Gopinath B, Rochtchina E, Flood VM, Mitchell P. Healthy Living and Risk of Major Chronic Diseases in an Older Population. Arch Intern Med. 2010;170(2):208-209. doi:10.1001/archinternmed.2009.500
A recent article in the Archives1 examined the extent to which 4 healthy lifestyle factors and their combinations were associated with reduced risk of developing chronic diseases. In the European Prospective Investigation Into Cancer and Nutrition (EPIC)-Potsdam study, compared with participants with no healthy factors, those with all 4 healthy factors had reductions of 93% (95% confidence interval [CI], 88% to 95%) for diabetes (P value for linear trend, <.001); 81% (95% CI, 47% to 93%) for myocardial infarction (MI) (P value for linear trend, <.001); 50% (95% CI, −18% to 79%) for stroke (P value for linear trend, .054); and 36% (95% CI, 5% to 57%) for cancer (P value for linear trend, <.001). As suggested by Ford et al,1 further studies in other populations are needed to evaluate the extent to which chronic disease may be potentially preventable. We investigated whether adhering to the 4 healthy lifestyle factors detailed in the EPIC-Potsdam study influenced the risk of developing incident diabetes, MI, and stroke in an older Australian population.
The Blue Mountains Eye Study (BMES-1) is a population-based cohort study of sensory loss and other health outcomes, with methods previously reported.2 During 1992 to 1994, 3654 participants 49 years or older were examined (82.4% participation). At the 5-year follow-up examinations (BMES-2), 2335 surviving participants (75.1% of survivors; 543 had died) were examined. Of the 2335 survivors in the BMES-2, 1952 (75.6% of survivors; 1103 persons died) were re-examined at the 10-year follow-up examinations (BMES-3).
Incident disease outcomes were assessed using the same definitions as in the EPIC-Potsdam report.1 Similarly, we used the same 4 healthy factors and methods to form an index ranging from 0 to 4, as detailed by Ford et al.1 However, because our physical activity measures were not available in hours per week, we included a definition of engaging in physical activity as 3 times/wk or more. The covariates adjusted for in incidence analyses included age, sex, educational status (having/not having tertiary qualifications), and occupational status (employed or unemployed).
Of the 3654 participants at baseline, 2639 had information on all 4 healthy factors. As in EPIC-Potsdam, participants who had diabetes (n = 208 [7.9%]), MI (n = 219 [8.3%]), stroke (n = 84 [10.9%]), and cancer (n = 189 [7.2%]) at baseline were excluded from analyses. Of the remaining participants, 50.0% had a healthy diet score, 82.5% had a body mass index lower than 30 (calculated as weight in kilograms divided by height in meters squared), 48.2% had never smoked, and 44.1% had participated in physical activity at least 3 times/wk. After adjusting for age, sex, and educational and occupational status, the risk of developing incident diabetes (P value for linear trend, < .001) and MI (P value for linear trend, < .001) decreased as the number of healthy lifestyle factors increased (Table), but this was not observed for incident stroke. Having 1 or more healthful factors compared with 0 factors did not lower the risk of incident MI and stroke. However, having all 4 healthy lifestyle factors had the greatest impact on incident diabetes—an 83% risk reduction.
In our older population, a slightly higher proportion (11.4%) of participants than in the EPIC-Potsdam study (9.1%) adhered to all 4 healthful factors.1 The BMES participants with all 4 healthy lifestyle factors had an 83% reduced risk of incident diabetes, and a significant linear trend was observed for incident MI, reinforcing the findings by Ford et al.1 In contrast, having all 4 healthy lifestyle factors among the BMES participants did not significantly reduce the risk of incident stroke. As recommended by Katz et al,3 refinement of dietary quality (eg, including fish consumption, lean vs fattier meats) may have strengthened observed associations between lifestyle and health outcomes in our study. Nevertheless, our findings in a population older than those in the EPIC-Potsdam study1 concur with its take-home message, and that from other prospective studies,4- 6 that healthful dietary and lifestyle factors are beneficial in reducing the risk of developing chronic diseases, particularly diabetes.
Correspondence: Dr Mitchell, Centre for Vision Research, University of Sydney, Westmead Hospital, Hawkesbury Road, Westmead, New South Wales, Australia 2145 (firstname.lastname@example.org).
Author Contributions:Study concept and design: Gopinath and Mitchell. Acquisition of data: Mitchell. Analysis and interpretation of data: Gopinath, Rochtchina, Flood, and Mitchell. Drafting of the manuscript: Gopinath. Critical revision of the manuscript for important intellectual content: Gopinath, Rochtchina, Flood, and Mitchell. Statistical analysis: Rochtchina. Obtained funding: Mitchell. Administrative, technical, and material support: Flood and Mitchell. Study supervision: Gopinath and Mitchell.
Financial Disclosure: None reported.