Lower Vegetable Variety and Worsening Diet Quality Over Time Are Associated With Higher 15-Year Health Care Claims and Costs Among Australian Women

Abstract

BackgroundThe relationship between diet quality and health care costs is unclear. ObjectiveThe aim of this study was to investigate the relationship between baseline diet quality and change in diet quality over time, with 15-year cumulative health care claims/costs. DesignData from a longitudinal cohort study were analyzed. Participants/settingData for survey 3 (2001) (n = 7,868) and survey 7 (2013) (n = 6,349 both time points) from the 1946-1951 cohort of the Australian Longitudinal Study on Women’s Health were analyzed. Main outcome measuresDiet quality was assessed using the Australian Recommended Food Score (ARFS). Fifteen-year cumulative Medicare Benefits Schedule (Australia’s universal health care coverage) data were reported by baseline ARFS quintile and category of diet quality change (“diet quality worsened” [ARFS change ≤ –4 points], “remained stable” [–3 ≤ change in ARFS ≤3 points], or “improved” [ARFS change ≥4 points]). Statistical analysesLinear regression analyses were conducted adjusting for area of residence, socioeconomic status, lifestyle factors, and private health insurance status. ResultsConsuming a greater variety of vegetables at baseline but fewer fruit and dairy products was associated with lower health care costs. For every 1-point increment in the ARFS vegetable subscale, women made 3.3 (95% CI, 1.6-5.0) fewer claims and incurred AU$227 (95% CI, AU$104-350 [US$158; 95% CI, US$72-243]) less in costs. Women whose diet quality worsened over time made more claims (median, 251 claims; quintile 1, quintile 3 [Q1; Q3], 168; 368 claims) and incurred higher costs (AU$15,519; Q1; Q3, AU$9,226; AU$24,847 [US$10,793; Q1; Q3, US$6,417; US$17,281]) compared with those whose diet quality remained stable (median, 236 claims [Q1; Q3, 158; 346 claims], AU$14,515; Q1; Q3, AU$8,539; AU$23,378 [US$10,095; Q1; Q3, US$5,939; US$16,259]). ConclusionsGreater vegetable variety was associated with fewer health care claims and costs; however, this trend was not consistent across other subscales. Worsening diet quality over 12 years was linked with higher health care claims and costs.