Olfactory Impairment and the Risk of Major Adverse Cardiovascular Outcomes in Older Adults

Abstract

Background: Olfactory impairment is common in older adults and may be associated with adverse cardiovascular health; however, empirical evidence is sparse. We examined olfaction in relation to the risk of coronary heart disease (CHD), stroke, and congestive heart failure (CHF).

Methods and results: This study included 2537 older adults (aged 75.6±2.8 years) from the Health ABC (Health, Aging, and Body Composition) study with olfaction assessed by the 12-item Brief Smell Identification Test in 1999 to 2000, defined as poor (score ≤8), moderate (9-10), or good (11-12). The outcomes were incident CHD, stroke, and CHF. During up to a 12-year follow-up, 353 incident CHD, 258 stroke, and 477 CHF events were identified. Olfaction was statistically significantly associated with incident CHF, but not with CHD or stroke. After adjusting for demographics, risk factors, and biomarkers of CHF, the cause-specific hazard ratio (HR) of CHF was 1.32 (95% CI, 1.05-1.66) for moderate and 1.28 (95% CI, 1.01-1.64) for poor olfaction. These associations were robust in preplanned subgroup analyses by age, sex, race, and prevalent CHD/stroke. While the subgroup results were not statistically significantly different, the association of olfaction with CHF appeared to be evident among participants who reported very good to excellent health (HR, 1.47 [95% CI, 1.01-2.14] for moderate; and 1.76 [95% CI, 1.20-2.58] for poor olfaction), but not among those with fair to poor self-reported health (HR, 1.04 [95% CI, 0.64-1.70] for moderate; and 0.92 [95% CI, 0.58-1.47] for poor olfaction).

Conclusions: In community-dwelling older adults, a single olfaction test was associated with a long-term risk for incident CHF, particularly among those reporting very good to excellent health.

Keywords: congestive heart failure; coronary heart disease; older adults; olfaction; self‐reported health status; stroke.

Figure 1. Cumulative incidence function by baseline olfaction status (good, moderate, poor) of (A) CHD and its competing event of death (n=1924); (B) stroke and its competing event of death (n=2330); and (C) CHF and its competing event of death (n=2421). CHD indicates coronary heart diseases; and CHF, congestive heart failure.

Figure 2. Cause‐specific HRs and 95% CIs of olfaction in relation to congestive heart failure with up to 12 years of follow‐up in subgroup analyses (n=2421).

Each model was adjusted for the interaction between baseline olfaction status and the subgroup factor of interest, plus covariates of age, sex, race, education, study site, smoking status, brisk walking, body mass index, self‐reported general health status, systolic blood pressure, use of antihypertensive medications, diabetes, depressive symptoms, total cholesterol, high‐density lipoprotein cholesterol, prevalent coronary heart diseases/stroke, heart rate, left ventricular hypertrophy, abnormal lung function, albumin and estimated glomerular filtration rate, stratified by the tertile of interleukin‐6. GHS indicates general health status; and HR, hazard ratio.

Figure 3. Cause‐specific HRs and 95% CIs for CHF by continuous olfaction score among participants who self‐reported very good to excellent health (n=1100).

Olfaction was measured by the B‐SIT, the perfect score of which as 12 was used to be the reference. The model was adjusted for age, sex, race, education, study site, smoking status, brisk walking, body mass index, use of antihypertensive medications, diabetes, depressive symptoms, total cholesterol, high‐density lipoprotein cholesterol, prevalent coronary heart disease/stroke, heart rate, left ventricular hypertrophy, abnormal lung function, albumin, interleukin‐6, and estimated glomerular filtration rate, stratified by groups of systolic blood pressure (140 mm Hg as the cutoff). B‐SIT indicates Brief Smell Identification test; CHF, congestive heart failure; and HR, hazard ratio.