Adults with diabetes tend to have higher age-adjusted mortality rates (1,2). Evidence from Britain (3) suggests that mortality in diabetic adults is inversely related to socioeconomic status. The importance of self-care and blood glucose control in adults with diabetes suggests that education may be an important factor in long-term health outcomes, a hypothesis that is also consistent with evidence in the health economics literature that education increases the efficiency of investment in health (4,5). The specific hypothesis tested here is that mortality in adults with diabetes is inversely related to education.

The data are taken from the National Health Interview Survey (NHIS) of 1989, including its diabetes supplement, with mortality status taken from the NHIS Multiple Cause of Death Public Use Data File, including deaths from 1989 to 1995. The statistical analysis is applied to those adults who self-reported that they had been diagnosed with diabetes, excluding those with apparent type 1 diabetes (age of onset <30 years, with insulin dependence, and a BMI <27.2 kg/m2 for men and <26.9 for women). The resulting sample includes 2,387 adults with type 2 diabetes having an average age of 61.8 years.

Logistic regression analysis is used to explore the relation between mortality and educational attainment, family income (greater than or less than $20,000 per year in 1989), age, sex, marital status, race, and duration of diabetes. The statistical analysis is carried out with the svylogit procedure in STATA software, version 7 (STATA, College Station, TX), using the NHIS sampling weights.

The primary finding is that mortality is inversely related to education for diabetic adults (OR [95% CI] 0.61 [0.40–0.93] for college graduation or higher and 0.78 [0.61–0.99] for high school graduation or higher). Mortality is not significantly related to family income, marital status, or race, but age, male sex, and duration of diabetes have the expected positive and statistically significant associations with mortality. The finding that education reduces the mortality risk of diabetic adults is consistent with the predictions from health investment theory that education increases the efficiency of health investment. Education may also be a factor in the relatively poor health status and outcomes of adults with diabetes (6).

The author thanks Philip Jacobs for comments, Glenn Harrison for generous help with the data, and Paula Veiga for expert research assistance. Any remaining errors are mine.

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Harris MI: Health care and health status and outcomes for patients with type 2 diabetes.
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Address correspondence to Ronald P. Wilder, PhD, Department of Economics, Moore School of Business, University of South Carolina, Columbia, SC 29208. E-mail: [email protected].

DIABETES CARE
2003