percentages were in category III. Directly age adjusted coronary heart disease (CHD) mortality rates, aged 35-64 years, (from vital statistics and census data), per capita services (Census County Business Patterns), and the prevalence of CHD risk factors (BRFSS data) were calculated for each occupational structure category.

Results: CHD mortality rates and the prevalence of risk factors were inversely associated with occupational structure for men and women. Income from manufacturing jobs declined most in category I and per capita numbers of producer services for banking, business credit, overall business services, and personnel/employment services were 9-15 times greater in category III compared with I counties. Consumer services such as grocery stores, fitness facilities, doctors offices, and social services were 1.5-4 times greater in category III compared with I counties.

Conclusions: An ecological model for conceptualising communities and health and for intervention design is discussed; key community characteristics are occupational and industrial structure, availability and diversity of consumer services, prevalence of health practices, and level of premature CHD.

**********

Occupational structure (that is, the set of jobs that exist in a community) is an aspect of the industrial structure and division of labour of a population and reflects the position of a local labour market in the larger state, national, and international economies. The occupational structure of United States counties is related to community economic resources and the availability and quality of local services including education, housing, transportation, recreation, and medical care. (1-5) The percentage of a county labour force in white collar jobs has been used as an indicator of occupational structure (2,3,4,6); an alternative indicator based on the percentage of "upper" white collar jobs (that is, managerial, supervisory, and technical/professional jobs) has more recently been used. (5) The percentage of a county labour force in "upper" white collar jobs was positively associated with local economic resources (for example, county tax base and expenditures) and the availability and diversity of local serv ices. (5) This included services relevant to cardiovascular health including per capita numbers of physical fitness facilities and grocery stores. Furthermore, county occupational structure was inversely associated with premature coronary heart disease (CHD) (2,4,5) and stroke mortality (3) and with the prevalence of risk factors such as overweight and exercise. (5)

In recent decades economies of the United States and other developed countries have experienced changes in industrial structure, such that percentages of total income and employment have declined for the goods manufacturing sector and the service sector has experienced steady and substantial growth. (7-11) Thus in the United States in 1992, 73% of total employment was in the service sector. (11) This has been described as de-industrialisation and this transformation has influenced both occupational structure in the United States and has had an impact on geographical distributions of economic resources and services in communities. (9,11,12) The service sector encompasses a wide range of activities involving, for example, taxicabs, radio and television broadcasting, gasoline stations, banks, schools, hotels and motels, child care, computer support, repair shops, libraries, legal and accounting services. A definition of service activities is further understood by distinguishing service activities from two other major industry sectors, manufacturing (that is, producing tangible goods) and extraction industries (that is, agriculture, forestry, fishing, mining).

Two broad categories of services that have implications for economic development and geographical distributions of jobs and economic resources, are consumer services and producer services. As implied, consumer services are rendered directly to people, whereas producer services are rendered to firms and represent business or commercial activity (services that appear in both categories may be distinguishable based on the source of the majority of their income). Government services (for example, social services) can represent a substantial contribution to the service sector, especially in countries with nationalised utilities and medical care. Government services are often categorised separately as they can potentially deter overall economic development when competition with privately owned services occurs. Consumer services are more apparently related to public health, for example, the availability and quality of fitness facilities, grocery stores, social services and medical care. However, producer services re late to public health by contributing to the strength of a local economy and the quality and availability of local jobs and wage levels, which indirectly supports the availability of consumer services. (11)

In a previous study in Washington state, an association was observed between county occupational structure, coronary mortality trends and the availability of community services in 1990. (5) This study expands on previous research by examining the association between occupational structure, coronary mortality trends, and community services in New York state, and by examining changes in services availability during 1980 to 1995. In addition, this study analyses additional types of services and discusses the relevance of producer services to public health, as these activities affect the availability and quality of jobs and the strength of a local economy, including the ability of the economy to support health related consumer services.

METHODS

The proportion of the civilian, employed labour force in selected white collar occupations (that is, managerial, professional speciality, and technical occupations) was used to represent the occupational structure of counties in New York state. Information on the proportion of each county labour force in managerial/professional occupations was obtained from the US Census of Population and Housing in 1980. This information was used to rank the 62 counties by the percentage of the labour force in managerial/professional occupations, and the range between the first and the 99th centiles of the distribution was divided into three occupational structure categories of equal ranges of percentages, which is consistent with previous studies. (2 4 5) Counties with percentages of managerial/professional workers below the first and above the 99th centiles of the distribution were included in categories I and III, respectively. Unlike categorisation by quantiles of numbers of counties, construction of the occupational str ucture categories based on equal divisions of the range of percentage of managerial! professional workers allows extrapolation of an observed pattern to the continuous variation in the occupational structure variable. Although the proportion of the labour force in the selected white collar occupations increased overall during the study period, the correlation between 1980 and 1990 distributions is 0.90, which indicates that the relative position of counties in the distribution was quite stable.

Mortality rates were calculated for New York residents, aged 35-64 years; this age group represents premature mortality (13) from CHD and permits comparisons of these results with previous analyses. Deaths with underlying causes assigned to ICD-9 codes (14) 410-414, 402, 429.2 were included as CHD deaths. Population counts were obtained from the US Bureau of Census. Annual CHD deaths and population counts for five year age groups, from 35-64 years, were summed within occupational structure categories. Annual age adjusted CHD mortality rates were calculated by gender and occupational structure category for 1980-96. Rates were calculated by the direct method using the 1970 US population as the standard. To improve the stability of annual mortality rates by occupational structure and gender, a three year moving average was used. For example, the annual rate for 1996, represents an average of observed rates for 1994-96, the rate for 1982, represents an average of observed rates for 1980-82, etc. As data for the calculation of rates represent complete death and population counts during the study period, statistical testing of mortality rates was not used. Furthermore, as all New York counties were included and were categorised rather …